Merge from rust-lang/rust

896 files changed, 8004 insertions, 3948 deletions

diff --git a/src/bootstrap/Cargo.lock b/src/bootstrap/Cargo.lock
index 0c8e6633560..a6ca699e282 100644
--- a/src/bootstrap/Cargo.lock
+++ b/src/bootstrap/Cargo.lock
@@ -44,6 +44,7 @@ dependencies = [
  "fd-lock",
  "home",
  "ignore",
+ "insta",
  "junction",
  "libc",
  "object",
@@ -159,6 +160,18 @@ dependencies = [
 ]
 
 [[package]]
+name = "console"
+version = "0.15.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "054ccb5b10f9f2cbf51eb355ca1d05c2d279ce1804688d0db74b4733a5aeafd8"
+dependencies = [
+ "encode_unicode",
+ "libc",
+ "once_cell",
+ "windows-sys 0.59.0",
+]
+
+[[package]]
 name = "cpufeatures"
 version = "0.2.15"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -219,6 +232,12 @@ dependencies = [
 ]
 
 [[package]]
+name = "encode_unicode"
+version = "1.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "34aa73646ffb006b8f5147f3dc182bd4bcb190227ce861fc4a4844bf8e3cb2c0"
+
+[[package]]
 name = "errno"
 version = "0.3.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -324,6 +343,17 @@ dependencies = [
 ]
 
 [[package]]
+name = "insta"
+version = "1.43.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "154934ea70c58054b556dd430b99a98c2a7ff5309ac9891597e339b5c28f4371"
+dependencies = [
+ "console",
+ "once_cell",
+ "similar",
+]
+
+[[package]]
 name = "itoa"
 version = "1.0.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -676,6 +706,12 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0fda2ff0d084019ba4d7c6f371c95d8fd75ce3524c3cb8fb653a3023f6323e64"
 
 [[package]]
+name = "similar"
+version = "2.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bbbb5d9659141646ae647b42fe094daf6c6192d1620870b449d9557f748b2daa"
+
+[[package]]
 name = "smallvec"
 version = "1.13.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
diff --git a/src/bootstrap/Cargo.toml b/src/bootstrap/Cargo.toml
index b12b3dfc7b2..9785a306c9b 100644
--- a/src/bootstrap/Cargo.toml
+++ b/src/bootstrap/Cargo.toml
@@ -84,6 +84,7 @@ features = [
 [dev-dependencies]
 pretty_assertions = "1.4"
 tempfile = "3.15.0"
+insta = "1.43"
 
 # We care a lot about bootstrap's compile times, so don't include debuginfo for
 # dependencies, only bootstrap itself.
diff --git a/src/bootstrap/README.md b/src/bootstrap/README.md
index f9d7c811f60..5ff999f01a9 100644
--- a/src/bootstrap/README.md
+++ b/src/bootstrap/README.md
@@ -200,6 +200,10 @@ please file issues on the [Rust issue tracker][rust-issue-tracker].
 [rust-bootstrap-zulip]: https://rust-lang.zulipchat.com/#narrow/stream/t-infra.2Fbootstrap
 [rust-issue-tracker]: https://github.com/rust-lang/rust/issues
 
+## Testing
+
+To run bootstrap tests, execute `x test bootstrap`. If you want to bless snapshot tests, then install `cargo-insta` (`cargo install cargo-insta`) and then run `cargo insta review --manifest-path src/bootstrap/Cargo.toml`.
+
 ## Changelog
 
 Because we do not release bootstrap with versions, we also do not maintain CHANGELOG files. To
diff --git a/src/bootstrap/src/core/build_steps/check.rs b/src/bootstrap/src/core/build_steps/check.rs
index 911a51b0e16..f47873590a1 100644
--- a/src/bootstrap/src/core/build_steps/check.rs
+++ b/src/bootstrap/src/core/build_steps/check.rs
@@ -89,7 +89,7 @@ impl Step for Std {
         let stage = self.custom_stage.unwrap_or(builder.top_stage);
 
         let target = self.target;
-        let compiler = builder.compiler(stage, builder.config.build);
+        let compiler = builder.compiler(stage, builder.config.host_target);
 
         if stage == 0 {
             let mut is_explicitly_called =
@@ -244,7 +244,7 @@ impl Step for Rustc {
     /// the `compiler` targeting the `target` architecture. The artifacts
     /// created will also be linked into the sysroot directory.
     fn run(self, builder: &Builder<'_>) {
-        let compiler = builder.compiler(builder.top_stage, builder.config.build);
+        let compiler = builder.compiler(builder.top_stage, builder.config.host_target);
         let target = self.target;
 
         if compiler.stage != 0 {
@@ -327,7 +327,7 @@ impl Step for CodegenBackend {
             return;
         }
 
-        let compiler = builder.compiler(builder.top_stage, builder.config.build);
+        let compiler = builder.compiler(builder.top_stage, builder.config.host_target);
         let target = self.target;
         let backend = self.backend;
 
@@ -382,7 +382,7 @@ impl Step for RustAnalyzer {
     }
 
     fn run(self, builder: &Builder<'_>) {
-        let compiler = builder.compiler(builder.top_stage, builder.config.build);
+        let compiler = builder.compiler(builder.top_stage, builder.config.host_target);
         let target = self.target;
 
         builder.ensure(Rustc::new(target, builder));
@@ -448,7 +448,7 @@ impl Step for Compiletest {
 
         let compiler = builder.compiler(
             if mode == Mode::ToolBootstrap { 0 } else { builder.top_stage },
-            builder.config.build,
+            builder.config.host_target,
         );
 
         if mode != Mode::ToolBootstrap {
@@ -527,7 +527,7 @@ fn run_tool_check_step(
     path: &str,
 ) {
     let display_name = path.rsplit('/').next().unwrap();
-    let compiler = builder.compiler(builder.top_stage, builder.config.build);
+    let compiler = builder.compiler(builder.top_stage, builder.config.host_target);
 
     builder.ensure(Rustc::new(target, builder));
 
@@ -614,7 +614,7 @@ impl Step for CoverageDump {
         // Make sure we haven't forgotten any fields, if there are any.
         let Self {} = self;
         let display_name = "coverage-dump";
-        let host = builder.config.build;
+        let host = builder.config.host_target;
         let target = host;
         let mode = Mode::ToolBootstrap;
 
diff --git a/src/bootstrap/src/core/build_steps/clippy.rs b/src/bootstrap/src/core/build_steps/clippy.rs
index 0652c08ff49..788a3b9601d 100644
--- a/src/bootstrap/src/core/build_steps/clippy.rs
+++ b/src/bootstrap/src/core/build_steps/clippy.rs
@@ -144,7 +144,7 @@ impl Step for Std {
         builder.require_submodule("library/stdarch", None);
 
         let target = self.target;
-        let compiler = builder.compiler(builder.top_stage, builder.config.build);
+        let compiler = builder.compiler(builder.top_stage, builder.config.host_target);
 
         let mut cargo = builder::Cargo::new(
             builder,
@@ -204,7 +204,7 @@ impl Step for Rustc {
     /// This will lint the compiler for a particular stage of the build using
     /// the `compiler` targeting the `target` architecture.
     fn run(self, builder: &Builder<'_>) {
-        let compiler = builder.compiler(builder.top_stage, builder.config.build);
+        let compiler = builder.compiler(builder.top_stage, builder.config.host_target);
         let target = self.target;
 
         if !builder.download_rustc() {
@@ -285,7 +285,7 @@ macro_rules! lint_any {
             }
 
             fn run(self, builder: &Builder<'_>) -> Self::Output {
-                let compiler = builder.compiler(builder.top_stage, builder.config.build);
+                let compiler = builder.compiler(builder.top_stage, builder.config.host_target);
                 let target = self.target;
 
                 if !builder.download_rustc() {
diff --git a/src/bootstrap/src/core/build_steps/compile.rs b/src/bootstrap/src/core/build_steps/compile.rs
index 5ecce31fe15..52f421b4782 100644
--- a/src/bootstrap/src/core/build_steps/compile.rs
+++ b/src/bootstrap/src/core/build_steps/compile.rs
@@ -35,6 +35,7 @@ use crate::utils::helpers::{
 };
 use crate::{CLang, Compiler, DependencyType, FileType, GitRepo, LLVM_TOOLS, Mode, debug, trace};
 
+/// Build a standard library for the given `target` using the given `compiler`.
 #[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
 pub struct Std {
     pub target: TargetSelection,
@@ -159,7 +160,7 @@ impl Step for Std {
         let compiler = if builder.download_rustc() && self.force_recompile {
             // When there are changes in the library tree with CI-rustc, we want to build
             // the stageN library and that requires using stageN-1 compiler.
-            builder.compiler(self.compiler.stage.saturating_sub(1), builder.config.build)
+            builder.compiler(self.compiler.stage.saturating_sub(1), builder.config.host_target)
         } else {
             self.compiler
         };
@@ -301,7 +302,7 @@ impl Step for Std {
 
         builder.ensure(StdLink::from_std(
             self,
-            builder.compiler(compiler.stage, builder.config.build),
+            builder.compiler(compiler.stage, builder.config.host_target),
         ));
     }
 }
@@ -960,11 +961,18 @@ fn cp_rustc_component_to_ci_sysroot(builder: &Builder<'_>, sysroot: &Path, conte
     }
 }
 
+/// Build rustc using the passed `build_compiler`.
+///
+/// - Makes sure that `build_compiler` has a standard library prepared for its host target,
+///   so that it can compile build scripts and proc macros when building this `rustc`.
+/// - Makes sure that `build_compiler` has a standard library prepared for `target`,
+///   so that the built `rustc` can *link to it* and use it at runtime.
 #[derive(Debug, PartialOrd, Ord, Clone, PartialEq, Eq, Hash)]
 pub struct Rustc {
+    /// The target on which rustc will run (its host).
     pub target: TargetSelection,
-    /// The **previous** compiler used to compile this compiler.
-    pub compiler: Compiler,
+    /// The **previous** compiler used to compile this rustc.
+    pub build_compiler: Compiler,
     /// Whether to build a subset of crates, rather than the whole compiler.
     ///
     /// This should only be requested by the user, not used within bootstrap itself.
@@ -974,8 +982,8 @@ pub struct Rustc {
 }
 
 impl Rustc {
-    pub fn new(compiler: Compiler, target: TargetSelection) -> Self {
-        Self { target, compiler, crates: Default::default() }
+    pub fn new(build_compiler: Compiler, target: TargetSelection) -> Self {
+        Self { target, build_compiler, crates: Default::default() }
     }
 }
 
@@ -1007,7 +1015,7 @@ impl Step for Rustc {
     fn make_run(run: RunConfig<'_>) {
         let crates = run.cargo_crates_in_set();
         run.builder.ensure(Rustc {
-            compiler: run
+            build_compiler: run
                 .builder
                 .compiler(run.builder.top_stage.saturating_sub(1), run.build_triple()),
             target: run.target,
@@ -1018,7 +1026,7 @@ impl Step for Rustc {
     /// Builds the compiler.
     ///
     /// This will build the compiler for a particular stage of the build using
-    /// the `compiler` targeting the `target` architecture. The artifacts
+    /// the `build_compiler` targeting the `target` architecture. The artifacts
     /// created will also be linked into the sysroot directory.
     #[cfg_attr(
         feature = "tracing",
@@ -1026,54 +1034,58 @@ impl Step for Rustc {
             level = "debug",
             name = "Rustc::run",
             skip_all,
-            fields(previous_compiler = ?self.compiler, target = ?self.target),
+            fields(previous_compiler = ?self.build_compiler, target = ?self.target),
         ),
     )]
     fn run(self, builder: &Builder<'_>) -> u32 {
-        let compiler = self.compiler;
+        let build_compiler = self.build_compiler;
         let target = self.target;
 
         // NOTE: the ABI of the stage0 compiler is different from the ABI of the downloaded compiler,
         // so its artifacts can't be reused.
-        if builder.download_rustc() && compiler.stage != 0 {
-            trace!(stage = compiler.stage, "`download_rustc` requested");
+        if builder.download_rustc() && build_compiler.stage != 0 {
+            trace!(stage = build_compiler.stage, "`download_rustc` requested");
 
-            let sysroot = builder.ensure(Sysroot { compiler, force_recompile: false });
+            let sysroot =
+                builder.ensure(Sysroot { compiler: build_compiler, force_recompile: false });
             cp_rustc_component_to_ci_sysroot(
                 builder,
                 &sysroot,
                 builder.config.ci_rustc_dev_contents(),
             );
-            return compiler.stage;
+            return build_compiler.stage;
         }
 
-        builder.ensure(Std::new(compiler, target));
+        // Build a standard library for `target` using the `build_compiler`.
+        // This will be the standard library that the rustc which we build *links to*.
+        builder.ensure(Std::new(build_compiler, target));
 
-        if builder.config.keep_stage.contains(&compiler.stage) {
-            trace!(stage = compiler.stage, "`keep-stage` requested");
+        if builder.config.keep_stage.contains(&build_compiler.stage) {
+            trace!(stage = build_compiler.stage, "`keep-stage` requested");
 
             builder.info("WARNING: Using a potentially old librustc. This may not behave well.");
             builder.info("WARNING: Use `--keep-stage-std` if you want to rebuild the compiler when it changes");
-            builder.ensure(RustcLink::from_rustc(self, compiler));
+            builder.ensure(RustcLink::from_rustc(self, build_compiler));
 
-            return compiler.stage;
+            return build_compiler.stage;
         }
 
-        let compiler_to_use = builder.compiler_for(compiler.stage, compiler.host, target);
-        if compiler_to_use != compiler {
+        let compiler_to_use =
+            builder.compiler_for(build_compiler.stage, build_compiler.host, target);
+        if compiler_to_use != build_compiler {
             builder.ensure(Rustc::new(compiler_to_use, target));
             let msg = if compiler_to_use.host == target {
                 format!(
                     "Uplifting rustc (stage{} -> stage{})",
                     compiler_to_use.stage,
-                    compiler.stage + 1
+                    build_compiler.stage + 1
                 )
             } else {
                 format!(
                     "Uplifting rustc (stage{}:{} -> stage{}:{})",
                     compiler_to_use.stage,
                     compiler_to_use.host,
-                    compiler.stage + 1,
+                    build_compiler.stage + 1,
                     target
                 )
             };
@@ -1082,22 +1094,26 @@ impl Step for Rustc {
             return compiler_to_use.stage;
         }
 
-        // Ensure that build scripts and proc macros have a std / libproc_macro to link against.
+        // Build a standard library for the current host target using the `build_compiler`.
+        // This standard library will be used when building `rustc` for compiling
+        // build scripts and proc macros.
+        // If we are not cross-compiling, the Std build above will be the same one as the one we
+        // prepare here.
         builder.ensure(Std::new(
-            builder.compiler(self.compiler.stage, builder.config.build),
-            builder.config.build,
+            builder.compiler(self.build_compiler.stage, builder.config.host_target),
+            builder.config.host_target,
         ));
 
         let mut cargo = builder::Cargo::new(
             builder,
-            compiler,
+            build_compiler,
             Mode::Rustc,
             SourceType::InTree,
             target,
             Kind::Build,
         );
 
-        rustc_cargo(builder, &mut cargo, target, &compiler, &self.crates);
+        rustc_cargo(builder, &mut cargo, target, &build_compiler, &self.crates);
 
         // NB: all RUSTFLAGS should be added to `rustc_cargo()` so they will be
         // consistently applied by check/doc/test modes too.
@@ -1106,19 +1122,19 @@ impl Step for Rustc {
             cargo.arg("-p").arg(krate);
         }
 
-        if builder.build.config.enable_bolt_settings && compiler.stage == 1 {
+        if builder.build.config.enable_bolt_settings && build_compiler.stage == 1 {
             // Relocations are required for BOLT to work.
             cargo.env("RUSTC_BOLT_LINK_FLAGS", "1");
         }
 
         let _guard = builder.msg_sysroot_tool(
             Kind::Build,
-            compiler.stage,
+            build_compiler.stage,
             format_args!("compiler artifacts{}", crate_description(&self.crates)),
-            compiler.host,
+            build_compiler.host,
             target,
         );
-        let stamp = build_stamp::librustc_stamp(builder, compiler, target);
+        let stamp = build_stamp::librustc_stamp(builder, build_compiler, target);
         run_cargo(
             builder,
             cargo,
@@ -1150,10 +1166,10 @@ impl Step for Rustc {
 
         builder.ensure(RustcLink::from_rustc(
             self,
-            builder.compiler(compiler.stage, builder.config.build),
+            builder.compiler(build_compiler.stage, builder.config.host_target),
         ));
 
-        compiler.stage
+        build_compiler.stage
     }
 }
 
@@ -1161,7 +1177,7 @@ pub fn rustc_cargo(
     builder: &Builder<'_>,
     cargo: &mut Cargo,
     target: TargetSelection,
-    compiler: &Compiler,
+    build_compiler: &Compiler,
     crates: &[String],
 ) {
     cargo
@@ -1190,11 +1206,11 @@ pub fn rustc_cargo(
     // We want to link against registerEnzyme and in the future we want to use additional
     // functionality from Enzyme core. For that we need to link against Enzyme.
     if builder.config.llvm_enzyme {
-        let arch = builder.build.build;
+        let arch = builder.build.host_target;
         let enzyme_dir = builder.build.out.join(arch).join("enzyme").join("lib");
         cargo.rustflag("-L").rustflag(enzyme_dir.to_str().expect("Invalid path"));
 
-        if let Some(llvm_config) = builder.llvm_config(builder.config.build) {
+        if let Some(llvm_config) = builder.llvm_config(builder.config.host_target) {
             let llvm_version_major = llvm::get_llvm_version_major(builder, &llvm_config);
             cargo.rustflag("-l").rustflag(&format!("Enzyme-{llvm_version_major}"));
         }
@@ -1208,7 +1224,7 @@ pub fn rustc_cargo(
         cargo.rustflag("-Zdefault-visibility=protected");
     }
 
-    if is_lto_stage(compiler) {
+    if is_lto_stage(build_compiler) {
         match builder.config.rust_lto {
             RustcLto::Thin | RustcLto::Fat => {
                 // Since using LTO for optimizing dylibs is currently experimental,
@@ -1241,7 +1257,7 @@ pub fn rustc_cargo(
     // is already on by default in MSVC optimized builds, which is interpreted as --icf=all:
     // https://github.com/llvm/llvm-project/blob/3329cec2f79185bafd678f310fafadba2a8c76d2/lld/COFF/Driver.cpp#L1746
     // https://github.com/rust-lang/rust/blob/f22819bcce4abaff7d1246a56eec493418f9f4ee/compiler/rustc_codegen_ssa/src/back/linker.rs#L827
-    if builder.config.lld_mode.is_used() && !compiler.host.is_msvc() {
+    if builder.config.lld_mode.is_used() && !build_compiler.host.is_msvc() {
         cargo.rustflag("-Clink-args=-Wl,--icf=all");
     }
 
@@ -1249,7 +1265,7 @@ pub fn rustc_cargo(
         panic!("Cannot use and generate PGO profiles at the same time");
     }
     let is_collecting = if let Some(path) = &builder.config.rust_profile_generate {
-        if compiler.stage == 1 {
+        if build_compiler.stage == 1 {
             cargo.rustflag(&format!("-Cprofile-generate={path}"));
             // Apparently necessary to avoid overflowing the counters during
             // a Cargo build profile
@@ -1259,7 +1275,7 @@ pub fn rustc_cargo(
             false
         }
     } else if let Some(path) = &builder.config.rust_profile_use {
-        if compiler.stage == 1 {
+        if build_compiler.stage == 1 {
             cargo.rustflag(&format!("-Cprofile-use={path}"));
             if builder.is_verbose() {
                 cargo.rustflag("-Cllvm-args=-pgo-warn-missing-function");
@@ -1284,20 +1300,20 @@ pub fn rustc_cargo(
     // useful.
     // This is only performed for non-incremental builds, as ccache cannot deal with these.
     if let Some(ref ccache) = builder.config.ccache
-        && compiler.stage == 0
+        && build_compiler.stage == 0
         && !builder.config.incremental
     {
         cargo.env("RUSTC_WRAPPER", ccache);
     }
 
-    rustc_cargo_env(builder, cargo, target, compiler.stage);
+    rustc_cargo_env(builder, cargo, target, build_compiler.stage);
 }
 
 pub fn rustc_cargo_env(
     builder: &Builder<'_>,
     cargo: &mut Cargo,
     target: TargetSelection,
-    stage: u32,
+    build_stage: u32,
 ) {
     // Set some configuration variables picked up by build scripts and
     // the compiler alike
@@ -1364,7 +1380,7 @@ pub fn rustc_cargo_env(
             crate::core::build_steps::llvm::prebuilt_llvm_config(builder, target, false)
                 .should_build();
         // `top_stage == stage` might be false for `check --stage 1`, if we are building the stage 1 compiler
-        let can_skip_build = builder.kind == Kind::Check && builder.top_stage == stage;
+        let can_skip_build = builder.kind == Kind::Check && builder.top_stage == build_stage;
         let should_skip_build = building_is_expensive && can_skip_build;
         if !should_skip_build {
             rustc_llvm_env(builder, cargo, target)
@@ -1475,7 +1491,7 @@ impl RustcLink {
     fn from_rustc(rustc: Rustc, host_compiler: Compiler) -> Self {
         Self {
             compiler: host_compiler,
-            previous_stage_compiler: rustc.compiler,
+            previous_stage_compiler: rustc.build_compiler,
             target: rustc.target,
             crates: rustc.crates,
         }
@@ -1813,7 +1829,7 @@ impl Step for Sysroot {
         // If we're downloading a compiler from CI, we can use the same compiler for all stages other than 0.
         if builder.download_rustc() && compiler.stage != 0 {
             assert_eq!(
-                builder.config.build, compiler.host,
+                builder.config.host_target, compiler.host,
                 "Cross-compiling is not yet supported with `download-rustc`",
             );
 
@@ -1967,7 +1983,7 @@ impl Step for Assemble {
         if target_compiler.stage == 0 {
             trace!("stage 0 build compiler is always available, simply returning");
             assert_eq!(
-                builder.config.build, target_compiler.host,
+                builder.config.host_target, target_compiler.host,
                 "Cannot obtain compiler for non-native build triple at stage 0"
             );
             // The stage 0 compiler for the build triple is always pre-built.
@@ -2080,27 +2096,29 @@ impl Step for Assemble {
         debug!(
             "ensuring build compiler is available: compiler(stage = {}, host = {:?})",
             target_compiler.stage - 1,
-            builder.config.build,
+            builder.config.host_target,
         );
-        let mut build_compiler = builder.compiler(target_compiler.stage - 1, builder.config.build);
+        let mut build_compiler =
+            builder.compiler(target_compiler.stage - 1, builder.config.host_target);
 
         // Build enzyme
         if builder.config.llvm_enzyme && !builder.config.dry_run() {
             debug!("`llvm_enzyme` requested");
             let enzyme_install = builder.ensure(llvm::Enzyme { target: build_compiler.host });
-            let llvm_config = builder.llvm_config(builder.config.build).unwrap();
-            let llvm_version_major = llvm::get_llvm_version_major(builder, &llvm_config);
-            let lib_ext = std::env::consts::DLL_EXTENSION;
-            let libenzyme = format!("libEnzyme-{llvm_version_major}");
-            let src_lib =
-                enzyme_install.join("build/Enzyme").join(&libenzyme).with_extension(lib_ext);
-            let libdir = builder.sysroot_target_libdir(build_compiler, build_compiler.host);
-            let target_libdir =
-                builder.sysroot_target_libdir(target_compiler, target_compiler.host);
-            let dst_lib = libdir.join(&libenzyme).with_extension(lib_ext);
-            let target_dst_lib = target_libdir.join(&libenzyme).with_extension(lib_ext);
-            builder.copy_link(&src_lib, &dst_lib, FileType::NativeLibrary);
-            builder.copy_link(&src_lib, &target_dst_lib, FileType::NativeLibrary);
+            if let Some(llvm_config) = builder.llvm_config(builder.config.host_target) {
+                let llvm_version_major = llvm::get_llvm_version_major(builder, &llvm_config);
+                let lib_ext = std::env::consts::DLL_EXTENSION;
+                let libenzyme = format!("libEnzyme-{llvm_version_major}");
+                let src_lib =
+                    enzyme_install.join("build/Enzyme").join(&libenzyme).with_extension(lib_ext);
+                let libdir = builder.sysroot_target_libdir(build_compiler, build_compiler.host);
+                let target_libdir =
+                    builder.sysroot_target_libdir(target_compiler, target_compiler.host);
+                let dst_lib = libdir.join(&libenzyme).with_extension(lib_ext);
+                let target_dst_lib = target_libdir.join(&libenzyme).with_extension(lib_ext);
+                builder.copy_link(&src_lib, &dst_lib, FileType::NativeLibrary);
+                builder.copy_link(&src_lib, &target_dst_lib, FileType::NativeLibrary);
+            }
         }
 
         // Build the libraries for this compiler to link to (i.e., the libraries
diff --git a/src/bootstrap/src/core/build_steps/dist.rs b/src/bootstrap/src/core/build_steps/dist.rs
index 587fca80374..e0f632eda0e 100644
--- a/src/bootstrap/src/core/build_steps/dist.rs
+++ b/src/bootstrap/src/core/build_steps/dist.rs
@@ -422,7 +422,7 @@ impl Step for Rustc {
             }
 
             let ra_proc_macro_srv_compiler =
-                builder.compiler_for(compiler.stage, builder.config.build, compiler.host);
+                builder.compiler_for(compiler.stage, builder.config.host_target, compiler.host);
             builder.ensure(compile::Rustc::new(ra_proc_macro_srv_compiler, compiler.host));
 
             if let Some(ra_proc_macro_srv) = builder.ensure_if_default(
@@ -696,7 +696,7 @@ impl Step for Std {
         run.builder.ensure(Std {
             compiler: run.builder.compiler_for(
                 run.builder.top_stage,
-                run.builder.config.build,
+                run.builder.config.host_target,
                 run.target,
             ),
             target: run.target,
@@ -748,7 +748,7 @@ impl Step for RustcDev {
         run.builder.ensure(RustcDev {
             compiler: run.builder.compiler_for(
                 run.builder.top_stage,
-                run.builder.config.build,
+                run.builder.config.host_target,
                 run.target,
             ),
             target: run.target,
@@ -815,7 +815,7 @@ impl Step for Analysis {
             // through the sysroot uplifting.
             compiler: run.builder.compiler_for(
                 run.builder.top_stage,
-                run.builder.config.build,
+                run.builder.config.host_target,
                 run.target,
             ),
             target: run.target,
@@ -1168,7 +1168,7 @@ impl Step for Cargo {
         run.builder.ensure(Cargo {
             compiler: run.builder.compiler_for(
                 run.builder.top_stage,
-                run.builder.config.build,
+                run.builder.config.host_target,
                 run.target,
             ),
             target: run.target,
@@ -1224,7 +1224,7 @@ impl Step for RustAnalyzer {
         run.builder.ensure(RustAnalyzer {
             compiler: run.builder.compiler_for(
                 run.builder.top_stage,
-                run.builder.config.build,
+                run.builder.config.host_target,
                 run.target,
             ),
             target: run.target,
@@ -1268,7 +1268,7 @@ impl Step for Clippy {
         run.builder.ensure(Clippy {
             compiler: run.builder.compiler_for(
                 run.builder.top_stage,
-                run.builder.config.build,
+                run.builder.config.host_target,
                 run.target,
             ),
             target: run.target,
@@ -1317,7 +1317,7 @@ impl Step for Miri {
         run.builder.ensure(Miri {
             compiler: run.builder.compiler_for(
                 run.builder.top_stage,
-                run.builder.config.build,
+                run.builder.config.host_target,
                 run.target,
             ),
             target: run.target,
@@ -1462,7 +1462,7 @@ impl Step for Rustfmt {
         run.builder.ensure(Rustfmt {
             compiler: run.builder.compiler_for(
                 run.builder.top_stage,
-                run.builder.config.build,
+                run.builder.config.host_target,
                 run.target,
             ),
             target: run.target,
@@ -1507,7 +1507,7 @@ impl Step for Extended {
     fn make_run(run: RunConfig<'_>) {
         run.builder.ensure(Extended {
             stage: run.builder.top_stage,
-            host: run.builder.config.build,
+            host: run.builder.config.host_target,
             target: run.target,
         });
     }
@@ -1681,7 +1681,8 @@ impl Step for Extended {
             cmd.run(builder);
         }
 
-        if target.is_windows() {
+        // FIXME(mati865): `gnullvm` here is temporary, remove it once it can host itself
+        if target.is_windows() && !target.contains("gnullvm") {
             let exe = tmp.join("exe");
             let _ = fs::remove_dir_all(&exe);
 
@@ -2156,7 +2157,7 @@ fn maybe_install_llvm(
         cmd.arg("--libfiles");
         builder.verbose(|| println!("running {cmd:?}"));
         let files = cmd.run_capture_stdout(builder).stdout();
-        let build_llvm_out = &builder.llvm_out(builder.config.build);
+        let build_llvm_out = &builder.llvm_out(builder.config.host_target);
         let target_llvm_out = &builder.llvm_out(target);
         for file in files.trim_end().split(' ') {
             // If we're not using a custom LLVM, make sure we package for the target.
@@ -2340,7 +2341,7 @@ impl Step for LlvmBitcodeLinker {
         run.builder.ensure(LlvmBitcodeLinker {
             compiler: run.builder.compiler_for(
                 run.builder.top_stage,
-                run.builder.config.build,
+                run.builder.config.host_target,
                 run.target,
             ),
             target: run.target,
diff --git a/src/bootstrap/src/core/build_steps/doc.rs b/src/bootstrap/src/core/build_steps/doc.rs
index 7fccf85a0ea..215c155651a 100644
--- a/src/bootstrap/src/core/build_steps/doc.rs
+++ b/src/bootstrap/src/core/build_steps/doc.rs
@@ -209,7 +209,7 @@ impl Step for TheBook {
 
     fn make_run(run: RunConfig<'_>) {
         run.builder.ensure(TheBook {
-            compiler: run.builder.compiler(run.builder.top_stage, run.builder.config.build),
+            compiler: run.builder.compiler(run.builder.top_stage, run.builder.config.host_target),
             target: run.target,
         });
     }
@@ -329,7 +329,7 @@ impl Step for Standalone {
 
     fn make_run(run: RunConfig<'_>) {
         run.builder.ensure(Standalone {
-            compiler: run.builder.compiler(run.builder.top_stage, run.builder.config.build),
+            compiler: run.builder.compiler(run.builder.top_stage, run.builder.config.host_target),
             target: run.target,
         });
     }
@@ -431,7 +431,7 @@ impl Step for Releases {
 
     fn make_run(run: RunConfig<'_>) {
         run.builder.ensure(Releases {
-            compiler: run.builder.compiler(run.builder.top_stage, run.builder.config.build),
+            compiler: run.builder.compiler(run.builder.top_stage, run.builder.config.host_target),
             target: run.target,
         });
     }
@@ -449,7 +449,7 @@ impl Step for Releases {
         t!(fs::create_dir_all(&out));
 
         builder.ensure(Standalone {
-            compiler: builder.compiler(builder.top_stage, builder.config.build),
+            compiler: builder.compiler(builder.top_stage, builder.config.host_target),
             target,
         });
 
@@ -700,7 +700,7 @@ fn doc_std(
     extra_args: &[&str],
     requested_crates: &[String],
 ) {
-    let compiler = builder.compiler(stage, builder.config.build);
+    let compiler = builder.compiler(stage, builder.config.host_target);
 
     let target_doc_dir_name = if format == DocumentationFormat::Json { "json-doc" } else { "doc" };
     let target_dir = builder.stage_out(compiler, Mode::Std).join(target).join(target_doc_dir_name);
@@ -803,8 +803,8 @@ impl Step for Rustc {
 
         // Build the standard library, so that proc-macros can use it.
         // (Normally, only the metadata would be necessary, but proc-macros are special since they run at compile-time.)
-        let compiler = builder.compiler(stage, builder.config.build);
-        builder.ensure(compile::Std::new(compiler, builder.config.build));
+        let compiler = builder.compiler(stage, builder.config.host_target);
+        builder.ensure(compile::Std::new(compiler, builder.config.host_target));
 
         let _guard = builder.msg_sysroot_tool(
             Kind::Doc,
@@ -946,7 +946,7 @@ macro_rules! tool_doc {
                 let out = builder.compiler_doc_out(target);
                 t!(fs::create_dir_all(&out));
 
-                let compiler = builder.compiler(stage, builder.config.build);
+                let compiler = builder.compiler(stage, builder.config.host_target);
                 builder.ensure(compile::Std::new(compiler, target));
 
                 if true $(&& $rustc_tool)? {
@@ -1174,7 +1174,7 @@ impl Step for RustcBook {
 
     fn make_run(run: RunConfig<'_>) {
         run.builder.ensure(RustcBook {
-            compiler: run.builder.compiler(run.builder.top_stage, run.builder.config.build),
+            compiler: run.builder.compiler(run.builder.top_stage, run.builder.config.host_target),
             target: run.target,
             validate: false,
         });
@@ -1261,7 +1261,7 @@ impl Step for Reference {
 
     fn make_run(run: RunConfig<'_>) {
         run.builder.ensure(Reference {
-            compiler: run.builder.compiler(run.builder.top_stage, run.builder.config.build),
+            compiler: run.builder.compiler(run.builder.top_stage, run.builder.config.host_target),
             target: run.target,
         });
     }
@@ -1272,7 +1272,7 @@ impl Step for Reference {
 
         // This is needed for generating links to the standard library using
         // the mdbook-spec plugin.
-        builder.ensure(compile::Std::new(self.compiler, builder.config.build));
+        builder.ensure(compile::Std::new(self.compiler, builder.config.host_target));
 
         // Run rustbook/mdbook to generate the HTML pages.
         builder.ensure(RustbookSrc {
diff --git a/src/bootstrap/src/core/build_steps/gcc.rs b/src/bootstrap/src/core/build_steps/gcc.rs
index ee8bd8286da..899e3fd9a45 100644
--- a/src/bootstrap/src/core/build_steps/gcc.rs
+++ b/src/bootstrap/src/core/build_steps/gcc.rs
@@ -285,7 +285,7 @@ pub fn add_cg_gcc_cargo_flags(cargo: &mut Cargo, gcc: &GccOutput) {
 /// The absolute path to the downloaded GCC artifacts.
 #[cfg(not(test))]
 fn ci_gcc_root(config: &crate::Config) -> PathBuf {
-    config.out.join(config.build).join("ci-gcc")
+    config.out.join(config.host_target).join("ci-gcc")
 }
 
 /// Detect whether GCC sources have been modified locally or not.
diff --git a/src/bootstrap/src/core/build_steps/install.rs b/src/bootstrap/src/core/build_steps/install.rs
index 5419540aa2e..4434d6658eb 100644
--- a/src/bootstrap/src/core/build_steps/install.rs
+++ b/src/bootstrap/src/core/build_steps/install.rs
@@ -73,7 +73,7 @@ fn install_sh(
     let prefix = default_path(&builder.config.prefix, "/usr/local");
     let sysconfdir = prefix.join(default_path(&builder.config.sysconfdir, "/etc"));
     let destdir_env = env::var_os("DESTDIR").map(PathBuf::from);
-    let is_cygwin = builder.config.build.is_cygwin();
+    let is_cygwin = builder.config.host_target.is_cygwin();
 
     // Sanity checks on the write access of user.
     //
@@ -187,7 +187,7 @@ macro_rules! install {
 
             fn make_run(run: RunConfig<'_>) {
                 run.builder.ensure($name {
-                    compiler: run.builder.compiler(run.builder.top_stage, run.builder.config.build),
+                    compiler: run.builder.compiler(run.builder.top_stage, run.builder.config.host_target),
                     target: run.target,
                 });
             }
@@ -246,7 +246,7 @@ install!((self, builder, _config),
             );
         }
     };
-    LlvmTools, alias = "llvm-tools", _config.llvm_tools_enabled && _config.llvm_enabled(_config.build), only_hosts: true, {
+    LlvmTools, alias = "llvm-tools", _config.llvm_tools_enabled && _config.llvm_enabled(_config.host_target), only_hosts: true, {
         if let Some(tarball) = builder.ensure(dist::LlvmTools { target: self.target }) {
             install_sh(builder, "llvm-tools", self.compiler.stage, Some(self.target), &tarball);
         } else {
diff --git a/src/bootstrap/src/core/build_steps/llvm.rs b/src/bootstrap/src/core/build_steps/llvm.rs
index 2b7703000cb..8f2f143c352 100644
--- a/src/bootstrap/src/core/build_steps/llvm.rs
+++ b/src/bootstrap/src/core/build_steps/llvm.rs
@@ -132,14 +132,14 @@ pub fn prebuilt_llvm_config(
     let build_llvm_config = if let Some(build_llvm_config) = builder
         .config
         .target_config
-        .get(&builder.config.build)
+        .get(&builder.config.host_target)
         .and_then(|config| config.llvm_config.clone())
     {
         build_llvm_config
     } else {
-        let mut llvm_config_ret_dir = builder.llvm_out(builder.config.build);
+        let mut llvm_config_ret_dir = builder.llvm_out(builder.config.host_target);
         llvm_config_ret_dir.push("bin");
-        llvm_config_ret_dir.join(exe("llvm-config", builder.config.build))
+        llvm_config_ret_dir.join(exe("llvm-config", builder.config.host_target))
     };
 
     let llvm_cmake_dir = out_dir.join("lib/cmake/llvm");
@@ -235,8 +235,8 @@ pub(crate) fn is_ci_llvm_available_for_target(config: &Config, asserts: bool) ->
         ("x86_64-unknown-netbsd", false),
     ];
 
-    if !supported_platforms.contains(&(&*config.build.triple, asserts))
-        && (asserts || !supported_platforms.contains(&(&*config.build.triple, true)))
+    if !supported_platforms.contains(&(&*config.host_target.triple, asserts))
+        && (asserts || !supported_platforms.contains(&(&*config.host_target.triple, true)))
     {
         return false;
     }
@@ -480,7 +480,7 @@ impl Step for Llvm {
         // https://llvm.org/docs/HowToCrossCompileLLVM.html
         if !builder.config.is_host_target(target) {
             let LlvmResult { llvm_config, .. } =
-                builder.ensure(Llvm { target: builder.config.build });
+                builder.ensure(Llvm { target: builder.config.host_target });
             if !builder.config.dry_run() {
                 let llvm_bindir =
                     command(&llvm_config).arg("--bindir").run_capture_stdout(builder).stdout();
@@ -494,7 +494,8 @@ impl Step for Llvm {
             }
             cfg.define("LLVM_CONFIG_PATH", llvm_config);
             if builder.config.llvm_clang {
-                let build_bin = builder.llvm_out(builder.config.build).join("build").join("bin");
+                let build_bin =
+                    builder.llvm_out(builder.config.host_target).join("build").join("bin");
                 let clang_tblgen = build_bin.join("clang-tblgen").with_extension(EXE_EXTENSION);
                 if !builder.config.dry_run() && !clang_tblgen.exists() {
                     panic!("unable to find {}", clang_tblgen.display());
@@ -628,7 +629,7 @@ fn configure_cmake(
     if builder.ninja() {
         cfg.generator("Ninja");
     }
-    cfg.target(&target.triple).host(&builder.config.build.triple);
+    cfg.target(&target.triple).host(&builder.config.host_target.triple);
 
     if !builder.config.is_host_target(target) {
         cfg.define("CMAKE_CROSSCOMPILING", "True");
@@ -813,7 +814,7 @@ fn configure_cmake(
         ldflags.push_all(flags);
     }
 
-    if let Some(flags) = get_var("LDFLAGS", &builder.config.build.triple, &target.triple) {
+    if let Some(flags) = get_var("LDFLAGS", &builder.config.host_target.triple, &target.triple) {
         ldflags.push_all(&flags);
     }
 
@@ -1135,7 +1136,8 @@ impl Step for Sanitizers {
             return runtimes;
         }
 
-        let LlvmResult { llvm_config, .. } = builder.ensure(Llvm { target: builder.config.build });
+        let LlvmResult { llvm_config, .. } =
+            builder.ensure(Llvm { target: builder.config.host_target });
 
         static STAMP_HASH_MEMO: OnceLock<String> = OnceLock::new();
         let smart_stamp_hash = STAMP_HASH_MEMO.get_or_init(|| {
@@ -1345,7 +1347,7 @@ impl Step for CrtBeginEnd {
         cfg.cargo_metadata(false)
             .out_dir(&out_dir)
             .target(&self.target.triple)
-            .host(&builder.config.build.triple)
+            .host(&builder.config.host_target.triple)
             .warnings(false)
             .debug(false)
             .opt_level(3)
@@ -1424,7 +1426,7 @@ impl Step for Libunwind {
                 cfg.archiver(ar);
             }
             cfg.target(&self.target.triple);
-            cfg.host(&builder.config.build.triple);
+            cfg.host(&builder.config.host_target.triple);
             cfg.warnings(false);
             cfg.debug(false);
             // get_compiler() need set opt_level first.
diff --git a/src/bootstrap/src/core/build_steps/perf.rs b/src/bootstrap/src/core/build_steps/perf.rs
index 14c7b7cf5e9..c43043b48f4 100644
--- a/src/bootstrap/src/core/build_steps/perf.rs
+++ b/src/bootstrap/src/core/build_steps/perf.rs
@@ -136,8 +136,8 @@ impl Display for Scenario {
 /// Performs profiling using `rustc-perf` on a built version of the compiler.
 pub fn perf(builder: &Builder<'_>, args: &PerfArgs) {
     let collector = builder.ensure(RustcPerf {
-        compiler: builder.compiler(0, builder.config.build),
-        target: builder.config.build,
+        compiler: builder.compiler(0, builder.config.host_target),
+        target: builder.config.host_target,
     });
 
     let is_profiling = match &args.cmd {
@@ -151,8 +151,8 @@ pub fn perf(builder: &Builder<'_>, args: &PerfArgs) {
 Consider setting `rust.debuginfo-level = 1` in `bootstrap.toml`."#);
     }
 
-    let compiler = builder.compiler(builder.top_stage, builder.config.build);
-    builder.ensure(Std::new(compiler, builder.config.build));
+    let compiler = builder.compiler(builder.top_stage, builder.config.host_target);
+    builder.ensure(Std::new(compiler, builder.config.host_target));
 
     if let Some(opts) = args.cmd.shared_opts()
         && opts.profiles.contains(&Profile::Doc)
diff --git a/src/bootstrap/src/core/build_steps/run.rs b/src/bootstrap/src/core/build_steps/run.rs
index 6ef1b13abcd..b3104ae05e8 100644
--- a/src/bootstrap/src/core/build_steps/run.rs
+++ b/src/bootstrap/src/core/build_steps/run.rs
@@ -116,7 +116,7 @@ impl Step for Miri {
     }
 
     fn run(self, builder: &Builder<'_>) {
-        let host = builder.build.build;
+        let host = builder.build.host_target;
         let target = self.target;
 
         // `x run` uses stage 0 by default but miri does not work well with stage 0.
@@ -448,7 +448,7 @@ impl Step for Rustfmt {
     }
 
     fn run(self, builder: &Builder<'_>) {
-        let host = builder.build.build;
+        let host = builder.build.host_target;
 
         // `x run` uses stage 0 by default but rustfmt does not work well with stage 0.
         // Change the stage to 1 if it's not set explicitly.
diff --git a/src/bootstrap/src/core/build_steps/setup.rs b/src/bootstrap/src/core/build_steps/setup.rs
index 25adfdf1601..86b7456d7b4 100644
--- a/src/bootstrap/src/core/build_steps/setup.rs
+++ b/src/bootstrap/src/core/build_steps/setup.rs
@@ -260,7 +260,7 @@ impl Step for Link {
         }
 
         let stage_path =
-            ["build", config.build.rustc_target_arg(), "stage1"].join(MAIN_SEPARATOR_STR);
+            ["build", config.host_target.rustc_target_arg(), "stage1"].join(MAIN_SEPARATOR_STR);
 
         if stage_dir_exists(&stage_path[..]) && !config.dry_run() {
             attempt_toolchain_link(builder, &stage_path[..]);
diff --git a/src/bootstrap/src/core/build_steps/test.rs b/src/bootstrap/src/core/build_steps/test.rs
index dddce8fe05d..419839067f9 100644
--- a/src/bootstrap/src/core/build_steps/test.rs
+++ b/src/bootstrap/src/core/build_steps/test.rs
@@ -70,7 +70,7 @@ impl Step for CrateBootstrap {
     }
 
     fn run(self, builder: &Builder<'_>) {
-        let bootstrap_host = builder.config.build;
+        let bootstrap_host = builder.config.host_target;
         let compiler = builder.compiler(0, bootstrap_host);
         let mut path = self.path.to_str().unwrap();
 
@@ -128,7 +128,7 @@ You can skip linkcheck with --skip src/tools/linkchecker"
         builder.info(&format!("Linkcheck ({host})"));
 
         // Test the linkchecker itself.
-        let bootstrap_host = builder.config.build;
+        let bootstrap_host = builder.config.host_target;
         let compiler = builder.compiler(0, bootstrap_host);
 
         let cargo = tool::prepare_tool_cargo(
@@ -525,7 +525,7 @@ impl Step for Miri {
 
     /// Runs `cargo test` for miri.
     fn run(self, builder: &Builder<'_>) {
-        let host = builder.build.build;
+        let host = builder.build.host_target;
         let target = self.target;
         let stage = builder.top_stage;
         if stage == 0 {
@@ -637,7 +637,7 @@ impl Step for CargoMiri {
 
     /// Tests `cargo miri test`.
     fn run(self, builder: &Builder<'_>) {
-        let host = builder.build.build;
+        let host = builder.build.host_target;
         let target = self.target;
         let stage = builder.top_stage;
         if stage == 0 {
@@ -915,7 +915,7 @@ impl Step for RustdocJSStd {
             Kind::Test,
             builder.top_stage,
             "rustdoc-js-std",
-            builder.config.build,
+            builder.config.host_target,
             self.target,
         );
         command.run(builder);
@@ -1607,7 +1607,7 @@ NOTE: if you're sure you want to do this, please open an issue as to why. In the
             // At stage 0 (stage - 1) we are using the stage0 compiler. Using `self.target` can lead
             // finding an incorrect compiler path on cross-targets, as the stage 0 is always equal to
             // `build.build` in the configuration.
-            let build = builder.build.build;
+            let build = builder.build.host_target;
             compiler = builder.compiler(compiler.stage - 1, build);
             let test_stage = compiler.stage + 1;
             (test_stage, format!("stage{test_stage}-{build}"))
@@ -1729,7 +1729,7 @@ NOTE: if you're sure you want to do this, please open an issue as to why. In the
         cmd.arg("--mode").arg(mode);
         cmd.arg("--target").arg(target.rustc_target_arg());
         cmd.arg("--host").arg(&*compiler.host.triple);
-        cmd.arg("--llvm-filecheck").arg(builder.llvm_filecheck(builder.config.build));
+        cmd.arg("--llvm-filecheck").arg(builder.llvm_filecheck(builder.config.host_target));
 
         if builder.build.config.llvm_enzyme {
             cmd.arg("--has-enzyme");
@@ -1900,7 +1900,7 @@ NOTE: if you're sure you want to do this, please open an issue as to why. In the
         let mut copts_passed = false;
         if builder.config.llvm_enabled(compiler.host) {
             let llvm::LlvmResult { llvm_config, .. } =
-                builder.ensure(llvm::Llvm { target: builder.config.build });
+                builder.ensure(llvm::Llvm { target: builder.config.host_target });
             if !builder.config.dry_run() {
                 let llvm_version = get_llvm_version(builder, &llvm_config);
                 let llvm_components =
@@ -1947,7 +1947,7 @@ NOTE: if you're sure you want to do this, please open an issue as to why. In the
                 // If LLD is available, add it to the PATH
                 if builder.config.lld_enabled {
                     let lld_install_root =
-                        builder.ensure(llvm::Lld { target: builder.config.build });
+                        builder.ensure(llvm::Lld { target: builder.config.host_target });
 
                     let lld_bin_path = lld_install_root.join("bin");
 
@@ -2009,7 +2009,7 @@ NOTE: if you're sure you want to do this, please open an issue as to why. In the
             // Note that if we encounter `PATH` we make sure to append to our own `PATH`
             // rather than stomp over it.
             if !builder.config.dry_run() && target.is_msvc() {
-                for (k, v) in builder.cc.borrow()[&target].env() {
+                for (k, v) in builder.cc[&target].env() {
                     if k != "PATH" {
                         cmd.env(k, v);
                     }
@@ -2026,8 +2026,7 @@ NOTE: if you're sure you want to do this, please open an issue as to why. In the
             // address sanitizer enabled (e.g., ntdll.dll).
             cmd.env("ASAN_WIN_CONTINUE_ON_INTERCEPTION_FAILURE", "1");
             // Add the address sanitizer runtime to the PATH - it is located next to cl.exe.
-            let asan_runtime_path =
-                builder.cc.borrow()[&target].path().parent().unwrap().to_path_buf();
+            let asan_runtime_path = builder.cc[&target].path().parent().unwrap().to_path_buf();
             let old_path = cmd
                 .get_envs()
                 .find_map(|(k, v)| (k == "PATH").then_some(v))
@@ -2202,7 +2201,7 @@ impl BookTest {
             let mut lib_paths = vec![];
             for dep in self.dependencies {
                 let mode = Mode::ToolRustc;
-                let target = builder.config.build;
+                let target = builder.config.host_target;
                 let cargo = tool::prepare_tool_cargo(
                     builder,
                     compiler,
@@ -2384,7 +2383,7 @@ impl Step for ErrorIndex {
         // error_index_generator depends on librustdoc. Use the compiler that
         // is normally used to build rustdoc for other tests (like compiletest
         // tests in tests/rustdoc) so that it shares the same artifacts.
-        let compiler = run.builder.compiler(run.builder.top_stage, run.builder.config.build);
+        let compiler = run.builder.compiler(run.builder.top_stage, run.builder.config.host_target);
         run.builder.ensure(ErrorIndex { compiler });
     }
 
@@ -2575,7 +2574,7 @@ fn prepare_cargo_test(
     // by `Cargo::new` and that actually makes things go wrong.
     if builder.kind != Kind::Miri {
         let mut dylib_paths = builder.rustc_lib_paths(compiler);
-        dylib_paths.push(PathBuf::from(&builder.sysroot_target_libdir(compiler, target)));
+        dylib_paths.push(builder.sysroot_target_libdir(compiler, target));
         helpers::add_dylib_path(dylib_paths, &mut cargo);
     }
 
@@ -2983,7 +2982,7 @@ impl Step for Distcheck {
             .arg("--enable-vendor")
             .current_dir(&dir)
             .run(builder);
-        command(helpers::make(&builder.config.build.triple))
+        command(helpers::make(&builder.config.host_target.triple))
             .arg("check")
             .current_dir(&dir)
             .run(builder);
@@ -3024,7 +3023,7 @@ impl Step for Bootstrap {
 
     /// Tests the build system itself.
     fn run(self, builder: &Builder<'_>) {
-        let host = builder.config.build;
+        let host = builder.config.host_target;
         let compiler = builder.compiler(0, host);
         let _guard = builder.msg(Kind::Test, 0, "bootstrap", host, host);
 
@@ -3035,7 +3034,7 @@ impl Step for Bootstrap {
         check_bootstrap
             .args(["-m", "unittest", "bootstrap_test.py"])
             .env("BUILD_DIR", &builder.out)
-            .env("BUILD_PLATFORM", builder.build.build.triple)
+            .env("BUILD_PLATFORM", builder.build.host_target.triple)
             .env("BOOTSTRAP_TEST_RUSTC_BIN", &builder.initial_rustc)
             .env("BOOTSTRAP_TEST_CARGO_BIN", &builder.initial_cargo)
             .current_dir(builder.src.join("src/bootstrap/"));
@@ -3059,6 +3058,8 @@ impl Step for Bootstrap {
         cargo
             .rustflag("-Cdebuginfo=2")
             .env("CARGO_TARGET_DIR", builder.out.join("bootstrap"))
+            // Needed for insta to correctly write pending snapshots to the right directories.
+            .env("INSTA_WORKSPACE_ROOT", &builder.src)
             .env("RUSTC_BOOTSTRAP", "1");
 
         // bootstrap tests are racy on directory creation so just run them one at a time.
@@ -3090,8 +3091,11 @@ impl Step for TierCheck {
     }
 
     fn make_run(run: RunConfig<'_>) {
-        let compiler =
-            run.builder.compiler_for(run.builder.top_stage, run.builder.build.build, run.target);
+        let compiler = run.builder.compiler_for(
+            run.builder.top_stage,
+            run.builder.build.host_target,
+            run.target,
+        );
         run.builder.ensure(TierCheck { compiler });
     }
 
@@ -3142,7 +3146,7 @@ impl Step for LintDocs {
 
     fn make_run(run: RunConfig<'_>) {
         run.builder.ensure(LintDocs {
-            compiler: run.builder.compiler(run.builder.top_stage, run.builder.config.build),
+            compiler: run.builder.compiler(run.builder.top_stage, run.builder.config.host_target),
             target: run.target,
         });
     }
@@ -3168,7 +3172,7 @@ impl Step for RustInstaller {
 
     /// Ensure the version placeholder replacement tool builds
     fn run(self, builder: &Builder<'_>) {
-        let bootstrap_host = builder.config.build;
+        let bootstrap_host = builder.config.host_target;
         let compiler = builder.compiler(0, bootstrap_host);
         let cargo = tool::prepare_tool_cargo(
             builder,
@@ -3270,7 +3274,7 @@ impl Step for TestHelpers {
         cfg.cargo_metadata(false)
             .out_dir(&dst)
             .target(&target.triple)
-            .host(&builder.config.build.triple)
+            .host(&builder.config.host_target.triple)
             .opt_level(0)
             .warnings(false)
             .debug(false)
@@ -3560,7 +3564,7 @@ impl Step for TestFloatParse {
     }
 
     fn run(self, builder: &Builder<'_>) {
-        let bootstrap_host = builder.config.build;
+        let bootstrap_host = builder.config.host_target;
         let compiler = builder.compiler(builder.top_stage, bootstrap_host);
         let path = self.path.to_str().unwrap();
         let crate_name = self.path.iter().next_back().unwrap().to_str().unwrap();
diff --git a/src/bootstrap/src/core/build_steps/tool.rs b/src/bootstrap/src/core/build_steps/tool.rs
index 9861637d8c8..0088e851d39 100644
--- a/src/bootstrap/src/core/build_steps/tool.rs
+++ b/src/bootstrap/src/core/build_steps/tool.rs
@@ -23,7 +23,6 @@ use crate::core::builder::{
     Builder, Cargo as CargoCommand, RunConfig, ShouldRun, Step, cargo_profile_var,
 };
 use crate::core::config::{DebuginfoLevel, RustcLto, TargetSelection};
-use crate::utils::channel::GitInfo;
 use crate::utils::exec::{BootstrapCommand, command};
 use crate::utils::helpers::{add_dylib_path, exe, t};
 use crate::{Compiler, FileType, Kind, Mode, gha};
@@ -137,6 +136,19 @@ impl Step for ToolBuild {
             _ => panic!("unexpected Mode for tool build"),
         }
 
+        // build.tool.TOOL_NAME.features in bootstrap.toml allows specifying which features to
+        // enable for a specific tool. `extra_features` instead is not controlled by the toml and
+        // provides features that are always enabled for a specific tool (e.g. "in-rust-tree" for
+        // rust-analyzer). Finally, `prepare_tool_cargo` might add more features to adapt the build
+        // to the chosen flags (e.g. "all-static" for cargo if `cargo_native_static` is true).
+        let mut features = builder
+            .config
+            .tool
+            .get(self.tool)
+            .and_then(|tool| tool.features.clone())
+            .unwrap_or_default();
+        features.extend(self.extra_features.clone());
+
         let mut cargo = prepare_tool_cargo(
             builder,
             self.compiler,
@@ -145,7 +157,7 @@ impl Step for ToolBuild {
             Kind::Build,
             path,
             self.source_type,
-            &self.extra_features,
+            &features,
         );
 
         // The stage0 compiler changes infrequently and does not directly depend on code
@@ -278,7 +290,7 @@ pub fn prepare_tool_cargo(
         cargo.env("CFG_VER_DESCRIPTION", description);
     }
 
-    let info = GitInfo::new(builder.config.omit_git_hash, &dir);
+    let info = builder.config.git_info(builder.config.omit_git_hash, &dir);
     if let Some(sha) = info.sha() {
         cargo.env("CFG_COMMIT_HASH", sha);
     }
@@ -342,14 +354,14 @@ pub(crate) fn get_tool_rustc_compiler(
 
     if builder.download_rustc() && target_compiler.stage == 1 {
         // We shouldn't drop to stage0 compiler when using CI rustc.
-        return builder.compiler(1, builder.config.build);
+        return builder.compiler(1, builder.config.host_target);
     }
 
     // Similar to `compile::Assemble`, build with the previous stage's compiler. Otherwise
     // we'd have stageN/bin/rustc and stageN/bin/$rustc_tool be effectively different stage
     // compilers, which isn't what we want. Rustc tools should be linked in the same way as the
     // compiler it's paired with, so it must be built with the previous stage compiler.
-    builder.compiler(target_compiler.stage.saturating_sub(1), builder.config.build)
+    builder.compiler(target_compiler.stage.saturating_sub(1), builder.config.host_target)
 }
 
 /// Links a built tool binary with the given `name` from the build directory to the
@@ -390,8 +402,8 @@ macro_rules! bootstrap_tool {
                 match tool {
                     $(Tool::$name =>
                         self.ensure($name {
-                            compiler: self.compiler(0, self.config.build),
-                            target: self.config.build,
+                            compiler: self.compiler(0, self.config.host_target),
+                            target: self.config.host_target,
                         }).tool_path,
                     )+
                 }
@@ -415,7 +427,7 @@ macro_rules! bootstrap_tool {
             fn make_run(run: RunConfig<'_>) {
                 run.builder.ensure($name {
                     // snapshot compiler
-                    compiler: run.builder.compiler(0, run.builder.config.build),
+                    compiler: run.builder.compiler(0, run.builder.config.host_target),
                     target: run.target,
                 });
             }
@@ -532,7 +544,7 @@ impl Step for RustcPerf {
 
     fn make_run(run: RunConfig<'_>) {
         run.builder.ensure(RustcPerf {
-            compiler: run.builder.compiler(0, run.builder.config.build),
+            compiler: run.builder.compiler(0, run.builder.config.host_target),
             target: run.target,
         });
     }
@@ -573,11 +585,11 @@ impl ErrorIndex {
     pub fn command(builder: &Builder<'_>) -> BootstrapCommand {
         // Error-index-generator links with the rustdoc library, so we need to add `rustc_lib_paths`
         // for rustc_private and libLLVM.so, and `sysroot_lib` for libstd, etc.
-        let host = builder.config.build;
+        let host = builder.config.host_target;
         let compiler = builder.compiler_for(builder.top_stage, host, host);
         let mut cmd = command(builder.ensure(ErrorIndex { compiler }).tool_path);
         let mut dylib_paths = builder.rustc_lib_paths(compiler);
-        dylib_paths.push(PathBuf::from(&builder.sysroot_target_libdir(compiler, compiler.host)));
+        dylib_paths.push(builder.sysroot_target_libdir(compiler, compiler.host));
         add_dylib_path(dylib_paths, &mut cmd);
         cmd
     }
@@ -596,7 +608,7 @@ impl Step for ErrorIndex {
         // src/tools/error-index-generator` which almost nobody does.
         // Normally, `x.py test` or `x.py doc` will use the
         // `ErrorIndex::command` function instead.
-        let compiler = run.builder.compiler(run.builder.top_stage, run.builder.config.build);
+        let compiler = run.builder.compiler(run.builder.top_stage, run.builder.config.host_target);
         run.builder.ensure(ErrorIndex { compiler });
     }
 
@@ -631,7 +643,7 @@ impl Step for RemoteTestServer {
 
     fn make_run(run: RunConfig<'_>) {
         run.builder.ensure(RemoteTestServer {
-            compiler: run.builder.compiler(run.builder.top_stage, run.builder.config.build),
+            compiler: run.builder.compiler(run.builder.top_stage, run.builder.config.host_target),
             target: run.target,
         });
     }
@@ -788,7 +800,7 @@ impl Step for Cargo {
 
     fn make_run(run: RunConfig<'_>) {
         run.builder.ensure(Cargo {
-            compiler: run.builder.compiler(run.builder.top_stage, run.builder.config.build),
+            compiler: run.builder.compiler(run.builder.top_stage, run.builder.config.host_target),
             target: run.target,
         });
     }
@@ -906,7 +918,7 @@ impl Step for RustAnalyzer {
 
     fn make_run(run: RunConfig<'_>) {
         run.builder.ensure(RustAnalyzer {
-            compiler: run.builder.compiler(run.builder.top_stage, run.builder.config.build),
+            compiler: run.builder.compiler(run.builder.top_stage, run.builder.config.host_target),
             target: run.target,
         });
     }
@@ -951,7 +963,7 @@ impl Step for RustAnalyzerProcMacroSrv {
 
     fn make_run(run: RunConfig<'_>) {
         run.builder.ensure(RustAnalyzerProcMacroSrv {
-            compiler: run.builder.compiler(run.builder.top_stage, run.builder.config.build),
+            compiler: run.builder.compiler(run.builder.top_stage, run.builder.config.host_target),
             target: run.target,
         });
     }
@@ -1004,7 +1016,7 @@ impl Step for LlvmBitcodeLinker {
 
     fn make_run(run: RunConfig<'_>) {
         run.builder.ensure(LlvmBitcodeLinker {
-            compiler: run.builder.compiler(run.builder.top_stage, run.builder.config.build),
+            compiler: run.builder.compiler(run.builder.top_stage, run.builder.config.host_target),
             extra_features: Vec::new(),
             target: run.target,
         });
@@ -1142,7 +1154,7 @@ macro_rules! tool_extended {
 
             fn make_run(run: RunConfig<'_>) {
                 run.builder.ensure($name {
-                    compiler: run.builder.compiler(run.builder.top_stage, run.builder.config.build),
+                    compiler: run.builder.compiler(run.builder.top_stage, run.builder.config.host_target),
                     target: run.target,
                 });
             }
@@ -1284,7 +1296,7 @@ impl Step for TestFloatParse {
     }
 
     fn run(self, builder: &Builder<'_>) -> ToolBuildResult {
-        let bootstrap_host = builder.config.build;
+        let bootstrap_host = builder.config.host_target;
         let compiler = builder.compiler(builder.top_stage, bootstrap_host);
 
         builder.ensure(ToolBuild {
@@ -1307,7 +1319,7 @@ impl Builder<'_> {
     /// `host`.
     pub fn tool_cmd(&self, tool: Tool) -> BootstrapCommand {
         let mut cmd = command(self.tool_exe(tool));
-        let compiler = self.compiler(0, self.config.build);
+        let compiler = self.compiler(0, self.config.host_target);
         let host = &compiler.host;
         // Prepares the `cmd` provided to be able to run the `compiler` provided.
         //
@@ -1322,7 +1334,7 @@ impl Builder<'_> {
         if compiler.host.is_msvc() {
             let curpaths = env::var_os("PATH").unwrap_or_default();
             let curpaths = env::split_paths(&curpaths).collect::<Vec<_>>();
-            for (k, v) in self.cc.borrow()[&compiler.host].env() {
+            for (k, v) in self.cc[&compiler.host].env() {
                 if k != "PATH" {
                     continue;
                 }
diff --git a/src/bootstrap/src/core/builder/cargo.rs b/src/bootstrap/src/core/builder/cargo.rs
index cf7f962d026..0e3c3aaee0f 100644
--- a/src/bootstrap/src/core/builder/cargo.rs
+++ b/src/bootstrap/src/core/builder/cargo.rs
@@ -278,9 +278,7 @@ impl Cargo {
             self.rustdocflags.arg(&arg);
         }
 
-        if !builder.config.dry_run()
-            && builder.cc.borrow()[&target].args().iter().any(|arg| arg == "-gz")
-        {
+        if !builder.config.dry_run() && builder.cc[&target].args().iter().any(|arg| arg == "-gz") {
             self.rustflags.arg("-Clink-arg=-gz");
         }
 
@@ -551,7 +549,7 @@ impl Builder<'_> {
         let libdir = self.rustc_libdir(compiler);
 
         let sysroot_str = sysroot.as_os_str().to_str().expect("sysroot should be UTF-8");
-        if self.is_verbose() && !matches!(self.config.dry_run, DryRun::SelfCheck) {
+        if self.is_verbose() && !matches!(self.config.get_dry_run(), DryRun::SelfCheck) {
             println!("using sysroot {sysroot_str}");
         }
 
diff --git a/src/bootstrap/src/core/builder/mod.rs b/src/bootstrap/src/core/builder/mod.rs
index 19b79bfe818..7433f0b0f3b 100644
--- a/src/bootstrap/src/core/builder/mod.rs
+++ b/src/bootstrap/src/core/builder/mod.rs
@@ -5,7 +5,7 @@ use std::fmt::{self, Debug, Write};
 use std::hash::Hash;
 use std::ops::Deref;
 use std::path::{Path, PathBuf};
-use std::sync::LazyLock;
+use std::sync::{LazyLock, OnceLock};
 use std::time::{Duration, Instant};
 use std::{env, fs};
 
@@ -22,6 +22,7 @@ use crate::core::config::flags::Subcommand;
 use crate::core::config::{DryRun, TargetSelection};
 use crate::utils::cache::Cache;
 use crate::utils::exec::{BootstrapCommand, command};
+use crate::utils::execution_context::ExecutionContext;
 use crate::utils::helpers::{self, LldThreads, add_dylib_path, exe, libdir, linker_args, t};
 use crate::{Build, Crate, trace};
 
@@ -59,6 +60,9 @@ pub struct Builder<'a> {
     /// to do. For example: with `./x check foo bar` we get `paths=["foo",
     /// "bar"]`.
     pub paths: Vec<PathBuf>,
+
+    /// Cached list of submodules from self.build.src.
+    submodule_paths_cache: OnceLock<Vec<String>>,
 }
 
 impl Deref for Builder<'_> {
@@ -136,7 +140,7 @@ pub struct RunConfig<'a> {
 
 impl RunConfig<'_> {
     pub fn build_triple(&self) -> TargetSelection {
-        self.builder.build.build
+        self.builder.build.host_target
     }
 
     /// Return a list of crate names selected by `run.paths`.
@@ -442,13 +446,15 @@ impl StepDescription {
 
     fn is_excluded(&self, builder: &Builder<'_>, pathset: &PathSet) -> bool {
         if builder.config.skip.iter().any(|e| pathset.has(e, builder.kind)) {
-            if !matches!(builder.config.dry_run, DryRun::SelfCheck) {
+            if !matches!(builder.config.get_dry_run(), DryRun::SelfCheck) {
                 println!("Skipping {pathset:?} because it is excluded");
             }
             return true;
         }
 
-        if !builder.config.skip.is_empty() && !matches!(builder.config.dry_run, DryRun::SelfCheck) {
+        if !builder.config.skip.is_empty()
+            && !matches!(builder.config.get_dry_run(), DryRun::SelfCheck)
+        {
             builder.verbose(|| {
                 println!(
                     "{:?} not skipped for {:?} -- not in {:?}",
@@ -684,7 +690,7 @@ impl<'a> ShouldRun<'a> {
     ///
     /// [`path`]: ShouldRun::path
     pub fn paths(mut self, paths: &[&str]) -> Self {
-        let submodules_paths = build_helper::util::parse_gitmodules(&self.builder.src);
+        let submodules_paths = self.builder.submodule_paths();
 
         self.paths.insert(PathSet::Set(
             paths
@@ -1177,6 +1183,7 @@ impl<'a> Builder<'a> {
             stack: RefCell::new(Vec::new()),
             time_spent_on_dependencies: Cell::new(Duration::new(0, 0)),
             paths,
+            submodule_paths_cache: Default::default(),
         }
     }
 
@@ -1294,10 +1301,10 @@ impl<'a> Builder<'a> {
     ) -> Compiler {
         let mut resolved_compiler = if self.build.force_use_stage2(stage) {
             trace!(target: "COMPILER_FOR", ?stage, "force_use_stage2");
-            self.compiler(2, self.config.build)
+            self.compiler(2, self.config.host_target)
         } else if self.build.force_use_stage1(stage, target) {
             trace!(target: "COMPILER_FOR", ?stage, "force_use_stage1");
-            self.compiler(1, self.config.build)
+            self.compiler(1, self.config.host_target)
         } else {
             trace!(target: "COMPILER_FOR", ?stage, ?host, "no force, fallback to `compiler()`");
             self.compiler(stage, host)
@@ -1355,7 +1362,7 @@ impl<'a> Builder<'a> {
     /// Windows.
     pub fn libdir_relative(&self, compiler: Compiler) -> &Path {
         if compiler.is_snapshot(self) {
-            libdir(self.config.build).as_ref()
+            libdir(self.config.host_target).as_ref()
         } else {
             match self.config.libdir_relative() {
                 Some(relative_libdir) if compiler.stage >= 1 => relative_libdir,
@@ -1436,9 +1443,10 @@ impl<'a> Builder<'a> {
             return cmd;
         }
 
-        let _ = self.ensure(tool::Clippy { compiler: run_compiler, target: self.build.build });
-        let cargo_clippy =
-            self.ensure(tool::CargoClippy { compiler: run_compiler, target: self.build.build });
+        let _ =
+            self.ensure(tool::Clippy { compiler: run_compiler, target: self.build.host_target });
+        let cargo_clippy = self
+            .ensure(tool::CargoClippy { compiler: run_compiler, target: self.build.host_target });
         let mut dylib_path = helpers::dylib_path();
         dylib_path.insert(0, self.sysroot(run_compiler).join("lib"));
 
@@ -1451,9 +1459,10 @@ impl<'a> Builder<'a> {
     pub fn cargo_miri_cmd(&self, run_compiler: Compiler) -> BootstrapCommand {
         assert!(run_compiler.stage > 0, "miri can not be invoked at stage 0");
         // Prepare the tools
-        let miri = self.ensure(tool::Miri { compiler: run_compiler, target: self.build.build });
+        let miri =
+            self.ensure(tool::Miri { compiler: run_compiler, target: self.build.host_target });
         let cargo_miri =
-            self.ensure(tool::CargoMiri { compiler: run_compiler, target: self.build.build });
+            self.ensure(tool::CargoMiri { compiler: run_compiler, target: self.build.host_target });
         // Invoke cargo-miri, make sure it can find miri and cargo.
         let mut cmd = command(cargo_miri.tool_path);
         cmd.env("MIRI", &miri.tool_path);
@@ -1505,6 +1514,19 @@ impl<'a> Builder<'a> {
         None
     }
 
+    /// Updates all submodules, and exits with an error if submodule
+    /// management is disabled and the submodule does not exist.
+    pub fn require_and_update_all_submodules(&self) {
+        for submodule in self.submodule_paths() {
+            self.require_submodule(submodule, None);
+        }
+    }
+
+    /// Get all submodules from the src directory.
+    pub fn submodule_paths(&self) -> &[String] {
+        self.submodule_paths_cache.get_or_init(|| build_helper::util::parse_gitmodules(&self.src))
+    }
+
     /// Ensure that a given step is built, returning its output. This will
     /// cache the step, so it is safe (and good!) to call this as often as
     /// needed to ensure that all dependencies are built.
@@ -1633,4 +1655,14 @@ impl<'a> Builder<'a> {
             self.info(&format!("{err}\n"));
         }
     }
+
+    pub fn exec_ctx(&self) -> &ExecutionContext {
+        &self.config.exec_ctx
+    }
+}
+
+impl<'a> AsRef<ExecutionContext> for Builder<'a> {
+    fn as_ref(&self) -> &ExecutionContext {
+        self.exec_ctx()
+    }
 }
diff --git a/src/bootstrap/src/core/builder/tests.rs b/src/bootstrap/src/core/builder/tests.rs
index baa22fc7f72..d07df7f4a84 100644
--- a/src/bootstrap/src/core/builder/tests.rs
+++ b/src/bootstrap/src/core/builder/tests.rs
@@ -15,14 +15,15 @@ static TEST_TRIPLE_2: &str = "i686-unknown-hurd-gnu";
 static TEST_TRIPLE_3: &str = "i686-unknown-netbsd";
 
 fn configure(cmd: &str, host: &[&str], target: &[&str]) -> Config {
-    configure_with_args(&[cmd.to_owned()], host, target)
+    configure_with_args(&[cmd], host, target)
 }
 
-fn configure_with_args(cmd: &[String], host: &[&str], target: &[&str]) -> Config {
-    let mut config = Config::parse(Flags::parse(cmd));
+fn configure_with_args(cmd: &[&str], host: &[&str], target: &[&str]) -> Config {
+    let cmd = cmd.iter().copied().map(String::from).collect::<Vec<_>>();
+    let mut config = Config::parse(Flags::parse(&cmd));
     // don't save toolstates
     config.save_toolstates = None;
-    config.dry_run = DryRun::SelfCheck;
+    config.set_dry_run(DryRun::SelfCheck);
 
     // Ignore most submodules, since we don't need them for a dry run, and the
     // tests run much faster without them.
@@ -46,7 +47,7 @@ fn configure_with_args(cmd: &[String], host: &[&str], target: &[&str]) -> Config
         .join(&thread::current().name().unwrap_or("unknown").replace(":", "-"));
     t!(fs::create_dir_all(&dir));
     config.out = dir;
-    config.build = TargetSelection::from_user(TEST_TRIPLE_1);
+    config.host_target = TargetSelection::from_user(TEST_TRIPLE_1);
     config.hosts = host.iter().map(|s| TargetSelection::from_user(s)).collect();
     config.targets = target.iter().map(|s| TargetSelection::from_user(s)).collect();
     config
@@ -67,7 +68,7 @@ fn run_build(paths: &[PathBuf], config: Config) -> Cache {
 fn check_cli<const N: usize>(paths: [&str; N]) {
     run_build(
         &paths.map(PathBuf::from),
-        configure_with_args(&paths.map(String::from), &[TEST_TRIPLE_1], &[TEST_TRIPLE_1]),
+        configure_with_args(&paths, &[TEST_TRIPLE_1], &[TEST_TRIPLE_1]),
     );
 }
 
@@ -1000,8 +1001,7 @@ mod sysroot_target_dirs {
 /// cg_gcc tests instead.
 #[test]
 fn test_test_compiler() {
-    let cmd = &["test", "compiler"].map(str::to_owned);
-    let config = configure_with_args(cmd, &[TEST_TRIPLE_1], &[TEST_TRIPLE_1]);
+    let config = configure_with_args(&["test", "compiler"], &[TEST_TRIPLE_1], &[TEST_TRIPLE_1]);
     let cache = run_build(&config.paths.clone(), config);
 
     let compiler = cache.contains::<test::CrateLibrustc>();
@@ -1034,8 +1034,7 @@ fn test_test_coverage() {
         // Print each test case so that if one fails, the most recently printed
         // case is the one that failed.
         println!("Testing case: {cmd:?}");
-        let cmd = cmd.iter().copied().map(str::to_owned).collect::<Vec<_>>();
-        let config = configure_with_args(&cmd, &[TEST_TRIPLE_1], &[TEST_TRIPLE_1]);
+        let config = configure_with_args(cmd, &[TEST_TRIPLE_1], &[TEST_TRIPLE_1]);
         let mut cache = run_build(&config.paths.clone(), config);
 
         let modes =
@@ -1102,7 +1101,7 @@ fn test_prebuilt_llvm_config_path_resolution() {
     let actual = drop_win_disk_prefix_if_present(actual);
     assert_eq!(expected, actual);
 
-    let actual = prebuilt_llvm_config(&builder, builder.config.build, false)
+    let actual = prebuilt_llvm_config(&builder, builder.config.host_target, false)
         .llvm_result()
         .llvm_config
         .clone();
@@ -1120,15 +1119,15 @@ fn test_prebuilt_llvm_config_path_resolution() {
     let build = Build::new(config.clone());
     let builder = Builder::new(&build);
 
-    let actual = prebuilt_llvm_config(&builder, builder.config.build, false)
+    let actual = prebuilt_llvm_config(&builder, builder.config.host_target, false)
         .llvm_result()
         .llvm_config
         .clone();
     let expected = builder
         .out
-        .join(builder.config.build)
+        .join(builder.config.host_target)
         .join("llvm/bin")
-        .join(exe("llvm-config", builder.config.build));
+        .join(exe("llvm-config", builder.config.host_target));
     assert_eq!(expected, actual);
 
     let config = configure(
@@ -1143,15 +1142,15 @@ fn test_prebuilt_llvm_config_path_resolution() {
         let build = Build::new(config.clone());
         let builder = Builder::new(&build);
 
-        let actual = prebuilt_llvm_config(&builder, builder.config.build, false)
+        let actual = prebuilt_llvm_config(&builder, builder.config.host_target, false)
             .llvm_result()
             .llvm_config
             .clone();
         let expected = builder
             .out
-            .join(builder.config.build)
+            .join(builder.config.host_target)
             .join("ci-llvm/bin")
-            .join(exe("llvm-config", builder.config.build));
+            .join(exe("llvm-config", builder.config.host_target));
         assert_eq!(expected, actual);
     }
 }
@@ -1163,7 +1162,7 @@ fn test_is_builder_target() {
 
     for (target1, target2) in [(target1, target2), (target2, target1)] {
         let mut config = configure("build", &[], &[]);
-        config.build = target1;
+        config.host_target = target1;
         let build = Build::new(config);
         let builder = Builder::new(&build);
 
@@ -1207,8 +1206,7 @@ fn test_get_tool_rustc_compiler() {
 /// of `Any { .. }`.
 #[test]
 fn step_cycle_debug() {
-    let cmd = ["run", "cyclic-step"].map(str::to_owned);
-    let config = configure_with_args(&cmd, &[TEST_TRIPLE_1], &[TEST_TRIPLE_1]);
+    let config = configure_with_args(&["run", "cyclic-step"], &[TEST_TRIPLE_1], &[TEST_TRIPLE_1]);
 
     let err = panic::catch_unwind(|| run_build(&config.paths.clone(), config)).unwrap_err();
     let err = err.downcast_ref::<String>().unwrap().as_str();
@@ -1233,3 +1231,81 @@ fn any_debug() {
     // Downcasting to the underlying type should succeed.
     assert_eq!(x.downcast_ref::<MyStruct>(), Some(&MyStruct { x: 7 }));
 }
+
+/// The staging tests use insta for snapshot testing.
+/// See bootstrap's README on how to bless the snapshots.
+mod staging {
+    use crate::core::builder::tests::{
+        TEST_TRIPLE_1, configure, configure_with_args, render_steps, run_build,
+    };
+
+    #[test]
+    fn build_compiler_stage_1() {
+        let mut cache = run_build(
+            &["compiler".into()],
+            configure_with_args(&["build", "--stage", "1"], &[TEST_TRIPLE_1], &[TEST_TRIPLE_1]),
+        );
+        let steps = cache.into_executed_steps();
+        insta::assert_snapshot!(render_steps(&steps), @r"
+        [build] rustc 0 <target1> -> std 0 <target1>
+        [build] llvm <target1>
+        [build] rustc 0 <target1> -> rustc 1 <target1>
+        [build] rustc 0 <target1> -> rustc 1 <target1>
+        ");
+    }
+}
+
+/// Renders the executed bootstrap steps for usage in snapshot tests with insta.
+/// Only renders certain important steps.
+/// Each value in `steps` should be a tuple of (Step, step output).
+fn render_steps(steps: &[(Box<dyn Any>, Box<dyn Any>)]) -> String {
+    steps
+        .iter()
+        .filter_map(|(step, output)| {
+            // FIXME: implement an optional method on Step to produce metadata for test, instead
+            // of this downcasting
+            if let Some((rustc, output)) = downcast_step::<compile::Rustc>(step, output) {
+                Some(format!(
+                    "[build] {} -> {}",
+                    render_compiler(rustc.build_compiler),
+                    // FIXME: return the correct stage from the `Rustc` step, now it behaves weirdly
+                    render_compiler(Compiler::new(rustc.build_compiler.stage + 1, rustc.target)),
+                ))
+            } else if let Some((std, output)) = downcast_step::<compile::Std>(step, output) {
+                Some(format!(
+                    "[build] {} -> std {} <{}>",
+                    render_compiler(std.compiler),
+                    std.compiler.stage,
+                    std.target
+                ))
+            } else if let Some((llvm, output)) = downcast_step::<llvm::Llvm>(step, output) {
+                Some(format!("[build] llvm <{}>", llvm.target))
+            } else {
+                None
+            }
+        })
+        .map(|line| {
+            line.replace(TEST_TRIPLE_1, "target1")
+                .replace(TEST_TRIPLE_2, "target2")
+                .replace(TEST_TRIPLE_3, "target3")
+        })
+        .collect::<Vec<_>>()
+        .join("\n")
+}
+
+fn downcast_step<'a, S: Step>(
+    step: &'a Box<dyn Any>,
+    output: &'a Box<dyn Any>,
+) -> Option<(&'a S, &'a S::Output)> {
+    let Some(step) = step.downcast_ref::<S>() else {
+        return None;
+    };
+    let Some(output) = output.downcast_ref::<S::Output>() else {
+        return None;
+    };
+    Some((step, output))
+}
+
+fn render_compiler(compiler: Compiler) -> String {
+    format!("rustc {} <{}>", compiler.stage, compiler.host)
+}
diff --git a/src/bootstrap/src/core/config/config.rs b/src/bootstrap/src/core/config/config.rs
index a92d58ef9e8..f9980ac5fe1 100644
--- a/src/bootstrap/src/core/config/config.rs
+++ b/src/bootstrap/src/core/config/config.rs
@@ -24,7 +24,7 @@ use std::{cmp, env, fs};
 
 use build_helper::ci::CiEnv;
 use build_helper::exit;
-use build_helper::git::{GitConfig, PathFreshness, check_path_modifications, output_result};
+use build_helper::git::{GitConfig, PathFreshness, check_path_modifications};
 use serde::Deserialize;
 #[cfg(feature = "tracing")]
 use tracing::{instrument, span};
@@ -35,7 +35,7 @@ pub use crate::core::config::flags::Subcommand;
 use crate::core::config::flags::{Color, Flags};
 use crate::core::config::target_selection::TargetSelectionList;
 use crate::core::config::toml::TomlConfig;
-use crate::core::config::toml::build::Build;
+use crate::core::config::toml::build::{Build, Tool};
 use crate::core::config::toml::change_id::ChangeId;
 use crate::core::config::toml::rust::{
     LldMode, RustOptimize, check_incompatible_options_for_ci_rustc,
@@ -47,8 +47,10 @@ use crate::core::config::{
 };
 use crate::core::download::is_download_ci_available;
 use crate::utils::channel;
+use crate::utils::exec::command;
+use crate::utils::execution_context::ExecutionContext;
 use crate::utils::helpers::exe;
-use crate::{Command, GitInfo, OnceLock, TargetSelection, check_ci_llvm, helpers, output, t};
+use crate::{GitInfo, OnceLock, TargetSelection, check_ci_llvm, helpers, t};
 
 /// Each path in this list is considered "allowed" in the `download-rustc="if-unchanged"` logic.
 /// This means they can be modified and changes to these paths should never trigger a compiler build
@@ -99,6 +101,9 @@ pub struct Config {
     pub bootstrap_cache_path: Option<PathBuf>,
     pub extended: bool,
     pub tools: Option<HashSet<String>>,
+    /// Specify build configuration specific for some tool, such as enabled features, see [Tool].
+    /// The key in the map is the name of the tool, and the value is tool-specific configuration.
+    pub tool: HashMap<String, Tool>,
     pub sanitizers: bool,
     pub profiler: bool,
     pub omit_git_hash: bool,
@@ -129,7 +134,6 @@ pub struct Config {
     pub jobs: Option<u32>,
     pub cmd: Subcommand,
     pub incremental: bool,
-    pub dry_run: DryRun,
     pub dump_bootstrap_shims: bool,
     /// Arguments appearing after `--` to be forwarded to tools,
     /// e.g. `--fix-broken` or test arguments.
@@ -220,7 +224,7 @@ pub struct Config {
 
     pub reproducible_artifacts: Vec<String>,
 
-    pub build: TargetSelection,
+    pub host_target: TargetSelection,
     pub hosts: Vec<TargetSelection>,
     pub targets: Vec<TargetSelection>,
     pub local_rebuild: bool,
@@ -304,6 +308,8 @@ pub struct Config {
     /// This is mostly for RA as building the stage1 compiler to check the library tree
     /// on each code change might be too much for some computers.
     pub skip_std_check_if_no_download_rustc: bool,
+
+    pub exec_ctx: ExecutionContext,
 }
 
 impl Config {
@@ -343,7 +349,7 @@ impl Config {
             stderr_is_tty: std::io::stderr().is_terminal(),
 
             // set by build.rs
-            build: TargetSelection::from_user(env!("BUILD_TRIPLE")),
+            host_target: TargetSelection::from_user(env!("BUILD_TRIPLE")),
 
             src: {
                 let manifest_dir = PathBuf::from(env!("CARGO_MANIFEST_DIR"));
@@ -360,6 +366,14 @@ impl Config {
         }
     }
 
+    pub fn set_dry_run(&mut self, dry_run: DryRun) {
+        self.exec_ctx.set_dry_run(dry_run);
+    }
+
+    pub fn get_dry_run(&self) -> &DryRun {
+        self.exec_ctx.get_dry_run()
+    }
+
     #[cfg_attr(
         feature = "tracing",
         instrument(target = "CONFIG_HANDLING", level = "trace", name = "Config::parse", skip_all)
@@ -382,6 +396,11 @@ impl Config {
         get_toml: impl Fn(&Path) -> Result<TomlConfig, toml::de::Error>,
     ) -> Config {
         let mut config = Config::default_opts();
+        let mut exec_ctx = ExecutionContext::new();
+        exec_ctx.set_verbose(flags.verbose);
+        exec_ctx.set_fail_fast(flags.cmd.fail_fast());
+
+        config.exec_ctx = exec_ctx;
 
         // Set flags.
         config.paths = std::mem::take(&mut flags.paths);
@@ -410,7 +429,7 @@ impl Config {
         config.on_fail = flags.on_fail;
         config.cmd = flags.cmd;
         config.incremental = flags.incremental;
-        config.dry_run = if flags.dry_run { DryRun::UserSelected } else { DryRun::Disabled };
+        config.set_dry_run(if flags.dry_run { DryRun::UserSelected } else { DryRun::Disabled });
         config.dump_bootstrap_shims = flags.dump_bootstrap_shims;
         config.keep_stage = flags.keep_stage;
         config.keep_stage_std = flags.keep_stage_std;
@@ -440,14 +459,9 @@ impl Config {
             // has already been (kinda-cross-)compiled to Windows land, we require a normal Windows path.
             cmd.arg("rev-parse").arg("--show-cdup");
             // Discard stderr because we expect this to fail when building from a tarball.
-            let output = cmd
-                .as_command_mut()
-                .stderr(std::process::Stdio::null())
-                .output()
-                .ok()
-                .and_then(|output| if output.status.success() { Some(output) } else { None });
-            if let Some(output) = output {
-                let git_root_relative = String::from_utf8(output.stdout).unwrap();
+            let output = cmd.allow_failure().run_capture_stdout(&config);
+            if output.is_success() {
+                let git_root_relative = output.stdout();
                 // We need to canonicalize this path to make sure it uses backslashes instead of forward slashes,
                 // and to resolve any relative components.
                 let git_root = env::current_dir()
@@ -542,7 +556,7 @@ impl Config {
             build.cargo = build.cargo.take().or(std::env::var_os("CARGO").map(|p| p.into()));
         }
 
-        if GitInfo::new(false, &config.src).is_from_tarball() && toml.profile.is_none() {
+        if config.git_info(false, &config.src).is_from_tarball() && toml.profile.is_none() {
             toml.profile = Some("dist".into());
         }
 
@@ -665,6 +679,7 @@ impl Config {
             bootstrap_cache_path,
             extended,
             tools,
+            tool,
             verbose,
             sanitizers,
             profiler,
@@ -716,7 +731,7 @@ impl Config {
         config.jobs = Some(threads_from_config(flags.jobs.unwrap_or(jobs.unwrap_or(0))));
 
         if let Some(file_build) = build {
-            config.build = TargetSelection::from_user(&file_build);
+            config.host_target = TargetSelection::from_user(&file_build);
         };
 
         set(&mut config.out, flags.build_dir.or_else(|| build_dir.map(PathBuf::from)));
@@ -742,14 +757,19 @@ impl Config {
             config.download_beta_toolchain();
             config
                 .out
-                .join(config.build)
+                .join(config.host_target)
                 .join("stage0")
                 .join("bin")
-                .join(exe("rustc", config.build))
+                .join(exe("rustc", config.host_target))
         };
 
         config.initial_sysroot = t!(PathBuf::from_str(
-            output(Command::new(&config.initial_rustc).args(["--print", "sysroot"])).trim()
+            command(&config.initial_rustc)
+                .args(["--print", "sysroot"])
+                .run_always()
+                .run_capture_stdout(&config)
+                .stdout()
+                .trim()
         ));
 
         config.initial_cargo_clippy = cargo_clippy;
@@ -761,7 +781,7 @@ impl Config {
             cargo
         } else {
             config.download_beta_toolchain();
-            config.initial_sysroot.join("bin").join(exe("cargo", config.build))
+            config.initial_sysroot.join("bin").join(exe("cargo", config.host_target))
         };
 
         // NOTE: it's important this comes *after* we set `initial_rustc` just above.
@@ -776,7 +796,7 @@ impl Config {
         } else if let Some(file_host) = host {
             file_host.iter().map(|h| TargetSelection::from_user(h)).collect()
         } else {
-            vec![config.build]
+            vec![config.host_target]
         };
         config.targets = if let Some(TargetSelectionList(arg_target)) = flags.target {
             arg_target
@@ -806,6 +826,7 @@ impl Config {
         set(&mut config.full_bootstrap, full_bootstrap);
         set(&mut config.extended, extended);
         config.tools = tools;
+        set(&mut config.tool, tool);
         set(&mut config.verbose, verbose);
         set(&mut config.sanitizers, sanitizers);
         set(&mut config.profiler, profiler);
@@ -845,19 +866,21 @@ impl Config {
         let default = config.channel == "dev";
         config.omit_git_hash = toml.rust.as_ref().and_then(|r| r.omit_git_hash).unwrap_or(default);
 
-        config.rust_info = GitInfo::new(config.omit_git_hash, &config.src);
-        config.cargo_info = GitInfo::new(config.omit_git_hash, &config.src.join("src/tools/cargo"));
+        config.rust_info = config.git_info(config.omit_git_hash, &config.src);
+        config.cargo_info =
+            config.git_info(config.omit_git_hash, &config.src.join("src/tools/cargo"));
         config.rust_analyzer_info =
-            GitInfo::new(config.omit_git_hash, &config.src.join("src/tools/rust-analyzer"));
+            config.git_info(config.omit_git_hash, &config.src.join("src/tools/rust-analyzer"));
         config.clippy_info =
-            GitInfo::new(config.omit_git_hash, &config.src.join("src/tools/clippy"));
-        config.miri_info = GitInfo::new(config.omit_git_hash, &config.src.join("src/tools/miri"));
+            config.git_info(config.omit_git_hash, &config.src.join("src/tools/clippy"));
+        config.miri_info =
+            config.git_info(config.omit_git_hash, &config.src.join("src/tools/miri"));
         config.rustfmt_info =
-            GitInfo::new(config.omit_git_hash, &config.src.join("src/tools/rustfmt"));
+            config.git_info(config.omit_git_hash, &config.src.join("src/tools/rustfmt"));
         config.enzyme_info =
-            GitInfo::new(config.omit_git_hash, &config.src.join("src/tools/enzyme"));
-        config.in_tree_llvm_info = GitInfo::new(false, &config.src.join("src/llvm-project"));
-        config.in_tree_gcc_info = GitInfo::new(false, &config.src.join("src/gcc"));
+            config.git_info(config.omit_git_hash, &config.src.join("src/tools/enzyme"));
+        config.in_tree_llvm_info = config.git_info(false, &config.src.join("src/llvm-project"));
+        config.in_tree_gcc_info = config.git_info(false, &config.src.join("src/gcc"));
 
         config.vendor = vendor.unwrap_or(
             config.rust_info.is_from_tarball()
@@ -908,17 +931,19 @@ impl Config {
         }
 
         if config.llvm_from_ci {
-            let triple = &config.build.triple;
+            let triple = &config.host_target.triple;
             let ci_llvm_bin = config.ci_llvm_root().join("bin");
             let build_target = config
                 .target_config
-                .entry(config.build)
+                .entry(config.host_target)
                 .or_insert_with(|| Target::from_triple(triple));
 
             check_ci_llvm!(build_target.llvm_config);
             check_ci_llvm!(build_target.llvm_filecheck);
-            build_target.llvm_config = Some(ci_llvm_bin.join(exe("llvm-config", config.build)));
-            build_target.llvm_filecheck = Some(ci_llvm_bin.join(exe("FileCheck", config.build)));
+            build_target.llvm_config =
+                Some(ci_llvm_bin.join(exe("llvm-config", config.host_target)));
+            build_target.llvm_filecheck =
+                Some(ci_llvm_bin.join(exe("FileCheck", config.host_target)));
         }
 
         config.apply_dist_config(toml.dist);
@@ -935,7 +960,7 @@ impl Config {
             );
         }
 
-        if config.lld_enabled && config.is_system_llvm(config.build) {
+        if config.lld_enabled && config.is_system_llvm(config.host_target) {
             eprintln!(
                 "Warning: LLD is enabled when using external llvm-config. LLD will not be built and copied to the sysroot."
             );
@@ -1017,28 +1042,13 @@ impl Config {
     }
 
     pub fn dry_run(&self) -> bool {
-        match self.dry_run {
-            DryRun::Disabled => false,
-            DryRun::SelfCheck | DryRun::UserSelected => true,
-        }
+        self.exec_ctx.dry_run()
     }
 
     pub fn is_explicit_stage(&self) -> bool {
         self.explicit_stage_from_cli || self.explicit_stage_from_config
     }
 
-    /// Runs a command, printing out nice contextual information if it fails.
-    /// Exits if the command failed to execute at all, otherwise returns its
-    /// `status.success()`.
-    #[deprecated = "use `Builder::try_run` instead where possible"]
-    pub(crate) fn try_run(&self, cmd: &mut Command) -> Result<(), ()> {
-        if self.dry_run() {
-            return Ok(());
-        }
-        self.verbose(|| println!("running: {cmd:?}"));
-        build_helper::util::try_run(cmd, self.is_verbose())
-    }
-
     pub(crate) fn test_args(&self) -> Vec<&str> {
         let mut test_args = match self.cmd {
             Subcommand::Test { ref test_args, .. }
@@ -1072,7 +1082,7 @@ impl Config {
 
         let mut git = helpers::git(Some(&self.src));
         git.arg("show").arg(format!("{commit}:{}", file.to_str().unwrap()));
-        output(git.as_command_mut())
+        git.run_capture_stdout(self).stdout()
     }
 
     /// Bootstrap embeds a version number into the name of shared libraries it uploads in CI.
@@ -1144,13 +1154,13 @@ impl Config {
     /// The absolute path to the downloaded LLVM artifacts.
     pub(crate) fn ci_llvm_root(&self) -> PathBuf {
         assert!(self.llvm_from_ci);
-        self.out.join(self.build).join("ci-llvm")
+        self.out.join(self.host_target).join("ci-llvm")
     }
 
     /// Directory where the extracted `rustc-dev` component is stored.
     pub(crate) fn ci_rustc_dir(&self) -> PathBuf {
         assert!(self.download_rustc());
-        self.out.join(self.build).join("ci-rustc")
+        self.out.join(self.host_target).join("ci-rustc")
     }
 
     /// Determine whether llvm should be linked dynamically.
@@ -1234,7 +1244,7 @@ impl Config {
                         // Check the config compatibility
                         // FIXME: this doesn't cover `--set` flags yet.
                         let res = check_incompatible_options_for_ci_rustc(
-                            self.build,
+                            self.host_target,
                             current_config_toml,
                             ci_config_toml,
                         );
@@ -1260,9 +1270,7 @@ impl Config {
 
     /// Runs a function if verbosity is greater than 0
     pub fn verbose(&self, f: impl Fn()) {
-        if self.is_verbose() {
-            f()
-        }
+        self.exec_ctx.verbose(f);
     }
 
     pub fn any_sanitizers_to_build(&self) -> bool {
@@ -1324,7 +1332,7 @@ impl Config {
 
         // NOTE: The check for the empty directory is here because when running x.py the first time,
         // the submodule won't be checked out. Check it out now so we can build it.
-        if !GitInfo::new(false, &absolute_path).is_managed_git_subrepository()
+        if !self.git_info(false, &absolute_path).is_managed_git_subrepository()
             && !helpers::dir_is_empty(&absolute_path)
         {
             return;
@@ -1343,16 +1351,16 @@ impl Config {
         };
 
         // Determine commit checked out in submodule.
-        let checked_out_hash = output(submodule_git().args(["rev-parse", "HEAD"]).as_command_mut());
+        let checked_out_hash =
+            submodule_git().args(["rev-parse", "HEAD"]).run_capture_stdout(self).stdout();
         let checked_out_hash = checked_out_hash.trim_end();
         // Determine commit that the submodule *should* have.
-        let recorded = output(
-            helpers::git(Some(&self.src))
-                .run_always()
-                .args(["ls-tree", "HEAD"])
-                .arg(relative_path)
-                .as_command_mut(),
-        );
+        let recorded = helpers::git(Some(&self.src))
+            .run_always()
+            .args(["ls-tree", "HEAD"])
+            .arg(relative_path)
+            .run_capture_stdout(self)
+            .stdout();
 
         let actual_hash = recorded
             .split_whitespace()
@@ -1365,32 +1373,32 @@ impl Config {
         }
 
         println!("Updating submodule {relative_path}");
-        self.check_run(
-            helpers::git(Some(&self.src))
-                .run_always()
-                .args(["submodule", "-q", "sync"])
-                .arg(relative_path),
-        );
+
+        helpers::git(Some(&self.src))
+            .allow_failure()
+            .run_always()
+            .args(["submodule", "-q", "sync"])
+            .arg(relative_path)
+            .run(self);
 
         // Try passing `--progress` to start, then run git again without if that fails.
         let update = |progress: bool| {
             // Git is buggy and will try to fetch submodules from the tracking branch for *this* repository,
             // even though that has no relation to the upstream for the submodule.
-            let current_branch = output_result(
-                helpers::git(Some(&self.src))
-                    .allow_failure()
-                    .run_always()
-                    .args(["symbolic-ref", "--short", "HEAD"])
-                    .as_command_mut(),
-            )
-            .map(|b| b.trim().to_owned());
+            let current_branch = helpers::git(Some(&self.src))
+                .allow_failure()
+                .run_always()
+                .args(["symbolic-ref", "--short", "HEAD"])
+                .run_capture(self);
 
             let mut git = helpers::git(Some(&self.src)).allow_failure();
             git.run_always();
-            if let Ok(branch) = current_branch {
+            if current_branch.is_success() {
                 // If there is a tag named after the current branch, git will try to disambiguate by prepending `heads/` to the branch name.
                 // This syntax isn't accepted by `branch.{branch}`. Strip it.
-                let branch = branch.strip_prefix("heads/").unwrap_or(&branch);
+                let branch = current_branch.stdout();
+                let branch = branch.trim();
+                let branch = branch.strip_prefix("heads/").unwrap_or(branch);
                 git.arg("-c").arg(format!("branch.{branch}.remote=origin"));
             }
             git.args(["submodule", "update", "--init", "--recursive", "--depth=1"]);
@@ -1400,26 +1408,23 @@ impl Config {
             git.arg(relative_path);
             git
         };
-        if !self.check_run(&mut update(true)) {
-            self.check_run(&mut update(false));
+        if !update(true).allow_failure().run(self) {
+            update(false).allow_failure().run(self);
         }
 
         // Save any local changes, but avoid running `git stash pop` if there are none (since it will exit with an error).
         // diff-index reports the modifications through the exit status
-        let has_local_modifications = !self.check_run(submodule_git().allow_failure().args([
-            "diff-index",
-            "--quiet",
-            "HEAD",
-        ]));
+        let has_local_modifications =
+            !submodule_git().allow_failure().args(["diff-index", "--quiet", "HEAD"]).run(self);
         if has_local_modifications {
-            self.check_run(submodule_git().args(["stash", "push"]));
+            submodule_git().allow_failure().args(["stash", "push"]).run(self);
         }
 
-        self.check_run(submodule_git().args(["reset", "-q", "--hard"]));
-        self.check_run(submodule_git().args(["clean", "-qdfx"]));
+        submodule_git().allow_failure().args(["reset", "-q", "--hard"]).run(self);
+        submodule_git().allow_failure().args(["clean", "-qdfx"]).run(self);
 
         if has_local_modifications {
-            self.check_run(submodule_git().args(["stash", "pop"]));
+            submodule_git().allow_failure().args(["stash", "pop"]).run(self);
         }
     }
 
@@ -1435,7 +1440,8 @@ impl Config {
             return;
         }
 
-        let stage0_output = output(Command::new(program_path).arg("--version"));
+        let stage0_output =
+            command(program_path).arg("--version").run_capture_stdout(self).stdout();
         let mut stage0_output = stage0_output.lines().next().unwrap().split(' ');
 
         let stage0_name = stage0_output.next().unwrap();
@@ -1472,7 +1478,7 @@ impl Config {
         debug_assertions_requested: bool,
         llvm_assertions: bool,
     ) -> Option<String> {
-        if !is_download_ci_available(&self.build.triple, llvm_assertions) {
+        if !is_download_ci_available(&self.host_target.triple, llvm_assertions) {
             return None;
         }
 
@@ -1708,7 +1714,7 @@ impl Config {
 
     /// Checks if the given target is the same as the host target.
     pub fn is_host_target(&self, target: TargetSelection) -> bool {
-        self.build == target
+        self.host_target == target
     }
 
     /// Returns `true` if this is an external version of LLVM not managed by bootstrap.
@@ -1741,4 +1747,18 @@ impl Config {
             _ => !self.is_system_llvm(target),
         }
     }
+
+    pub fn exec_ctx(&self) -> &ExecutionContext {
+        &self.exec_ctx
+    }
+
+    pub fn git_info(&self, omit_git_hash: bool, dir: &Path) -> GitInfo {
+        GitInfo::new(omit_git_hash, dir, self)
+    }
+}
+
+impl AsRef<ExecutionContext> for Config {
+    fn as_ref(&self) -> &ExecutionContext {
+        &self.exec_ctx
+    }
 }
diff --git a/src/bootstrap/src/core/config/flags.rs b/src/bootstrap/src/core/config/flags.rs
index 30617f58d43..ea0251e209a 100644
--- a/src/bootstrap/src/core/config/flags.rs
+++ b/src/bootstrap/src/core/config/flags.rs
@@ -59,7 +59,7 @@ pub struct Flags {
     pub build_dir: Option<PathBuf>,
 
     #[arg(global = true, long, value_hint = clap::ValueHint::Other, value_name = "BUILD")]
-    /// build target of the stage0 compiler
+    /// host target of the stage0 compiler
     pub build: Option<String>,
 
     #[arg(global = true, long, value_hint = clap::ValueHint::Other, value_name = "HOST", value_parser = target_selection_list)]
@@ -209,7 +209,8 @@ impl Flags {
             HelpVerboseOnly::try_parse_from(normalize_args(args))
         {
             println!("NOTE: updating submodules before printing available paths");
-            let config = Config::parse(Self::parse(&[String::from("build")]));
+            let flags = Self::parse(&[String::from("build")]);
+            let config = Config::parse(flags);
             let build = Build::new(config);
             let paths = Builder::get_help(&build, subcommand);
             if let Some(s) = paths {
diff --git a/src/bootstrap/src/core/config/toml/build.rs b/src/bootstrap/src/core/config/toml/build.rs
index 85ded3c87d9..98e1194de72 100644
--- a/src/bootstrap/src/core/config/toml/build.rs
+++ b/src/bootstrap/src/core/config/toml/build.rs
@@ -6,6 +6,8 @@
 //! various feature flags. These options apply across different stages and components
 //! unless specifically overridden by other configuration sections or command-line flags.
 
+use std::collections::HashMap;
+
 use serde::{Deserialize, Deserializer};
 
 use crate::core::config::toml::ReplaceOpt;
@@ -42,6 +44,7 @@ define_config! {
         bootstrap_cache_path: Option<PathBuf> = "bootstrap-cache-path",
         extended: Option<bool> = "extended",
         tools: Option<HashSet<String>> = "tools",
+        tool: Option<HashMap<String, Tool>> = "tool",
         verbose: Option<usize> = "verbose",
         sanitizers: Option<bool> = "sanitizers",
         profiler: Option<bool> = "profiler",
@@ -70,3 +73,11 @@ define_config! {
         exclude: Option<Vec<PathBuf>> = "exclude",
     }
 }
+
+define_config! {
+    /// Configuration specific for some tool, e.g. which features to enable during build.
+    #[derive(Default, Clone)]
+    struct Tool {
+        features: Option<Vec<String>> = "features",
+    }
+}
diff --git a/src/bootstrap/src/core/config/toml/mod.rs b/src/bootstrap/src/core/config/toml/mod.rs
index ac4e249e580..01eb243159c 100644
--- a/src/bootstrap/src/core/config/toml/mod.rs
+++ b/src/bootstrap/src/core/config/toml/mod.rs
@@ -147,7 +147,7 @@ impl Config {
         }
 
         let builder_config_path =
-            self.out.join(self.build.triple).join(build_name).join(BUILDER_CONFIG_FILENAME);
+            self.out.join(self.host_target.triple).join(build_name).join(BUILDER_CONFIG_FILENAME);
         Self::get_toml(&builder_config_path)
     }
 
diff --git a/src/bootstrap/src/core/config/toml/rust.rs b/src/bootstrap/src/core/config/toml/rust.rs
index 81f95f356a5..642f2f2271d 100644
--- a/src/bootstrap/src/core/config/toml/rust.rs
+++ b/src/bootstrap/src/core/config/toml/rust.rs
@@ -321,11 +321,11 @@ pub fn check_incompatible_options_for_ci_rustc(
         rpath,
         channel,
         description,
-        incremental,
         default_linker,
         std_features,
 
         // Rest of the options can simply be ignored.
+        incremental: _,
         debug: _,
         codegen_units: _,
         codegen_units_std: _,
@@ -389,7 +389,6 @@ pub fn check_incompatible_options_for_ci_rustc(
 
     warn!(current_rust_config.channel, channel, "rust");
     warn!(current_rust_config.description, description, "rust");
-    warn!(current_rust_config.incremental, incremental, "rust");
 
     Ok(())
 }
@@ -622,13 +621,13 @@ impl Config {
         //   thus, disabled
         // - similarly, lld will not be built nor used by default when explicitly asked not to, e.g.
         //   when the config sets `rust.lld = false`
-        if self.build.triple == "x86_64-unknown-linux-gnu"
-            && self.hosts == [self.build]
+        if self.host_target.triple == "x86_64-unknown-linux-gnu"
+            && self.hosts == [self.host_target]
             && (self.channel == "dev" || self.channel == "nightly")
         {
             let no_llvm_config = self
                 .target_config
-                .get(&self.build)
+                .get(&self.host_target)
                 .is_some_and(|target_config| target_config.llvm_config.is_none());
             let enable_lld = self.llvm_from_ci || no_llvm_config;
             // Prefer the config setting in case an explicit opt-out is needed.
diff --git a/src/bootstrap/src/core/config/toml/target.rs b/src/bootstrap/src/core/config/toml/target.rs
index 7f074d1b25e..b9f6780ca3f 100644
--- a/src/bootstrap/src/core/config/toml/target.rs
+++ b/src/bootstrap/src/core/config/toml/target.rs
@@ -84,7 +84,7 @@ pub struct Target {
 impl Target {
     pub fn from_triple(triple: &str) -> Self {
         let mut target: Self = Default::default();
-        if triple.contains("-none") || triple.contains("nvptx") || triple.contains("switch") {
+        if !build_helper::targets::target_supports_std(triple) {
             target.no_std = true;
         }
         if triple.contains("emscripten") {
@@ -101,7 +101,7 @@ impl Config {
                 let mut target = Target::from_triple(&triple);
 
                 if let Some(ref s) = cfg.llvm_config {
-                    if self.download_rustc_commit.is_some() && triple == *self.build.triple {
+                    if self.download_rustc_commit.is_some() && triple == *self.host_target.triple {
                         panic!(
                             "setting llvm_config for the host is incompatible with download-rustc"
                         );
diff --git a/src/bootstrap/src/core/download.rs b/src/bootstrap/src/core/download.rs
index ba00b405c61..d7c6d8dbcc3 100644
--- a/src/bootstrap/src/core/download.rs
+++ b/src/bootstrap/src/core/download.rs
@@ -3,27 +3,19 @@ use std::ffi::OsString;
 use std::fs::{self, File};
 use std::io::{BufRead, BufReader, BufWriter, ErrorKind, Write};
 use std::path::{Path, PathBuf};
-use std::process::{Command, Stdio};
 use std::sync::OnceLock;
 
 use xz2::bufread::XzDecoder;
 
 use crate::core::config::BUILDER_CONFIG_FILENAME;
 use crate::utils::build_stamp::BuildStamp;
-use crate::utils::exec::{BootstrapCommand, command};
-use crate::utils::helpers::{check_run, exe, hex_encode, move_file};
+use crate::utils::exec::command;
+use crate::utils::helpers::{exe, hex_encode, move_file};
 use crate::{Config, t};
 
 static SHOULD_FIX_BINS_AND_DYLIBS: OnceLock<bool> = OnceLock::new();
 
-/// `Config::try_run` wrapper for this module to avoid warnings on `try_run`, since we don't have access to a `builder` yet.
-fn try_run(config: &Config, cmd: &mut Command) -> Result<(), ()> {
-    #[expect(deprecated)]
-    config.try_run(cmd)
-}
-
-fn extract_curl_version(out: &[u8]) -> semver::Version {
-    let out = String::from_utf8_lossy(out);
+fn extract_curl_version(out: String) -> semver::Version {
     // The output should look like this: "curl <major>.<minor>.<patch> ..."
     out.lines()
         .next()
@@ -32,18 +24,21 @@ fn extract_curl_version(out: &[u8]) -> semver::Version {
         .unwrap_or(semver::Version::new(1, 0, 0))
 }
 
-fn curl_version() -> semver::Version {
-    let mut curl = Command::new("curl");
+fn curl_version(config: &Config) -> semver::Version {
+    let mut curl = command("curl");
     curl.arg("-V");
-    let Ok(out) = curl.output() else { return semver::Version::new(1, 0, 0) };
-    let out = out.stdout;
-    extract_curl_version(&out)
+    let curl = curl.run_capture_stdout(config);
+    if curl.is_failure() {
+        return semver::Version::new(1, 0, 0);
+    }
+    let output = curl.stdout();
+    extract_curl_version(output)
 }
 
 /// Generic helpers that are useful anywhere in bootstrap.
 impl Config {
     pub fn is_verbose(&self) -> bool {
-        self.verbose > 0
+        self.exec_ctx.is_verbose()
     }
 
     pub(crate) fn create<P: AsRef<Path>>(&self, path: P, s: &str) {
@@ -70,35 +65,18 @@ impl Config {
         tmp
     }
 
-    /// Runs a command, printing out nice contextual information if it fails.
-    /// Returns false if do not execute at all, otherwise returns its
-    /// `status.success()`.
-    pub(crate) fn check_run(&self, cmd: &mut BootstrapCommand) -> bool {
-        if self.dry_run() && !cmd.run_always {
-            return true;
-        }
-        self.verbose(|| println!("running: {cmd:?}"));
-        check_run(cmd, self.is_verbose())
-    }
-
     /// Whether or not `fix_bin_or_dylib` needs to be run; can only be true
     /// on NixOS
     fn should_fix_bins_and_dylibs(&self) -> bool {
         let val = *SHOULD_FIX_BINS_AND_DYLIBS.get_or_init(|| {
-            match Command::new("uname").arg("-s").stderr(Stdio::inherit()).output() {
-                Err(_) => return false,
-                Ok(output) if !output.status.success() => return false,
-                Ok(output) => {
-                    let mut os_name = output.stdout;
-                    if os_name.last() == Some(&b'\n') {
-                        os_name.pop();
-                    }
-                    if os_name != b"Linux" {
-                        return false;
-                    }
-                }
+            let uname = command("uname").allow_failure().arg("-s").run_capture_stdout(self);
+            if uname.is_failure() {
+                return false;
+            }
+            let output = uname.stdout();
+            if !output.starts_with("Linux") {
+                return false;
             }
-
             // If the user has asked binaries to be patched for Nix, then
             // don't check for NixOS or `/lib`.
             // NOTE: this intentionally comes after the Linux check:
@@ -173,23 +151,18 @@ impl Config {
                 ];
             }
             ";
-            nix_build_succeeded = try_run(
-                self,
-                Command::new("nix-build").args([
-                    Path::new("-E"),
-                    Path::new(NIX_EXPR),
-                    Path::new("-o"),
-                    &nix_deps_dir,
-                ]),
-            )
-            .is_ok();
+            nix_build_succeeded = command("nix-build")
+                .allow_failure()
+                .args([Path::new("-E"), Path::new(NIX_EXPR), Path::new("-o"), &nix_deps_dir])
+                .run_capture_stdout(self)
+                .is_success();
             nix_deps_dir
         });
         if !nix_build_succeeded {
             return;
         }
 
-        let mut patchelf = Command::new(nix_deps_dir.join("bin/patchelf"));
+        let mut patchelf = command(nix_deps_dir.join("bin/patchelf"));
         patchelf.args(&[
             OsString::from("--add-rpath"),
             OsString::from(t!(fs::canonicalize(nix_deps_dir)).join("lib")),
@@ -200,8 +173,8 @@ impl Config {
             let dynamic_linker = t!(fs::read_to_string(dynamic_linker_path));
             patchelf.args(["--set-interpreter", dynamic_linker.trim_end()]);
         }
-
-        let _ = try_run(self, patchelf.arg(fname));
+        patchelf.arg(fname);
+        let _ = patchelf.allow_failure().run_capture_stdout(self);
     }
 
     fn download_file(&self, url: &str, dest_path: &Path, help_on_error: &str) {
@@ -230,7 +203,7 @@ impl Config {
         // options should be kept in sync with
         // src/bootstrap/src/core/download.rs
         // for consistency
-        let mut curl = command("curl");
+        let mut curl = command("curl").allow_failure();
         curl.args([
             // follow redirect
             "--location",
@@ -267,15 +240,15 @@ impl Config {
             curl.arg("--progress-bar");
         }
         // --retry-all-errors was added in 7.71.0, don't use it if curl is old.
-        if curl_version() >= semver::Version::new(7, 71, 0) {
+        if curl_version(self) >= semver::Version::new(7, 71, 0) {
             curl.arg("--retry-all-errors");
         }
         curl.arg(url);
-        if !self.check_run(&mut curl) {
-            if self.build.contains("windows-msvc") {
+        if !curl.run(self) {
+            if self.host_target.contains("windows-msvc") {
                 eprintln!("Fallback to PowerShell");
                 for _ in 0..3 {
-                    if try_run(self, Command::new("PowerShell.exe").args([
+                    let powershell = command("PowerShell.exe").allow_failure().args([
                         "/nologo",
                         "-Command",
                         "[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12;",
@@ -283,9 +256,12 @@ impl Config {
                             "(New-Object System.Net.WebClient).DownloadFile('{}', '{}')",
                             url, tempfile.to_str().expect("invalid UTF-8 not supported with powershell downloads"),
                         ),
-                    ])).is_err() {
+                    ]).run_capture_stdout(self);
+
+                    if powershell.is_failure() {
                         return;
                     }
+
                     eprintln!("\nspurious failure, trying again");
                 }
             }
@@ -424,7 +400,7 @@ impl Config {
 
         let date = &self.stage0_metadata.compiler.date;
         let version = &self.stage0_metadata.compiler.version;
-        let host = self.build;
+        let host = self.host_target;
 
         let clippy_stamp =
             BuildStamp::new(&self.initial_sysroot).with_prefix("clippy").add_stamp(date);
@@ -462,7 +438,7 @@ impl Config {
         let VersionMetadata { date, version } = self.stage0_metadata.rustfmt.as_ref()?;
         let channel = format!("{version}-{date}");
 
-        let host = self.build;
+        let host = self.host_target;
         let bin_root = self.out.join(host).join("rustfmt");
         let rustfmt_path = bin_root.join("bin").join(exe("rustfmt", host));
         let rustfmt_stamp = BuildStamp::new(&bin_root).with_prefix("rustfmt").add_stamp(channel);
@@ -570,11 +546,11 @@ impl Config {
         extra_components: &[&str],
         download_component: fn(&Config, String, &str, &str),
     ) {
-        let host = self.build.triple;
+        let host = self.host_target.triple;
         let bin_root = self.out.join(host).join(sysroot);
         let rustc_stamp = BuildStamp::new(&bin_root).with_prefix("rustc").add_stamp(stamp_key);
 
-        if !bin_root.join("bin").join(exe("rustc", self.build)).exists()
+        if !bin_root.join("bin").join(exe("rustc", self.host_target)).exists()
             || !rustc_stamp.is_up_to_date()
         {
             if bin_root.exists() {
@@ -643,7 +619,7 @@ impl Config {
             t!(fs::create_dir_all(&cache_dir));
         }
 
-        let bin_root = self.out.join(self.build).join(destination);
+        let bin_root = self.out.join(self.host_target).join(destination);
         let tarball = cache_dir.join(&filename);
         let (base_url, url, should_verify) = match mode {
             DownloadSource::CI => {
@@ -772,7 +748,7 @@ download-rustc = false
             let now = std::time::SystemTime::now();
             let file_times = fs::FileTimes::new().set_accessed(now).set_modified(now);
 
-            let llvm_config = llvm_root.join("bin").join(exe("llvm-config", self.build));
+            let llvm_config = llvm_root.join("bin").join(exe("llvm-config", self.host_target));
             t!(crate::utils::helpers::set_file_times(llvm_config, file_times));
 
             if self.should_fix_bins_and_dylibs() {
@@ -827,7 +803,7 @@ download-rustc = false
             &self.stage0_metadata.config.artifacts_server
         };
         let version = self.artifact_version_part(llvm_sha);
-        let filename = format!("rust-dev-{}-{}.tar.xz", version, self.build.triple);
+        let filename = format!("rust-dev-{}-{}.tar.xz", version, self.host_target.triple);
         let tarball = rustc_cache.join(&filename);
         if !tarball.exists() {
             let help_on_error = "ERROR: failed to download llvm from ci
@@ -857,7 +833,7 @@ download-rustc = false
         }
         let base = &self.stage0_metadata.config.artifacts_server;
         let version = self.artifact_version_part(gcc_sha);
-        let filename = format!("gcc-{version}-{}.tar.xz", self.build.triple);
+        let filename = format!("gcc-{version}-{}.tar.xz", self.host_target.triple);
         let tarball = gcc_cache.join(&filename);
         if !tarball.exists() {
             let help_on_error = "ERROR: failed to download gcc from ci
diff --git a/src/bootstrap/src/core/sanity.rs b/src/bootstrap/src/core/sanity.rs
index 59ae303e21e..493f73b21fe 100644
--- a/src/bootstrap/src/core/sanity.rs
+++ b/src/bootstrap/src/core/sanity.rs
@@ -109,9 +109,9 @@ pub fn check(build: &mut Build) {
 
     // Ensure that a compatible version of libstdc++ is available on the system when using `llvm.download-ci-llvm`.
     #[cfg(not(test))]
-    if !build.config.dry_run() && !build.build.is_msvc() && build.config.llvm_from_ci {
+    if !build.config.dry_run() && !build.host_target.is_msvc() && build.config.llvm_from_ci {
         let builder = Builder::new(build);
-        let libcxx_version = builder.ensure(tool::LibcxxVersionTool { target: build.build });
+        let libcxx_version = builder.ensure(tool::LibcxxVersionTool { target: build.host_target });
 
         match libcxx_version {
             tool::LibcxxVersion::Gnu(version) => {
@@ -200,12 +200,14 @@ than building it.
         .map(|p| cmd_finder.must_have(p))
         .or_else(|| cmd_finder.maybe_have("reuse"));
 
-    let stage0_supported_target_list: HashSet<String> = crate::utils::helpers::output(
-        command(&build.config.initial_rustc).args(["--print", "target-list"]).as_command_mut(),
-    )
-    .lines()
-    .map(|s| s.to_string())
-    .collect();
+    let stage0_supported_target_list: HashSet<String> = command(&build.config.initial_rustc)
+        .args(["--print", "target-list"])
+        .run_always()
+        .run_capture_stdout(&build)
+        .stdout()
+        .lines()
+        .map(|s| s.to_string())
+        .collect();
 
     // Compiler tools like `cc` and `ar` are not configured for cross-targets on certain subcommands
     // because they are not needed.
@@ -237,7 +239,7 @@ than building it.
         }
 
         // skip check for cross-targets
-        if skip_target_sanity && target != &build.build {
+        if skip_target_sanity && target != &build.host_target {
             continue;
         }
 
@@ -308,7 +310,7 @@ than building it.
 
             if build.config.llvm_enabled(*host) {
                 // Externally configured LLVM requires FileCheck to exist
-                let filecheck = build.llvm_filecheck(build.build);
+                let filecheck = build.llvm_filecheck(build.host_target);
                 if !filecheck.starts_with(&build.out)
                     && !filecheck.exists()
                     && build.config.codegen_tests
@@ -333,7 +335,7 @@ than building it.
         }
 
         // skip check for cross-targets
-        if skip_target_sanity && target != &build.build {
+        if skip_target_sanity && target != &build.host_target {
             continue;
         }
 
@@ -364,7 +366,7 @@ than building it.
             // Cygwin. The Cygwin build does not have generators for Visual
             // Studio, so detect that here and error.
             let out =
-                command("cmake").arg("--help").run_always().run_capture_stdout(build).stdout();
+                command("cmake").arg("--help").run_always().run_capture_stdout(&build).stdout();
             if !out.contains("Visual Studio") {
                 panic!(
                     "
diff --git a/src/bootstrap/src/lib.rs b/src/bootstrap/src/lib.rs
index 7db57889009..f1628f34dda 100644
--- a/src/bootstrap/src/lib.rs
+++ b/src/bootstrap/src/lib.rs
@@ -17,11 +17,10 @@
 //! also check out the `src/bootstrap/README.md` file for more information.
 #![cfg_attr(test, allow(unused))]
 
-use std::cell::{Cell, RefCell};
+use std::cell::Cell;
 use std::collections::{BTreeSet, HashMap, HashSet};
 use std::fmt::Display;
 use std::path::{Path, PathBuf};
-use std::process::Command;
 use std::sync::OnceLock;
 use std::time::SystemTime;
 use std::{env, fs, io, str};
@@ -32,13 +31,14 @@ use cc::Tool;
 use termcolor::{ColorChoice, StandardStream, WriteColor};
 use utils::build_stamp::BuildStamp;
 use utils::channel::GitInfo;
+use utils::execution_context::ExecutionContext;
 
 use crate::core::builder;
 use crate::core::builder::Kind;
 use crate::core::config::{DryRun, LldMode, LlvmLibunwind, TargetSelection, flags};
 use crate::utils::exec::{BehaviorOnFailure, BootstrapCommand, CommandOutput, OutputMode, command};
 use crate::utils::helpers::{
-    self, dir_is_empty, exe, libdir, output, set_file_times, split_debuginfo, symlink_dir,
+    self, dir_is_empty, exe, libdir, set_file_times, split_debuginfo, symlink_dir,
 };
 
 mod core;
@@ -174,7 +174,7 @@ pub struct Build {
     verbosity: usize,
 
     /// Build triple for the pre-compiled snapshot compiler.
-    build: TargetSelection,
+    host_target: TargetSelection,
     /// Which triples to produce a compiler toolchain for.
     hosts: Vec<TargetSelection>,
     /// Which triples to build libraries (core/alloc/std/test/proc_macro) for.
@@ -189,16 +189,17 @@ pub struct Build {
 
     // Runtime state filled in later on
     // C/C++ compilers and archiver for all targets
-    cc: RefCell<HashMap<TargetSelection, cc::Tool>>,
-    cxx: RefCell<HashMap<TargetSelection, cc::Tool>>,
-    ar: RefCell<HashMap<TargetSelection, PathBuf>>,
-    ranlib: RefCell<HashMap<TargetSelection, PathBuf>>,
+    cc: HashMap<TargetSelection, cc::Tool>,
+    cxx: HashMap<TargetSelection, cc::Tool>,
+    ar: HashMap<TargetSelection, PathBuf>,
+    ranlib: HashMap<TargetSelection, PathBuf>,
+    wasi_sdk_path: Option<PathBuf>,
+
     // Miscellaneous
     // allow bidirectional lookups: both name -> path and path -> name
     crates: HashMap<String, Crate>,
     crate_paths: HashMap<PathBuf, String>,
     is_sudo: bool,
-    delayed_failures: RefCell<Vec<String>>,
     prerelease_version: Cell<Option<u32>>,
 
     #[cfg(feature = "build-metrics")]
@@ -376,10 +377,13 @@ impl Build {
         let in_tree_llvm_info = config.in_tree_llvm_info.clone();
         let in_tree_gcc_info = config.in_tree_gcc_info.clone();
 
-        let initial_target_libdir =
-            output(Command::new(&config.initial_rustc).args(["--print", "target-libdir"]))
-                .trim()
-                .to_owned();
+        let initial_target_libdir = command(&config.initial_rustc)
+            .run_always()
+            .args(["--print", "target-libdir"])
+            .run_capture_stdout(&config)
+            .stdout()
+            .trim()
+            .to_owned();
 
         let initial_target_dir = Path::new(&initial_target_libdir)
             .parent()
@@ -420,7 +424,7 @@ impl Build {
         if bootstrap_out.ends_with("deps") {
             bootstrap_out.pop();
         }
-        if !bootstrap_out.join(exe("rustc", config.build)).exists() && !cfg!(test) {
+        if !bootstrap_out.join(exe("rustc", config.host_target)).exists() && !cfg!(test) {
             // this restriction can be lifted whenever https://github.com/rust-lang/rfcs/pull/3028 is implemented
             panic!(
                 "`rustc` not found in {}, run `cargo build --bins` before `cargo run`",
@@ -436,7 +440,9 @@ impl Build {
             initial_lld,
             initial_relative_libdir,
             initial_rustc: config.initial_rustc.clone(),
-            initial_rustdoc: config.initial_rustc.with_file_name(exe("rustdoc", config.build)),
+            initial_rustdoc: config
+                .initial_rustc
+                .with_file_name(exe("rustdoc", config.host_target)),
             initial_cargo: config.initial_cargo.clone(),
             initial_sysroot: config.initial_sysroot.clone(),
             local_rebuild: config.local_rebuild,
@@ -444,7 +450,7 @@ impl Build {
             doc_tests: config.cmd.doc_tests(),
             verbosity: config.verbose,
 
-            build: config.build,
+            host_target: config.host_target,
             hosts: config.hosts.clone(),
             targets: config.targets.clone(),
 
@@ -462,14 +468,14 @@ impl Build {
             enzyme_info,
             in_tree_llvm_info,
             in_tree_gcc_info,
-            cc: RefCell::new(HashMap::new()),
-            cxx: RefCell::new(HashMap::new()),
-            ar: RefCell::new(HashMap::new()),
-            ranlib: RefCell::new(HashMap::new()),
+            cc: HashMap::new(),
+            cxx: HashMap::new(),
+            ar: HashMap::new(),
+            ranlib: HashMap::new(),
+            wasi_sdk_path: env::var_os("WASI_SDK_PATH").map(PathBuf::from),
             crates: HashMap::new(),
             crate_paths: HashMap::new(),
             is_sudo,
-            delayed_failures: RefCell::new(Vec::new()),
             prerelease_version: Cell::new(None),
 
             #[cfg(feature = "build-metrics")]
@@ -478,8 +484,11 @@ impl Build {
 
         // If local-rust is the same major.minor as the current version, then force a
         // local-rebuild
-        let local_version_verbose =
-            output(Command::new(&build.initial_rustc).arg("--version").arg("--verbose"));
+        let local_version_verbose = command(&build.initial_rustc)
+            .run_always()
+            .args(["--version", "--verbose"])
+            .run_capture_stdout(&build)
+            .stdout();
         let local_release = local_version_verbose
             .lines()
             .filter_map(|x| x.strip_prefix("release:"))
@@ -492,7 +501,7 @@ impl Build {
         }
 
         build.verbose(|| println!("finding compilers"));
-        utils::cc_detect::find(&build);
+        utils::cc_detect::fill_compilers(&mut build);
         // When running `setup`, the profile is about to change, so any requirements we have now may
         // be different on the next invocation. Don't check for them until the next time x.py is
         // run. This is ok because `setup` never runs any build commands, so it won't fail if commands are missing.
@@ -522,7 +531,7 @@ impl Build {
         }
 
         // Create symbolic link to use host sysroot from a consistent path (e.g., in the rust-analyzer config file).
-        let build_triple = build.out.join(build.build);
+        let build_triple = build.out.join(build.host_target);
         t!(fs::create_dir_all(&build_triple));
         let host = build.out.join("host");
         if host.is_symlink() {
@@ -587,14 +596,6 @@ impl Build {
         }
     }
 
-    /// Updates all submodules, and exits with an error if submodule
-    /// management is disabled and the submodule does not exist.
-    pub fn require_and_update_all_submodules(&self) {
-        for submodule in build_helper::util::parse_gitmodules(&self.src) {
-            self.require_submodule(submodule, None);
-        }
-    }
-
     /// If any submodule has been initialized already, sync it unconditionally.
     /// This avoids contributors checking in a submodule change by accident.
     fn update_existing_submodules(&self) {
@@ -629,7 +630,7 @@ impl Build {
             return;
         }
 
-        if GitInfo::new(false, Path::new(submodule)).is_managed_git_subrepository() {
+        if config.git_info(false, Path::new(submodule)).is_managed_git_subrepository() {
             config.update_submodule(submodule);
         }
     }
@@ -684,7 +685,7 @@ impl Build {
                 #[cfg(feature = "tracing")]
                 let _sanity_check_span =
                     span!(tracing::Level::DEBUG, "(1) executing dry-run sanity-check").entered();
-                self.config.dry_run = DryRun::SelfCheck;
+                self.config.set_dry_run(DryRun::SelfCheck);
                 let builder = builder::Builder::new(self);
                 builder.execute_cli();
             }
@@ -694,7 +695,7 @@ impl Build {
                 #[cfg(feature = "tracing")]
                 let _actual_run_span =
                     span!(tracing::Level::DEBUG, "(2) executing actual run").entered();
-                self.config.dry_run = DryRun::Disabled;
+                self.config.set_dry_run(DryRun::Disabled);
                 let builder = builder::Builder::new(self);
                 builder.execute_cli();
             }
@@ -710,14 +711,7 @@ impl Build {
         debug!("checking for postponed test failures from `test  --no-fail-fast`");
 
         // Check for postponed failures from `test --no-fail-fast`.
-        let failures = self.delayed_failures.borrow();
-        if !failures.is_empty() {
-            eprintln!("\n{} command(s) did not execute successfully:\n", failures.len());
-            for failure in failures.iter() {
-                eprintln!("  - {failure}\n");
-            }
-            exit!(1);
-        }
+        self.config.exec_ctx().report_failures_and_exit();
 
         #[cfg(feature = "build-metrics")]
         self.metrics.persist(self);
@@ -940,146 +934,24 @@ impl Build {
 
     /// Returns the libdir of the snapshot compiler.
     fn rustc_snapshot_libdir(&self) -> PathBuf {
-        self.rustc_snapshot_sysroot().join(libdir(self.config.build))
+        self.rustc_snapshot_sysroot().join(libdir(self.config.host_target))
     }
 
     /// Returns the sysroot of the snapshot compiler.
     fn rustc_snapshot_sysroot(&self) -> &Path {
         static SYSROOT_CACHE: OnceLock<PathBuf> = OnceLock::new();
         SYSROOT_CACHE.get_or_init(|| {
-            let mut rustc = Command::new(&self.initial_rustc);
-            rustc.args(["--print", "sysroot"]);
-            output(&mut rustc).trim().into()
+            command(&self.initial_rustc)
+                .run_always()
+                .args(["--print", "sysroot"])
+                .run_capture_stdout(self)
+                .stdout()
+                .trim()
+                .to_owned()
+                .into()
         })
     }
 
-    /// Execute a command and return its output.
-    /// Note: Ideally, you should use one of the BootstrapCommand::run* functions to
-    /// execute commands. They internally call this method.
-    #[track_caller]
-    fn run(
-        &self,
-        command: &mut BootstrapCommand,
-        stdout: OutputMode,
-        stderr: OutputMode,
-    ) -> CommandOutput {
-        command.mark_as_executed();
-        if self.config.dry_run() && !command.run_always {
-            return CommandOutput::default();
-        }
-
-        #[cfg(feature = "tracing")]
-        let _run_span = trace_cmd!(command);
-
-        let created_at = command.get_created_location();
-        let executed_at = std::panic::Location::caller();
-
-        self.verbose(|| {
-            println!("running: {command:?} (created at {created_at}, executed at {executed_at})")
-        });
-
-        let cmd = command.as_command_mut();
-        cmd.stdout(stdout.stdio());
-        cmd.stderr(stderr.stdio());
-
-        let output = cmd.output();
-
-        use std::fmt::Write;
-
-        let mut message = String::new();
-        let output: CommandOutput = match output {
-            // Command has succeeded
-            Ok(output) if output.status.success() => {
-                CommandOutput::from_output(output, stdout, stderr)
-            }
-            // Command has started, but then it failed
-            Ok(output) => {
-                writeln!(
-                    message,
-                    r#"
-Command {command:?} did not execute successfully.
-Expected success, got {}
-Created at: {created_at}
-Executed at: {executed_at}"#,
-                    output.status,
-                )
-                .unwrap();
-
-                let output: CommandOutput = CommandOutput::from_output(output, stdout, stderr);
-
-                // If the output mode is OutputMode::Capture, we can now print the output.
-                // If it is OutputMode::Print, then the output has already been printed to
-                // stdout/stderr, and we thus don't have anything captured to print anyway.
-                if stdout.captures() {
-                    writeln!(message, "\nSTDOUT ----\n{}", output.stdout().trim()).unwrap();
-                }
-                if stderr.captures() {
-                    writeln!(message, "\nSTDERR ----\n{}", output.stderr().trim()).unwrap();
-                }
-                output
-            }
-            // The command did not even start
-            Err(e) => {
-                writeln!(
-                    message,
-                    "\n\nCommand {command:?} did not execute successfully.\
-            \nIt was not possible to execute the command: {e:?}"
-                )
-                .unwrap();
-                CommandOutput::did_not_start(stdout, stderr)
-            }
-        };
-
-        let fail = |message: &str, output: CommandOutput| -> ! {
-            if self.is_verbose() {
-                println!("{message}");
-            } else {
-                let (stdout, stderr) = (output.stdout_if_present(), output.stderr_if_present());
-                // If the command captures output, the user would not see any indication that
-                // it has failed. In this case, print a more verbose error, since to provide more
-                // context.
-                if stdout.is_some() || stderr.is_some() {
-                    if let Some(stdout) =
-                        output.stdout_if_present().take_if(|s| !s.trim().is_empty())
-                    {
-                        println!("STDOUT:\n{stdout}\n");
-                    }
-                    if let Some(stderr) =
-                        output.stderr_if_present().take_if(|s| !s.trim().is_empty())
-                    {
-                        println!("STDERR:\n{stderr}\n");
-                    }
-                    println!("Command {command:?} has failed. Rerun with -v to see more details.");
-                } else {
-                    println!("Command has failed. Rerun with -v to see more details.");
-                }
-            }
-            exit!(1);
-        };
-
-        if !output.is_success() {
-            match command.failure_behavior {
-                BehaviorOnFailure::DelayFail => {
-                    if self.fail_fast {
-                        fail(&message, output);
-                    }
-
-                    let mut failures = self.delayed_failures.borrow_mut();
-                    failures.push(message);
-                }
-                BehaviorOnFailure::Exit => {
-                    fail(&message, output);
-                }
-                BehaviorOnFailure::Ignore => {
-                    // If failures are allowed, either the error has been printed already
-                    // (OutputMode::Print) or the user used a capture output mode and wants to
-                    // handle the error output on their own.
-                }
-            }
-        }
-        output
-    }
-
     /// Check if verbosity is greater than the `level`
     pub fn is_verbose_than(&self, level: usize) -> bool {
         self.verbosity > level
@@ -1093,7 +965,7 @@ Executed at: {executed_at}"#,
     }
 
     fn info(&self, msg: &str) {
-        match self.config.dry_run {
+        match self.config.get_dry_run() {
             DryRun::SelfCheck => (),
             DryRun::Disabled | DryRun::UserSelected => {
                 println!("{msg}");
@@ -1108,7 +980,7 @@ Executed at: {executed_at}"#,
         what: impl Display,
         target: impl Into<Option<TargetSelection>>,
     ) -> Option<gha::Group> {
-        self.msg(Kind::Clippy, self.config.stage, what, self.config.build, target)
+        self.msg(Kind::Clippy, self.config.stage, what, self.config.host_target, target)
     }
 
     #[must_use = "Groups should not be dropped until the Step finishes running"]
@@ -1123,7 +995,7 @@ Executed at: {executed_at}"#,
             Kind::Check,
             custom_stage.unwrap_or(self.config.stage),
             what,
-            self.config.build,
+            self.config.host_target,
             target,
         )
     }
@@ -1216,7 +1088,7 @@ Executed at: {executed_at}"#,
 
     #[track_caller]
     fn group(&self, msg: &str) -> Option<gha::Group> {
-        match self.config.dry_run {
+        match self.config.get_dry_run() {
             DryRun::SelfCheck => None,
             DryRun::Disabled | DryRun::UserSelected => Some(gha::group(msg)),
         }
@@ -1266,17 +1138,17 @@ Executed at: {executed_at}"#,
         if self.config.dry_run() {
             return PathBuf::new();
         }
-        self.cc.borrow()[&target].path().into()
+        self.cc[&target].path().into()
     }
 
     /// Returns the internal `cc::Tool` for the C compiler.
     fn cc_tool(&self, target: TargetSelection) -> Tool {
-        self.cc.borrow()[&target].clone()
+        self.cc[&target].clone()
     }
 
     /// Returns the internal `cc::Tool` for the C++ compiler.
     fn cxx_tool(&self, target: TargetSelection) -> Tool {
-        self.cxx.borrow()[&target].clone()
+        self.cxx[&target].clone()
     }
 
     /// Returns C flags that `cc-rs` thinks should be enabled for the
@@ -1286,8 +1158,8 @@ Executed at: {executed_at}"#,
             return Vec::new();
         }
         let base = match c {
-            CLang::C => self.cc.borrow()[&target].clone(),
-            CLang::Cxx => self.cxx.borrow()[&target].clone(),
+            CLang::C => self.cc[&target].clone(),
+            CLang::Cxx => self.cxx[&target].clone(),
         };
 
         // Filter out -O and /O (the optimization flags) that we picked up
@@ -1340,7 +1212,7 @@ Executed at: {executed_at}"#,
         if self.config.dry_run() {
             return None;
         }
-        self.ar.borrow().get(&target).cloned()
+        self.ar.get(&target).cloned()
     }
 
     /// Returns the path to the `ranlib` utility for the target specified.
@@ -1348,7 +1220,7 @@ Executed at: {executed_at}"#,
         if self.config.dry_run() {
             return None;
         }
-        self.ranlib.borrow().get(&target).cloned()
+        self.ranlib.get(&target).cloned()
     }
 
     /// Returns the path to the C++ compiler for the target specified.
@@ -1356,7 +1228,7 @@ Executed at: {executed_at}"#,
         if self.config.dry_run() {
             return Ok(PathBuf::new());
         }
-        match self.cxx.borrow().get(&target) {
+        match self.cxx.get(&target) {
             Some(p) => Ok(p.path().into()),
             None => Err(format!("target `{target}` is not configured as a host, only as a target")),
         }
@@ -1373,7 +1245,7 @@ Executed at: {executed_at}"#,
         } else if target.contains("vxworks") {
             // need to use CXX compiler as linker to resolve the exception functions
             // that are only existed in CXX libraries
-            Some(self.cxx.borrow()[&target].path().into())
+            Some(self.cxx[&target].path().into())
         } else if !self.config.is_host_target(target)
             && helpers::use_host_linker(target)
             && !target.is_msvc()
@@ -1381,7 +1253,7 @@ Executed at: {executed_at}"#,
             Some(self.cc(target))
         } else if self.config.lld_mode.is_used()
             && self.is_lld_direct_linker(target)
-            && self.build == target
+            && self.host_target == target
         {
             match self.config.lld_mode {
                 LldMode::SelfContained => Some(self.initial_lld.clone()),
@@ -1535,7 +1407,7 @@ Executed at: {executed_at}"#,
 
     /// Path to the python interpreter to use
     fn python(&self) -> &Path {
-        if self.config.build.ends_with("apple-darwin") {
+        if self.config.host_target.ends_with("apple-darwin") {
             // Force /usr/bin/python3 on macOS for LLDB tests because we're loading the
             // LLDB plugin's compiled module which only works with the system python
             // (namely not Homebrew-installed python)
@@ -1575,7 +1447,7 @@ Executed at: {executed_at}"#,
         !self.config.full_bootstrap
             && !self.config.download_rustc()
             && stage >= 2
-            && (self.hosts.contains(&target) || target == self.build)
+            && (self.hosts.contains(&target) || target == self.host_target)
     }
 
     /// Checks whether the `compiler` compiling for `target` should be forced to
@@ -2012,7 +1884,7 @@ to download LLVM rather than building it.
         // In these cases we automatically enable Ninja if we find it in the
         // environment.
         if !self.config.ninja_in_file
-            && self.config.build.is_msvc()
+            && self.config.host_target.is_msvc()
             && cmd_finder.maybe_have("ninja").is_some()
         {
             return true;
@@ -2045,6 +1917,16 @@ to download LLVM rather than building it.
         stream.reset().unwrap();
         result
     }
+
+    pub fn exec_ctx(&self) -> &ExecutionContext {
+        &self.config.exec_ctx
+    }
+}
+
+impl AsRef<ExecutionContext> for Build {
+    fn as_ref(&self) -> &ExecutionContext {
+        &self.config.exec_ctx
+    }
 }
 
 #[cfg(unix)]
@@ -2071,7 +1953,7 @@ impl Compiler {
 
     /// Returns `true` if this is a snapshot compiler for `build`'s configuration
     pub fn is_snapshot(&self, build: &Build) -> bool {
-        self.stage == 0 && self.host == build.build
+        self.stage == 0 && self.host == build.host_target
     }
 
     /// Indicates whether the compiler was forced to use a specific stage.
diff --git a/src/bootstrap/src/utils/build_stamp/tests.rs b/src/bootstrap/src/utils/build_stamp/tests.rs
index 2d7d1f71246..f150266159a 100644
--- a/src/bootstrap/src/utils/build_stamp/tests.rs
+++ b/src/bootstrap/src/utils/build_stamp/tests.rs
@@ -1,32 +1,28 @@
 use std::path::PathBuf;
 
-use crate::{BuildStamp, Config, Flags};
+use tempfile::TempDir;
 
-fn temp_dir() -> PathBuf {
-    let config =
-        Config::parse(Flags::parse(&["check".to_owned(), "--config=/does/not/exist".to_owned()]));
-    config.tempdir()
-}
+use crate::{BuildStamp, Config, Flags};
 
 #[test]
 #[should_panic(expected = "prefix can not start or end with '.'")]
 fn test_with_invalid_prefix() {
-    let dir = temp_dir();
-    BuildStamp::new(&dir).with_prefix(".invalid");
+    let dir = TempDir::new().unwrap();
+    BuildStamp::new(dir.path()).with_prefix(".invalid");
 }
 
 #[test]
 #[should_panic(expected = "prefix can not start or end with '.'")]
 fn test_with_invalid_prefix2() {
-    let dir = temp_dir();
-    BuildStamp::new(&dir).with_prefix("invalid.");
+    let dir = TempDir::new().unwrap();
+    BuildStamp::new(dir.path()).with_prefix("invalid.");
 }
 
 #[test]
 fn test_is_up_to_date() {
-    let dir = temp_dir();
+    let dir = TempDir::new().unwrap();
 
-    let mut build_stamp = BuildStamp::new(&dir).add_stamp("v1.0.0");
+    let mut build_stamp = BuildStamp::new(dir.path()).add_stamp("v1.0.0");
     build_stamp.write().unwrap();
 
     assert!(
@@ -45,9 +41,9 @@ fn test_is_up_to_date() {
 
 #[test]
 fn test_with_prefix() {
-    let dir = temp_dir();
+    let dir = TempDir::new().unwrap();
 
-    let stamp = BuildStamp::new(&dir).add_stamp("v1.0.0");
+    let stamp = BuildStamp::new(dir.path()).add_stamp("v1.0.0");
     assert_eq!(stamp.path.file_name().unwrap(), ".stamp");
 
     let stamp = stamp.with_prefix("test");
diff --git a/src/bootstrap/src/utils/cache.rs b/src/bootstrap/src/utils/cache.rs
index 46eeffad88c..0c737470958 100644
--- a/src/bootstrap/src/utils/cache.rs
+++ b/src/bootstrap/src/utils/cache.rs
@@ -17,6 +17,7 @@ use std::borrow::Borrow;
 use std::cell::RefCell;
 use std::cmp::Ordering;
 use std::collections::HashMap;
+use std::fmt::Debug;
 use std::hash::{Hash, Hasher};
 use std::marker::PhantomData;
 use std::ops::Deref;
@@ -208,25 +209,30 @@ pub static INTERNER: LazyLock<Interner> = LazyLock::new(Interner::default);
 /// any type in its output. It is a write-once cache; values are never evicted,
 /// which means that references to the value can safely be returned from the
 /// `get()` method.
-#[derive(Debug)]
-pub struct Cache(
-    RefCell<
+#[derive(Debug, Default)]
+pub struct Cache {
+    cache: RefCell<
         HashMap<
             TypeId,
             Box<dyn Any>, // actually a HashMap<Step, Interned<Step::Output>>
         >,
     >,
-);
+    #[cfg(test)]
+    /// Contains steps in the same order in which they were executed
+    /// Useful for tests
+    /// Tuples (step, step output)
+    executed_steps: RefCell<Vec<(Box<dyn Any>, Box<dyn Any>)>>,
+}
 
 impl Cache {
     /// Creates a new empty cache.
     pub fn new() -> Cache {
-        Cache(RefCell::new(HashMap::new()))
+        Cache::default()
     }
 
     /// Stores the result of a computation step in the cache.
     pub fn put<S: Step>(&self, step: S, value: S::Output) {
-        let mut cache = self.0.borrow_mut();
+        let mut cache = self.cache.borrow_mut();
         let type_id = TypeId::of::<S>();
         let stepcache = cache
             .entry(type_id)
@@ -234,12 +240,20 @@ impl Cache {
             .downcast_mut::<HashMap<S, S::Output>>()
             .expect("invalid type mapped");
         assert!(!stepcache.contains_key(&step), "processing {step:?} a second time");
+
+        #[cfg(test)]
+        {
+            let step: Box<dyn Any> = Box::new(step.clone());
+            let output: Box<dyn Any> = Box::new(value.clone());
+            self.executed_steps.borrow_mut().push((step, output));
+        }
+
         stepcache.insert(step, value);
     }
 
     /// Retrieves a cached result for the given step, if available.
     pub fn get<S: Step>(&self, step: &S) -> Option<S::Output> {
-        let mut cache = self.0.borrow_mut();
+        let mut cache = self.cache.borrow_mut();
         let type_id = TypeId::of::<S>();
         let stepcache = cache
             .entry(type_id)
@@ -252,8 +266,8 @@ impl Cache {
 
 #[cfg(test)]
 impl Cache {
-    pub fn all<S: Ord + Clone + Step>(&mut self) -> Vec<(S, S::Output)> {
-        let cache = self.0.get_mut();
+    pub fn all<S: Ord + Step>(&mut self) -> Vec<(S, S::Output)> {
+        let cache = self.cache.get_mut();
         let type_id = TypeId::of::<S>();
         let mut v = cache
             .remove(&type_id)
@@ -265,7 +279,12 @@ impl Cache {
     }
 
     pub fn contains<S: Step>(&self) -> bool {
-        self.0.borrow().contains_key(&TypeId::of::<S>())
+        self.cache.borrow().contains_key(&TypeId::of::<S>())
+    }
+
+    #[cfg(test)]
+    pub fn into_executed_steps(mut self) -> Vec<(Box<dyn Any>, Box<dyn Any>)> {
+        mem::take(&mut self.executed_steps.borrow_mut())
     }
 }
 
diff --git a/src/bootstrap/src/utils/cc_detect.rs b/src/bootstrap/src/utils/cc_detect.rs
index 5c9e30706ee..dcafeb80f90 100644
--- a/src/bootstrap/src/utils/cc_detect.rs
+++ b/src/bootstrap/src/utils/cc_detect.rs
@@ -39,7 +39,7 @@ fn new_cc_build(build: &Build, target: TargetSelection) -> cc::Build {
         // Compress debuginfo
         .flag_if_supported("-gz")
         .target(&target.triple)
-        .host(&build.build.triple);
+        .host(&build.host_target.triple);
     match build.crt_static(target) {
         Some(a) => {
             cfg.static_crt(a);
@@ -61,8 +61,8 @@ fn new_cc_build(build: &Build, target: TargetSelection) -> cc::Build {
 ///
 /// This function determines which targets need a C compiler (and, if needed, a C++ compiler)
 /// by combining the primary build target, host targets, and any additional targets. For
-/// each target, it calls [`find_target`] to configure the necessary compiler tools.
-pub fn find(build: &Build) {
+/// each target, it calls [`fill_target_compiler`] to configure the necessary compiler tools.
+pub fn fill_compilers(build: &mut Build) {
     let targets: HashSet<_> = match build.config.cmd {
         // We don't need to check cross targets for these commands.
         crate::Subcommand::Clean { .. }
@@ -70,7 +70,7 @@ pub fn find(build: &Build) {
         | crate::Subcommand::Suggest { .. }
         | crate::Subcommand::Format { .. }
         | crate::Subcommand::Setup { .. } => {
-            build.hosts.iter().cloned().chain(iter::once(build.build)).collect()
+            build.hosts.iter().cloned().chain(iter::once(build.host_target)).collect()
         }
 
         _ => {
@@ -81,13 +81,13 @@ pub fn find(build: &Build) {
                 .iter()
                 .chain(&build.hosts)
                 .cloned()
-                .chain(iter::once(build.build))
+                .chain(iter::once(build.host_target))
                 .collect()
         }
     };
 
     for target in targets.into_iter() {
-        find_target(build, target);
+        fill_target_compiler(build, target);
     }
 }
 
@@ -96,7 +96,7 @@ pub fn find(build: &Build) {
 /// This function uses both user-specified configuration (from `bootstrap.toml`) and auto-detection
 /// logic to determine the correct C/C++ compilers for the target. It also determines the appropriate
 /// archiver (`ar`) and sets up additional compilation flags (both handled and unhandled).
-pub fn find_target(build: &Build, target: TargetSelection) {
+pub fn fill_target_compiler(build: &mut Build, target: TargetSelection) {
     let mut cfg = new_cc_build(build, target);
     let config = build.config.target_config.get(&target);
     if let Some(cc) = config
@@ -113,7 +113,7 @@ pub fn find_target(build: &Build, target: TargetSelection) {
         cfg.try_get_archiver().map(|c| PathBuf::from(c.get_program())).ok()
     };
 
-    build.cc.borrow_mut().insert(target, compiler.clone());
+    build.cc.insert(target, compiler.clone());
     let mut cflags = build.cc_handled_clags(target, CLang::C);
     cflags.extend(build.cc_unhandled_cflags(target, GitRepo::Rustc, CLang::C));
 
@@ -135,7 +135,7 @@ pub fn find_target(build: &Build, target: TargetSelection) {
     // for VxWorks, record CXX compiler which will be used in lib.rs:linker()
     if cxx_configured || target.contains("vxworks") {
         let compiler = cfg.get_compiler();
-        build.cxx.borrow_mut().insert(target, compiler);
+        build.cxx.insert(target, compiler);
     }
 
     build.verbose(|| println!("CC_{} = {:?}", target.triple, build.cc(target)));
@@ -148,11 +148,11 @@ pub fn find_target(build: &Build, target: TargetSelection) {
     }
     if let Some(ar) = ar {
         build.verbose(|| println!("AR_{} = {ar:?}", target.triple));
-        build.ar.borrow_mut().insert(target, ar);
+        build.ar.insert(target, ar);
     }
 
     if let Some(ranlib) = config.and_then(|c| c.ranlib.clone()) {
-        build.ranlib.borrow_mut().insert(target, ranlib);
+        build.ranlib.insert(target, ranlib);
     }
 }
 
@@ -221,7 +221,10 @@ fn default_compiler(
         }
 
         t if t.contains("-wasi") => {
-            let root = PathBuf::from(std::env::var_os("WASI_SDK_PATH")?);
+            let root = build
+                .wasi_sdk_path
+                .as_ref()
+                .expect("WASI_SDK_PATH mut be configured for a -wasi target");
             let compiler = match compiler {
                 Language::C => format!("{t}-clang"),
                 Language::CPlusPlus => format!("{t}-clang++"),
diff --git a/src/bootstrap/src/utils/cc_detect/tests.rs b/src/bootstrap/src/utils/cc_detect/tests.rs
index 225fb7619b5..bed03c18aaa 100644
--- a/src/bootstrap/src/utils/cc_detect/tests.rs
+++ b/src/bootstrap/src/utils/cc_detect/tests.rs
@@ -77,11 +77,11 @@ fn test_new_cc_build() {
 
 #[test]
 fn test_default_compiler_wasi() {
-    let build = Build::new(Config { ..Config::parse(Flags::parse(&["build".to_owned()])) });
+    let mut build = Build::new(Config { ..Config::parse(Flags::parse(&["build".to_owned()])) });
     let target = TargetSelection::from_user("wasm32-wasi");
     let wasi_sdk = PathBuf::from("/wasi-sdk");
-    // SAFETY: bootstrap tests run on a single thread
-    unsafe { env::set_var("WASI_SDK_PATH", &wasi_sdk) };
+    build.wasi_sdk_path = Some(wasi_sdk.clone());
+
     let mut cfg = cc::Build::new();
     if let Some(result) = default_compiler(&mut cfg, Language::C, target.clone(), &build) {
         let expected = {
@@ -94,10 +94,6 @@ fn test_default_compiler_wasi() {
             "default_compiler should return a compiler path for wasi target when WASI_SDK_PATH is set"
         );
     }
-    // SAFETY: bootstrap tests run on a single thread
-    unsafe {
-        env::remove_var("WASI_SDK_PATH");
-    }
 }
 
 #[test]
@@ -119,18 +115,14 @@ fn test_find_target_with_config() {
     target_config.ar = Some(PathBuf::from("dummy-ar"));
     target_config.ranlib = Some(PathBuf::from("dummy-ranlib"));
     build.config.target_config.insert(target.clone(), target_config);
-    find_target(&build, target.clone());
-    let binding = build.cc.borrow();
-    let cc_tool = binding.get(&target).unwrap();
+    fill_target_compiler(&mut build, target.clone());
+    let cc_tool = build.cc.get(&target).unwrap();
     assert_eq!(cc_tool.path(), &PathBuf::from("dummy-cc"));
-    let binding = build.cxx.borrow();
-    let cxx_tool = binding.get(&target).unwrap();
+    let cxx_tool = build.cxx.get(&target).unwrap();
     assert_eq!(cxx_tool.path(), &PathBuf::from("dummy-cxx"));
-    let binding = build.ar.borrow();
-    let ar = binding.get(&target).unwrap();
+    let ar = build.ar.get(&target).unwrap();
     assert_eq!(ar, &PathBuf::from("dummy-ar"));
-    let binding = build.ranlib.borrow();
-    let ranlib = binding.get(&target).unwrap();
+    let ranlib = build.ranlib.get(&target).unwrap();
     assert_eq!(ranlib, &PathBuf::from("dummy-ranlib"));
 }
 
@@ -139,12 +131,12 @@ fn test_find_target_without_config() {
     let mut build = Build::new(Config { ..Config::parse(Flags::parse(&["build".to_owned()])) });
     let target = TargetSelection::from_user("x86_64-unknown-linux-gnu");
     build.config.target_config.clear();
-    find_target(&build, target.clone());
-    assert!(build.cc.borrow().contains_key(&target));
+    fill_target_compiler(&mut build, target.clone());
+    assert!(build.cc.contains_key(&target));
     if !target.triple.contains("vxworks") {
-        assert!(build.cxx.borrow().contains_key(&target));
+        assert!(build.cxx.contains_key(&target));
     }
-    assert!(build.ar.borrow().contains_key(&target));
+    assert!(build.ar.contains_key(&target));
 }
 
 #[test]
@@ -154,8 +146,8 @@ fn test_find() {
     let target2 = TargetSelection::from_user("x86_64-unknown-openbsd");
     build.targets.push(target1.clone());
     build.hosts.push(target2.clone());
-    find(&build);
-    for t in build.hosts.iter().chain(build.targets.iter()).chain(iter::once(&build.build)) {
-        assert!(build.cc.borrow().contains_key(t), "CC not set for target {}", t.triple);
+    fill_compilers(&mut build);
+    for t in build.hosts.iter().chain(build.targets.iter()).chain(iter::once(&build.host_target)) {
+        assert!(build.cc.contains_key(t), "CC not set for target {}", t.triple);
     }
 }
diff --git a/src/bootstrap/src/utils/change_tracker.rs b/src/bootstrap/src/utils/change_tracker.rs
index e939a8362ad..93e01a58077 100644
--- a/src/bootstrap/src/utils/change_tracker.rs
+++ b/src/bootstrap/src/utils/change_tracker.rs
@@ -421,4 +421,9 @@ pub const CONFIG_CHANGE_HISTORY: &[ChangeInfo] = &[
         severity: ChangeSeverity::Info,
         summary: "Added new bootstrap flag `--skip-std-check-if-no-download-rustc` that skips std checks when download-rustc is unavailable. Mainly intended for developers to reduce RA overhead.",
     },
+    ChangeInfo {
+        change_id: 142379,
+        severity: ChangeSeverity::Info,
+        summary: "Added new option `tool.TOOL_NAME.features` to specify the features to compile a tool with",
+    },
 ];
diff --git a/src/bootstrap/src/utils/channel.rs b/src/bootstrap/src/utils/channel.rs
index 4a9ecc7a4f8..38f250af42f 100644
--- a/src/bootstrap/src/utils/channel.rs
+++ b/src/bootstrap/src/utils/channel.rs
@@ -8,6 +8,7 @@
 use std::fs;
 use std::path::Path;
 
+use super::execution_context::ExecutionContext;
 use super::helpers;
 use crate::Build;
 use crate::utils::helpers::{start_process, t};
@@ -34,7 +35,7 @@ pub struct Info {
 }
 
 impl GitInfo {
-    pub fn new(omit_git_hash: bool, dir: &Path) -> GitInfo {
+    pub fn new(omit_git_hash: bool, dir: &Path, exec_ctx: impl AsRef<ExecutionContext>) -> GitInfo {
         // See if this even begins to look like a git dir
         if !dir.join(".git").exists() {
             match read_commit_info_file(dir) {
@@ -43,10 +44,12 @@ impl GitInfo {
             }
         }
 
-        // Make sure git commands work
-        match helpers::git(Some(dir)).arg("rev-parse").as_command_mut().output() {
-            Ok(ref out) if out.status.success() => {}
-            _ => return GitInfo::Absent,
+        let mut git_command = helpers::git(Some(dir));
+        git_command.arg("rev-parse");
+        let output = git_command.allow_failure().run_capture(exec_ctx);
+
+        if output.is_failure() {
+            return GitInfo::Absent;
         }
 
         // If we're ignoring the git info, we don't actually need to collect it, just make sure this
diff --git a/src/bootstrap/src/utils/exec.rs b/src/bootstrap/src/utils/exec.rs
index 64e46f10563..f297300e34a 100644
--- a/src/bootstrap/src/utils/exec.rs
+++ b/src/bootstrap/src/utils/exec.rs
@@ -11,7 +11,7 @@ use std::process::{Command, CommandArgs, CommandEnvs, ExitStatus, Output, Stdio}
 use build_helper::ci::CiEnv;
 use build_helper::drop_bomb::DropBomb;
 
-use crate::Build;
+use super::execution_context::ExecutionContext;
 
 /// What should be done when the command fails.
 #[derive(Debug, Copy, Clone)]
@@ -125,7 +125,6 @@ impl BootstrapCommand {
         Self { failure_behavior: BehaviorOnFailure::DelayFail, ..self }
     }
 
-    #[expect(dead_code)]
     pub fn fail_fast(self) -> Self {
         Self { failure_behavior: BehaviorOnFailure::Exit, ..self }
     }
@@ -143,20 +142,20 @@ impl BootstrapCommand {
     /// Run the command, while printing stdout and stderr.
     /// Returns true if the command has succeeded.
     #[track_caller]
-    pub fn run(&mut self, builder: &Build) -> bool {
-        builder.run(self, OutputMode::Print, OutputMode::Print).is_success()
+    pub fn run(&mut self, exec_ctx: impl AsRef<ExecutionContext>) -> bool {
+        exec_ctx.as_ref().run(self, OutputMode::Print, OutputMode::Print).is_success()
     }
 
     /// Run the command, while capturing and returning all its output.
     #[track_caller]
-    pub fn run_capture(&mut self, builder: &Build) -> CommandOutput {
-        builder.run(self, OutputMode::Capture, OutputMode::Capture)
+    pub fn run_capture(&mut self, exec_ctx: impl AsRef<ExecutionContext>) -> CommandOutput {
+        exec_ctx.as_ref().run(self, OutputMode::Capture, OutputMode::Capture)
     }
 
     /// Run the command, while capturing and returning stdout, and printing stderr.
     #[track_caller]
-    pub fn run_capture_stdout(&mut self, builder: &Build) -> CommandOutput {
-        builder.run(self, OutputMode::Capture, OutputMode::Print)
+    pub fn run_capture_stdout(&mut self, exec_ctx: impl AsRef<ExecutionContext>) -> CommandOutput {
+        exec_ctx.as_ref().run(self, OutputMode::Capture, OutputMode::Print)
     }
 
     /// Provides access to the stdlib Command inside.
@@ -280,7 +279,6 @@ impl CommandOutput {
         !self.is_success()
     }
 
-    #[expect(dead_code)]
     pub fn status(&self) -> Option<ExitStatus> {
         match self.status {
             CommandStatus::Finished(status) => Some(status),
diff --git a/src/bootstrap/src/utils/execution_context.rs b/src/bootstrap/src/utils/execution_context.rs
new file mode 100644
index 00000000000..a5e1e9bcc07
--- /dev/null
+++ b/src/bootstrap/src/utils/execution_context.rs
@@ -0,0 +1,204 @@
+//! Shared execution context for running bootstrap commands.
+//!
+//! This module provides the [`ExecutionContext`] type, which holds global configuration
+//! relevant during the execution of commands in bootstrap. This includes dry-run
+//! mode, verbosity level, and behavior on failure.
+use std::sync::{Arc, Mutex};
+
+use crate::core::config::DryRun;
+#[cfg(feature = "tracing")]
+use crate::trace_cmd;
+use crate::{BehaviorOnFailure, BootstrapCommand, CommandOutput, OutputMode, exit};
+
+#[derive(Clone, Default)]
+pub struct ExecutionContext {
+    dry_run: DryRun,
+    verbose: u8,
+    pub fail_fast: bool,
+    delayed_failures: Arc<Mutex<Vec<String>>>,
+}
+
+impl ExecutionContext {
+    pub fn new() -> Self {
+        ExecutionContext::default()
+    }
+
+    pub fn dry_run(&self) -> bool {
+        match self.dry_run {
+            DryRun::Disabled => false,
+            DryRun::SelfCheck | DryRun::UserSelected => true,
+        }
+    }
+
+    pub fn get_dry_run(&self) -> &DryRun {
+        &self.dry_run
+    }
+
+    pub fn verbose(&self, f: impl Fn()) {
+        if self.is_verbose() {
+            f()
+        }
+    }
+
+    pub fn is_verbose(&self) -> bool {
+        self.verbose > 0
+    }
+
+    pub fn fail_fast(&self) -> bool {
+        self.fail_fast
+    }
+
+    pub fn set_dry_run(&mut self, value: DryRun) {
+        self.dry_run = value;
+    }
+
+    pub fn set_verbose(&mut self, value: u8) {
+        self.verbose = value;
+    }
+
+    pub fn set_fail_fast(&mut self, value: bool) {
+        self.fail_fast = value;
+    }
+
+    pub fn add_to_delay_failure(&self, message: String) {
+        self.delayed_failures.lock().unwrap().push(message);
+    }
+
+    pub fn report_failures_and_exit(&self) {
+        let failures = self.delayed_failures.lock().unwrap();
+        if failures.is_empty() {
+            return;
+        }
+        eprintln!("\n{} command(s) did not execute successfully:\n", failures.len());
+        for failure in &*failures {
+            eprintln!("  - {failure}");
+        }
+        exit!(1);
+    }
+
+    /// Execute a command and return its output.
+    /// Note: Ideally, you should use one of the BootstrapCommand::run* functions to
+    /// execute commands. They internally call this method.
+    #[track_caller]
+    pub fn run(
+        &self,
+        command: &mut BootstrapCommand,
+        stdout: OutputMode,
+        stderr: OutputMode,
+    ) -> CommandOutput {
+        command.mark_as_executed();
+        if self.dry_run() && !command.run_always {
+            return CommandOutput::default();
+        }
+
+        #[cfg(feature = "tracing")]
+        let _run_span = trace_cmd!(command);
+
+        let created_at = command.get_created_location();
+        let executed_at = std::panic::Location::caller();
+
+        self.verbose(|| {
+            println!("running: {command:?} (created at {created_at}, executed at {executed_at})")
+        });
+
+        let cmd = command.as_command_mut();
+        cmd.stdout(stdout.stdio());
+        cmd.stderr(stderr.stdio());
+
+        let output = cmd.output();
+
+        use std::fmt::Write;
+
+        let mut message = String::new();
+        let output: CommandOutput = match output {
+            // Command has succeeded
+            Ok(output) if output.status.success() => {
+                CommandOutput::from_output(output, stdout, stderr)
+            }
+            // Command has started, but then it failed
+            Ok(output) => {
+                writeln!(
+                    message,
+                    r#"
+Command {command:?} did not execute successfully.
+Expected success, got {}
+Created at: {created_at}
+Executed at: {executed_at}"#,
+                    output.status,
+                )
+                .unwrap();
+
+                let output: CommandOutput = CommandOutput::from_output(output, stdout, stderr);
+
+                // If the output mode is OutputMode::Capture, we can now print the output.
+                // If it is OutputMode::Print, then the output has already been printed to
+                // stdout/stderr, and we thus don't have anything captured to print anyway.
+                if stdout.captures() {
+                    writeln!(message, "\nSTDOUT ----\n{}", output.stdout().trim()).unwrap();
+                }
+                if stderr.captures() {
+                    writeln!(message, "\nSTDERR ----\n{}", output.stderr().trim()).unwrap();
+                }
+                output
+            }
+            // The command did not even start
+            Err(e) => {
+                writeln!(
+                    message,
+                    "\n\nCommand {command:?} did not execute successfully.\
+            \nIt was not possible to execute the command: {e:?}"
+                )
+                .unwrap();
+                CommandOutput::did_not_start(stdout, stderr)
+            }
+        };
+
+        let fail = |message: &str, output: CommandOutput| -> ! {
+            if self.is_verbose() {
+                println!("{message}");
+            } else {
+                let (stdout, stderr) = (output.stdout_if_present(), output.stderr_if_present());
+                // If the command captures output, the user would not see any indication that
+                // it has failed. In this case, print a more verbose error, since to provide more
+                // context.
+                if stdout.is_some() || stderr.is_some() {
+                    if let Some(stdout) =
+                        output.stdout_if_present().take_if(|s| !s.trim().is_empty())
+                    {
+                        println!("STDOUT:\n{stdout}\n");
+                    }
+                    if let Some(stderr) =
+                        output.stderr_if_present().take_if(|s| !s.trim().is_empty())
+                    {
+                        println!("STDERR:\n{stderr}\n");
+                    }
+                    println!("Command {command:?} has failed. Rerun with -v to see more details.");
+                } else {
+                    println!("Command has failed. Rerun with -v to see more details.");
+                }
+            }
+            exit!(1);
+        };
+
+        if !output.is_success() {
+            match command.failure_behavior {
+                BehaviorOnFailure::DelayFail => {
+                    if self.fail_fast {
+                        fail(&message, output);
+                    }
+
+                    self.add_to_delay_failure(message);
+                }
+                BehaviorOnFailure::Exit => {
+                    fail(&message, output);
+                }
+                BehaviorOnFailure::Ignore => {
+                    // If failures are allowed, either the error has been printed already
+                    // (OutputMode::Print) or the user used a capture output mode and wants to
+                    // handle the error output on their own.
+                }
+            }
+        }
+        output
+    }
+}
diff --git a/src/bootstrap/src/utils/helpers.rs b/src/bootstrap/src/utils/helpers.rs
index f2c3e8c0df4..f4be22f1e64 100644
--- a/src/bootstrap/src/utils/helpers.rs
+++ b/src/bootstrap/src/utils/helpers.rs
@@ -98,7 +98,7 @@ pub fn is_dylib(path: &Path) -> bool {
 
 /// Return the path to the containing submodule if available.
 pub fn submodule_path_of(builder: &Builder<'_>, path: &str) -> Option<String> {
-    let submodule_paths = build_helper::util::parse_gitmodules(&builder.src);
+    let submodule_paths = builder.submodule_paths();
     submodule_paths.iter().find_map(|submodule_path| {
         if path.starts_with(submodule_path) { Some(submodule_path.to_string()) } else { None }
     })
@@ -270,24 +270,6 @@ pub fn is_valid_test_suite_arg<'a, P: AsRef<Path>>(
     }
 }
 
-// FIXME: get rid of this function
-pub fn check_run(cmd: &mut BootstrapCommand, print_cmd_on_fail: bool) -> bool {
-    let status = match cmd.as_command_mut().status() {
-        Ok(status) => status,
-        Err(e) => {
-            println!("failed to execute command: {cmd:?}\nERROR: {e}");
-            return false;
-        }
-    };
-    if !status.success() && print_cmd_on_fail {
-        println!(
-            "\n\ncommand did not execute successfully: {cmd:?}\n\
-             expected success, got: {status}\n\n"
-        );
-    }
-    status.success()
-}
-
 pub fn make(host: &str) -> PathBuf {
     if host.contains("dragonfly")
         || host.contains("freebsd")
@@ -300,25 +282,6 @@ pub fn make(host: &str) -> PathBuf {
     }
 }
 
-#[track_caller]
-pub fn output(cmd: &mut Command) -> String {
-    #[cfg(feature = "tracing")]
-    let _run_span = crate::trace_cmd!(cmd);
-
-    let output = match cmd.stderr(Stdio::inherit()).output() {
-        Ok(status) => status,
-        Err(e) => fail(&format!("failed to execute command: {cmd:?}\nERROR: {e}")),
-    };
-    if !output.status.success() {
-        panic!(
-            "command did not execute successfully: {:?}\n\
-             expected success, got: {}",
-            cmd, output.status
-        );
-    }
-    String::from_utf8(output.stdout).unwrap()
-}
-
 /// Spawn a process and return a closure that will wait for the process
 /// to finish and then return its output. This allows the spawned process
 /// to do work without immediately blocking bootstrap.
diff --git a/src/bootstrap/src/utils/mod.rs b/src/bootstrap/src/utils/mod.rs
index 169fcec303e..5a0b90801e7 100644
--- a/src/bootstrap/src/utils/mod.rs
+++ b/src/bootstrap/src/utils/mod.rs
@@ -8,6 +8,7 @@ pub(crate) mod cc_detect;
 pub(crate) mod change_tracker;
 pub(crate) mod channel;
 pub(crate) mod exec;
+pub(crate) mod execution_context;
 pub(crate) mod helpers;
 pub(crate) mod job;
 pub(crate) mod render_tests;
diff --git a/src/bootstrap/src/utils/render_tests.rs b/src/bootstrap/src/utils/render_tests.rs
index 418f3ff975d..77e645a9e3c 100644
--- a/src/bootstrap/src/utils/render_tests.rs
+++ b/src/bootstrap/src/utils/render_tests.rs
@@ -43,8 +43,7 @@ pub(crate) fn try_run_tests(
         if builder.fail_fast {
             crate::exit!(1);
         } else {
-            let mut failures = builder.delayed_failures.borrow_mut();
-            failures.push(format!("{cmd:?}"));
+            builder.config.exec_ctx().add_to_delay_failure(format!("{cmd:?}"));
             false
         }
     } else {
diff --git a/src/bootstrap/src/utils/shared_helpers.rs b/src/bootstrap/src/utils/shared_helpers.rs
index 561af34a447..9c6b4a7615d 100644
--- a/src/bootstrap/src/utils/shared_helpers.rs
+++ b/src/bootstrap/src/utils/shared_helpers.rs
@@ -6,6 +6,9 @@
 
 #![allow(dead_code)]
 
+#[cfg(test)]
+mod tests;
+
 use std::env;
 use std::ffi::OsString;
 use std::fs::OpenOptions;
diff --git a/src/bootstrap/src/utils/tests/shared_helpers_tests.rs b/src/bootstrap/src/utils/shared_helpers/tests.rs
index 6c47e7f2438..559e9f70abd 100644
--- a/src/bootstrap/src/utils/tests/shared_helpers_tests.rs
+++ b/src/bootstrap/src/utils/shared_helpers/tests.rs
@@ -1,10 +1,3 @@
-//! The `shared_helpers` module can't have its own tests submodule, because
-//! that would cause problems for the shim binaries that include it via
-//! `#[path]`, so instead those unit tests live here.
-//!
-//! To prevent tidy from complaining about this file not being named `tests.rs`,
-//! it lives inside a submodule directory named `tests`.
-
 use crate::utils::shared_helpers::parse_value_from_args;
 
 #[test]
diff --git a/src/bootstrap/src/utils/tests/mod.rs b/src/bootstrap/src/utils/tests/mod.rs
index 73d55db994c..73c500f6e36 100644
--- a/src/bootstrap/src/utils/tests/mod.rs
+++ b/src/bootstrap/src/utils/tests/mod.rs
@@ -1,2 +1,3 @@
+//! This module contains shared utilities for bootstrap tests.
+
 pub mod git;
-mod shared_helpers_tests;
diff --git a/src/build_helper/src/lib.rs b/src/build_helper/src/lib.rs
index 1f5cf723641..05de8fd2d42 100644
--- a/src/build_helper/src/lib.rs
+++ b/src/build_helper/src/lib.rs
@@ -6,6 +6,7 @@ pub mod fs;
 pub mod git;
 pub mod metrics;
 pub mod stage0_parser;
+pub mod targets;
 pub mod util;
 
 /// The default set of crates for opt-dist to collect LLVM profiles.
diff --git a/src/build_helper/src/targets.rs b/src/build_helper/src/targets.rs
new file mode 100644
index 00000000000..cccc413368b
--- /dev/null
+++ b/src/build_helper/src/targets.rs
@@ -0,0 +1,11 @@
+// FIXME(#142296): this hack is because there is no reliable way (yet) to determine whether a given
+// target supports std. In the long-term, we should try to implement a way to *reliably* determine
+// target (std) metadata.
+//
+// NOTE: this is pulled out to `build_helpers` to share this hack between `bootstrap` and
+// `compiletest`.
+pub fn target_supports_std(target_tuple: &str) -> bool {
+    !(target_tuple.contains("-none")
+        || target_tuple.contains("nvptx")
+        || target_tuple.contains("switch"))
+}
diff --git a/src/build_helper/src/util.rs b/src/build_helper/src/util.rs
index 72c05c4c48a..80dd6813d13 100644
--- a/src/build_helper/src/util.rs
+++ b/src/build_helper/src/util.rs
@@ -2,7 +2,6 @@ use std::fs::File;
 use std::io::{BufRead, BufReader};
 use std::path::Path;
 use std::process::Command;
-use std::sync::OnceLock;
 
 /// Invokes `build_helper::util::detail_exit` with `cfg!(test)`
 ///
@@ -51,25 +50,20 @@ pub fn try_run(cmd: &mut Command, print_cmd_on_fail: bool) -> Result<(), ()> {
 }
 
 /// Returns the submodule paths from the `.gitmodules` file in the given directory.
-pub fn parse_gitmodules(target_dir: &Path) -> &[String] {
-    static SUBMODULES_PATHS: OnceLock<Vec<String>> = OnceLock::new();
+pub fn parse_gitmodules(target_dir: &Path) -> Vec<String> {
     let gitmodules = target_dir.join(".gitmodules");
     assert!(gitmodules.exists(), "'{}' file is missing.", gitmodules.display());
 
-    let init_submodules_paths = || {
-        let file = File::open(gitmodules).unwrap();
+    let file = File::open(gitmodules).unwrap();
 
-        let mut submodules_paths = vec![];
-        for line in BufReader::new(file).lines().map_while(Result::ok) {
-            let line = line.trim();
-            if line.starts_with("path") {
-                let actual_path = line.split(' ').last().expect("Couldn't get value of path");
-                submodules_paths.push(actual_path.to_owned());
-            }
+    let mut submodules_paths = vec![];
+    for line in BufReader::new(file).lines().map_while(Result::ok) {
+        let line = line.trim();
+        if line.starts_with("path") {
+            let actual_path = line.split(' ').last().expect("Couldn't get value of path");
+            submodules_paths.push(actual_path.to_owned());
         }
+    }
 
-        submodules_paths
-    };
-
-    SUBMODULES_PATHS.get_or_init(|| init_submodules_paths())
+    submodules_paths
 }
diff --git a/src/ci/citool/src/jobs.rs b/src/ci/citool/src/jobs.rs
index 2884ae08ea8..81e002edb15 100644
--- a/src/ci/citool/src/jobs.rs
+++ b/src/ci/citool/src/jobs.rs
@@ -161,6 +161,8 @@ pub enum RunType {
     TryJob { job_patterns: Option<Vec<String>> },
     /// Merge attempt workflow
     AutoJob,
+    /// Fake job only used for sharing Github Actions cache.
+    MasterJob,
 }
 
 /// Maximum number of custom try jobs that can be requested in a single
@@ -210,6 +212,7 @@ fn calculate_jobs(
             (jobs, "try", &db.envs.try_env)
         }
         RunType::AutoJob => (db.auto_jobs.clone(), "auto", &db.envs.auto_env),
+        RunType::MasterJob => return Ok(vec![]),
     };
     let jobs = substitute_github_vars(jobs.clone())
         .context("Failed to substitute GitHub context variables in jobs")?;
@@ -262,7 +265,7 @@ pub fn calculate_job_matrix(
     eprintln!("Run type: {run_type:?}");
 
     let jobs = calculate_jobs(&run_type, &db, channel)?;
-    if jobs.is_empty() {
+    if jobs.is_empty() && !matches!(run_type, RunType::MasterJob) {
         return Err(anyhow::anyhow!("Computed job list is empty"));
     }
 
@@ -270,6 +273,7 @@ pub fn calculate_job_matrix(
         RunType::PullRequest => "pr",
         RunType::TryJob { .. } => "try",
         RunType::AutoJob => "auto",
+        RunType::MasterJob => "master",
     };
 
     eprintln!("Output");
diff --git a/src/ci/citool/src/main.rs b/src/ci/citool/src/main.rs
index bb73a5ef909..fe1b36673a1 100644
--- a/src/ci/citool/src/main.rs
+++ b/src/ci/citool/src/main.rs
@@ -47,6 +47,7 @@ impl GitHubContext {
                 Some(RunType::TryJob { job_patterns: patterns })
             }
             ("push", "refs/heads/auto") => Some(RunType::AutoJob),
+            ("push", "refs/heads/master") => Some(RunType::MasterJob),
             _ => None,
         }
     }
diff --git a/src/ci/citool/tests/jobs.rs b/src/ci/citool/tests/jobs.rs
index fcdca899e06..83f2fc0ed1f 100644
--- a/src/ci/citool/tests/jobs.rs
+++ b/src/ci/citool/tests/jobs.rs
@@ -45,17 +45,31 @@ fn pr_jobs() {
     "#);
 }
 
+#[test]
+fn master_jobs() {
+    let stdout = get_matrix("push", "commit", "refs/heads/master");
+    insta::assert_snapshot!(stdout, @r#"
+    jobs=[]
+    run_type=master
+    "#);
+}
+
 fn get_matrix(event_name: &str, commit_msg: &str, branch_ref: &str) -> String {
-    let output = Command::new("cargo")
-        .args(["run", "-q", "calculate-job-matrix", "--jobs-file", TEST_JOBS_YML_PATH])
+    let path = std::env::var("PATH");
+    let mut cmd = Command::new("cargo");
+    cmd.args(["run", "-q", "calculate-job-matrix", "--jobs-file", TEST_JOBS_YML_PATH])
+        .env_clear()
         .env("GITHUB_EVENT_NAME", event_name)
         .env("COMMIT_MESSAGE", commit_msg)
         .env("GITHUB_REF", branch_ref)
         .env("GITHUB_RUN_ID", "123")
         .env("GITHUB_RUN_ATTEMPT", "1")
-        .stdout(Stdio::piped())
-        .output()
-        .expect("Failed to execute command");
+        .stdout(Stdio::piped());
+    if let Ok(path) = path {
+        cmd.env("PATH", path);
+    }
+
+    let output = cmd.output().expect("Failed to execute command");
 
     let stdout = String::from_utf8(output.stdout).unwrap();
     let stderr = String::from_utf8(output.stderr).unwrap();
diff --git a/src/ci/docker/host-x86_64/i686-gnu-nopt/Dockerfile b/src/ci/docker/host-x86_64/i686-gnu-nopt/Dockerfile
index 241199d3baf..58e66fd637a 100644
--- a/src/ci/docker/host-x86_64/i686-gnu-nopt/Dockerfile
+++ b/src/ci/docker/host-x86_64/i686-gnu-nopt/Dockerfile
@@ -22,10 +22,6 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
 COPY scripts/sccache.sh /scripts/
 RUN sh /scripts/sccache.sh
 
-RUN mkdir -p /config
-RUN echo "[rust]" > /config/nopt-std-config.toml
-RUN echo "optimize = false" >> /config/nopt-std-config.toml
-
 ENV RUST_CONFIGURE_ARGS --build=i686-unknown-linux-gnu --disable-optimize-tests
 ARG SCRIPT_ARG
 COPY scripts/stage_2_test_set1.sh /scripts/
diff --git a/src/ci/docker/host-x86_64/mingw-check-2/Dockerfile b/src/ci/docker/host-x86_64/mingw-check-2/Dockerfile
index a1d04bd984c..ce18a181d31 100644
--- a/src/ci/docker/host-x86_64/mingw-check-2/Dockerfile
+++ b/src/ci/docker/host-x86_64/mingw-check-2/Dockerfile
@@ -36,4 +36,7 @@ ENV SCRIPT \
         RUSTDOCFLAGS=\"--document-private-items --document-hidden-items\" python3 ../x.py doc --stage 1 library && \
         mkdir -p /checkout/obj/staging/doc && \
         cp -r build/x86_64-unknown-linux-gnu/doc /checkout/obj/staging && \
-        RUSTDOCFLAGS=\"--document-private-items --document-hidden-items\" python3 ../x.py doc --stage 1 library/test
+        RUSTDOCFLAGS=\"--document-private-items --document-hidden-items\" python3 ../x.py doc --stage 1 library/test && \
+        # The BOOTSTRAP_TRACING flag is added to verify whether the 
+        # bootstrap process compiles successfully with this flag enabled.
+        BOOTSTRAP_TRACING=1 python3 ../x.py --help
diff --git a/src/ci/docker/host-x86_64/mingw-check-tidy/Dockerfile b/src/ci/docker/host-x86_64/mingw-check-tidy/Dockerfile
index 006a697af21..8d2c5e004e4 100644
--- a/src/ci/docker/host-x86_64/mingw-check-tidy/Dockerfile
+++ b/src/ci/docker/host-x86_64/mingw-check-tidy/Dockerfile
@@ -41,7 +41,9 @@ RUN pip3 install --no-deps --no-cache-dir --require-hashes -r /tmp/reuse-require
 COPY host-x86_64/mingw-check-1/validate-toolstate.sh /scripts/
 COPY host-x86_64/mingw-check-1/validate-error-codes.sh /scripts/
 
+RUN bash -c 'npm install -g eslint@$(cat /tmp/eslint.version)'
+
 # NOTE: intentionally uses python2 for x.py so we can test it still works.
 # validate-toolstate only runs in our CI, so it's ok for it to only support python3.
-ENV SCRIPT TIDY_PRINT_DIFF=1 npm install eslint@$(head -n 1 /tmp/eslint.version) && \
- python2.7 ../x.py test --stage 0 src/tools/tidy tidyselftest --extra-checks=py,cpp
+ENV SCRIPT TIDY_PRINT_DIFF=1 python2.7 ../x.py test --stage 0 \
+    src/tools/tidy tidyselftest --extra-checks=py,cpp
diff --git a/src/ci/docker/host-x86_64/x86_64-gnu-nopt/Dockerfile b/src/ci/docker/host-x86_64/x86_64-gnu-nopt/Dockerfile
index 1b57ae7c8da..854c36ee01c 100644
--- a/src/ci/docker/host-x86_64/x86_64-gnu-nopt/Dockerfile
+++ b/src/ci/docker/host-x86_64/x86_64-gnu-nopt/Dockerfile
@@ -22,12 +22,8 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
 COPY scripts/sccache.sh /scripts/
 RUN sh /scripts/sccache.sh
 
-RUN mkdir -p /config
-RUN echo "[rust]" > /config/nopt-std-config.toml
-RUN echo "optimize = false" >> /config/nopt-std-config.toml
-
 ENV RUST_CONFIGURE_ARGS --build=x86_64-unknown-linux-gnu \
   --disable-optimize-tests \
   --set rust.test-compare-mode
-ENV SCRIPT python3 ../x.py test --stage 1 --config /config/nopt-std-config.toml library/std \
+ENV SCRIPT python3 ../x.py test --stage 1 --set rust.optimize=false library/std \
   && python3 ../x.py --stage 2 test
diff --git a/src/ci/github-actions/jobs.yml b/src/ci/github-actions/jobs.yml
index 43c77d1ddf7..217cf764afb 100644
--- a/src/ci/github-actions/jobs.yml
+++ b/src/ci/github-actions/jobs.yml
@@ -256,7 +256,7 @@ auto:
       IMAGE: dist-x86_64-linux
       CODEGEN_BACKENDS: llvm,cranelift
       DOCKER_SCRIPT: dist-alt.sh
-    <<: *job-linux-4c-largedisk
+    <<: *job-linux-8c
 
   - name: dist-x86_64-musl
     env:
@@ -300,7 +300,7 @@ auto:
     env:
       IMAGE: i686-gnu-nopt
       DOCKER_SCRIPT: >-
-        python3 ../x.py test --stage 1 --config /config/nopt-std-config.toml library/std &&
+        python3 ../x.py test --stage 1 --set rust.optimize=false library/std &&
         /scripts/stage_2_test_set2.sh
     <<: *job-linux-4c
 
diff --git a/src/ci/run.sh b/src/ci/run.sh
index b6143af632d..a6721a818b3 100755
--- a/src/ci/run.sh
+++ b/src/ci/run.sh
@@ -134,6 +134,11 @@ if [ "$DEPLOY$DEPLOY_ALT" = "1" ]; then
 
   CODEGEN_BACKENDS="${CODEGEN_BACKENDS:-llvm}"
   RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --set rust.codegen-backends=$CODEGEN_BACKENDS"
+
+  # Unless explicitly disabled, we want rustc debug assertions on the -alt builds
+  if [ "$DEPLOY_ALT" != "" ] && [ "$NO_DEBUG_ASSERTIONS" = "" ]; then
+    RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --enable-debug-assertions"
+  fi
 else
   # We almost always want debug assertions enabled, but sometimes this takes too
   # long for too little benefit, so we just turn them off.
@@ -186,9 +191,11 @@ else
   # Download GCC from CI on test builders
   RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --set gcc.download-ci-gcc=true"
 
-  if [ "$NO_DOWNLOAD_CI_RUSTC" = "" ]; then
-    RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --set rust.download-rustc=if-unchanged"
-  fi
+  # download-rustc seems to be broken on CI after the stage0 redesign
+  # Disable it until these issues are debugged and resolved
+#  if [ "$NO_DOWNLOAD_CI_RUSTC" = "" ]; then
+#    RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --set rust.download-rustc=if-unchanged"
+#  fi
 fi
 
 if [ "$ENABLE_GCC_CODEGEN" = "1" ]; then
diff --git a/src/doc/book b/src/doc/book
-Subproject 634724ea85ebb08a542970bf8871ac8b0f77fd1
+Subproject 4433c9f0cad8460bee05ede040587f8a1fa3f1d
diff --git a/src/doc/reference b/src/doc/reference
-Subproject 8e0f593a30f3b56ddb0908fb7ab9249974e0873
+Subproject d4c66b346f4b72d29e70390a3fa3ea7d4e064db
diff --git a/src/doc/rust-by-example b/src/doc/rust-by-example
-Subproject 21f4e32b8b40d36453fae16ec07ad4b857c445b
+Subproject 9baa9e863116cb9524a177d5a5c475baac18928
diff --git a/src/doc/rustc-dev-guide/rust-version b/src/doc/rustc-dev-guide/rust-version
index 8b48bd518bd..86d35b31498 100644
--- a/src/doc/rustc-dev-guide/rust-version
+++ b/src/doc/rustc-dev-guide/rust-version
@@ -1 +1 @@
-c68032fd4c442d275f4daa571ba19c076106b490
+14346303d760027e53214e705109a62c0f00b214
diff --git a/src/doc/rustc-dev-guide/src/SUMMARY.md b/src/doc/rustc-dev-guide/src/SUMMARY.md
index a7b76233d19..cba8eac617d 100644
--- a/src/doc/rustc-dev-guide/src/SUMMARY.md
+++ b/src/doc/rustc-dev-guide/src/SUMMARY.md
@@ -63,10 +63,8 @@
 - [Notification groups](notification-groups/about.md)
     - [Apple](notification-groups/apple.md)
     - [ARM](notification-groups/arm.md)
-    - [Cleanup Crew](notification-groups/cleanup-crew.md)
     - [Emscripten](notification-groups/emscripten.md)
     - [Fuchsia](notification-groups/fuchsia.md)
-    - [LLVM](notification-groups/llvm.md)
     - [RISC-V](notification-groups/risc-v.md)
     - [Rust for Linux](notification-groups/rust-for-linux.md)
     - [WASI](notification-groups/wasi.md)
@@ -101,6 +99,8 @@
 - [Rustdoc internals](./rustdoc-internals.md)
     - [Search](./rustdoc-internals/search.md)
 	- [The `rustdoc` test suite](./rustdoc-internals/rustdoc-test-suite.md)
+	- [The `rustdoc-gui` test suite](./rustdoc-internals/rustdoc-gui-test-suite.md)
+	- [The `rustdoc-json` test suite](./rustdoc-internals/rustdoc-json-test-suite.md)
 - [Autodiff internals](./autodiff/internals.md)
     - [Installation](./autodiff/installation.md)
     - [How to debug](./autodiff/debugging.md)
diff --git a/src/doc/rustc-dev-guide/src/building/bootstrapping/debugging-bootstrap.md b/src/doc/rustc-dev-guide/src/building/bootstrapping/debugging-bootstrap.md
index 35d33ebdb0e..ed267850401 100644
--- a/src/doc/rustc-dev-guide/src/building/bootstrapping/debugging-bootstrap.md
+++ b/src/doc/rustc-dev-guide/src/building/bootstrapping/debugging-bootstrap.md
@@ -55,7 +55,7 @@ Bootstrap will conditionally build `tracing` support and enable `tracing` output
 
 Example basic usage[^just-trace]:
 
-[^just-trace]: It is not recommend to use *just* `BOOTSTRAP_TRACING=TRACE` because that will dump *everything* at `TRACE` level, including logs intentionally gated behind custom targets as they are too verbose even for `TRACE` level by default.
+[^just-trace]: It is not recommended to use *just* `BOOTSTRAP_TRACING=TRACE` because that will dump *everything* at `TRACE` level, including logs intentionally gated behind custom targets as they are too verbose even for `TRACE` level by default.
 
 ```bash
 $ BOOTSTRAP_TRACING=bootstrap=TRACE ./x build library --stage 1
diff --git a/src/doc/rustc-dev-guide/src/getting-started.md b/src/doc/rustc-dev-guide/src/getting-started.md
index 435202ca6c8..d6c5c3ac852 100644
--- a/src/doc/rustc-dev-guide/src/getting-started.md
+++ b/src/doc/rustc-dev-guide/src/getting-started.md
@@ -158,9 +158,6 @@ feel comfortable jumping straight into the large `rust-lang/rust` codebase.
 The following tasks are doable without much background knowledge but are
 incredibly helpful:
 
-- [Cleanup crew][iceb]: find minimal reproductions of ICEs, bisect
-  regressions, etc. This is a way of helping that saves a ton of time for
-  others to fix an error later.
 - [Writing documentation][wd]: if you are feeling a bit more intrepid, you could try
   to read a part of the code and write doc comments for it. This will help you
   to learn some part of the compiler while also producing a useful artifact!
@@ -179,7 +176,6 @@ incredibly helpful:
 [users]: https://users.rust-lang.org/
 [so]: http://stackoverflow.com/questions/tagged/rust
 [community-library]: https://github.com/rust-lang/rfcs/labels/A-community-library
-[iceb]: ./notification-groups/cleanup-crew.md
 [wd]: ./contributing.md#writing-documentation
 [wg]: https://rust-lang.github.io/compiler-team/working-groups/
 [triage]: ./contributing.md#issue-triage
diff --git a/src/doc/rustc-dev-guide/src/git.md b/src/doc/rustc-dev-guide/src/git.md
index 8118ddff10c..8726ddfce20 100644
--- a/src/doc/rustc-dev-guide/src/git.md
+++ b/src/doc/rustc-dev-guide/src/git.md
@@ -142,7 +142,8 @@ The most common cause is that you rebased after a change and ran `git add .` wit
 `x` to update the submodules.  Alternatively, you might have run `cargo fmt` instead of `x fmt`
 and modified files in a submodule, then committed the changes.
 
-To fix it, do the following things:
+To fix it, do the following things (if you changed a submodule other than cargo,
+replace `src/tools/cargo` with the path to that submodule):
 
 1. See which commit has the accidental changes: `git log --stat -n1 src/tools/cargo`
 2. Revert the changes to that commit: `git checkout <my-commit>~ src/tools/cargo`. Type `~`
diff --git a/src/doc/rustc-dev-guide/src/implementing_new_features.md b/src/doc/rustc-dev-guide/src/implementing_new_features.md
index d7561bbbad2..5d0e875cbc1 100644
--- a/src/doc/rustc-dev-guide/src/implementing_new_features.md
+++ b/src/doc/rustc-dev-guide/src/implementing_new_features.md
@@ -156,8 +156,8 @@ a new unstable feature:
    [`incomplete_features` lint]: https://doc.rust-lang.org/rustc/lints/listing/warn-by-default.html#incomplete-features
 
    ```rust ignore
-   /// Allows unsized rvalues at arguments and parameters.
-   (incomplete, unsized_locals, "CURRENT_RUSTC_VERSION", Some(48055), None),
+   /// Allows deref patterns.
+   (incomplete, deref_patterns, "CURRENT_RUSTC_VERSION", Some(87121), None),
    ```
 
    To avoid [semantic merge conflicts], please use `CURRENT_RUSTC_VERSION` instead of `1.70` or
diff --git a/src/doc/rustc-dev-guide/src/notification-groups/about.md b/src/doc/rustc-dev-guide/src/notification-groups/about.md
index af305f0103a..d75891ecf7b 100644
--- a/src/doc/rustc-dev-guide/src/notification-groups/about.md
+++ b/src/doc/rustc-dev-guide/src/notification-groups/about.md
@@ -21,9 +21,7 @@ search for existing issues that haven't been claimed yet.
 Here's the list of the notification groups:
 - [Apple](./apple.md)
 - [ARM](./arm.md)
-- [Cleanup Crew](./cleanup-crew.md)
 - [Emscripten](./emscripten.md)
-- [LLVM Icebreakers](./llvm.md)
 - [RISC-V](./risc-v.md)
 - [WASI](./wasi.md)
 - [WebAssembly](./wasm.md)
@@ -64,9 +62,7 @@ Example PRs:
 
 * [Example of adding yourself to the Apple group.](https://github.com/rust-lang/team/pull/1434)
 * [Example of adding yourself to the ARM group.](https://github.com/rust-lang/team/pull/358)
-* [Example of adding yourself to the Cleanup Crew.](https://github.com/rust-lang/team/pull/221)
 * [Example of adding yourself to the Emscripten group.](https://github.com/rust-lang/team/pull/1579)
-* [Example of adding yourself to the LLVM group.](https://github.com/rust-lang/team/pull/140)
 * [Example of adding yourself to the RISC-V group.](https://github.com/rust-lang/team/pull/394)
 * [Example of adding yourself to the WASI group.](https://github.com/rust-lang/team/pull/1580)
 * [Example of adding yourself to the WebAssembly group.](https://github.com/rust-lang/team/pull/1581)
@@ -81,9 +77,7 @@ group. For example:
 ```text
 @rustbot ping apple
 @rustbot ping arm
-@rustbot ping cleanup-crew
 @rustbot ping emscripten
-@rustbot ping icebreakers-llvm
 @rustbot ping risc-v
 @rustbot ping wasi
 @rustbot ping wasm
@@ -92,12 +86,12 @@ group. For example:
 
 To make some commands shorter and easier to remember, there are aliases,
 defined in the [`triagebot.toml`] file. For example, all of these commands
-are equivalent and will ping the Cleanup Crew:
+are equivalent and will ping the Apple group:
 
 ```text
-@rustbot ping cleanup
-@rustbot ping bisect
-@rustbot ping reduce
+@rustbot ping apple
+@rustbot ping macos
+@rustbot ping ios
 ```
 
 Keep in mind that these aliases are meant to make humans' life easier.
diff --git a/src/doc/rustc-dev-guide/src/notification-groups/cleanup-crew.md b/src/doc/rustc-dev-guide/src/notification-groups/cleanup-crew.md
deleted file mode 100644
index 9cf4e512cbd..00000000000
--- a/src/doc/rustc-dev-guide/src/notification-groups/cleanup-crew.md
+++ /dev/null
@@ -1,90 +0,0 @@
-# Cleanup Crew
-
-**Github Label:** [ICEBreaker-Cleanup-Crew] <br>
-**Ping command:** `@rustbot ping cleanup-crew`
-
-[ICEBreaker-Cleanup-Crew]: https://github.com/rust-lang/rust/labels/ICEBreaker-Cleanup-Crew
-
-The "Cleanup Crew" are focused on improving bug reports. Specifically,
-the goal is to try to ensure that every bug report has all the
-information that will be needed for someone to fix it:
-
-* a minimal, standalone example that shows the problem
-* links to duplicates or related bugs
-* if the bug is a regression (something that used to work, but no longer does),
-  then a bisection to the PR or nightly that caused the regression
-
-This kind of cleanup is invaluable in getting bugs fixed. Better
-still, it can be done by anybody who knows Rust, without any
-particularly deep knowledge of the compiler.
-
-Let's look a bit at the workflow for doing "cleanup crew" actions.
-
-## Finding a minimal, standalone example
-
-Here the ultimate goal is to produce an example that reproduces the same
-problem but without relying on any external crates. Such a test ought to contain
-as little code as possible, as well. This will make it much easier to isolate the problem.
-
-However, even if the "ultimate minimal test" cannot be achieved, it's
-still useful to post incremental minimizations. For example, if you
-can eliminate some of the external dependencies, that is helpful, and
-so forth. 
-
-It's particularly useful to reduce to an example that works
-in the [Rust playground](https://play.rust-lang.org/), rather than
-requiring people to checkout a cargo build.
-
-There are many resources for how to produce minimized test cases. Here
-are a few:
-
-* The [rust-reduce](https://github.com/jethrogb/rust-reduce) tool can try to reduce
-  code automatically.
-  * The [C-reduce](https://github.com/csmith-project/creduce) tool also works
-    on Rust code, though it requires that you start from a single
-    file. (A post explaining how to do it can be found [here](https://insaneinside.net/2017/09/12/whole-crate-bug-reduction-with-creduce.html).)
-* pnkfelix's [Rust Bug Minimization Patterns] blog post
-  * This post focuses on "heavy bore" techniques, where you are
-    starting with a large, complex cargo project that you wish to
-    narrow down to something standalone.
-
-[Rust Bug Minimization Patterns]: http://blog.pnkfx.org/blog/2019/11/18/rust-bug-minimization-patterns/
-
-## Links to duplicate or related bugs
-
-If you are on the "Cleanup Crew", you will sometimes see multiple bug
-reports that seem very similar. You can link one to the other just by
-mentioning the other bug number in a Github comment. Sometimes it is
-useful to close duplicate bugs. But if you do so, you should always
-copy any test case from the bug you are closing to the other bug that
-remains open, as sometimes duplicate-looking bugs will expose
-different facets of the same problem.
-
-## Bisecting regressions
-
-For regressions (something that used to work, but no longer does), it
-is super useful if we can figure out precisely when the code stopped
-working.  The gold standard is to be able to identify the precise
-**PR** that broke the code, so we can ping the author, but even
-narrowing it down to a nightly build is helpful, especially as that
-then gives us a range of PRs. (One other challenge is that we
-sometimes land "rollup" PRs, which combine multiple PRs into one.)
-
-### cargo-bisect-rustc
-
-To help in figuring out the cause of a regression we have a tool
-called [cargo-bisect-rustc]. It will automatically download and test
-various builds of rustc. For recent regressions, it is even able to
-use the builds from our CI to track down the regression to a specific
-PR; for older regressions, it will simply identify a nightly.
-
-To learn to use [cargo-bisect-rustc], check out [this blog post][learn], which
-gives a quick introduction to how it works. Additionally, there is a [Guide]
-which goes into more detail on how to use it. You can also ask questions at
-the Zulip stream [`#t-compiler/cargo-bisect-rustc`][zcbr], or help in
-improving the tool.
-
-[cargo-bisect-rustc]: https://github.com/rust-lang/cargo-bisect-rustc/
-[learn]: https://blog.rust-lang.org/inside-rust/2019/12/18/bisecting-rust-compiler.html
-[zcbr]: https://rust-lang.zulipchat.com/#narrow/stream/217417-t-compiler.2Fcargo-bisect-rustc
-[Guide]: https://rust-lang.github.io/cargo-bisect-rustc/
diff --git a/src/doc/rustc-dev-guide/src/notification-groups/llvm.md b/src/doc/rustc-dev-guide/src/notification-groups/llvm.md
deleted file mode 100644
index 9d008728543..00000000000
--- a/src/doc/rustc-dev-guide/src/notification-groups/llvm.md
+++ /dev/null
@@ -1,38 +0,0 @@
-# LLVM Icebreakers Notification group
-
-**Github Label:** [A-LLVM] <br>
-**Ping command:** `@rustbot ping icebreakers-llvm`
-
-[A-LLVM]: https://github.com/rust-lang/rust/labels/A-LLVM
-
-*Note*: this notification group is *not* the same as the LLVM working group
-(WG-llvm).
-
-The "LLVM Icebreakers Notification Group" are focused on bugs that center around
-LLVM. These bugs often arise because of LLVM optimizations gone awry, or as the
-result of an LLVM upgrade. The goal here is:
-
-- to determine whether the bug is a result of us generating invalid LLVM IR,
-  or LLVM misoptimizing;
-- if the former, to fix our IR;
-- if the latter, to try and file a bug on LLVM (or identify an existing bug).
-
-The group may also be asked to weigh in on other sorts of LLVM-focused
-questions.
-
-## Helpful tips and options
-
-The ["Debugging LLVM"][d] section of the
-rustc-dev-guide gives a step-by-step process for how to help debug bugs
-caused by LLVM. In particular, it discusses how to emit LLVM IR, run
-the LLVM IR optimization pipelines, and so forth. You may also find
-it useful to look at the various codegen options listed under `-C help`
-and the internal options under `-Z help` -- there are a number that
-pertain to LLVM (just search for LLVM).
-
-[d]: ../backend/debugging.md
-
-## If you do narrow to an LLVM bug
-
-The ["Debugging LLVM"][d] section also describes what to do once
-you've identified the bug.
diff --git a/src/doc/rustc-dev-guide/src/rustdoc-internals.md b/src/doc/rustc-dev-guide/src/rustdoc-internals.md
index bc91c62d873..0234d4a920e 100644
--- a/src/doc/rustc-dev-guide/src/rustdoc-internals.md
+++ b/src/doc/rustc-dev-guide/src/rustdoc-internals.md
@@ -270,35 +270,6 @@ in `test.rs` is the function `make_test`, which is where hand-written
 Some extra reading about `make_test` can be found
 [here](https://quietmisdreavus.net/code/2018/02/23/how-the-doctests-get-made/).
 
-## Dotting i's And Crossing t's
-
-So that's `rustdoc`'s code in a nutshell, but there's more things in the
-compiler that deal with it. Since we have the full `compiletest` suite at hand,
-there's a set of tests in `tests/rustdoc` that make sure the final `HTML` is
-what we expect in various situations. These tests also use a supplementary
-script, `src/etc/htmldocck.py`, that allows it to look through the final `HTML`
-using `XPath` notation to get a precise look at the output. The full
-description of all the commands available to `rustdoc` tests (e.g. [`@has`] and
-[`@matches`]) is in [`htmldocck.py`].
-
-To use multiple crates in a `rustdoc` test, add `//@ aux-build:filename.rs`
-to the top of the test file. `filename.rs` should be placed in an `auxiliary`
-directory relative to the test file with the comment. If you need to build
-docs for the auxiliary file, use `//@ build-aux-docs`.
-
-In addition, there are separate tests for the search index and `rustdoc`'s
-ability to query it. The files in `tests/rustdoc-js` each contain a
-different search query and the expected results, broken out by search tab.
-These files are processed by a script in `src/tools/rustdoc-js` and the `Node.js`
-runtime. These tests don't have as thorough of a writeup, but a broad example
-that features results in all tabs can be found in `basic.js`. The basic idea is
-that you match a given `QUERY` with a set of `EXPECTED` results, complete with
-the full item path of each item.
-
-[`@has`]: https://github.com/rust-lang/rust/blob/master/src/etc/htmldocck.py#L39
-[`@matches`]: https://github.com/rust-lang/rust/blob/master/src/etc/htmldocck.py#L44
-[`htmldocck.py`]: https://github.com/rust-lang/rust/blob/master/src/etc/htmldocck.py
-
 ## Testing Locally
 
 Some features of the generated `HTML` documentation might require local
diff --git a/src/doc/rustc-dev-guide/src/rustdoc-internals/rustdoc-gui-test-suite.md b/src/doc/rustc-dev-guide/src/rustdoc-internals/rustdoc-gui-test-suite.md
new file mode 100644
index 00000000000..e155f960e3d
--- /dev/null
+++ b/src/doc/rustc-dev-guide/src/rustdoc-internals/rustdoc-gui-test-suite.md
@@ -0,0 +1,14 @@
+# The `rustdoc-gui` test suite
+
+> **FIXME**: This section is a stub. Please help us flesh it out!
+
+This page is about the test suite named `rustdoc-gui` used to test the "GUI" of `rustdoc` (i.e., the HTML/JS/CSS as rendered in a browser).
+For other rustdoc-specific test suites, see [Rustdoc test suites].
+
+These use a NodeJS-based tool called [`browser-UI-test`] that uses [puppeteer] to run tests in a headless browser and check rendering and interactivity. For information on how to write this form of test, see [`tests/rustdoc-gui/README.md`][rustdoc-gui-readme] as well as [the description of the `.goml` format][goml-script]
+
+[Rustdoc test suites]: ../tests/compiletest.md#rustdoc-test-suites
+[`browser-UI-test`]: https://github.com/GuillaumeGomez/browser-UI-test/
+[puppeteer]: https://pptr.dev/
+[rustdoc-gui-readme]: https://github.com/rust-lang/rust/blob/master/tests/rustdoc-gui/README.md
+[goml-script]: https://github.com/GuillaumeGomez/browser-UI-test/blob/master/goml-script.md
diff --git a/src/doc/rustc-dev-guide/src/rustdoc-internals/rustdoc-json-test-suite.md b/src/doc/rustc-dev-guide/src/rustdoc-internals/rustdoc-json-test-suite.md
new file mode 100644
index 00000000000..e08f7709506
--- /dev/null
+++ b/src/doc/rustc-dev-guide/src/rustdoc-internals/rustdoc-json-test-suite.md
@@ -0,0 +1,3 @@
+# The `rustdoc-json` test suite
+
+> **FIXME**: This section is a stub. It will be populated by [PR #2422](https://github.com/rust-lang/rustc-dev-guide/pull/2422/).
diff --git a/src/doc/rustc-dev-guide/src/rustdoc-internals/rustdoc-test-suite.md b/src/doc/rustc-dev-guide/src/rustdoc-internals/rustdoc-test-suite.md
index bad7ac19da2..b05318ce9e6 100644
--- a/src/doc/rustc-dev-guide/src/rustdoc-internals/rustdoc-test-suite.md
+++ b/src/doc/rustc-dev-guide/src/rustdoc-internals/rustdoc-test-suite.md
@@ -1,112 +1,191 @@
 # The `rustdoc` test suite
 
-This page is specifically about the test suite named `rustdoc`.
-For other test suites used for testing rustdoc, see [Rustdoc tests](../rustdoc.md#tests).
+This page is about the test suite named `rustdoc` used to test the HTML output of `rustdoc`.
+For other rustdoc-specific test suites, see [Rustdoc test suites].
 
-The `rustdoc` test suite is specifically used to test the HTML output of rustdoc.
+Each test file in this test suite is simply a Rust source file `file.rs` sprinkled with
+so-called *directives* located inside normal Rust code comments.
+These come in two flavors: *Compiletest* and *HtmlDocCk*.
 
-This is achieved by means of `htmldocck.py`, a custom checker script that leverages [XPath].
+To learn more about the former, read [Compiletest directives].
+For the latter, continue reading.
 
-[XPath]: https://en.wikipedia.org/wiki/XPath
+Internally, [`compiletest`] invokes the supplementary checker script [`htmldocck.py`].
 
-## Directives
-Directives to htmldocck are similar to those given to `compiletest` in that they take the form of `//@` comments.
+[Rustdoc test suites]: ../tests/compiletest.md#rustdoc-test-suites
+[`compiletest`]: ../tests/compiletest.md
+[`htmldocck.py`]: https://github.com/rust-lang/rust/blob/master/src/etc/htmldocck.py
 
-In addition to the directives listed here,
-`rustdoc` tests also support most
-[compiletest directives](../tests/directives.html).
+## HtmlDocCk Directives
 
-All `PATH`s in directives are relative to the rustdoc output directory (`build/TARGET/test/rustdoc/TESTNAME`),
-so it is conventional to use a `#![crate_name = "foo"]` attribute to avoid
-having to write a long crate name multiple times.
-To avoid repetition, `-` can be used in any `PATH` argument to re-use the previous `PATH` argument.
+Directives to HtmlDocCk are assertions that place constraints on the generated HTML.
+They look similar to those given to `compiletest` in that they take the form of `//@` comments
+but ultimately, they are completey distinct and processed by different programs.
 
-All arguments take the form of quoted strings
-(both single and double quotes are supported),
-with the exception of `COUNT` and the special `-` form of `PATH`.
+[XPath] is used to query parts of the HTML document tree.
+
+**Introductory example**:
+
+```rust,ignore (illustrative)
+//@ has file/type.Alias.html
+//@ has - '//*[@class="rust item-decl"]//code' 'type Alias = Option<i32>;'
+pub type Alias = Option<i32>;
+```
+
+Here, we check that documentation generated for crate `file` contains a page for the
+public type alias `Alias` where the code block that is found at the top contains the
+expected rendering of the item. The `//*[@class="rust item-decl"]//code` is an XPath
+expression.
 
-Directives are assertions that place constraints on the generated HTML.
+Conventionally, you place these directives directly above the thing they are meant to test.
+Technically speaking however, they don't need to be as HtmlDocCk only looks for the directives.
 
-All directives (except `files`) can be negated by putting a `!` in front of their name.
+All directives take a `PATH` argument.
+To avoid repetition, `-` can be passed to it to re-use the previous `PATH` argument.
+Since the path contains the name of the crate, it is conventional to add a
+`#![crate_name = "foo"]` attribute to the crate root to shorten the resulting path.
+
+All arguments take the form of shell-style (single or double) quoted strings,
+with the exception of `COUNT` and the special `-` form of `PATH`.
+
+All directives (except `files`) can be *negated* by putting a `!` in front of their name.
+Before you add negated directives, please read about [their caveats](#caveats).
 
 Similar to shell commands,
 directives can extend across multiple lines if their last char is `\`.
 In this case, the start of the next line should be `//`, with no `@`.
 
-For example, `//@ !has 'foo/struct.Bar.html'` checks that crate `foo` does not have a page for a struct named `Bar` in the crate root.
+Use the special string `{{channel}}` in XPaths, `PATTERN` arguments and [snapshot files](#snapshot)
+if you'd like to refer to the URL `https://doc.rust-lang.org/CHANNEL` where `CHANNEL` refers to the
+current release channel (e.g, `stable` or `nightly`).
+
+Listed below are all possible directives:
+
+[XPath]: https://en.wikipedia.org/wiki/XPath
 
 ### `has`
 
-Usage 1: `//@ has PATH`
-Usage 2: `//@ has PATH XPATH PATTERN`
+> Usage 1: `//@ has PATH`
 
-In the first form, `has` checks that a given file exists.
+Check that the file given by `PATH` exists.
 
-In the second form, `has` is an alias for `matches`,
-except `PATTERN` is a whitespace-normalized[^1] string instead of a regex.
+> Usage 2: `//@ has PATH XPATH PATTERN`
 
-### `matches`
+Checks that the text of each element / attribute / text selected by `XPATH` in the
+whitespace-normalized[^1] file given by `PATH` matches the
+(also whitespace-normalized) string `PATTERN`.
+
+**Tip**: If you'd like to avoid whitespace normalization and/or if you'd like to match with a regex,
+use `matches` instead.
 
-Usage: `//@ matches PATH XPATH PATTERN`
+### `hasraw`
 
-Checks that the text of each element selected by `XPATH` in `PATH` matches the python-flavored regex `PATTERN`.
+> Usage: `//@ hasraw PATH PATTERN`
 
-### `matchesraw`
+Checks that the contents of the whitespace-normalized[^1] file given by `PATH`
+matches the (also whitespace-normalized) string `PATTERN`.
 
-Usage: `//@ matchesraw PATH PATTERN`
+**Tip**: If you'd like to avoid whitespace normalization and / or if you'd like to match with a
+regex, use `matchesraw` instead.
 
-Checks that the contents of the file `PATH` matches the regex `PATTERN`.
+### `matches`
 
-### `hasraw`
+> Usage: `//@ matches PATH XPATH PATTERN`
 
-Usage: `//@ hasraw PATH PATTERN`
+Checks that the text of each element / attribute / text selected by `XPATH` in the
+file given by `PATH` matches the Python-flavored[^2] regex `PATTERN`.
 
-Same as `matchesraw`, except `PATTERN` is a whitespace-normalized[^1] string instead of a regex.
+### `matchesraw`
+
+> Usage: `//@ matchesraw PATH PATTERN`
+
+Checks that the contents of the file given by `PATH` matches the
+Python-flavored[^2] regex `PATTERN`.
 
 ### `count`
 
-Usage: `//@ count PATH XPATH COUNT`
+> Usage: `//@ count PATH XPATH COUNT`
 
-Checks that there are exactly `COUNT` matches for `XPATH` within the file `PATH`.
+Checks that there are exactly `COUNT` matches for `XPATH` within the file given by `PATH`.
 
 ### `snapshot`
 
-Usage: `//@ snapshot NAME PATH XPATH`
+> Usage: `//@ snapshot NAME PATH XPATH`
 
-Creates a snapshot test named NAME.
-A snapshot test captures a subtree of the DOM, at the location
-determined by the XPath, and compares it to a pre-recorded value
-in a file. The file's name is the test's name with the `.rs` extension
-replaced with `.NAME.html`, where NAME is the snapshot's name.
+Checks that the element / text selected by `XPATH` in the file given by `PATH` matches the
+pre-recorded subtree or text (the "snapshot") in file `FILE_STEM.NAME.html` where `FILE_STEM`
+is the file stem of the test file.
 
-htmldocck supports the `--bless` option to accept the current subtree
-as expected, saving it to the file determined by the snapshot's name.
-compiletest's `--bless` flag is forwarded to htmldocck.
+Pass the `--bless` option to `compiletest` to accept the current subtree/text as expected.
+This will overwrite the aforementioned file (or create it if it doesn't exist). It will
+automatically normalize the channel-dependent URL `https://doc.rust-lang.org/CHANNEL` to
+the special string `{{channel}}`.
 
 ### `has-dir`
 
-Usage: `//@ has-dir PATH`
+> Usage: `//@ has-dir PATH`
 
-Checks for the existence of directory `PATH`.
+Checks for the existence of the directory given by `PATH`.
 
 ### `files`
 
-Usage: `//@ files PATH ENTRIES`
+> Usage: `//@ files PATH ENTRIES`
+
+Checks that the directory given by `PATH` contains exactly `ENTRIES`.
+`ENTRIES` is a Python-like list of strings inside a quoted string.
+
+**Example**: `//@ files "foo/bar" '["index.html", "sidebar-items.js"]'`
+
+[^1]: Whitespace normalization means that all spans of consecutive whitespace are replaced with a single space.
+[^2]: They are Unicode aware (flag `UNICODE` is set), match case-sensitively and in single-line mode.
+
+## Compiletest Directives (Brief)
+
+As mentioned in the introduction, you also have access to [compiletest directives].
+Most importantly, they allow you to register auxiliary crates and
+to pass flags to the `rustdoc` binary under test.
+It's *strongly recommended* to read that chapter if you don't know anything about them yet.
+
+Here are some details that are relevant to this test suite specifically:
 
-Checks that the directory `PATH` contains exactly `ENTRIES`.
-`ENTRIES` is a python list of strings inside a quoted string,
-as if it were to be parsed by `eval`.
-(note that the list is actually parsed by `shlex.split`,
-so it cannot contain arbitrary python expressions).
+* While you can use both `//@ compile-flags` and `//@ doc-flags` to pass flags to `rustdoc`,
+  prefer to user the latter to show intent. The former is meant for `rustc`.
+* Add `//@ build-aux-docs` to the test file that has auxiliary crates to not only compile the
+  auxiliaries with `rustc` but to also document them with `rustdoc`.
 
-Example: `//@ files "foo/bar" '["index.html", "sidebar-items.js"]'`
+## Caveats
 
-[^1]: Whitespace normalization means that all spans of consecutive whitespace are replaced with a single space.  The files themselves are also whitespace-normalized.
+Testing for the absence of an element or a piece of text is quite fragile and not very future proof.
+
+It's not unusual that the *shape* of the generated HTML document tree changes from time to time.
+This includes for example renamings of CSS classes.
+
+Whenever that happens, *positive* checks will either continue to match the intended element /
+attribute / text (if their XPath expression is general / loose enough) and
+thus continue to test the correct thing or they won't in which case they would fail thereby
+forcing the author of the change to look at them.
+
+Compare that to *negative* checks (e.g., `//@ !has PATH XPATH PATTERN`) which won't fail if their
+XPath expression "no longer" matches. The author who changed "the shape" thus won't get notified and
+as a result someone else can unintentionally reintroduce `PATTERN` into the generated docs without
+the original negative check failing.
+
+**Note**: Please avoid the use of *negated* checks!
+
+**Tip**: If you can't avoid it, please **always** pair it with an analogous positive check in the
+immediate vicinity, so people changing "the shape" have a chance to notice and to update the
+negated check!
 
 ## Limitations
-`htmldocck.py` uses the xpath implementation from the standard library.
+
+HtmlDocCk uses the XPath implementation from the Python standard library.
 This leads to several limitations:
+
 * All `XPATH` arguments must start with `//` due to a flaw in the implementation.
 * Many XPath features (functions, axies, etc.) are not supported.
 * Only well-formed HTML can be parsed (hopefully rustdoc doesn't output mismatched tags).
 
+Furthmore, compiletest [revisions] are not supported.
+
+[revisions]: ../tests/compiletest.md#revisions
+[compiletest directives]: ../tests/directives.md
diff --git a/src/doc/rustc-dev-guide/src/rustdoc.md b/src/doc/rustc-dev-guide/src/rustdoc.md
index de70ba63823..52ae48c3735 100644
--- a/src/doc/rustc-dev-guide/src/rustdoc.md
+++ b/src/doc/rustc-dev-guide/src/rustdoc.md
@@ -67,43 +67,29 @@ does is call the `main()` that's in this crate's `lib.rs`, though.)
 
 ## Code structure
 
-* All paths in this section are relative to `src/librustdoc` in the rust-lang/rust repository.
+All paths in this section are relative to `src/librustdoc/` in the rust-lang/rust repository.
+
 * Most of the HTML printing code is in `html/format.rs` and `html/render/mod.rs`.
-  It's in a bunch of `fmt::Display` implementations and supplementary
-  functions.
-* The types that got `Display` impls above are defined in `clean/mod.rs`, right
-  next to the custom `Clean` trait used to process them out of the rustc HIR.
+  It's in a bunch of functions returning `impl std::fmt::Display`.
+* The data types that get rendered by the functions mentioned above are defined in `clean/types.rs`.
+  The functions responsible for creating them from the `HIR` and the `rustc_middle::ty` IR
+  live in `clean/mod.rs`.
 * The bits specific to using rustdoc as a test harness are in
   `doctest.rs`.
 * The Markdown renderer is loaded up in `html/markdown.rs`, including functions
   for extracting doctests from a given block of Markdown.
 * Frontend CSS and JavaScript are stored in `html/static/`.
+  * Re. JavaScript, type annotations are written using [TypeScript-flavored JSDoc]
+comments and an external `.d.ts` file.
+    This way, the code itself remains plain, valid JavaScript.
+    We only use `tsc` as a linter.
 
-## Tests
+[TypeScript-flavored JSDoc]: https://www.typescriptlang.org/docs/handbook/jsdoc-supported-types.html
 
-* Tests on search engine and index are located in `tests/rustdoc-js` and `tests/rustdoc-js-std`.
-  The format is specified
-  [in the search guide](rustdoc-internals/search.md#testing-the-search-engine).
-* Tests on the "UI" of rustdoc (the terminal output it produces when run) are in
-  `tests/rustdoc-ui`
-* Tests on the "GUI" of rustdoc (the HTML, JS, and CSS as rendered in a browser)
-  are in `tests/rustdoc-gui`. These use a [NodeJS tool called
-  browser-UI-test](https://github.com/GuillaumeGomez/browser-UI-test/) that uses
-  puppeteer to run tests in a headless browser and check rendering and
-  interactivity.  For information on how to write this form of test,
-  see [`tests/rustdoc-gui/README.md`][rustdoc-gui-readme]
-  as well as [the description of the `.goml` format][goml-script]
-* Tests on the structure of rustdoc HTML output are located in `tests/rustdoc`,
-  where they're handled by the test runner of bootstrap and
-  the supplementary script `src/etc/htmldocck.py`.
-  [These tests have several extra directives available to them](./rustdoc-internals/rustdoc-test-suite.md).
-* Additionally, JavaScript type annotations are written using [TypeScript-flavored JSDoc]
-  comments and an external d.ts file. The code itself is plain, valid JavaScript; we only
-  use tsc as a linter.
+## Tests
 
-[TypeScript-flavored JSDoc]: https://www.typescriptlang.org/docs/handbook/jsdoc-supported-types.html
-[rustdoc-gui-readme]: https://github.com/rust-lang/rust/blob/master/tests/rustdoc-gui/README.md
-[goml-script]: https://github.com/GuillaumeGomez/browser-UI-test/blob/master/goml-script.md
+`rustdoc`'s integration tests are split across several test suites.
+See [Rustdoc tests suites](tests/compiletest.md#rustdoc-test-suites) for more details.
 
 ## Constraints
 
diff --git a/src/doc/rustc-dev-guide/src/tests/compiletest.md b/src/doc/rustc-dev-guide/src/tests/compiletest.md
index ee06ca3b698..ded30234e70 100644
--- a/src/doc/rustc-dev-guide/src/tests/compiletest.md
+++ b/src/doc/rustc-dev-guide/src/tests/compiletest.md
@@ -56,6 +56,9 @@ incremental compilation. The various suites are defined in
 
 The following test suites are available, with links for more information:
 
+[`tests`]: https://github.com/rust-lang/rust/blob/master/tests
+[`src/tools/compiletest/src/common.rs`]: https://github.com/rust-lang/rust/tree/master/src/tools/compiletest/src/common.rs
+
 ### Compiler-specific test suites
 
 | Test suite                                | Purpose                                                                                                             |
@@ -71,6 +74,7 @@ The following test suites are available, with links for more information:
 | [`mir-opt`](#mir-opt-tests)               | Check MIR generation and optimizations                                                                              |
 | [`coverage`](#coverage-tests)             | Check coverage instrumentation                                                                                      |
 | [`coverage-run-rustdoc`](#coverage-tests) | `coverage` tests that also run instrumented doctests                                                                |
+| [`crashes`](#crashes-tests)               | Check that the compiler ICEs/panics/crashes on certain inputs to catch accidental fixes                             |
 
 ### General purpose test suite
 
@@ -78,19 +82,23 @@ The following test suites are available, with links for more information:
 
 ### Rustdoc test suites
 
-See [Rustdoc tests](../rustdoc.md#tests) for more details.
+| Test suite                           | Purpose                                                                  |
+|--------------------------------------|--------------------------------------------------------------------------|
+| [`rustdoc`][rustdoc-html-tests]      | Check HTML output of `rustdoc`                                           |
+| [`rustdoc-gui`][rustdoc-gui-tests]   | Check `rustdoc`'s GUI using a web browser                                |
+| [`rustdoc-js`][rustdoc-js-tests]     | Check `rustdoc`'s search engine and index                                |
+| [`rustdoc-js-std`][rustdoc-js-tests] | Check `rustdoc`'s search engine and index on the std library docs        |
+| [`rustdoc-json`][rustdoc-json-tests] | Check JSON output of `rustdoc`                                           |
+| `rustdoc-ui`                         | Check terminal output of `rustdoc` ([see also](ui.md))                   |
 
-| Test suite       | Purpose                                                                  |
-|------------------|--------------------------------------------------------------------------|
-| `rustdoc`        | Check `rustdoc` generated files contain the expected documentation       |
-| `rustdoc-gui`    | Check `rustdoc`'s GUI using a web browser                                |
-| `rustdoc-js`     | Check `rustdoc` search is working as expected                            |
-| `rustdoc-js-std` | Check rustdoc search is working as expected specifically on the std docs |
-| `rustdoc-json`   | Check JSON output of `rustdoc`                                           |
-| `rustdoc-ui`     | Check terminal output of `rustdoc`                                       |
+Some rustdoc-specific tests can also be found in `ui/rustdoc/`.
+These check rustdoc-related or -specific lints that (also) run as part of `rustc`, not (only) `rustdoc`.
+Run-make tests pertaining to rustdoc are typically named `run-make/rustdoc-*/`.
 
-[`tests`]: https://github.com/rust-lang/rust/blob/master/tests
-[`src/tools/compiletest/src/common.rs`]: https://github.com/rust-lang/rust/tree/master/src/tools/compiletest/src/common.rs
+[rustdoc-html-tests]: ../rustdoc-internals/rustdoc-test-suite.md
+[rustdoc-gui-tests]: ../rustdoc-internals/rustdoc-gui-test-suite.md
+[rustdoc-js-tests]: ../rustdoc-internals/search.md#testing-the-search-engine
+[rustdoc-json-tests]: ../rustdoc-internals/rustdoc-json-test-suite.md
 
 ### Pretty-printer tests
 
@@ -107,7 +115,7 @@ default behavior without any commands is to:
 2. Run `rustc -Zunpretty=normal` on the output of the previous step.
 3. The output of the previous two steps should be the same.
 4. Run `rustc -Zno-codegen` on the output to make sure that it can type check
-   (this is similar to running `cargo check`).
+   (similar to `cargo check`).
 
 If any of the commands above fail, then the test fails.
 
diff --git a/src/doc/rustc-dev-guide/src/tests/directives.md b/src/doc/rustc-dev-guide/src/tests/directives.md
index 2dff21ed61c..839076b809d 100644
--- a/src/doc/rustc-dev-guide/src/tests/directives.md
+++ b/src/doc/rustc-dev-guide/src/tests/directives.md
@@ -202,6 +202,7 @@ settings:
   `//@ needs-crate-type: cdylib, proc-macro` will cause the test to be ignored
   on `wasm32-unknown-unknown` target because the target does not support the
   `proc-macro` crate type.
+- `needs-target-std` — ignores if target platform does not have std support.
 
 The following directives will check LLVM support:
 
@@ -261,7 +262,7 @@ Consider writing the test as a proper incremental test instead.
 
 | Directive   | Explanation                                                  | Supported test suites                    | Possible values           |
 |-------------|--------------------------------------------------------------|------------------------------------------|---------------------------|
-| `doc-flags` | Flags passed to `rustdoc` when building the test or aux file | `rustdoc`, `rustdoc-js`, `rustdoc-json` | Any valid `rustdoc` flags |
+| `doc-flags` | Flags passed to `rustdoc` when building the test or aux file | `rustdoc`, `rustdoc-js`, `rustdoc-json`  | Any valid `rustdoc` flags |
 
 <!--
 **FIXME(rustdoc)**: what does `check-test-line-numbers-match` do?
@@ -269,6 +270,17 @@ Asked in
 <https://rust-lang.zulipchat.com/#narrow/stream/266220-t-rustdoc/topic/What.20is.20the.20.60check-test-line-numbers-match.60.20directive.3F>.
 -->
 
+#### Test-suite-specific directives
+
+The test suites [`rustdoc`][rustdoc-html-tests], [`rustdoc-js`/`rustdoc-js-std`][rustdoc-js-tests]
+and [`rustdoc-json`][rustdoc-json-tests] each feature an additional set of directives whose basic
+syntax resembles the one of compiletest directives but which are ultimately read and checked by
+separate tools. For more information, please read their respective chapters as linked above.
+
+[rustdoc-html-tests]: ../rustdoc-internals/rustdoc-test-suite.md
+[rustdoc-js-tests]: ../rustdoc-internals/search.html#testing-the-search-engine
+[rustdoc-json-tests]: ../rustdoc-internals/rustdoc-json-test-suite.md
+
 ### Pretty printing
 
 See [Pretty-printer](compiletest.md#pretty-printer-tests).
diff --git a/src/doc/rustc-dev-guide/src/tests/ui.md b/src/doc/rustc-dev-guide/src/tests/ui.md
index 3402838da87..25d3efdbb82 100644
--- a/src/doc/rustc-dev-guide/src/tests/ui.md
+++ b/src/doc/rustc-dev-guide/src/tests/ui.md
@@ -220,8 +220,12 @@ negligible (i.e. there is no semantic difference between `//~ ERROR` and
 `//~ERROR` although the former is more common in the codebase).
 
 `~? <diagnostic kind>` (example being `~? ERROR`)
-is used to match diagnostics without line information.
-These can be placed on any line in the test file, but are conventionally placed at the end.
+is used to match diagnostics _without_ line info at all,
+or where the line info is outside the main test file[^main test file].
+These annotations can be placed on any line in the test file.
+
+[^main test file]: This is a file that has the `~?` annotations,
+as distinct from aux files, or sources that we have no control over.
 
 ### Error annotation examples
 
diff --git a/src/doc/rustc-dev-guide/triagebot.toml b/src/doc/rustc-dev-guide/triagebot.toml
index 978802edf3f..b3f4c2d281c 100644
--- a/src/doc/rustc-dev-guide/triagebot.toml
+++ b/src/doc/rustc-dev-guide/triagebot.toml
@@ -72,6 +72,23 @@ days-threshold = 7
 # Documentation at: https://forge.rust-lang.org/triagebot/pr-assignment.html
 [assign]
 
+# NOTE: do not add `[assign.owners]` if we still wish to keep the opt-in
+# reviewer model, as `[assign.owners]` will cause triagebot auto-reviewer
+# assignment to kick in.
+
+# Custom PR welcome message for when no auto reviewer assignment is performed
+# and no explicit manual reviewer selection is made.
+# Documentation at: https://forge.rust-lang.org/triagebot/pr-assignment.html#custom-welcome-messages
+[assign.custom_welcome_messages]
+welcome-message = ""
+welcome-message-no-reviewer = """\
+Thanks for the PR. If you have write access, feel free to merge this PR if it \
+does not need reviews. You can request a review using `r? rustc-dev-guide` or \
+`r? <username>`.
+"""
+
+# Groups for `r? <group>`.
+# Documentation at: https://forge.rust-lang.org/triagebot/pr-assignment.html#usage
 # Keep members alphanumerically sorted.
 [assign.adhoc_groups]
 rustc-dev-guide = [
diff --git a/src/doc/rustc/src/SUMMARY.md b/src/doc/rustc/src/SUMMARY.md
index a3939e5a5c4..201a5503079 100644
--- a/src/doc/rustc/src/SUMMARY.md
+++ b/src/doc/rustc/src/SUMMARY.md
@@ -113,6 +113,7 @@
     - [\*-unknown-openbsd](platform-support/openbsd.md)
     - [\*-unknown-redox](platform-support/redox.md)
     - [\*-unknown-uefi](platform-support/unknown-uefi.md)
+    - [\*-unknown-windows-msvc](platform-support/windows-msvc.md)
     - [\*-uwp-windows-msvc](platform-support/uwp-windows-msvc.md)
     - [\*-wrs-vxworks](platform-support/vxworks.md)
     - [wasm32-wasip1](platform-support/wasm32-wasip1.md)
diff --git a/src/doc/rustc/src/platform-support.md b/src/doc/rustc/src/platform-support.md
index e2e2ad9ac3b..3cab57df75a 100644
--- a/src/doc/rustc/src/platform-support.md
+++ b/src/doc/rustc/src/platform-support.md
@@ -33,12 +33,12 @@ All tier 1 targets with host tools support the full standard library.
 target | notes
 -------|-------
 [`aarch64-apple-darwin`](platform-support/apple-darwin.md) | ARM64 macOS (11.0+, Big Sur+)
-`aarch64-unknown-linux-gnu` | ARM64 Linux (kernel 4.1, glibc 2.17+)
-`i686-pc-windows-msvc` | 32-bit MSVC (Windows 10+, Windows Server 2016+, Pentium 4) [^x86_32-floats-return-ABI] [^win32-msvc-alignment]
+`aarch64-unknown-linux-gnu` | ARM64 Linux (kernel 4.1+, glibc 2.17+)
+[`i686-pc-windows-msvc`](platform-support/windows-msvc.md) | 32-bit MSVC (Windows 10+, Windows Server 2016+, Pentium 4) [^x86_32-floats-return-ABI] [^win32-msvc-alignment]
 `i686-unknown-linux-gnu` | 32-bit Linux (kernel 3.2+, glibc 2.17+, Pentium 4) [^x86_32-floats-return-ABI]
 [`x86_64-apple-darwin`](platform-support/apple-darwin.md) | 64-bit macOS (10.12+, Sierra+)
 [`x86_64-pc-windows-gnu`](platform-support/windows-gnu.md) | 64-bit MinGW (Windows 10+, Windows Server 2016+)
-`x86_64-pc-windows-msvc` | 64-bit MSVC (Windows 10+, Windows Server 2016+)
+[`x86_64-pc-windows-msvc`](platform-support/windows-msvc.md) | 64-bit MSVC (Windows 10+, Windows Server 2016+)
 `x86_64-unknown-linux-gnu` | 64-bit Linux (kernel 3.2+, glibc 2.17+)
 
 [^x86_32-floats-return-ABI]: Due to limitations of the C ABI, floating-point support on `i686` targets is non-compliant: floating-point return values are passed via an x87 register, so NaN payload bits can be lost. Functions with the default Rust ABI are not affected. See [issue #115567][x86-32-float-return-issue].
@@ -88,23 +88,23 @@ so Rustup may install the documentation for a similar tier 1 target instead.
 
 target | notes
 -------|-------
-`aarch64-pc-windows-msvc` | ARM64 Windows MSVC
+[`aarch64-pc-windows-msvc`](platform-support/windows-msvc.md) | ARM64 Windows MSVC
 `aarch64-unknown-linux-musl` | ARM64 Linux with musl 1.2.3
 [`aarch64-unknown-linux-ohos`](platform-support/openharmony.md) | ARM64 OpenHarmony
-`arm-unknown-linux-gnueabi` | Armv6 Linux (kernel 3.2, glibc 2.17)
-`arm-unknown-linux-gnueabihf` | Armv6 Linux, hardfloat (kernel 3.2, glibc 2.17)
-`armv7-unknown-linux-gnueabihf` | Armv7-A Linux, hardfloat (kernel 3.2, glibc 2.17)
+`arm-unknown-linux-gnueabi` | Armv6 Linux (kernel 3.2+, glibc 2.17)
+`arm-unknown-linux-gnueabihf` | Armv6 Linux, hardfloat (kernel 3.2+, glibc 2.17)
+`armv7-unknown-linux-gnueabihf` | Armv7-A Linux, hardfloat (kernel 3.2+, glibc 2.17)
 [`armv7-unknown-linux-ohos`](platform-support/openharmony.md) | Armv7-A OpenHarmony
-[`loongarch64-unknown-linux-gnu`](platform-support/loongarch-linux.md) | LoongArch64 Linux, LP64D ABI (kernel 5.19, glibc 2.36)
-[`loongarch64-unknown-linux-musl`](platform-support/loongarch-linux.md) | LoongArch64 Linux, LP64D ABI (kernel 5.19, musl 1.2.5)
+[`loongarch64-unknown-linux-gnu`](platform-support/loongarch-linux.md) | LoongArch64 Linux, LP64D ABI (kernel 5.19+, glibc 2.36)
+[`loongarch64-unknown-linux-musl`](platform-support/loongarch-linux.md) | LoongArch64 Linux, LP64D ABI (kernel 5.19+, musl 1.2.5)
 [`i686-pc-windows-gnu`](platform-support/windows-gnu.md) | 32-bit MinGW (Windows 10+, Windows Server 2016+, Pentium 4) [^x86_32-floats-return-ABI] [^win32-msvc-alignment]
-`powerpc-unknown-linux-gnu` | PowerPC Linux (kernel 3.2, glibc 2.17)
-`powerpc64-unknown-linux-gnu` | PPC64 Linux (kernel 3.2, glibc 2.17)
-[`powerpc64le-unknown-linux-gnu`](platform-support/powerpc64le-unknown-linux-gnu.md) | PPC64LE Linux (kernel 3.10, glibc 2.17)
-[`powerpc64le-unknown-linux-musl`](platform-support/powerpc64le-unknown-linux-musl.md) | PPC64LE Linux (kernel 4.19, musl 1.2.3)
-[`riscv64gc-unknown-linux-gnu`](platform-support/riscv64gc-unknown-linux-gnu.md) | RISC-V Linux (kernel 4.20, glibc 2.29)
-[`riscv64gc-unknown-linux-musl`](platform-support/riscv64gc-unknown-linux-musl.md) | RISC-V Linux (kernel 4.20, musl 1.2.3)
-[`s390x-unknown-linux-gnu`](platform-support/s390x-unknown-linux-gnu.md) | S390x Linux (kernel 3.2, glibc 2.17)
+`powerpc-unknown-linux-gnu` | PowerPC Linux (kernel 3.2+, glibc 2.17)
+`powerpc64-unknown-linux-gnu` | PPC64 Linux (kernel 3.2+, glibc 2.17)
+[`powerpc64le-unknown-linux-gnu`](platform-support/powerpc64le-unknown-linux-gnu.md) | PPC64LE Linux (kernel 3.10+, glibc 2.17)
+[`powerpc64le-unknown-linux-musl`](platform-support/powerpc64le-unknown-linux-musl.md) | PPC64LE Linux (kernel 4.19+, musl 1.2.3)
+[`riscv64gc-unknown-linux-gnu`](platform-support/riscv64gc-unknown-linux-gnu.md) | RISC-V Linux (kernel 4.20+, glibc 2.29)
+[`riscv64gc-unknown-linux-musl`](platform-support/riscv64gc-unknown-linux-musl.md) | RISC-V Linux (kernel 4.20+, musl 1.2.3)
+[`s390x-unknown-linux-gnu`](platform-support/s390x-unknown-linux-gnu.md) | S390x Linux (kernel 3.2+, glibc 2.17)
 [`x86_64-unknown-freebsd`](platform-support/freebsd.md) | 64-bit x86 FreeBSD
 [`x86_64-unknown-illumos`](platform-support/illumos.md) | illumos
 `x86_64-unknown-linux-musl` | 64-bit Linux with musl 1.2.3
@@ -158,16 +158,16 @@ target | std | notes
 [`arm64ec-pc-windows-msvc`](platform-support/arm64ec-pc-windows-msvc.md) | ✓ | Arm64EC Windows MSVC
 [`armebv7r-none-eabi`](platform-support/armv7r-none-eabi.md) | * | Bare Armv7-R, Big Endian
 [`armebv7r-none-eabihf`](platform-support/armv7r-none-eabi.md) | * | Bare Armv7-R, Big Endian, hardfloat
-[`armv5te-unknown-linux-gnueabi`](platform-support/armv5te-unknown-linux-gnueabi.md) | ✓ | Armv5TE Linux (kernel 4.4, glibc 2.23)
+[`armv5te-unknown-linux-gnueabi`](platform-support/armv5te-unknown-linux-gnueabi.md) | ✓ | Armv5TE Linux (kernel 4.4+, glibc 2.23)
 `armv5te-unknown-linux-musleabi` | ✓ | Armv5TE Linux with musl 1.2.3
 [`armv7-linux-androideabi`](platform-support/android.md) | ✓ | Armv7-A Android
-`armv7-unknown-linux-gnueabi` | ✓ | Armv7-A Linux (kernel 4.15, glibc 2.27)
+`armv7-unknown-linux-gnueabi` | ✓ | Armv7-A Linux (kernel 4.15+, glibc 2.27)
 `armv7-unknown-linux-musleabi` | ✓ | Armv7-A Linux with musl 1.2.3
 `armv7-unknown-linux-musleabihf` | ✓ | Armv7-A Linux with musl 1.2.3, hardfloat
 [`armv7a-none-eabi`](platform-support/arm-none-eabi.md) | * | Bare Armv7-A
 [`armv7r-none-eabi`](platform-support/armv7r-none-eabi.md) | * | Bare Armv7-R
 [`armv7r-none-eabihf`](platform-support/armv7r-none-eabi.md) | * | Bare Armv7-R, hardfloat
-`i586-unknown-linux-gnu` | ✓ | 32-bit Linux (kernel 3.2, glibc 2.17, original Pentium) [^x86_32-floats-x87]
+`i586-unknown-linux-gnu` | ✓ | 32-bit Linux (kernel 3.2+, glibc 2.17, original Pentium) [^x86_32-floats-x87]
 `i586-unknown-linux-musl` | ✓ | 32-bit Linux (musl 1.2.3, original Pentium) [^x86_32-floats-x87]
 [`i686-linux-android`](platform-support/android.md) | ✓ | 32-bit x86 Android ([Pentium 4 plus various extensions](https://developer.android.com/ndk/guides/abis.html#x86)) [^x86_32-floats-return-ABI]
 [`i686-pc-windows-gnullvm`](platform-support/windows-gnullvm.md) | ✓ | 32-bit x86 MinGW (Windows 10+, Pentium 4), LLVM ABI [^x86_32-floats-return-ABI]
@@ -184,13 +184,13 @@ target | std | notes
 [`riscv32imc-unknown-none-elf`](platform-support/riscv32-unknown-none-elf.md) | * | Bare RISC-V (RV32IMC ISA)
 `riscv64gc-unknown-none-elf` | * | Bare RISC-V (RV64IMAFDC ISA)
 `riscv64imac-unknown-none-elf` | * | Bare RISC-V (RV64IMAC ISA)
-`sparc64-unknown-linux-gnu` | ✓ | SPARC Linux (kernel 4.4, glibc 2.23)
+`sparc64-unknown-linux-gnu` | ✓ | SPARC Linux (kernel 4.4+, glibc 2.23)
 [`thumbv6m-none-eabi`](platform-support/thumbv6m-none-eabi.md) | * | Bare Armv6-M
 [`thumbv7em-none-eabi`](platform-support/thumbv7em-none-eabi.md) | * | Bare Armv7E-M
 [`thumbv7em-none-eabihf`](platform-support/thumbv7em-none-eabi.md) | * | Bare Armv7E-M, hardfloat
 [`thumbv7m-none-eabi`](platform-support/thumbv7m-none-eabi.md) | * | Bare Armv7-M
 [`thumbv7neon-linux-androideabi`](platform-support/android.md) | ✓ | Thumb2-mode Armv7-A Android with NEON
-`thumbv7neon-unknown-linux-gnueabihf` | ✓ | Thumb2-mode Armv7-A Linux with NEON (kernel 4.4, glibc 2.23)
+`thumbv7neon-unknown-linux-gnueabihf` | ✓ | Thumb2-mode Armv7-A Linux with NEON (kernel 4.4+, glibc 2.23)
 [`thumbv8m.base-none-eabi`](platform-support/thumbv8m.base-none-eabi.md) | * | Bare Armv8-M Baseline
 [`thumbv8m.main-none-eabi`](platform-support/thumbv8m.main-none-eabi.md) | * | Bare Armv8-M Mainline
 [`thumbv8m.main-none-eabihf`](platform-support/thumbv8m.main-none-eabi.md) | * | Bare Armv8-M Mainline, hardfloat
@@ -206,7 +206,7 @@ target | std | notes
 [`x86_64-linux-android`](platform-support/android.md) | ✓ | 64-bit x86 Android
 [`x86_64-pc-windows-gnullvm`](platform-support/windows-gnullvm.md) | ✓ | 64-bit x86 MinGW (Windows 10+), LLVM ABI
 [`x86_64-unknown-fuchsia`](platform-support/fuchsia.md) | ✓ | 64-bit x86 Fuchsia
-`x86_64-unknown-linux-gnux32` | ✓ | 64-bit Linux (x32 ABI) (kernel 4.15, glibc 2.27)
+`x86_64-unknown-linux-gnux32` | ✓ | 64-bit Linux (x32 ABI) (kernel 4.15+, glibc 2.27)
 [`x86_64-unknown-none`](platform-support/x86_64-unknown-none.md) | * | Freestanding/bare-metal x86_64, softfloat
 [`x86_64-unknown-redox`](platform-support/redox.md) | ✓ | Redox OS
 [`x86_64-unknown-uefi`](platform-support/unknown-uefi.md) | ? | 64-bit UEFI
diff --git a/src/doc/rustc/src/platform-support/loongarch-none.md b/src/doc/rustc/src/platform-support/loongarch-none.md
index fd90b0a2763..7c3a7e6c8bc 100644
--- a/src/doc/rustc/src/platform-support/loongarch-none.md
+++ b/src/doc/rustc/src/platform-support/loongarch-none.md
@@ -11,8 +11,8 @@ Freestanding/bare-metal LoongArch binaries in ELF format: firmware, kernels, etc
 
 ## Target maintainers
 
-- [@heiher](https://github.com/heiher)
-- [@xen0n](https://github.com/xen0n)
+[@heiher](https://github.com/heiher)
+[@xen0n](https://github.com/xen0n)
 
 ## Requirements
 
diff --git a/src/doc/rustc/src/platform-support/wasm32-unknown-unknown.md b/src/doc/rustc/src/platform-support/wasm32-unknown-unknown.md
index b67f49c3a38..1e74c47221c 100644
--- a/src/doc/rustc/src/platform-support/wasm32-unknown-unknown.md
+++ b/src/doc/rustc/src/platform-support/wasm32-unknown-unknown.md
@@ -207,120 +207,3 @@ conditionally compile code instead. This is notably different to the way native
 platforms such as x86\_64 work, and this is due to the fact that WebAssembly
 binaries must only contain code the engine understands. Native binaries work so
 long as the CPU doesn't execute unknown code dynamically at runtime.
-
-## Broken `extern "C"` ABI
-
-This target has what is considered a broken `extern "C"` ABI implementation at
-this time. Notably the same signature in Rust and C will compile to different
-WebAssembly functions and be incompatible. This is considered a bug and it will
-be fixed in a future version of Rust.
-
-For example this Rust code:
-
-```rust,ignore (does-not-link)
-#[repr(C)]
-struct MyPair {
-    a: u32,
-    b: u32,
-}
-
-extern "C" {
-    fn take_my_pair(pair: MyPair) -> u32;
-}
-
-#[no_mangle]
-pub unsafe extern "C" fn call_c() -> u32 {
-    take_my_pair(MyPair { a: 1, b: 2 })
-}
-```
-
-compiles to a WebAssembly module that looks like:
-
-```wasm
-(module
-  (import "env" "take_my_pair" (func $take_my_pair (param i32 i32) (result i32)))
-  (func $call_c
-    i32.const 1
-    i32.const 2
-    call $take_my_pair
-  )
-)
-```
-
-The function when defined in C, however, looks like
-
-```c
-struct my_pair {
-    unsigned a;
-    unsigned b;
-};
-
-unsigned take_my_pair(struct my_pair pair) {
-    return pair.a + pair.b;
-}
-```
-
-```wasm
-(module
-  (import "env" "__linear_memory" (memory 0))
-  (func $take_my_pair (param i32) (result i32)
-    local.get 0
-    i32.load offset=4
-    local.get 0
-    i32.load
-    i32.add
-  )
-)
-```
-
-Notice how Rust thinks `take_my_pair` takes two `i32` parameters but C thinks it
-only takes one.
-
-The correct definition of the `extern "C"` ABI for WebAssembly is located in the
-[WebAssembly/tool-conventions](https://github.com/WebAssembly/tool-conventions/blob/main/BasicCABI.md)
-repository. The `wasm32-unknown-unknown` target (and only this target, not other
-WebAssembly targets Rust support) does not correctly follow this document.
-
-Example issues in the Rust repository about this bug are:
-
-* [#115666](https://github.com/rust-lang/rust/issues/115666)
-* [#129486](https://github.com/rust-lang/rust/issues/129486)
-
-This current state of the `wasm32-unknown-unknown` backend is due to an
-unfortunate accident which got relied on. The `wasm-bindgen` project prior to
-0.2.89 was incompatible with the "correct" definition of `extern "C"` and it was
-seen as not worth the tradeoff of breaking `wasm-bindgen` historically to fix
-this issue in the compiler.
-
-Thanks to the heroic efforts of many involved in this, however, `wasm-bindgen`
-0.2.89 and later are compatible with the correct definition of `extern "C"` and
-the nightly compiler currently supports a `-Zwasm-c-abi` implemented in
-[#117919](https://github.com/rust-lang/rust/pull/117919). This nightly-only flag
-can be used to indicate whether the spec-defined version of `extern "C"` should
-be used instead of the "legacy" version of
-whatever-the-Rust-target-originally-implemented. For example using the above
-code you can see (lightly edited for clarity):
-
-```shell
-$ rustc +nightly -Zwasm-c-abi=spec foo.rs --target wasm32-unknown-unknown --crate-type lib --emit obj -O
-$ wasm-tools print foo.o
-(module
-  (import "env" "take_my_pair" (func $take_my_pair (param i32) (result i32)))
-  (func $call_c (result i32)
-    ;; ...
-  )
-  ;; ...
-)
-```
-
-which shows that the C and Rust definitions of the same function now agree like
-they should.
-
-The `-Zwasm-c-abi` compiler flag is tracked in
-[#122532](https://github.com/rust-lang/rust/issues/122532) and a lint was
-implemented in [#117918](https://github.com/rust-lang/rust/issues/117918) to
-help warn users about the transition if they're using `wasm-bindgen` 0.2.88 or
-prior. The current plan is to, in the future, switch `-Zwasm-c-api=spec` to
-being the default. Some time after that the `-Zwasm-c-abi` flag and the
-"legacy" implementation will all be removed. During this process users on a
-sufficiently updated version of `wasm-bindgen` should not experience breakage.
diff --git a/src/doc/rustc/src/platform-support/windows-msvc.md b/src/doc/rustc/src/platform-support/windows-msvc.md
new file mode 100644
index 00000000000..71dc4ddc2e6
--- /dev/null
+++ b/src/doc/rustc/src/platform-support/windows-msvc.md
@@ -0,0 +1,69 @@
+# `*-pc-windows-msvc`
+
+Windows MSVC targets.
+
+**Tier 1 with host tools:**
+
+- `i686-pc-windows-msvc`: Windows on 32-bit x86.
+- `x86_64-pc-windows-msvc`: Windows on 64-bit x86.
+
+**Tier 2 with host tools:**
+
+- `aarch64-pc-windows-msvc`: Windows on ARM64.
+
+## Target maintainers
+
+[@ChrisDenton](https://github.com/ChrisDenton)
+[@dpaoliello](https://github.com/dpaoliello)
+[@lambdageek](https://github.com/lambdageek)
+[@sivadeilra](https://github.com/sivadeilra)
+[@wesleywiser](https://github.com/wesleywiser)
+
+## Requirements
+
+### OS version
+
+Windows 10 or higher is required for client installs, Windows Server 2016 or higher is required for server installs.
+
+### Host tooling
+
+The minimum supported Visual Studio version is 2017 but this support is not actively tested in CI.
+It is **highly** recommended to use the latest version of VS (currently VS 2022).
+
+### Platform details
+
+These targets fully implement the Rust standard library.
+
+The `extern "C"` calling convention conforms to Microsoft's default calling convention for the given architecture: [`__cdecl`] on `i686`, [`x64`] on `x86_64` and [`ARM64`] on `aarch64`.
+
+The `*-windows-msvc` targets produce PE/COFF binaries with CodeView debuginfo, the native formats used on Windows.
+
+[`__cdecl`]: https://learn.microsoft.com/en-us/cpp/cpp/cdecl?view=msvc-170
+[`x64`]: https://learn.microsoft.com/en-us/cpp/build/x64-calling-convention?view=msvc-170
+[`ARM64`]: https://learn.microsoft.com/en-us/cpp/build/arm64-windows-abi-conventions?view=msvc-170
+
+## Building Rust programs
+
+These targets are distributed via `rustup` and can be installed via `rustup component add [--toolchain {name}] {target}`.
+
+For example, adding the 32-bit x86 target to the `nightly` toolchain:
+
+```text
+rustup component add --toolchain nightly i686-pc-windows-msvc
+```
+
+or adding the ARM64 target to the active toolchain:
+
+```text
+rustup component add aarch64-pc-windows-msvc
+```
+
+## Testing
+
+There are no special requirements for testing and running this target.
+
+## Cross-compilation toolchains and C code
+
+Architectural cross-compilation from one Windows host to a different Windows platform is natively supported by the MSVC toolchain provided the appropriate components are selected when using the VS Installer.
+
+Cross-compilation from a non-Windows host to a `*-windows-msvc` target _may_ be possible but is not supported.
diff --git a/src/doc/rustdoc/src/unstable-features.md b/src/doc/rustdoc/src/unstable-features.md
index 69e5a5adbec..27910ad0ab7 100644
--- a/src/doc/rustdoc/src/unstable-features.md
+++ b/src/doc/rustdoc/src/unstable-features.md
@@ -581,7 +581,9 @@ For this rust code:
 
 ```rust
 /// ```
+/// #![allow(dead_code)]
 /// let x = 12;
+/// Ok(())
 /// ```
 pub trait Trait {}
 ```
@@ -590,10 +592,10 @@ The generated output (formatted) will look like this:
 
 ```json
 {
-  "format_version": 1,
+  "format_version": 2,
   "doctests": [
     {
-      "file": "foo.rs",
+      "file": "src/lib.rs",
       "line": 1,
       "doctest_attributes": {
         "original": "",
@@ -609,9 +611,17 @@ The generated output (formatted) will look like this:
         "added_css_classes": [],
         "unknown": []
       },
-      "original_code": "let x = 12;",
-      "doctest_code": "#![allow(unused)]\nfn main() {\nlet x = 12;\n}",
-      "name": "foo.rs - Trait (line 1)"
+      "original_code": "#![allow(dead_code)]\nlet x = 12;\nOk(())",
+      "doctest_code": {
+        "crate_level": "#![allow(unused)]\n#![allow(dead_code)]\n\n",
+        "code": "let x = 12;\nOk(())",
+        "wrapper": {
+          "before": "fn main() { fn _inner() -> core::result::Result<(), impl core::fmt::Debug> {\n",
+          "after": "\n} _inner().unwrap() }",
+          "returns_result": true
+        }
+      },
+      "name": "src/lib.rs - (line 1)"
     }
   ]
 }
@@ -624,6 +634,10 @@ The generated output (formatted) will look like this:
    * `doctest_attributes` contains computed information about the attributes used on the doctests. For more information about doctest attributes, take a look [here](write-documentation/documentation-tests.html#attributes).
    * `original_code` is the code as written in the source code before rustdoc modifies it.
    * `doctest_code` is the code modified by rustdoc that will be run. If there is a fatal syntax error, this field will not be present.
+     * `crate_level` is the crate level code (like attributes or `extern crate`) that will be added at the top-level of the generated doctest.
+     * `code` is "naked" doctest without anything from `crate_level` and `wrapper` content.
+     * `wrapper` contains extra code that will be added before and after `code`.
+       * `returns_result` is a boolean. If `true`, it means that the doctest returns a `Result` type.
    * `name` is the name generated by rustdoc which represents this doctest.
 
 ### html
diff --git a/src/doc/unstable-book/src/compiler-flags/macro-stats.md b/src/doc/unstable-book/src/compiler-flags/macro-stats.md
new file mode 100644
index 00000000000..b2622cff057
--- /dev/null
+++ b/src/doc/unstable-book/src/compiler-flags/macro-stats.md
@@ -0,0 +1,24 @@
+# `macro-stats`
+
+This feature is perma-unstable and has no tracking issue.
+
+----
+
+Some macros, especially procedural macros, can generate a surprising amount of
+code, which can slow down compile times. This is hard to detect because the
+generated code is normally invisible to the programmer.
+
+This flag helps identify such cases. When enabled, the compiler measures the
+effect on code size of all used macros and prints a table summarizing that
+effect. For each distinct macro, it counts how many times it is used, and the
+net effect on code size (in terms of lines of code, and bytes of code). The
+code size evaluation uses the compiler's internal pretty-printing, and so will
+be independent of the formatting in the original code.
+
+Note that the net effect of a macro may be negative. E.g. the `cfg!` and
+`#[test]` macros often strip out code.
+
+If a macro is identified as causing a large increase in code size, it is worth
+using `cargo expand` to inspect the post-expansion code, which includes the
+code produced by all macros. It may be possible to optimize the macro to
+produce smaller code, or it may be possible to avoid using it altogether.
diff --git a/src/doc/unstable-book/src/language-features/asm-experimental-arch.md b/src/doc/unstable-book/src/language-features/asm-experimental-arch.md
index d9566c9f55c..121f9493435 100644
--- a/src/doc/unstable-book/src/language-features/asm-experimental-arch.md
+++ b/src/doc/unstable-book/src/language-features/asm-experimental-arch.md
@@ -19,6 +19,7 @@ This feature tracks `asm!` and `global_asm!` support for the following architect
 - M68k
 - CSKY
 - SPARC
+- LoongArch32
 
 ## Register classes
 
@@ -53,6 +54,8 @@ This feature tracks `asm!` and `global_asm!` support for the following architect
 | CSKY         | `freg`         | `f[0-31]`                          | `f`                  |
 | SPARC        | `reg`          | `r[2-29]`                          | `r`                  |
 | SPARC        | `yreg`         | `y`                                | Only clobbers        |
+| LoongArch32  | `reg`          | `$r1`, `$r[4-20]`, `$r[23,30]`     | `r`                  |
+| LoongArch32  | `freg`         | `$f[0-31]`                         | `f`                  |
 
 > **Notes**:
 > - NVPTX doesn't have a fixed register set, so named registers are not supported.
@@ -91,6 +94,8 @@ This feature tracks `asm!` and `global_asm!` support for the following architect
 | CSKY         | `freg`                          | None           | `f32`,                                  |
 | SPARC        | `reg`                           | None           | `i8`, `i16`, `i32`, `i64` (SPARC64 only) |
 | SPARC        | `yreg`                          | N/A            | Only clobbers                           |
+| LoongArch32  | `reg`                           | None           | `i8`, `i16`, `i32`, `f32`               |
+| LoongArch32  | `freg`                          | None           | `f32`, `f64`                            |
 
 ## Register aliases
 
diff --git a/src/doc/unstable-book/src/language-features/unsized-locals.md b/src/doc/unstable-book/src/language-features/unsized-locals.md
deleted file mode 100644
index d5b01a3d616..00000000000
--- a/src/doc/unstable-book/src/language-features/unsized-locals.md
+++ /dev/null
@@ -1,175 +0,0 @@
-# `unsized_locals`
-
-The tracking issue for this feature is: [#48055]
-
-[#48055]: https://github.com/rust-lang/rust/issues/48055
-
-------------------------
-
-This implements [RFC1909]. When turned on, you can have unsized arguments and locals:
-
-[RFC1909]: https://github.com/rust-lang/rfcs/blob/master/text/1909-unsized-rvalues.md
-
-```rust
-#![allow(incomplete_features)]
-#![feature(unsized_locals, unsized_fn_params)]
-
-use std::any::Any;
-
-fn main() {
-    let x: Box<dyn Any> = Box::new(42);
-    let x: dyn Any = *x;
-    //  ^ unsized local variable
-    //               ^^ unsized temporary
-    foo(x);
-}
-
-fn foo(_: dyn Any) {}
-//     ^^^^^^ unsized argument
-```
-
-The RFC still forbids the following unsized expressions:
-
-```rust,compile_fail
-#![feature(unsized_locals)]
-
-use std::any::Any;
-
-struct MyStruct<T: ?Sized> {
-    content: T,
-}
-
-struct MyTupleStruct<T: ?Sized>(T);
-
-fn answer() -> Box<dyn Any> {
-    Box::new(42)
-}
-
-fn main() {
-    // You CANNOT have unsized statics.
-    static X: dyn Any = *answer();  // ERROR
-    const Y: dyn Any = *answer();  // ERROR
-
-    // You CANNOT have struct initialized unsized.
-    MyStruct { content: *answer() };  // ERROR
-    MyTupleStruct(*answer());  // ERROR
-    (42, *answer());  // ERROR
-
-    // You CANNOT have unsized return types.
-    fn my_function() -> dyn Any { *answer() }  // ERROR
-
-    // You CAN have unsized local variables...
-    let mut x: dyn Any = *answer();  // OK
-    // ...but you CANNOT reassign to them.
-    x = *answer();  // ERROR
-
-    // You CANNOT even initialize them separately.
-    let y: dyn Any;  // OK
-    y = *answer();  // ERROR
-
-    // Not mentioned in the RFC, but by-move captured variables are also Sized.
-    let x: dyn Any = *answer();
-    (move || {  // ERROR
-        let y = x;
-    })();
-
-    // You CAN create a closure with unsized arguments,
-    // but you CANNOT call it.
-    // This is an implementation detail and may be changed in the future.
-    let f = |x: dyn Any| {};
-    f(*answer());  // ERROR
-}
-```
-
-## By-value trait objects
-
-With this feature, you can have by-value `self` arguments without `Self: Sized` bounds.
-
-```rust
-#![feature(unsized_fn_params)]
-
-trait Foo {
-    fn foo(self) {}
-}
-
-impl<T: ?Sized> Foo for T {}
-
-fn main() {
-    let slice: Box<[i32]> = Box::new([1, 2, 3]);
-    <[i32] as Foo>::foo(*slice);
-}
-```
-
-And `Foo` will also be object-safe.
-
-```rust
-#![feature(unsized_fn_params)]
-
-trait Foo {
-    fn foo(self) {}
-}
-
-impl<T: ?Sized> Foo for T {}
-
-fn main () {
-    let slice: Box<dyn Foo> = Box::new([1, 2, 3]);
-    // doesn't compile yet
-    <dyn Foo as Foo>::foo(*slice);
-}
-```
-
-One of the objectives of this feature is to allow `Box<dyn FnOnce>`.
-
-## Variable length arrays
-
-The RFC also describes an extension to the array literal syntax: `[e; dyn n]`. In the syntax, `n` isn't necessarily a constant expression. The array is dynamically allocated on the stack and has the type of `[T]`, instead of `[T; n]`.
-
-```rust,ignore (not-yet-implemented)
-#![feature(unsized_locals)]
-
-fn mergesort<T: Ord>(a: &mut [T]) {
-    let mut tmp = [T; dyn a.len()];
-    // ...
-}
-
-fn main() {
-    let mut a = [3, 1, 5, 6];
-    mergesort(&mut a);
-    assert_eq!(a, [1, 3, 5, 6]);
-}
-```
-
-VLAs are not implemented yet. The syntax isn't final, either. We may need an alternative syntax for Rust 2015 because, in Rust 2015, expressions like `[e; dyn(1)]` would be ambiguous. One possible alternative proposed in the RFC is `[e; n]`: if `n` captures one or more local variables, then it is considered as `[e; dyn n]`.
-
-## Advisory on stack usage
-
-It's advised not to casually use the `#![feature(unsized_locals)]` feature. Typical use-cases are:
-
-- When you need a by-value trait objects.
-- When you really need a fast allocation of small temporary arrays.
-
-Another pitfall is repetitive allocation and temporaries. Currently the compiler simply extends the stack frame every time it encounters an unsized assignment. So for example, the code
-
-```rust
-#![feature(unsized_locals)]
-
-fn main() {
-    let x: Box<[i32]> = Box::new([1, 2, 3, 4, 5]);
-    let _x = {{{{{{{{{{*x}}}}}}}}}};
-}
-```
-
-and the code
-
-```rust
-#![feature(unsized_locals)]
-
-fn main() {
-    for _ in 0..10 {
-        let x: Box<[i32]> = Box::new([1, 2, 3, 4, 5]);
-        let _x = *x;
-    }
-}
-```
-
-will unnecessarily extend the stack frame.
diff --git a/src/etc/completions/x.fish b/src/etc/completions/x.fish
index 10a4e684e33..a030f45830e 100644
--- a/src/etc/completions/x.fish
+++ b/src/etc/completions/x.fish
@@ -26,7 +26,7 @@ end
 
 complete -c x -n "__fish_x_needs_command" -l config -d 'TOML configuration file for build' -r -F
 complete -c x -n "__fish_x_needs_command" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x -n "__fish_x_needs_command" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x -n "__fish_x_needs_command" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x -n "__fish_x_needs_command" -l host -d 'host targets to build' -r -f
 complete -c x -n "__fish_x_needs_command" -l target -d 'target targets to build' -r -f
 complete -c x -n "__fish_x_needs_command" -l exclude -d 'build paths to exclude' -r -F
@@ -78,7 +78,7 @@ complete -c x -n "__fish_x_needs_command" -a "vendor" -d 'Vendor dependencies'
 complete -c x -n "__fish_x_needs_command" -a "perf" -d 'Perform profiling and benchmarking of the compiler using `rustc-perf`'
 complete -c x -n "__fish_x_using_subcommand build" -l config -d 'TOML configuration file for build' -r -F
 complete -c x -n "__fish_x_using_subcommand build" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x -n "__fish_x_using_subcommand build" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x -n "__fish_x_using_subcommand build" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x -n "__fish_x_using_subcommand build" -l host -d 'host targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand build" -l target -d 'target targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand build" -l exclude -d 'build paths to exclude' -r -F
@@ -113,7 +113,7 @@ complete -c x -n "__fish_x_using_subcommand build" -l skip-std-check-if-no-downl
 complete -c x -n "__fish_x_using_subcommand build" -s h -l help -d 'Print help (see more with \'--help\')'
 complete -c x -n "__fish_x_using_subcommand check" -l config -d 'TOML configuration file for build' -r -F
 complete -c x -n "__fish_x_using_subcommand check" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x -n "__fish_x_using_subcommand check" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x -n "__fish_x_using_subcommand check" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x -n "__fish_x_using_subcommand check" -l host -d 'host targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand check" -l target -d 'target targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand check" -l exclude -d 'build paths to exclude' -r -F
@@ -153,7 +153,7 @@ complete -c x -n "__fish_x_using_subcommand clippy" -s W -d 'clippy lints to war
 complete -c x -n "__fish_x_using_subcommand clippy" -s F -d 'clippy lints to forbid' -r
 complete -c x -n "__fish_x_using_subcommand clippy" -l config -d 'TOML configuration file for build' -r -F
 complete -c x -n "__fish_x_using_subcommand clippy" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x -n "__fish_x_using_subcommand clippy" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x -n "__fish_x_using_subcommand clippy" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x -n "__fish_x_using_subcommand clippy" -l host -d 'host targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand clippy" -l target -d 'target targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand clippy" -l exclude -d 'build paths to exclude' -r -F
@@ -191,7 +191,7 @@ complete -c x -n "__fish_x_using_subcommand clippy" -l skip-std-check-if-no-down
 complete -c x -n "__fish_x_using_subcommand clippy" -s h -l help -d 'Print help (see more with \'--help\')'
 complete -c x -n "__fish_x_using_subcommand fix" -l config -d 'TOML configuration file for build' -r -F
 complete -c x -n "__fish_x_using_subcommand fix" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x -n "__fish_x_using_subcommand fix" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x -n "__fish_x_using_subcommand fix" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x -n "__fish_x_using_subcommand fix" -l host -d 'host targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand fix" -l target -d 'target targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand fix" -l exclude -d 'build paths to exclude' -r -F
@@ -226,7 +226,7 @@ complete -c x -n "__fish_x_using_subcommand fix" -l skip-std-check-if-no-downloa
 complete -c x -n "__fish_x_using_subcommand fix" -s h -l help -d 'Print help (see more with \'--help\')'
 complete -c x -n "__fish_x_using_subcommand fmt" -l config -d 'TOML configuration file for build' -r -F
 complete -c x -n "__fish_x_using_subcommand fmt" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x -n "__fish_x_using_subcommand fmt" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x -n "__fish_x_using_subcommand fmt" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x -n "__fish_x_using_subcommand fmt" -l host -d 'host targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand fmt" -l target -d 'target targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand fmt" -l exclude -d 'build paths to exclude' -r -F
@@ -263,7 +263,7 @@ complete -c x -n "__fish_x_using_subcommand fmt" -l skip-std-check-if-no-downloa
 complete -c x -n "__fish_x_using_subcommand fmt" -s h -l help -d 'Print help (see more with \'--help\')'
 complete -c x -n "__fish_x_using_subcommand doc" -l config -d 'TOML configuration file for build' -r -F
 complete -c x -n "__fish_x_using_subcommand doc" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x -n "__fish_x_using_subcommand doc" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x -n "__fish_x_using_subcommand doc" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x -n "__fish_x_using_subcommand doc" -l host -d 'host targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand doc" -l target -d 'target targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand doc" -l exclude -d 'build paths to exclude' -r -F
@@ -306,7 +306,7 @@ complete -c x -n "__fish_x_using_subcommand test" -l pass -d 'force {check,build
 complete -c x -n "__fish_x_using_subcommand test" -l run -d 'whether to execute run-* tests' -r
 complete -c x -n "__fish_x_using_subcommand test" -l config -d 'TOML configuration file for build' -r -F
 complete -c x -n "__fish_x_using_subcommand test" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x -n "__fish_x_using_subcommand test" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x -n "__fish_x_using_subcommand test" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x -n "__fish_x_using_subcommand test" -l host -d 'host targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand test" -l target -d 'target targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand test" -l exclude -d 'build paths to exclude' -r -F
@@ -350,7 +350,7 @@ complete -c x -n "__fish_x_using_subcommand test" -s h -l help -d 'Print help (s
 complete -c x -n "__fish_x_using_subcommand miri" -l test-args -d 'extra arguments to be passed for the test tool being used (e.g. libtest, compiletest or rustdoc)' -r
 complete -c x -n "__fish_x_using_subcommand miri" -l config -d 'TOML configuration file for build' -r -F
 complete -c x -n "__fish_x_using_subcommand miri" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x -n "__fish_x_using_subcommand miri" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x -n "__fish_x_using_subcommand miri" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x -n "__fish_x_using_subcommand miri" -l host -d 'host targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand miri" -l target -d 'target targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand miri" -l exclude -d 'build paths to exclude' -r -F
@@ -389,7 +389,7 @@ complete -c x -n "__fish_x_using_subcommand miri" -s h -l help -d 'Print help (s
 complete -c x -n "__fish_x_using_subcommand bench" -l test-args -r
 complete -c x -n "__fish_x_using_subcommand bench" -l config -d 'TOML configuration file for build' -r -F
 complete -c x -n "__fish_x_using_subcommand bench" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x -n "__fish_x_using_subcommand bench" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x -n "__fish_x_using_subcommand bench" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x -n "__fish_x_using_subcommand bench" -l host -d 'host targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand bench" -l target -d 'target targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand bench" -l exclude -d 'build paths to exclude' -r -F
@@ -425,7 +425,7 @@ complete -c x -n "__fish_x_using_subcommand bench" -s h -l help -d 'Print help (
 complete -c x -n "__fish_x_using_subcommand clean" -l stage -d 'Clean a specific stage without touching other artifacts. By default, every stage is cleaned if this option is not used' -r
 complete -c x -n "__fish_x_using_subcommand clean" -l config -d 'TOML configuration file for build' -r -F
 complete -c x -n "__fish_x_using_subcommand clean" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x -n "__fish_x_using_subcommand clean" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x -n "__fish_x_using_subcommand clean" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x -n "__fish_x_using_subcommand clean" -l host -d 'host targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand clean" -l target -d 'target targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand clean" -l exclude -d 'build paths to exclude' -r -F
@@ -460,7 +460,7 @@ complete -c x -n "__fish_x_using_subcommand clean" -l skip-std-check-if-no-downl
 complete -c x -n "__fish_x_using_subcommand clean" -s h -l help -d 'Print help (see more with \'--help\')'
 complete -c x -n "__fish_x_using_subcommand dist" -l config -d 'TOML configuration file for build' -r -F
 complete -c x -n "__fish_x_using_subcommand dist" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x -n "__fish_x_using_subcommand dist" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x -n "__fish_x_using_subcommand dist" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x -n "__fish_x_using_subcommand dist" -l host -d 'host targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand dist" -l target -d 'target targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand dist" -l exclude -d 'build paths to exclude' -r -F
@@ -495,7 +495,7 @@ complete -c x -n "__fish_x_using_subcommand dist" -l skip-std-check-if-no-downlo
 complete -c x -n "__fish_x_using_subcommand dist" -s h -l help -d 'Print help (see more with \'--help\')'
 complete -c x -n "__fish_x_using_subcommand install" -l config -d 'TOML configuration file for build' -r -F
 complete -c x -n "__fish_x_using_subcommand install" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x -n "__fish_x_using_subcommand install" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x -n "__fish_x_using_subcommand install" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x -n "__fish_x_using_subcommand install" -l host -d 'host targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand install" -l target -d 'target targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand install" -l exclude -d 'build paths to exclude' -r -F
@@ -531,7 +531,7 @@ complete -c x -n "__fish_x_using_subcommand install" -s h -l help -d 'Print help
 complete -c x -n "__fish_x_using_subcommand run" -l args -d 'arguments for the tool' -r
 complete -c x -n "__fish_x_using_subcommand run" -l config -d 'TOML configuration file for build' -r -F
 complete -c x -n "__fish_x_using_subcommand run" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x -n "__fish_x_using_subcommand run" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x -n "__fish_x_using_subcommand run" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x -n "__fish_x_using_subcommand run" -l host -d 'host targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand run" -l target -d 'target targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand run" -l exclude -d 'build paths to exclude' -r -F
@@ -566,7 +566,7 @@ complete -c x -n "__fish_x_using_subcommand run" -l skip-std-check-if-no-downloa
 complete -c x -n "__fish_x_using_subcommand run" -s h -l help -d 'Print help (see more with \'--help\')'
 complete -c x -n "__fish_x_using_subcommand setup" -l config -d 'TOML configuration file for build' -r -F
 complete -c x -n "__fish_x_using_subcommand setup" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x -n "__fish_x_using_subcommand setup" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x -n "__fish_x_using_subcommand setup" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x -n "__fish_x_using_subcommand setup" -l host -d 'host targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand setup" -l target -d 'target targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand setup" -l exclude -d 'build paths to exclude' -r -F
@@ -601,7 +601,7 @@ complete -c x -n "__fish_x_using_subcommand setup" -l skip-std-check-if-no-downl
 complete -c x -n "__fish_x_using_subcommand setup" -s h -l help -d 'Print help (see more with \'--help\')'
 complete -c x -n "__fish_x_using_subcommand suggest" -l config -d 'TOML configuration file for build' -r -F
 complete -c x -n "__fish_x_using_subcommand suggest" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x -n "__fish_x_using_subcommand suggest" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x -n "__fish_x_using_subcommand suggest" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x -n "__fish_x_using_subcommand suggest" -l host -d 'host targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand suggest" -l target -d 'target targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand suggest" -l exclude -d 'build paths to exclude' -r -F
@@ -638,7 +638,7 @@ complete -c x -n "__fish_x_using_subcommand suggest" -s h -l help -d 'Print help
 complete -c x -n "__fish_x_using_subcommand vendor" -l sync -d 'Additional `Cargo.toml` to sync and vendor' -r -F
 complete -c x -n "__fish_x_using_subcommand vendor" -l config -d 'TOML configuration file for build' -r -F
 complete -c x -n "__fish_x_using_subcommand vendor" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x -n "__fish_x_using_subcommand vendor" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x -n "__fish_x_using_subcommand vendor" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x -n "__fish_x_using_subcommand vendor" -l host -d 'host targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand vendor" -l target -d 'target targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand vendor" -l exclude -d 'build paths to exclude' -r -F
@@ -674,7 +674,7 @@ complete -c x -n "__fish_x_using_subcommand vendor" -l skip-std-check-if-no-down
 complete -c x -n "__fish_x_using_subcommand vendor" -s h -l help -d 'Print help (see more with \'--help\')'
 complete -c x -n "__fish_x_using_subcommand perf; and not __fish_seen_subcommand_from eprintln samply cachegrind benchmark compare" -l config -d 'TOML configuration file for build' -r -F
 complete -c x -n "__fish_x_using_subcommand perf; and not __fish_seen_subcommand_from eprintln samply cachegrind benchmark compare" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x -n "__fish_x_using_subcommand perf; and not __fish_seen_subcommand_from eprintln samply cachegrind benchmark compare" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x -n "__fish_x_using_subcommand perf; and not __fish_seen_subcommand_from eprintln samply cachegrind benchmark compare" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x -n "__fish_x_using_subcommand perf; and not __fish_seen_subcommand_from eprintln samply cachegrind benchmark compare" -l host -d 'host targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand perf; and not __fish_seen_subcommand_from eprintln samply cachegrind benchmark compare" -l target -d 'target targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand perf; and not __fish_seen_subcommand_from eprintln samply cachegrind benchmark compare" -l exclude -d 'build paths to exclude' -r -F
@@ -718,7 +718,7 @@ complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_fro
 complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_from eprintln" -l profiles -d 'Select the profiles that should be benchmarked' -r -f -a "{Check\t'',Debug\t'',Doc\t'',Opt\t'',Clippy\t''}"
 complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_from eprintln" -l config -d 'TOML configuration file for build' -r -F
 complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_from eprintln" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_from eprintln" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_from eprintln" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_from eprintln" -l host -d 'host targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_from eprintln" -l target -d 'target targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_from eprintln" -l skip -d 'build paths to skip' -r -F
@@ -756,7 +756,7 @@ complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_fro
 complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_from samply" -l profiles -d 'Select the profiles that should be benchmarked' -r -f -a "{Check\t'',Debug\t'',Doc\t'',Opt\t'',Clippy\t''}"
 complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_from samply" -l config -d 'TOML configuration file for build' -r -F
 complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_from samply" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_from samply" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_from samply" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_from samply" -l host -d 'host targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_from samply" -l target -d 'target targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_from samply" -l skip -d 'build paths to skip' -r -F
@@ -794,7 +794,7 @@ complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_fro
 complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_from cachegrind" -l profiles -d 'Select the profiles that should be benchmarked' -r -f -a "{Check\t'',Debug\t'',Doc\t'',Opt\t'',Clippy\t''}"
 complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_from cachegrind" -l config -d 'TOML configuration file for build' -r -F
 complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_from cachegrind" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_from cachegrind" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_from cachegrind" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_from cachegrind" -l host -d 'host targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_from cachegrind" -l target -d 'target targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_from cachegrind" -l skip -d 'build paths to skip' -r -F
@@ -832,7 +832,7 @@ complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_fro
 complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_from benchmark" -l profiles -d 'Select the profiles that should be benchmarked' -r -f -a "{Check\t'',Debug\t'',Doc\t'',Opt\t'',Clippy\t''}"
 complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_from benchmark" -l config -d 'TOML configuration file for build' -r -F
 complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_from benchmark" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_from benchmark" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_from benchmark" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_from benchmark" -l host -d 'host targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_from benchmark" -l target -d 'target targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_from benchmark" -l skip -d 'build paths to skip' -r -F
@@ -866,7 +866,7 @@ complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_fro
 complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_from benchmark" -s h -l help -d 'Print help (see more with \'--help\')'
 complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_from compare" -l config -d 'TOML configuration file for build' -r -F
 complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_from compare" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_from compare" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_from compare" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_from compare" -l host -d 'host targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_from compare" -l target -d 'target targets to build' -r -f
 complete -c x -n "__fish_x_using_subcommand perf; and __fish_seen_subcommand_from compare" -l exclude -d 'build paths to exclude' -r -F
diff --git a/src/etc/completions/x.ps1 b/src/etc/completions/x.ps1
index 23d8fe0cdd3..a891a9db332 100644
--- a/src/etc/completions/x.ps1
+++ b/src/etc/completions/x.ps1
@@ -23,7 +23,7 @@ Register-ArgumentCompleter -Native -CommandName 'x' -ScriptBlock {
         'x' {
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--exclude', '--exclude', [CompletionResultType]::ParameterName, 'build paths to exclude')
@@ -82,7 +82,7 @@ Register-ArgumentCompleter -Native -CommandName 'x' -ScriptBlock {
         'x;build' {
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--exclude', '--exclude', [CompletionResultType]::ParameterName, 'build paths to exclude')
@@ -124,7 +124,7 @@ Register-ArgumentCompleter -Native -CommandName 'x' -ScriptBlock {
         'x;check' {
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--exclude', '--exclude', [CompletionResultType]::ParameterName, 'build paths to exclude')
@@ -171,7 +171,7 @@ Register-ArgumentCompleter -Native -CommandName 'x' -ScriptBlock {
             [CompletionResult]::new('-F', '-F ', [CompletionResultType]::ParameterName, 'clippy lints to forbid')
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--exclude', '--exclude', [CompletionResultType]::ParameterName, 'build paths to exclude')
@@ -216,7 +216,7 @@ Register-ArgumentCompleter -Native -CommandName 'x' -ScriptBlock {
         'x;fix' {
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--exclude', '--exclude', [CompletionResultType]::ParameterName, 'build paths to exclude')
@@ -258,7 +258,7 @@ Register-ArgumentCompleter -Native -CommandName 'x' -ScriptBlock {
         'x;fmt' {
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--exclude', '--exclude', [CompletionResultType]::ParameterName, 'build paths to exclude')
@@ -302,7 +302,7 @@ Register-ArgumentCompleter -Native -CommandName 'x' -ScriptBlock {
         'x;doc' {
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--exclude', '--exclude', [CompletionResultType]::ParameterName, 'build paths to exclude')
@@ -352,7 +352,7 @@ Register-ArgumentCompleter -Native -CommandName 'x' -ScriptBlock {
             [CompletionResult]::new('--run', '--run', [CompletionResultType]::ParameterName, 'whether to execute run-* tests')
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--exclude', '--exclude', [CompletionResultType]::ParameterName, 'build paths to exclude')
@@ -403,7 +403,7 @@ Register-ArgumentCompleter -Native -CommandName 'x' -ScriptBlock {
             [CompletionResult]::new('--test-args', '--test-args', [CompletionResultType]::ParameterName, 'extra arguments to be passed for the test tool being used (e.g. libtest, compiletest or rustdoc)')
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--exclude', '--exclude', [CompletionResultType]::ParameterName, 'build paths to exclude')
@@ -449,7 +449,7 @@ Register-ArgumentCompleter -Native -CommandName 'x' -ScriptBlock {
             [CompletionResult]::new('--test-args', '--test-args', [CompletionResultType]::ParameterName, 'test-args')
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--exclude', '--exclude', [CompletionResultType]::ParameterName, 'build paths to exclude')
@@ -492,7 +492,7 @@ Register-ArgumentCompleter -Native -CommandName 'x' -ScriptBlock {
             [CompletionResult]::new('--stage', '--stage', [CompletionResultType]::ParameterName, 'Clean a specific stage without touching other artifacts. By default, every stage is cleaned if this option is not used')
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--exclude', '--exclude', [CompletionResultType]::ParameterName, 'build paths to exclude')
@@ -534,7 +534,7 @@ Register-ArgumentCompleter -Native -CommandName 'x' -ScriptBlock {
         'x;dist' {
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--exclude', '--exclude', [CompletionResultType]::ParameterName, 'build paths to exclude')
@@ -576,7 +576,7 @@ Register-ArgumentCompleter -Native -CommandName 'x' -ScriptBlock {
         'x;install' {
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--exclude', '--exclude', [CompletionResultType]::ParameterName, 'build paths to exclude')
@@ -619,7 +619,7 @@ Register-ArgumentCompleter -Native -CommandName 'x' -ScriptBlock {
             [CompletionResult]::new('--args', '--args', [CompletionResultType]::ParameterName, 'arguments for the tool')
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--exclude', '--exclude', [CompletionResultType]::ParameterName, 'build paths to exclude')
@@ -661,7 +661,7 @@ Register-ArgumentCompleter -Native -CommandName 'x' -ScriptBlock {
         'x;setup' {
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--exclude', '--exclude', [CompletionResultType]::ParameterName, 'build paths to exclude')
@@ -703,7 +703,7 @@ Register-ArgumentCompleter -Native -CommandName 'x' -ScriptBlock {
         'x;suggest' {
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--exclude', '--exclude', [CompletionResultType]::ParameterName, 'build paths to exclude')
@@ -747,7 +747,7 @@ Register-ArgumentCompleter -Native -CommandName 'x' -ScriptBlock {
             [CompletionResult]::new('--sync', '--sync', [CompletionResultType]::ParameterName, 'Additional `Cargo.toml` to sync and vendor')
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--exclude', '--exclude', [CompletionResultType]::ParameterName, 'build paths to exclude')
@@ -790,7 +790,7 @@ Register-ArgumentCompleter -Native -CommandName 'x' -ScriptBlock {
         'x;perf' {
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--exclude', '--exclude', [CompletionResultType]::ParameterName, 'build paths to exclude')
@@ -841,7 +841,7 @@ Register-ArgumentCompleter -Native -CommandName 'x' -ScriptBlock {
             [CompletionResult]::new('--profiles', '--profiles', [CompletionResultType]::ParameterName, 'Select the profiles that should be benchmarked')
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--skip', '--skip', [CompletionResultType]::ParameterName, 'build paths to skip')
@@ -886,7 +886,7 @@ Register-ArgumentCompleter -Native -CommandName 'x' -ScriptBlock {
             [CompletionResult]::new('--profiles', '--profiles', [CompletionResultType]::ParameterName, 'Select the profiles that should be benchmarked')
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--skip', '--skip', [CompletionResultType]::ParameterName, 'build paths to skip')
@@ -931,7 +931,7 @@ Register-ArgumentCompleter -Native -CommandName 'x' -ScriptBlock {
             [CompletionResult]::new('--profiles', '--profiles', [CompletionResultType]::ParameterName, 'Select the profiles that should be benchmarked')
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--skip', '--skip', [CompletionResultType]::ParameterName, 'build paths to skip')
@@ -976,7 +976,7 @@ Register-ArgumentCompleter -Native -CommandName 'x' -ScriptBlock {
             [CompletionResult]::new('--profiles', '--profiles', [CompletionResultType]::ParameterName, 'Select the profiles that should be benchmarked')
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--skip', '--skip', [CompletionResultType]::ParameterName, 'build paths to skip')
@@ -1017,7 +1017,7 @@ Register-ArgumentCompleter -Native -CommandName 'x' -ScriptBlock {
         'x;perf;compare' {
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--exclude', '--exclude', [CompletionResultType]::ParameterName, 'build paths to exclude')
diff --git a/src/etc/completions/x.py.fish b/src/etc/completions/x.py.fish
index 1fc5bb12cfb..e6326fcb0bb 100644
--- a/src/etc/completions/x.py.fish
+++ b/src/etc/completions/x.py.fish
@@ -26,7 +26,7 @@ end
 
 complete -c x.py -n "__fish_x.py_needs_command" -l config -d 'TOML configuration file for build' -r -F
 complete -c x.py -n "__fish_x.py_needs_command" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x.py -n "__fish_x.py_needs_command" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x.py -n "__fish_x.py_needs_command" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x.py -n "__fish_x.py_needs_command" -l host -d 'host targets to build' -r -f
 complete -c x.py -n "__fish_x.py_needs_command" -l target -d 'target targets to build' -r -f
 complete -c x.py -n "__fish_x.py_needs_command" -l exclude -d 'build paths to exclude' -r -F
@@ -78,7 +78,7 @@ complete -c x.py -n "__fish_x.py_needs_command" -a "vendor" -d 'Vendor dependenc
 complete -c x.py -n "__fish_x.py_needs_command" -a "perf" -d 'Perform profiling and benchmarking of the compiler using `rustc-perf`'
 complete -c x.py -n "__fish_x.py_using_subcommand build" -l config -d 'TOML configuration file for build' -r -F
 complete -c x.py -n "__fish_x.py_using_subcommand build" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x.py -n "__fish_x.py_using_subcommand build" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x.py -n "__fish_x.py_using_subcommand build" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand build" -l host -d 'host targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand build" -l target -d 'target targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand build" -l exclude -d 'build paths to exclude' -r -F
@@ -113,7 +113,7 @@ complete -c x.py -n "__fish_x.py_using_subcommand build" -l skip-std-check-if-no
 complete -c x.py -n "__fish_x.py_using_subcommand build" -s h -l help -d 'Print help (see more with \'--help\')'
 complete -c x.py -n "__fish_x.py_using_subcommand check" -l config -d 'TOML configuration file for build' -r -F
 complete -c x.py -n "__fish_x.py_using_subcommand check" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x.py -n "__fish_x.py_using_subcommand check" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x.py -n "__fish_x.py_using_subcommand check" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand check" -l host -d 'host targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand check" -l target -d 'target targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand check" -l exclude -d 'build paths to exclude' -r -F
@@ -153,7 +153,7 @@ complete -c x.py -n "__fish_x.py_using_subcommand clippy" -s W -d 'clippy lints
 complete -c x.py -n "__fish_x.py_using_subcommand clippy" -s F -d 'clippy lints to forbid' -r
 complete -c x.py -n "__fish_x.py_using_subcommand clippy" -l config -d 'TOML configuration file for build' -r -F
 complete -c x.py -n "__fish_x.py_using_subcommand clippy" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x.py -n "__fish_x.py_using_subcommand clippy" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x.py -n "__fish_x.py_using_subcommand clippy" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand clippy" -l host -d 'host targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand clippy" -l target -d 'target targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand clippy" -l exclude -d 'build paths to exclude' -r -F
@@ -191,7 +191,7 @@ complete -c x.py -n "__fish_x.py_using_subcommand clippy" -l skip-std-check-if-n
 complete -c x.py -n "__fish_x.py_using_subcommand clippy" -s h -l help -d 'Print help (see more with \'--help\')'
 complete -c x.py -n "__fish_x.py_using_subcommand fix" -l config -d 'TOML configuration file for build' -r -F
 complete -c x.py -n "__fish_x.py_using_subcommand fix" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x.py -n "__fish_x.py_using_subcommand fix" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x.py -n "__fish_x.py_using_subcommand fix" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand fix" -l host -d 'host targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand fix" -l target -d 'target targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand fix" -l exclude -d 'build paths to exclude' -r -F
@@ -226,7 +226,7 @@ complete -c x.py -n "__fish_x.py_using_subcommand fix" -l skip-std-check-if-no-d
 complete -c x.py -n "__fish_x.py_using_subcommand fix" -s h -l help -d 'Print help (see more with \'--help\')'
 complete -c x.py -n "__fish_x.py_using_subcommand fmt" -l config -d 'TOML configuration file for build' -r -F
 complete -c x.py -n "__fish_x.py_using_subcommand fmt" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x.py -n "__fish_x.py_using_subcommand fmt" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x.py -n "__fish_x.py_using_subcommand fmt" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand fmt" -l host -d 'host targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand fmt" -l target -d 'target targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand fmt" -l exclude -d 'build paths to exclude' -r -F
@@ -263,7 +263,7 @@ complete -c x.py -n "__fish_x.py_using_subcommand fmt" -l skip-std-check-if-no-d
 complete -c x.py -n "__fish_x.py_using_subcommand fmt" -s h -l help -d 'Print help (see more with \'--help\')'
 complete -c x.py -n "__fish_x.py_using_subcommand doc" -l config -d 'TOML configuration file for build' -r -F
 complete -c x.py -n "__fish_x.py_using_subcommand doc" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x.py -n "__fish_x.py_using_subcommand doc" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x.py -n "__fish_x.py_using_subcommand doc" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand doc" -l host -d 'host targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand doc" -l target -d 'target targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand doc" -l exclude -d 'build paths to exclude' -r -F
@@ -306,7 +306,7 @@ complete -c x.py -n "__fish_x.py_using_subcommand test" -l pass -d 'force {check
 complete -c x.py -n "__fish_x.py_using_subcommand test" -l run -d 'whether to execute run-* tests' -r
 complete -c x.py -n "__fish_x.py_using_subcommand test" -l config -d 'TOML configuration file for build' -r -F
 complete -c x.py -n "__fish_x.py_using_subcommand test" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x.py -n "__fish_x.py_using_subcommand test" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x.py -n "__fish_x.py_using_subcommand test" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand test" -l host -d 'host targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand test" -l target -d 'target targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand test" -l exclude -d 'build paths to exclude' -r -F
@@ -350,7 +350,7 @@ complete -c x.py -n "__fish_x.py_using_subcommand test" -s h -l help -d 'Print h
 complete -c x.py -n "__fish_x.py_using_subcommand miri" -l test-args -d 'extra arguments to be passed for the test tool being used (e.g. libtest, compiletest or rustdoc)' -r
 complete -c x.py -n "__fish_x.py_using_subcommand miri" -l config -d 'TOML configuration file for build' -r -F
 complete -c x.py -n "__fish_x.py_using_subcommand miri" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x.py -n "__fish_x.py_using_subcommand miri" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x.py -n "__fish_x.py_using_subcommand miri" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand miri" -l host -d 'host targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand miri" -l target -d 'target targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand miri" -l exclude -d 'build paths to exclude' -r -F
@@ -389,7 +389,7 @@ complete -c x.py -n "__fish_x.py_using_subcommand miri" -s h -l help -d 'Print h
 complete -c x.py -n "__fish_x.py_using_subcommand bench" -l test-args -r
 complete -c x.py -n "__fish_x.py_using_subcommand bench" -l config -d 'TOML configuration file for build' -r -F
 complete -c x.py -n "__fish_x.py_using_subcommand bench" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x.py -n "__fish_x.py_using_subcommand bench" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x.py -n "__fish_x.py_using_subcommand bench" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand bench" -l host -d 'host targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand bench" -l target -d 'target targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand bench" -l exclude -d 'build paths to exclude' -r -F
@@ -425,7 +425,7 @@ complete -c x.py -n "__fish_x.py_using_subcommand bench" -s h -l help -d 'Print
 complete -c x.py -n "__fish_x.py_using_subcommand clean" -l stage -d 'Clean a specific stage without touching other artifacts. By default, every stage is cleaned if this option is not used' -r
 complete -c x.py -n "__fish_x.py_using_subcommand clean" -l config -d 'TOML configuration file for build' -r -F
 complete -c x.py -n "__fish_x.py_using_subcommand clean" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x.py -n "__fish_x.py_using_subcommand clean" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x.py -n "__fish_x.py_using_subcommand clean" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand clean" -l host -d 'host targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand clean" -l target -d 'target targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand clean" -l exclude -d 'build paths to exclude' -r -F
@@ -460,7 +460,7 @@ complete -c x.py -n "__fish_x.py_using_subcommand clean" -l skip-std-check-if-no
 complete -c x.py -n "__fish_x.py_using_subcommand clean" -s h -l help -d 'Print help (see more with \'--help\')'
 complete -c x.py -n "__fish_x.py_using_subcommand dist" -l config -d 'TOML configuration file for build' -r -F
 complete -c x.py -n "__fish_x.py_using_subcommand dist" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x.py -n "__fish_x.py_using_subcommand dist" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x.py -n "__fish_x.py_using_subcommand dist" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand dist" -l host -d 'host targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand dist" -l target -d 'target targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand dist" -l exclude -d 'build paths to exclude' -r -F
@@ -495,7 +495,7 @@ complete -c x.py -n "__fish_x.py_using_subcommand dist" -l skip-std-check-if-no-
 complete -c x.py -n "__fish_x.py_using_subcommand dist" -s h -l help -d 'Print help (see more with \'--help\')'
 complete -c x.py -n "__fish_x.py_using_subcommand install" -l config -d 'TOML configuration file for build' -r -F
 complete -c x.py -n "__fish_x.py_using_subcommand install" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x.py -n "__fish_x.py_using_subcommand install" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x.py -n "__fish_x.py_using_subcommand install" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand install" -l host -d 'host targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand install" -l target -d 'target targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand install" -l exclude -d 'build paths to exclude' -r -F
@@ -531,7 +531,7 @@ complete -c x.py -n "__fish_x.py_using_subcommand install" -s h -l help -d 'Prin
 complete -c x.py -n "__fish_x.py_using_subcommand run" -l args -d 'arguments for the tool' -r
 complete -c x.py -n "__fish_x.py_using_subcommand run" -l config -d 'TOML configuration file for build' -r -F
 complete -c x.py -n "__fish_x.py_using_subcommand run" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x.py -n "__fish_x.py_using_subcommand run" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x.py -n "__fish_x.py_using_subcommand run" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand run" -l host -d 'host targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand run" -l target -d 'target targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand run" -l exclude -d 'build paths to exclude' -r -F
@@ -566,7 +566,7 @@ complete -c x.py -n "__fish_x.py_using_subcommand run" -l skip-std-check-if-no-d
 complete -c x.py -n "__fish_x.py_using_subcommand run" -s h -l help -d 'Print help (see more with \'--help\')'
 complete -c x.py -n "__fish_x.py_using_subcommand setup" -l config -d 'TOML configuration file for build' -r -F
 complete -c x.py -n "__fish_x.py_using_subcommand setup" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x.py -n "__fish_x.py_using_subcommand setup" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x.py -n "__fish_x.py_using_subcommand setup" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand setup" -l host -d 'host targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand setup" -l target -d 'target targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand setup" -l exclude -d 'build paths to exclude' -r -F
@@ -601,7 +601,7 @@ complete -c x.py -n "__fish_x.py_using_subcommand setup" -l skip-std-check-if-no
 complete -c x.py -n "__fish_x.py_using_subcommand setup" -s h -l help -d 'Print help (see more with \'--help\')'
 complete -c x.py -n "__fish_x.py_using_subcommand suggest" -l config -d 'TOML configuration file for build' -r -F
 complete -c x.py -n "__fish_x.py_using_subcommand suggest" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x.py -n "__fish_x.py_using_subcommand suggest" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x.py -n "__fish_x.py_using_subcommand suggest" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand suggest" -l host -d 'host targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand suggest" -l target -d 'target targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand suggest" -l exclude -d 'build paths to exclude' -r -F
@@ -638,7 +638,7 @@ complete -c x.py -n "__fish_x.py_using_subcommand suggest" -s h -l help -d 'Prin
 complete -c x.py -n "__fish_x.py_using_subcommand vendor" -l sync -d 'Additional `Cargo.toml` to sync and vendor' -r -F
 complete -c x.py -n "__fish_x.py_using_subcommand vendor" -l config -d 'TOML configuration file for build' -r -F
 complete -c x.py -n "__fish_x.py_using_subcommand vendor" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x.py -n "__fish_x.py_using_subcommand vendor" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x.py -n "__fish_x.py_using_subcommand vendor" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand vendor" -l host -d 'host targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand vendor" -l target -d 'target targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand vendor" -l exclude -d 'build paths to exclude' -r -F
@@ -674,7 +674,7 @@ complete -c x.py -n "__fish_x.py_using_subcommand vendor" -l skip-std-check-if-n
 complete -c x.py -n "__fish_x.py_using_subcommand vendor" -s h -l help -d 'Print help (see more with \'--help\')'
 complete -c x.py -n "__fish_x.py_using_subcommand perf; and not __fish_seen_subcommand_from eprintln samply cachegrind benchmark compare" -l config -d 'TOML configuration file for build' -r -F
 complete -c x.py -n "__fish_x.py_using_subcommand perf; and not __fish_seen_subcommand_from eprintln samply cachegrind benchmark compare" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x.py -n "__fish_x.py_using_subcommand perf; and not __fish_seen_subcommand_from eprintln samply cachegrind benchmark compare" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x.py -n "__fish_x.py_using_subcommand perf; and not __fish_seen_subcommand_from eprintln samply cachegrind benchmark compare" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand perf; and not __fish_seen_subcommand_from eprintln samply cachegrind benchmark compare" -l host -d 'host targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand perf; and not __fish_seen_subcommand_from eprintln samply cachegrind benchmark compare" -l target -d 'target targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand perf; and not __fish_seen_subcommand_from eprintln samply cachegrind benchmark compare" -l exclude -d 'build paths to exclude' -r -F
@@ -718,7 +718,7 @@ complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcomma
 complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcommand_from eprintln" -l profiles -d 'Select the profiles that should be benchmarked' -r -f -a "{Check\t'',Debug\t'',Doc\t'',Opt\t'',Clippy\t''}"
 complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcommand_from eprintln" -l config -d 'TOML configuration file for build' -r -F
 complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcommand_from eprintln" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcommand_from eprintln" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcommand_from eprintln" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcommand_from eprintln" -l host -d 'host targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcommand_from eprintln" -l target -d 'target targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcommand_from eprintln" -l skip -d 'build paths to skip' -r -F
@@ -756,7 +756,7 @@ complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcomma
 complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcommand_from samply" -l profiles -d 'Select the profiles that should be benchmarked' -r -f -a "{Check\t'',Debug\t'',Doc\t'',Opt\t'',Clippy\t''}"
 complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcommand_from samply" -l config -d 'TOML configuration file for build' -r -F
 complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcommand_from samply" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcommand_from samply" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcommand_from samply" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcommand_from samply" -l host -d 'host targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcommand_from samply" -l target -d 'target targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcommand_from samply" -l skip -d 'build paths to skip' -r -F
@@ -794,7 +794,7 @@ complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcomma
 complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcommand_from cachegrind" -l profiles -d 'Select the profiles that should be benchmarked' -r -f -a "{Check\t'',Debug\t'',Doc\t'',Opt\t'',Clippy\t''}"
 complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcommand_from cachegrind" -l config -d 'TOML configuration file for build' -r -F
 complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcommand_from cachegrind" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcommand_from cachegrind" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcommand_from cachegrind" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcommand_from cachegrind" -l host -d 'host targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcommand_from cachegrind" -l target -d 'target targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcommand_from cachegrind" -l skip -d 'build paths to skip' -r -F
@@ -832,7 +832,7 @@ complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcomma
 complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcommand_from benchmark" -l profiles -d 'Select the profiles that should be benchmarked' -r -f -a "{Check\t'',Debug\t'',Doc\t'',Opt\t'',Clippy\t''}"
 complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcommand_from benchmark" -l config -d 'TOML configuration file for build' -r -F
 complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcommand_from benchmark" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcommand_from benchmark" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcommand_from benchmark" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcommand_from benchmark" -l host -d 'host targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcommand_from benchmark" -l target -d 'target targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcommand_from benchmark" -l skip -d 'build paths to skip' -r -F
@@ -866,7 +866,7 @@ complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcomma
 complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcommand_from benchmark" -s h -l help -d 'Print help (see more with \'--help\')'
 complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcommand_from compare" -l config -d 'TOML configuration file for build' -r -F
 complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcommand_from compare" -l build-dir -d 'Build directory, overrides `build.build-dir` in `bootstrap.toml`' -r -f -a "(__fish_complete_directories)"
-complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcommand_from compare" -l build -d 'build target of the stage0 compiler' -r -f
+complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcommand_from compare" -l build -d 'host target of the stage0 compiler' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcommand_from compare" -l host -d 'host targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcommand_from compare" -l target -d 'target targets to build' -r -f
 complete -c x.py -n "__fish_x.py_using_subcommand perf; and __fish_seen_subcommand_from compare" -l exclude -d 'build paths to exclude' -r -F
diff --git a/src/etc/completions/x.py.ps1 b/src/etc/completions/x.py.ps1
index 5d224ac6df4..ee3373b9e75 100644
--- a/src/etc/completions/x.py.ps1
+++ b/src/etc/completions/x.py.ps1
@@ -23,7 +23,7 @@ Register-ArgumentCompleter -Native -CommandName 'x.py' -ScriptBlock {
         'x.py' {
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--exclude', '--exclude', [CompletionResultType]::ParameterName, 'build paths to exclude')
@@ -82,7 +82,7 @@ Register-ArgumentCompleter -Native -CommandName 'x.py' -ScriptBlock {
         'x.py;build' {
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--exclude', '--exclude', [CompletionResultType]::ParameterName, 'build paths to exclude')
@@ -124,7 +124,7 @@ Register-ArgumentCompleter -Native -CommandName 'x.py' -ScriptBlock {
         'x.py;check' {
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--exclude', '--exclude', [CompletionResultType]::ParameterName, 'build paths to exclude')
@@ -171,7 +171,7 @@ Register-ArgumentCompleter -Native -CommandName 'x.py' -ScriptBlock {
             [CompletionResult]::new('-F', '-F ', [CompletionResultType]::ParameterName, 'clippy lints to forbid')
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--exclude', '--exclude', [CompletionResultType]::ParameterName, 'build paths to exclude')
@@ -216,7 +216,7 @@ Register-ArgumentCompleter -Native -CommandName 'x.py' -ScriptBlock {
         'x.py;fix' {
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--exclude', '--exclude', [CompletionResultType]::ParameterName, 'build paths to exclude')
@@ -258,7 +258,7 @@ Register-ArgumentCompleter -Native -CommandName 'x.py' -ScriptBlock {
         'x.py;fmt' {
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--exclude', '--exclude', [CompletionResultType]::ParameterName, 'build paths to exclude')
@@ -302,7 +302,7 @@ Register-ArgumentCompleter -Native -CommandName 'x.py' -ScriptBlock {
         'x.py;doc' {
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--exclude', '--exclude', [CompletionResultType]::ParameterName, 'build paths to exclude')
@@ -352,7 +352,7 @@ Register-ArgumentCompleter -Native -CommandName 'x.py' -ScriptBlock {
             [CompletionResult]::new('--run', '--run', [CompletionResultType]::ParameterName, 'whether to execute run-* tests')
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--exclude', '--exclude', [CompletionResultType]::ParameterName, 'build paths to exclude')
@@ -403,7 +403,7 @@ Register-ArgumentCompleter -Native -CommandName 'x.py' -ScriptBlock {
             [CompletionResult]::new('--test-args', '--test-args', [CompletionResultType]::ParameterName, 'extra arguments to be passed for the test tool being used (e.g. libtest, compiletest or rustdoc)')
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--exclude', '--exclude', [CompletionResultType]::ParameterName, 'build paths to exclude')
@@ -449,7 +449,7 @@ Register-ArgumentCompleter -Native -CommandName 'x.py' -ScriptBlock {
             [CompletionResult]::new('--test-args', '--test-args', [CompletionResultType]::ParameterName, 'test-args')
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--exclude', '--exclude', [CompletionResultType]::ParameterName, 'build paths to exclude')
@@ -492,7 +492,7 @@ Register-ArgumentCompleter -Native -CommandName 'x.py' -ScriptBlock {
             [CompletionResult]::new('--stage', '--stage', [CompletionResultType]::ParameterName, 'Clean a specific stage without touching other artifacts. By default, every stage is cleaned if this option is not used')
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--exclude', '--exclude', [CompletionResultType]::ParameterName, 'build paths to exclude')
@@ -534,7 +534,7 @@ Register-ArgumentCompleter -Native -CommandName 'x.py' -ScriptBlock {
         'x.py;dist' {
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--exclude', '--exclude', [CompletionResultType]::ParameterName, 'build paths to exclude')
@@ -576,7 +576,7 @@ Register-ArgumentCompleter -Native -CommandName 'x.py' -ScriptBlock {
         'x.py;install' {
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--exclude', '--exclude', [CompletionResultType]::ParameterName, 'build paths to exclude')
@@ -619,7 +619,7 @@ Register-ArgumentCompleter -Native -CommandName 'x.py' -ScriptBlock {
             [CompletionResult]::new('--args', '--args', [CompletionResultType]::ParameterName, 'arguments for the tool')
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--exclude', '--exclude', [CompletionResultType]::ParameterName, 'build paths to exclude')
@@ -661,7 +661,7 @@ Register-ArgumentCompleter -Native -CommandName 'x.py' -ScriptBlock {
         'x.py;setup' {
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--exclude', '--exclude', [CompletionResultType]::ParameterName, 'build paths to exclude')
@@ -703,7 +703,7 @@ Register-ArgumentCompleter -Native -CommandName 'x.py' -ScriptBlock {
         'x.py;suggest' {
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--exclude', '--exclude', [CompletionResultType]::ParameterName, 'build paths to exclude')
@@ -747,7 +747,7 @@ Register-ArgumentCompleter -Native -CommandName 'x.py' -ScriptBlock {
             [CompletionResult]::new('--sync', '--sync', [CompletionResultType]::ParameterName, 'Additional `Cargo.toml` to sync and vendor')
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--exclude', '--exclude', [CompletionResultType]::ParameterName, 'build paths to exclude')
@@ -790,7 +790,7 @@ Register-ArgumentCompleter -Native -CommandName 'x.py' -ScriptBlock {
         'x.py;perf' {
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--exclude', '--exclude', [CompletionResultType]::ParameterName, 'build paths to exclude')
@@ -841,7 +841,7 @@ Register-ArgumentCompleter -Native -CommandName 'x.py' -ScriptBlock {
             [CompletionResult]::new('--profiles', '--profiles', [CompletionResultType]::ParameterName, 'Select the profiles that should be benchmarked')
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--skip', '--skip', [CompletionResultType]::ParameterName, 'build paths to skip')
@@ -886,7 +886,7 @@ Register-ArgumentCompleter -Native -CommandName 'x.py' -ScriptBlock {
             [CompletionResult]::new('--profiles', '--profiles', [CompletionResultType]::ParameterName, 'Select the profiles that should be benchmarked')
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--skip', '--skip', [CompletionResultType]::ParameterName, 'build paths to skip')
@@ -931,7 +931,7 @@ Register-ArgumentCompleter -Native -CommandName 'x.py' -ScriptBlock {
             [CompletionResult]::new('--profiles', '--profiles', [CompletionResultType]::ParameterName, 'Select the profiles that should be benchmarked')
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--skip', '--skip', [CompletionResultType]::ParameterName, 'build paths to skip')
@@ -976,7 +976,7 @@ Register-ArgumentCompleter -Native -CommandName 'x.py' -ScriptBlock {
             [CompletionResult]::new('--profiles', '--profiles', [CompletionResultType]::ParameterName, 'Select the profiles that should be benchmarked')
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--skip', '--skip', [CompletionResultType]::ParameterName, 'build paths to skip')
@@ -1017,7 +1017,7 @@ Register-ArgumentCompleter -Native -CommandName 'x.py' -ScriptBlock {
         'x.py;perf;compare' {
             [CompletionResult]::new('--config', '--config', [CompletionResultType]::ParameterName, 'TOML configuration file for build')
             [CompletionResult]::new('--build-dir', '--build-dir', [CompletionResultType]::ParameterName, 'Build directory, overrides `build.build-dir` in `bootstrap.toml`')
-            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'build target of the stage0 compiler')
+            [CompletionResult]::new('--build', '--build', [CompletionResultType]::ParameterName, 'host target of the stage0 compiler')
             [CompletionResult]::new('--host', '--host', [CompletionResultType]::ParameterName, 'host targets to build')
             [CompletionResult]::new('--target', '--target', [CompletionResultType]::ParameterName, 'target targets to build')
             [CompletionResult]::new('--exclude', '--exclude', [CompletionResultType]::ParameterName, 'build paths to exclude')
diff --git a/src/etc/completions/x.py.zsh b/src/etc/completions/x.py.zsh
index bc55280d038..6dc05708199 100644
--- a/src/etc/completions/x.py.zsh
+++ b/src/etc/completions/x.py.zsh
@@ -17,7 +17,7 @@ _x.py() {
     _arguments "${_arguments_options[@]}" : \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--exclude=[build paths to exclude]:PATH:_files' \
@@ -69,7 +69,7 @@ _x.py() {
 _arguments "${_arguments_options[@]}" : \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--exclude=[build paths to exclude]:PATH:_files' \
@@ -113,7 +113,7 @@ _arguments "${_arguments_options[@]}" : \
 _arguments "${_arguments_options[@]}" : \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--exclude=[build paths to exclude]:PATH:_files' \
@@ -162,7 +162,7 @@ _arguments "${_arguments_options[@]}" : \
 '*-F+[clippy lints to forbid]:LINT:_default' \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--exclude=[build paths to exclude]:PATH:_files' \
@@ -209,7 +209,7 @@ _arguments "${_arguments_options[@]}" : \
 _arguments "${_arguments_options[@]}" : \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--exclude=[build paths to exclude]:PATH:_files' \
@@ -253,7 +253,7 @@ _arguments "${_arguments_options[@]}" : \
 _arguments "${_arguments_options[@]}" : \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--exclude=[build paths to exclude]:PATH:_files' \
@@ -299,7 +299,7 @@ _arguments "${_arguments_options[@]}" : \
 _arguments "${_arguments_options[@]}" : \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--exclude=[build paths to exclude]:PATH:_files' \
@@ -351,7 +351,7 @@ _arguments "${_arguments_options[@]}" : \
 '--run=[whether to execute run-* tests]:auto | always | never:_default' \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--exclude=[build paths to exclude]:PATH:_files' \
@@ -404,7 +404,7 @@ _arguments "${_arguments_options[@]}" : \
 '*--test-args=[extra arguments to be passed for the test tool being used (e.g. libtest, compiletest or rustdoc)]:ARGS:_default' \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--exclude=[build paths to exclude]:PATH:_files' \
@@ -452,7 +452,7 @@ _arguments "${_arguments_options[@]}" : \
 '*--test-args=[]:TEST_ARGS:_default' \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--exclude=[build paths to exclude]:PATH:_files' \
@@ -497,7 +497,7 @@ _arguments "${_arguments_options[@]}" : \
 '--stage=[Clean a specific stage without touching other artifacts. By default, every stage is cleaned if this option is not used]:N:_default' \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--exclude=[build paths to exclude]:PATH:_files' \
@@ -541,7 +541,7 @@ _arguments "${_arguments_options[@]}" : \
 _arguments "${_arguments_options[@]}" : \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--exclude=[build paths to exclude]:PATH:_files' \
@@ -585,7 +585,7 @@ _arguments "${_arguments_options[@]}" : \
 _arguments "${_arguments_options[@]}" : \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--exclude=[build paths to exclude]:PATH:_files' \
@@ -630,7 +630,7 @@ _arguments "${_arguments_options[@]}" : \
 '*--args=[arguments for the tool]:ARGS:_default' \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--exclude=[build paths to exclude]:PATH:_files' \
@@ -674,7 +674,7 @@ _arguments "${_arguments_options[@]}" : \
 _arguments "${_arguments_options[@]}" : \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--exclude=[build paths to exclude]:PATH:_files' \
@@ -719,7 +719,7 @@ _arguments "${_arguments_options[@]}" : \
 _arguments "${_arguments_options[@]}" : \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--exclude=[build paths to exclude]:PATH:_files' \
@@ -765,7 +765,7 @@ _arguments "${_arguments_options[@]}" : \
 '*--sync=[Additional \`Cargo.toml\` to sync and vendor]:SYNC:_files' \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--exclude=[build paths to exclude]:PATH:_files' \
@@ -810,7 +810,7 @@ _arguments "${_arguments_options[@]}" : \
 _arguments "${_arguments_options[@]}" : \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--exclude=[build paths to exclude]:PATH:_files' \
@@ -867,7 +867,7 @@ _arguments "${_arguments_options[@]}" : \
 '*--profiles=[Select the profiles that should be benchmarked]:PROFILES:(Check Debug Doc Opt Clippy)' \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--skip=[build paths to skip]:PATH:_files' \
@@ -914,7 +914,7 @@ _arguments "${_arguments_options[@]}" : \
 '*--profiles=[Select the profiles that should be benchmarked]:PROFILES:(Check Debug Doc Opt Clippy)' \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--skip=[build paths to skip]:PATH:_files' \
@@ -961,7 +961,7 @@ _arguments "${_arguments_options[@]}" : \
 '*--profiles=[Select the profiles that should be benchmarked]:PROFILES:(Check Debug Doc Opt Clippy)' \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--skip=[build paths to skip]:PATH:_files' \
@@ -1008,7 +1008,7 @@ _arguments "${_arguments_options[@]}" : \
 '*--profiles=[Select the profiles that should be benchmarked]:PROFILES:(Check Debug Doc Opt Clippy)' \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--skip=[build paths to skip]:PATH:_files' \
@@ -1052,7 +1052,7 @@ _arguments "${_arguments_options[@]}" : \
 _arguments "${_arguments_options[@]}" : \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--exclude=[build paths to exclude]:PATH:_files' \
diff --git a/src/etc/completions/x.zsh b/src/etc/completions/x.zsh
index 2e3094fc379..869884bf1dc 100644
--- a/src/etc/completions/x.zsh
+++ b/src/etc/completions/x.zsh
@@ -17,7 +17,7 @@ _x() {
     _arguments "${_arguments_options[@]}" : \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--exclude=[build paths to exclude]:PATH:_files' \
@@ -69,7 +69,7 @@ _x() {
 _arguments "${_arguments_options[@]}" : \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--exclude=[build paths to exclude]:PATH:_files' \
@@ -113,7 +113,7 @@ _arguments "${_arguments_options[@]}" : \
 _arguments "${_arguments_options[@]}" : \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--exclude=[build paths to exclude]:PATH:_files' \
@@ -162,7 +162,7 @@ _arguments "${_arguments_options[@]}" : \
 '*-F+[clippy lints to forbid]:LINT:_default' \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--exclude=[build paths to exclude]:PATH:_files' \
@@ -209,7 +209,7 @@ _arguments "${_arguments_options[@]}" : \
 _arguments "${_arguments_options[@]}" : \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--exclude=[build paths to exclude]:PATH:_files' \
@@ -253,7 +253,7 @@ _arguments "${_arguments_options[@]}" : \
 _arguments "${_arguments_options[@]}" : \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--exclude=[build paths to exclude]:PATH:_files' \
@@ -299,7 +299,7 @@ _arguments "${_arguments_options[@]}" : \
 _arguments "${_arguments_options[@]}" : \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--exclude=[build paths to exclude]:PATH:_files' \
@@ -351,7 +351,7 @@ _arguments "${_arguments_options[@]}" : \
 '--run=[whether to execute run-* tests]:auto | always | never:_default' \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--exclude=[build paths to exclude]:PATH:_files' \
@@ -404,7 +404,7 @@ _arguments "${_arguments_options[@]}" : \
 '*--test-args=[extra arguments to be passed for the test tool being used (e.g. libtest, compiletest or rustdoc)]:ARGS:_default' \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--exclude=[build paths to exclude]:PATH:_files' \
@@ -452,7 +452,7 @@ _arguments "${_arguments_options[@]}" : \
 '*--test-args=[]:TEST_ARGS:_default' \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--exclude=[build paths to exclude]:PATH:_files' \
@@ -497,7 +497,7 @@ _arguments "${_arguments_options[@]}" : \
 '--stage=[Clean a specific stage without touching other artifacts. By default, every stage is cleaned if this option is not used]:N:_default' \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--exclude=[build paths to exclude]:PATH:_files' \
@@ -541,7 +541,7 @@ _arguments "${_arguments_options[@]}" : \
 _arguments "${_arguments_options[@]}" : \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--exclude=[build paths to exclude]:PATH:_files' \
@@ -585,7 +585,7 @@ _arguments "${_arguments_options[@]}" : \
 _arguments "${_arguments_options[@]}" : \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--exclude=[build paths to exclude]:PATH:_files' \
@@ -630,7 +630,7 @@ _arguments "${_arguments_options[@]}" : \
 '*--args=[arguments for the tool]:ARGS:_default' \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--exclude=[build paths to exclude]:PATH:_files' \
@@ -674,7 +674,7 @@ _arguments "${_arguments_options[@]}" : \
 _arguments "${_arguments_options[@]}" : \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--exclude=[build paths to exclude]:PATH:_files' \
@@ -719,7 +719,7 @@ _arguments "${_arguments_options[@]}" : \
 _arguments "${_arguments_options[@]}" : \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--exclude=[build paths to exclude]:PATH:_files' \
@@ -765,7 +765,7 @@ _arguments "${_arguments_options[@]}" : \
 '*--sync=[Additional \`Cargo.toml\` to sync and vendor]:SYNC:_files' \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--exclude=[build paths to exclude]:PATH:_files' \
@@ -810,7 +810,7 @@ _arguments "${_arguments_options[@]}" : \
 _arguments "${_arguments_options[@]}" : \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--exclude=[build paths to exclude]:PATH:_files' \
@@ -867,7 +867,7 @@ _arguments "${_arguments_options[@]}" : \
 '*--profiles=[Select the profiles that should be benchmarked]:PROFILES:(Check Debug Doc Opt Clippy)' \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--skip=[build paths to skip]:PATH:_files' \
@@ -914,7 +914,7 @@ _arguments "${_arguments_options[@]}" : \
 '*--profiles=[Select the profiles that should be benchmarked]:PROFILES:(Check Debug Doc Opt Clippy)' \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--skip=[build paths to skip]:PATH:_files' \
@@ -961,7 +961,7 @@ _arguments "${_arguments_options[@]}" : \
 '*--profiles=[Select the profiles that should be benchmarked]:PROFILES:(Check Debug Doc Opt Clippy)' \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--skip=[build paths to skip]:PATH:_files' \
@@ -1008,7 +1008,7 @@ _arguments "${_arguments_options[@]}" : \
 '*--profiles=[Select the profiles that should be benchmarked]:PROFILES:(Check Debug Doc Opt Clippy)' \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--skip=[build paths to skip]:PATH:_files' \
@@ -1052,7 +1052,7 @@ _arguments "${_arguments_options[@]}" : \
 _arguments "${_arguments_options[@]}" : \
 '--config=[TOML configuration file for build]:FILE:_files' \
 '--build-dir=[Build directory, overrides \`build.build-dir\` in \`bootstrap.toml\`]:DIR:_files -/' \
-'--build=[build target of the stage0 compiler]:BUILD:' \
+'--build=[host target of the stage0 compiler]:BUILD:' \
 '--host=[host targets to build]:HOST:' \
 '--target=[target targets to build]:TARGET:' \
 '*--exclude=[build paths to exclude]:PATH:_files' \
diff --git a/src/librustdoc/clean/auto_trait.rs b/src/librustdoc/clean/auto_trait.rs
index 138ac3c97f7..a91ea55bcae 100644
--- a/src/librustdoc/clean/auto_trait.rs
+++ b/src/librustdoc/clean/auto_trait.rs
@@ -11,7 +11,7 @@ use tracing::{debug, instrument};
 
 use crate::clean::{
     self, Lifetime, clean_generic_param_def, clean_middle_ty, clean_predicate,
-    clean_trait_ref_with_constraints, clean_ty_generics, simplify,
+    clean_trait_ref_with_constraints, clean_ty_generics_inner, simplify,
 };
 use crate::core::DocContext;
 
@@ -101,7 +101,7 @@ fn synthesize_auto_trait_impl<'tcx>(
             // Instead, we generate `impl !Send for Foo<T>`, which better
             // expresses the fact that `Foo<T>` never implements `Send`,
             // regardless of the choice of `T`.
-            let mut generics = clean_ty_generics(
+            let mut generics = clean_ty_generics_inner(
                 cx,
                 tcx.generics_of(item_def_id),
                 ty::GenericPredicates::default(),
diff --git a/src/librustdoc/clean/blanket_impl.rs b/src/librustdoc/clean/blanket_impl.rs
index 89245fee515..c889f52b789 100644
--- a/src/librustdoc/clean/blanket_impl.rs
+++ b/src/librustdoc/clean/blanket_impl.rs
@@ -90,11 +90,7 @@ pub(crate) fn synthesize_blanket_impls(
                     stability: None,
                     kind: clean::ImplItem(Box::new(clean::Impl {
                         safety: hir::Safety::Safe,
-                        generics: clean_ty_generics(
-                            cx,
-                            tcx.generics_of(impl_def_id),
-                            tcx.explicit_predicates_of(impl_def_id),
-                        ),
+                        generics: clean_ty_generics(cx, impl_def_id),
                         // FIXME(eddyb) compute both `trait_` and `for_` from
                         // the post-inference `trait_ref`, as it's more accurate.
                         trait_: Some(clean_trait_ref_with_constraints(
diff --git a/src/librustdoc/clean/cfg.rs b/src/librustdoc/clean/cfg.rs
index a3762e4117d..b6ce8551060 100644
--- a/src/librustdoc/clean/cfg.rs
+++ b/src/librustdoc/clean/cfg.rs
@@ -169,33 +169,36 @@ impl Cfg {
         msg
     }
 
-    /// Renders the configuration for long display, as a long HTML description.
-    pub(crate) fn render_long_html(&self) -> String {
+    fn render_long_inner(&self, format: Format) -> String {
         let on = if self.omit_preposition() {
-            ""
+            " "
         } else if self.should_use_with_in_description() {
-            "with "
+            " with "
         } else {
-            "on "
+            " on "
         };
 
-        let mut msg = format!("Available {on}<strong>{}</strong>", Display(self, Format::LongHtml));
+        let mut msg = if matches!(format, Format::LongHtml) {
+            format!("Available{on}<strong>{}</strong>", Display(self, format))
+        } else {
+            format!("Available{on}{}", Display(self, format))
+        };
         if self.should_append_only_to_description() {
             msg.push_str(" only");
         }
+        msg
+    }
+
+    /// Renders the configuration for long display, as a long HTML description.
+    pub(crate) fn render_long_html(&self) -> String {
+        let mut msg = self.render_long_inner(Format::LongHtml);
         msg.push('.');
         msg
     }
 
     /// Renders the configuration for long display, as a long plain text description.
     pub(crate) fn render_long_plain(&self) -> String {
-        let on = if self.should_use_with_in_description() { "with" } else { "on" };
-
-        let mut msg = format!("Available {on} {}", Display(self, Format::LongPlain));
-        if self.should_append_only_to_description() {
-            msg.push_str(" only");
-        }
-        msg
+        self.render_long_inner(Format::LongPlain)
     }
 
     fn should_capitalize_first_letter(&self) -> bool {
diff --git a/src/librustdoc/clean/inline.rs b/src/librustdoc/clean/inline.rs
index 55a116a018a..dcd499d5f0d 100644
--- a/src/librustdoc/clean/inline.rs
+++ b/src/librustdoc/clean/inline.rs
@@ -264,25 +264,35 @@ pub(crate) fn build_trait(cx: &mut DocContext<'_>, did: DefId) -> clean::Trait {
         .map(|item| clean_middle_assoc_item(item, cx))
         .collect();
 
-    let predicates = cx.tcx.predicates_of(did);
-    let generics = clean_ty_generics(cx, cx.tcx.generics_of(did), predicates);
-    let generics = filter_non_trait_generics(did, generics);
-    let (generics, supertrait_bounds) = separate_self_bounds(generics);
+    let generics = clean_ty_generics(cx, did);
+    let (generics, mut supertrait_bounds) = separate_self_bounds(generics);
+
+    supertrait_bounds.retain(|b| {
+        // FIXME(sized-hierarchy): Always skip `MetaSized` bounds so that only `?Sized`
+        // is shown and none of the new sizedness traits leak into documentation.
+        !b.is_meta_sized_bound(cx)
+    });
+
     clean::Trait { def_id: did, generics, items: trait_items, bounds: supertrait_bounds }
 }
 
 fn build_trait_alias(cx: &mut DocContext<'_>, did: DefId) -> clean::TraitAlias {
-    let predicates = cx.tcx.predicates_of(did);
-    let generics = clean_ty_generics(cx, cx.tcx.generics_of(did), predicates);
-    let (generics, bounds) = separate_self_bounds(generics);
+    let generics = clean_ty_generics(cx, did);
+    let (generics, mut bounds) = separate_self_bounds(generics);
+
+    bounds.retain(|b| {
+        // FIXME(sized-hierarchy): Always skip `MetaSized` bounds so that only `?Sized`
+        // is shown and none of the new sizedness traits leak into documentation.
+        !b.is_meta_sized_bound(cx)
+    });
+
     clean::TraitAlias { generics, bounds }
 }
 
 pub(super) fn build_function(cx: &mut DocContext<'_>, def_id: DefId) -> Box<clean::Function> {
     let sig = cx.tcx.fn_sig(def_id).instantiate_identity();
     // The generics need to be cleaned before the signature.
-    let mut generics =
-        clean_ty_generics(cx, cx.tcx.generics_of(def_id), cx.tcx.explicit_predicates_of(def_id));
+    let mut generics = clean_ty_generics(cx, def_id);
     let bound_vars = clean_bound_vars(sig.bound_vars());
 
     // At the time of writing early & late-bound params are stored separately in rustc,
@@ -311,30 +321,26 @@ pub(super) fn build_function(cx: &mut DocContext<'_>, def_id: DefId) -> Box<clea
 }
 
 fn build_enum(cx: &mut DocContext<'_>, did: DefId) -> clean::Enum {
-    let predicates = cx.tcx.explicit_predicates_of(did);
-
     clean::Enum {
-        generics: clean_ty_generics(cx, cx.tcx.generics_of(did), predicates),
+        generics: clean_ty_generics(cx, did),
         variants: cx.tcx.adt_def(did).variants().iter().map(|v| clean_variant_def(v, cx)).collect(),
     }
 }
 
 fn build_struct(cx: &mut DocContext<'_>, did: DefId) -> clean::Struct {
-    let predicates = cx.tcx.explicit_predicates_of(did);
     let variant = cx.tcx.adt_def(did).non_enum_variant();
 
     clean::Struct {
         ctor_kind: variant.ctor_kind(),
-        generics: clean_ty_generics(cx, cx.tcx.generics_of(did), predicates),
+        generics: clean_ty_generics(cx, did),
         fields: variant.fields.iter().map(|x| clean_middle_field(x, cx)).collect(),
     }
 }
 
 fn build_union(cx: &mut DocContext<'_>, did: DefId) -> clean::Union {
-    let predicates = cx.tcx.explicit_predicates_of(did);
     let variant = cx.tcx.adt_def(did).non_enum_variant();
 
-    let generics = clean_ty_generics(cx, cx.tcx.generics_of(did), predicates);
+    let generics = clean_ty_generics(cx, did);
     let fields = variant.fields.iter().map(|x| clean_middle_field(x, cx)).collect();
     clean::Union { generics, fields }
 }
@@ -344,14 +350,13 @@ fn build_type_alias(
     did: DefId,
     ret: &mut Vec<Item>,
 ) -> Box<clean::TypeAlias> {
-    let predicates = cx.tcx.explicit_predicates_of(did);
     let ty = cx.tcx.type_of(did).instantiate_identity();
     let type_ = clean_middle_ty(ty::Binder::dummy(ty), cx, Some(did), None);
     let inner_type = clean_ty_alias_inner_type(ty, cx, ret);
 
     Box::new(clean::TypeAlias {
         type_,
-        generics: clean_ty_generics(cx, cx.tcx.generics_of(did), predicates),
+        generics: clean_ty_generics(cx, did),
         inner_type,
         item_type: None,
     })
@@ -483,7 +488,6 @@ pub(crate) fn build_impl(
     }
 
     let document_hidden = cx.render_options.document_hidden;
-    let predicates = tcx.explicit_predicates_of(did);
     let (trait_items, generics) = match impl_item {
         Some(impl_) => (
             impl_
@@ -549,9 +553,7 @@ pub(crate) fn build_impl(
                 })
                 .map(|item| clean_middle_assoc_item(item, cx))
                 .collect::<Vec<_>>(),
-            clean::enter_impl_trait(cx, |cx| {
-                clean_ty_generics(cx, tcx.generics_of(did), predicates)
-            }),
+            clean::enter_impl_trait(cx, |cx| clean_ty_generics(cx, did)),
         ),
     };
     let polarity = tcx.impl_polarity(did);
@@ -713,8 +715,7 @@ pub(crate) fn print_inlined_const(tcx: TyCtxt<'_>, did: DefId) -> String {
 }
 
 fn build_const_item(cx: &mut DocContext<'_>, def_id: DefId) -> clean::Constant {
-    let mut generics =
-        clean_ty_generics(cx, cx.tcx.generics_of(def_id), cx.tcx.explicit_predicates_of(def_id));
+    let mut generics = clean_ty_generics(cx, def_id);
     clean::simplify::move_bounds_to_generic_parameters(&mut generics);
     let ty = clean_middle_ty(
         ty::Binder::dummy(cx.tcx.type_of(def_id).instantiate_identity()),
@@ -761,44 +762,6 @@ fn build_macro(
     }
 }
 
-/// A trait's generics clause actually contains all of the predicates for all of
-/// its associated types as well. We specifically move these clauses to the
-/// associated types instead when displaying, so when we're generating the
-/// generics for the trait itself we need to be sure to remove them.
-/// We also need to remove the implied "recursive" Self: Trait bound.
-///
-/// The inverse of this filtering logic can be found in the `Clean`
-/// implementation for `AssociatedType`
-fn filter_non_trait_generics(trait_did: DefId, mut g: clean::Generics) -> clean::Generics {
-    for pred in &mut g.where_predicates {
-        if let clean::WherePredicate::BoundPredicate { ty: clean::SelfTy, ref mut bounds, .. } =
-            *pred
-        {
-            bounds.retain(|bound| match bound {
-                clean::GenericBound::TraitBound(clean::PolyTrait { trait_, .. }, _) => {
-                    trait_.def_id() != trait_did
-                }
-                _ => true,
-            });
-        }
-    }
-
-    g.where_predicates.retain(|pred| match pred {
-        clean::WherePredicate::BoundPredicate {
-            ty:
-                clean::QPath(box clean::QPathData {
-                    self_type: clean::Generic(_),
-                    trait_: Some(trait_),
-                    ..
-                }),
-            bounds,
-            ..
-        } => !bounds.is_empty() && trait_.def_id() != trait_did,
-        _ => true,
-    });
-    g
-}
-
 fn separate_self_bounds(mut g: clean::Generics) -> (clean::Generics, Vec<clean::GenericBound>) {
     let mut ty_bounds = Vec::new();
     g.where_predicates.retain(|pred| match *pred {
diff --git a/src/librustdoc/clean/mod.rs b/src/librustdoc/clean/mod.rs
index 7658e7ad35f..d77bdf09d01 100644
--- a/src/librustdoc/clean/mod.rs
+++ b/src/librustdoc/clean/mod.rs
@@ -39,9 +39,9 @@ use rustc_ast::tokenstream::{TokenStream, TokenTree};
 use rustc_data_structures::fx::{FxHashMap, FxHashSet, FxIndexMap, FxIndexSet, IndexEntry};
 use rustc_errors::codes::*;
 use rustc_errors::{FatalError, struct_span_code_err};
-use rustc_hir::PredicateOrigin;
 use rustc_hir::def::{CtorKind, DefKind, Res};
 use rustc_hir::def_id::{DefId, DefIdMap, DefIdSet, LOCAL_CRATE, LocalDefId};
+use rustc_hir::{LangItem, PredicateOrigin};
 use rustc_hir_analysis::hir_ty_lowering::FeedConstTy;
 use rustc_hir_analysis::{lower_const_arg_for_rustdoc, lower_ty};
 use rustc_middle::metadata::Reexport;
@@ -793,7 +793,11 @@ pub(crate) fn clean_generics<'tcx>(
     }
 }
 
-fn clean_ty_generics<'tcx>(
+fn clean_ty_generics<'tcx>(cx: &mut DocContext<'tcx>, def_id: DefId) -> Generics {
+    clean_ty_generics_inner(cx, cx.tcx.generics_of(def_id), cx.tcx.explicit_predicates_of(def_id))
+}
+
+fn clean_ty_generics_inner<'tcx>(
     cx: &mut DocContext<'tcx>,
     gens: &ty::Generics,
     preds: ty::GenericPredicates<'tcx>,
@@ -882,6 +886,10 @@ fn clean_ty_generics<'tcx>(
             if b.is_sized_bound(cx) {
                 has_sized = true;
                 false
+            } else if b.is_meta_sized_bound(cx) {
+                // FIXME(sized-hierarchy): Always skip `MetaSized` bounds so that only `?Sized`
+                // is shown and none of the new sizedness traits leak into documentation.
+                false
             } else {
                 true
             }
@@ -1297,11 +1305,7 @@ pub(crate) fn clean_middle_assoc_item(assoc_item: &ty::AssocItem, cx: &mut DocCo
                 None,
             );
 
-            let mut generics = clean_ty_generics(
-                cx,
-                tcx.generics_of(assoc_item.def_id),
-                tcx.explicit_predicates_of(assoc_item.def_id),
-            );
+            let mut generics = clean_ty_generics(cx, assoc_item.def_id);
             simplify::move_bounds_to_generic_parameters(&mut generics);
 
             match assoc_item.container {
@@ -1389,7 +1393,7 @@ pub(crate) fn clean_middle_assoc_item(assoc_item: &ty::AssocItem, cx: &mut DocCo
                 let bounds = tcx.explicit_item_bounds(assoc_item.def_id).iter_identity_copied();
                 predicates = tcx.arena.alloc_from_iter(bounds.chain(predicates.iter().copied()));
             }
-            let mut generics = clean_ty_generics(
+            let mut generics = clean_ty_generics_inner(
                 cx,
                 tcx.generics_of(assoc_item.def_id),
                 ty::GenericPredicates { parent: None, predicates },
@@ -1448,6 +1452,13 @@ pub(crate) fn clean_middle_assoc_item(assoc_item: &ty::AssocItem, cx: &mut DocCo
                     }
                     _ => true,
                 });
+
+                bounds.retain(|b| {
+                    // FIXME(sized-hierarchy): Always skip `MetaSized` bounds so that only `?Sized`
+                    // is shown and none of the new sizedness traits leak into documentation.
+                    !b.is_meta_sized_bound(cx)
+                });
+
                 // Our Sized/?Sized bound didn't get handled when creating the generics
                 // because we didn't actually get our whole set of bounds until just now
                 // (some of them may have come from the trait). If we do have a sized
@@ -2276,6 +2287,12 @@ fn clean_middle_opaque_bounds<'tcx>(
                 _ => return None,
             };
 
+            // FIXME(sized-hierarchy): Always skip `MetaSized` bounds so that only `?Sized`
+            // is shown and none of the new sizedness traits leak into documentation.
+            if cx.tcx.is_lang_item(trait_ref.def_id(), LangItem::MetaSized) {
+                return None;
+            }
+
             if let Some(sized) = cx.tcx.lang_items().sized_trait()
                 && trait_ref.def_id() == sized
             {
diff --git a/src/librustdoc/clean/simplify.rs b/src/librustdoc/clean/simplify.rs
index 40efa997868..f813e6c5517 100644
--- a/src/librustdoc/clean/simplify.rs
+++ b/src/librustdoc/clean/simplify.rs
@@ -135,11 +135,17 @@ pub(crate) fn sized_bounds(cx: &mut DocContext<'_>, generics: &mut clean::Generi
     // don't actually know the set of associated types right here so that
     // should be handled when cleaning associated types.
     generics.where_predicates.retain(|pred| {
-        if let WP::BoundPredicate { ty: clean::Generic(param), bounds, .. } = pred
-            && bounds.iter().any(|b| b.is_sized_bound(cx))
-        {
+        let WP::BoundPredicate { ty: clean::Generic(param), bounds, .. } = pred else {
+            return true;
+        };
+
+        if bounds.iter().any(|b| b.is_sized_bound(cx)) {
             sized_params.insert(*param);
             false
+        } else if bounds.iter().any(|b| b.is_meta_sized_bound(cx)) {
+            // FIXME(sized-hierarchy): Always skip `MetaSized` bounds so that only `?Sized`
+            // is shown and none of the new sizedness traits leak into documentation.
+            false
         } else {
             true
         }
diff --git a/src/librustdoc/clean/types.rs b/src/librustdoc/clean/types.rs
index bde1a2e5e66..2d9670a3d10 100644
--- a/src/librustdoc/clean/types.rs
+++ b/src/librustdoc/clean/types.rs
@@ -1289,11 +1289,19 @@ impl GenericBound {
     }
 
     pub(crate) fn is_sized_bound(&self, cx: &DocContext<'_>) -> bool {
+        self.is_bounded_by_lang_item(cx, LangItem::Sized)
+    }
+
+    pub(crate) fn is_meta_sized_bound(&self, cx: &DocContext<'_>) -> bool {
+        self.is_bounded_by_lang_item(cx, LangItem::MetaSized)
+    }
+
+    fn is_bounded_by_lang_item(&self, cx: &DocContext<'_>, lang_item: LangItem) -> bool {
         if let GenericBound::TraitBound(
             PolyTrait { ref trait_, .. },
             rustc_hir::TraitBoundModifiers::NONE,
         ) = *self
-            && Some(trait_.def_id()) == cx.tcx.lang_items().sized_trait()
+            && cx.tcx.is_lang_item(trait_.def_id(), lang_item)
         {
             return true;
         }
@@ -2638,7 +2646,7 @@ mod size_asserts {
     static_assert_size!(GenericParamDef, 40);
     static_assert_size!(Generics, 16);
     static_assert_size!(Item, 8);
-    static_assert_size!(ItemInner, 136);
+    static_assert_size!(ItemInner, 144);
     static_assert_size!(ItemKind, 48);
     static_assert_size!(PathSegment, 32);
     static_assert_size!(Type, 32);
diff --git a/src/librustdoc/doctest.rs b/src/librustdoc/doctest.rs
index a81d6020f71..130fdff1afe 100644
--- a/src/librustdoc/doctest.rs
+++ b/src/librustdoc/doctest.rs
@@ -1053,14 +1053,14 @@ fn doctest_run_fn(
     let report_unused_externs = |uext| {
         unused_externs.lock().unwrap().push(uext);
     };
-    let (full_test_code, full_test_line_offset) = doctest.generate_unique_doctest(
+    let (wrapped, full_test_line_offset) = doctest.generate_unique_doctest(
         &scraped_test.text,
         scraped_test.langstr.test_harness,
         &global_opts,
         Some(&global_opts.crate_name),
     );
     let runnable_test = RunnableDocTest {
-        full_test_code,
+        full_test_code: wrapped.to_string(),
         full_test_line_offset,
         test_opts,
         global_opts,
diff --git a/src/librustdoc/doctest/extracted.rs b/src/librustdoc/doctest/extracted.rs
index ebe6bfd22ba..925fb6fee2c 100644
--- a/src/librustdoc/doctest/extracted.rs
+++ b/src/librustdoc/doctest/extracted.rs
@@ -3,8 +3,10 @@
 //! This module contains the logic to extract doctests and output a JSON containing this
 //! information.
 
+use rustc_span::edition::Edition;
 use serde::Serialize;
 
+use super::make::DocTestWrapResult;
 use super::{BuildDocTestBuilder, ScrapedDocTest};
 use crate::config::Options as RustdocOptions;
 use crate::html::markdown;
@@ -14,7 +16,7 @@ use crate::html::markdown;
 /// This integer is incremented with every breaking change to the API,
 /// and is returned along with the JSON blob into the `format_version` root field.
 /// Consuming code should assert that this value matches the format version(s) that it supports.
-const FORMAT_VERSION: u32 = 1;
+const FORMAT_VERSION: u32 = 2;
 
 #[derive(Serialize)]
 pub(crate) struct ExtractedDocTests {
@@ -34,7 +36,16 @@ impl ExtractedDocTests {
         options: &RustdocOptions,
     ) {
         let edition = scraped_test.edition(options);
+        self.add_test_with_edition(scraped_test, opts, edition)
+    }
 
+    /// This method is used by unit tests to not have to provide a `RustdocOptions`.
+    pub(crate) fn add_test_with_edition(
+        &mut self,
+        scraped_test: ScrapedDocTest,
+        opts: &super::GlobalTestOptions,
+        edition: Edition,
+    ) {
         let ScrapedDocTest { filename, line, langstr, text, name, global_crate_attrs, .. } =
             scraped_test;
 
@@ -44,8 +55,7 @@ impl ExtractedDocTests {
             .edition(edition)
             .lang_str(&langstr)
             .build(None);
-
-        let (full_test_code, size) = doctest.generate_unique_doctest(
+        let (wrapped, _size) = doctest.generate_unique_doctest(
             &text,
             langstr.test_harness,
             opts,
@@ -55,11 +65,46 @@ impl ExtractedDocTests {
             file: filename.prefer_remapped_unconditionaly().to_string(),
             line,
             doctest_attributes: langstr.into(),
-            doctest_code: if size != 0 { Some(full_test_code) } else { None },
+            doctest_code: match wrapped {
+                DocTestWrapResult::Valid { crate_level_code, wrapper, code } => Some(DocTest {
+                    crate_level: crate_level_code,
+                    code,
+                    wrapper: wrapper.map(
+                        |super::make::WrapperInfo { before, after, returns_result, .. }| {
+                            WrapperInfo { before, after, returns_result }
+                        },
+                    ),
+                }),
+                DocTestWrapResult::SyntaxError { .. } => None,
+            },
             original_code: text,
             name,
         });
     }
+
+    #[cfg(test)]
+    pub(crate) fn doctests(&self) -> &[ExtractedDocTest] {
+        &self.doctests
+    }
+}
+
+#[derive(Serialize)]
+pub(crate) struct WrapperInfo {
+    before: String,
+    after: String,
+    returns_result: bool,
+}
+
+#[derive(Serialize)]
+pub(crate) struct DocTest {
+    crate_level: String,
+    code: String,
+    /// This field can be `None` if one of the following conditions is true:
+    ///
+    /// * The doctest's codeblock has the `test_harness` attribute.
+    /// * The doctest has a `main` function.
+    /// * The doctest has the `![no_std]` attribute.
+    pub(crate) wrapper: Option<WrapperInfo>,
 }
 
 #[derive(Serialize)]
@@ -69,7 +114,7 @@ pub(crate) struct ExtractedDocTest {
     doctest_attributes: LangString,
     original_code: String,
     /// `None` if the code syntax is invalid.
-    doctest_code: Option<String>,
+    pub(crate) doctest_code: Option<DocTest>,
     name: String,
 }
 
diff --git a/src/librustdoc/doctest/make.rs b/src/librustdoc/doctest/make.rs
index 5e571613d6f..3ff6828e52f 100644
--- a/src/librustdoc/doctest/make.rs
+++ b/src/librustdoc/doctest/make.rs
@@ -196,6 +196,80 @@ pub(crate) struct DocTestBuilder {
     pub(crate) can_be_merged: bool,
 }
 
+/// Contains needed information for doctest to be correctly generated with expected "wrapping".
+pub(crate) struct WrapperInfo {
+    pub(crate) before: String,
+    pub(crate) after: String,
+    pub(crate) returns_result: bool,
+    insert_indent_space: bool,
+}
+
+impl WrapperInfo {
+    fn len(&self) -> usize {
+        self.before.len() + self.after.len()
+    }
+}
+
+/// Contains a doctest information. Can be converted into code with the `to_string()` method.
+pub(crate) enum DocTestWrapResult {
+    Valid {
+        crate_level_code: String,
+        /// This field can be `None` if one of the following conditions is true:
+        ///
+        /// * The doctest's codeblock has the `test_harness` attribute.
+        /// * The doctest has a `main` function.
+        /// * The doctest has the `![no_std]` attribute.
+        wrapper: Option<WrapperInfo>,
+        /// Contains the doctest processed code without the wrappers (which are stored in the
+        /// `wrapper` field).
+        code: String,
+    },
+    /// Contains the original source code.
+    SyntaxError(String),
+}
+
+impl std::string::ToString for DocTestWrapResult {
+    fn to_string(&self) -> String {
+        match self {
+            Self::SyntaxError(s) => s.clone(),
+            Self::Valid { crate_level_code, wrapper, code } => {
+                let mut prog_len = code.len() + crate_level_code.len();
+                if let Some(wrapper) = wrapper {
+                    prog_len += wrapper.len();
+                    if wrapper.insert_indent_space {
+                        prog_len += code.lines().count() * 4;
+                    }
+                }
+                let mut prog = String::with_capacity(prog_len);
+
+                prog.push_str(crate_level_code);
+                if let Some(wrapper) = wrapper {
+                    prog.push_str(&wrapper.before);
+
+                    // add extra 4 spaces for each line to offset the code block
+                    if wrapper.insert_indent_space {
+                        write!(
+                            prog,
+                            "{}",
+                            fmt::from_fn(|f| code
+                                .lines()
+                                .map(|line| fmt::from_fn(move |f| write!(f, "    {line}")))
+                                .joined("\n", f))
+                        )
+                        .unwrap();
+                    } else {
+                        prog.push_str(code);
+                    }
+                    prog.push_str(&wrapper.after);
+                } else {
+                    prog.push_str(code);
+                }
+                prog
+            }
+        }
+    }
+}
+
 impl DocTestBuilder {
     fn invalid(
         global_crate_attrs: Vec<String>,
@@ -228,50 +302,49 @@ impl DocTestBuilder {
         dont_insert_main: bool,
         opts: &GlobalTestOptions,
         crate_name: Option<&str>,
-    ) -> (String, usize) {
+    ) -> (DocTestWrapResult, usize) {
         if self.invalid_ast {
             // If the AST failed to compile, no need to go generate a complete doctest, the error
             // will be better this way.
             debug!("invalid AST:\n{test_code}");
-            return (test_code.to_string(), 0);
+            return (DocTestWrapResult::SyntaxError(test_code.to_string()), 0);
         }
         let mut line_offset = 0;
-        let mut prog = String::new();
-        let everything_else = self.everything_else.trim();
-
+        let mut crate_level_code = String::new();
+        let processed_code = self.everything_else.trim();
         if self.global_crate_attrs.is_empty() {
             // If there aren't any attributes supplied by #![doc(test(attr(...)))], then allow some
             // lints that are commonly triggered in doctests. The crate-level test attributes are
             // commonly used to make tests fail in case they trigger warnings, so having this there in
             // that case may cause some tests to pass when they shouldn't have.
-            prog.push_str("#![allow(unused)]\n");
+            crate_level_code.push_str("#![allow(unused)]\n");
             line_offset += 1;
         }
 
         // Next, any attributes that came from #![doc(test(attr(...)))].
         for attr in &self.global_crate_attrs {
-            prog.push_str(&format!("#![{attr}]\n"));
+            crate_level_code.push_str(&format!("#![{attr}]\n"));
             line_offset += 1;
         }
 
         // Now push any outer attributes from the example, assuming they
         // are intended to be crate attributes.
         if !self.crate_attrs.is_empty() {
-            prog.push_str(&self.crate_attrs);
+            crate_level_code.push_str(&self.crate_attrs);
             if !self.crate_attrs.ends_with('\n') {
-                prog.push('\n');
+                crate_level_code.push('\n');
             }
         }
         if !self.maybe_crate_attrs.is_empty() {
-            prog.push_str(&self.maybe_crate_attrs);
+            crate_level_code.push_str(&self.maybe_crate_attrs);
             if !self.maybe_crate_attrs.ends_with('\n') {
-                prog.push('\n');
+                crate_level_code.push('\n');
             }
         }
         if !self.crates.is_empty() {
-            prog.push_str(&self.crates);
+            crate_level_code.push_str(&self.crates);
             if !self.crates.ends_with('\n') {
-                prog.push('\n');
+                crate_level_code.push('\n');
             }
         }
 
@@ -289,17 +362,20 @@ impl DocTestBuilder {
         {
             // rustdoc implicitly inserts an `extern crate` item for the own crate
             // which may be unused, so we need to allow the lint.
-            prog.push_str("#[allow(unused_extern_crates)]\n");
+            crate_level_code.push_str("#[allow(unused_extern_crates)]\n");
 
-            prog.push_str(&format!("extern crate r#{crate_name};\n"));
+            crate_level_code.push_str(&format!("extern crate r#{crate_name};\n"));
             line_offset += 1;
         }
 
         // FIXME: This code cannot yet handle no_std test cases yet
-        if dont_insert_main || self.has_main_fn || prog.contains("![no_std]") {
-            prog.push_str(everything_else);
+        let wrapper = if dont_insert_main
+            || self.has_main_fn
+            || crate_level_code.contains("![no_std]")
+        {
+            None
         } else {
-            let returns_result = everything_else.ends_with("(())");
+            let returns_result = processed_code.ends_with("(())");
             // Give each doctest main function a unique name.
             // This is for example needed for the tooling around `-C instrument-coverage`.
             let inner_fn_name = if let Some(ref test_id) = self.test_id {
@@ -333,28 +409,22 @@ impl DocTestBuilder {
             // /// ``` <- end of the inner main
             line_offset += 1;
 
-            prog.push_str(&main_pre);
-
-            // add extra 4 spaces for each line to offset the code block
-            if opts.insert_indent_space {
-                write!(
-                    prog,
-                    "{}",
-                    fmt::from_fn(|f| everything_else
-                        .lines()
-                        .map(|line| fmt::from_fn(move |f| write!(f, "    {line}")))
-                        .joined("\n", f))
-                )
-                .unwrap();
-            } else {
-                prog.push_str(everything_else);
-            };
-            prog.push_str(&main_post);
-        }
-
-        debug!("final doctest:\n{prog}");
+            Some(WrapperInfo {
+                before: main_pre,
+                after: main_post,
+                returns_result,
+                insert_indent_space: opts.insert_indent_space,
+            })
+        };
 
-        (prog, line_offset)
+        (
+            DocTestWrapResult::Valid {
+                code: processed_code.to_string(),
+                wrapper,
+                crate_level_code,
+            },
+            line_offset,
+        )
     }
 }
 
diff --git a/src/librustdoc/doctest/tests.rs b/src/librustdoc/doctest/tests.rs
index ce2984ced79..ccc3e55a331 100644
--- a/src/librustdoc/doctest/tests.rs
+++ b/src/librustdoc/doctest/tests.rs
@@ -1,6 +1,11 @@
 use std::path::PathBuf;
 
-use super::{BuildDocTestBuilder, GlobalTestOptions};
+use rustc_span::edition::Edition;
+use rustc_span::{DUMMY_SP, FileName};
+
+use super::extracted::ExtractedDocTests;
+use super::{BuildDocTestBuilder, GlobalTestOptions, ScrapedDocTest};
+use crate::html::markdown::LangString;
 
 fn make_test(
     test_code: &str,
@@ -19,9 +24,9 @@ fn make_test(
         builder = builder.test_id(test_id.to_string());
     }
     let doctest = builder.build(None);
-    let (code, line_offset) =
+    let (wrapped, line_offset) =
         doctest.generate_unique_doctest(test_code, dont_insert_main, opts, crate_name);
-    (code, line_offset)
+    (wrapped.to_string(), line_offset)
 }
 
 /// Default [`GlobalTestOptions`] for these unit tests.
@@ -461,3 +466,51 @@ pub mod outer_module {
     let (output, len) = make_test(input, None, false, &opts, Vec::new(), None);
     assert_eq!((output, len), (expected, 2));
 }
+
+fn get_extracted_doctests(code: &str) -> ExtractedDocTests {
+    let opts = default_global_opts("");
+    let mut extractor = ExtractedDocTests::new();
+    extractor.add_test_with_edition(
+        ScrapedDocTest::new(
+            FileName::Custom(String::new()),
+            0,
+            Vec::new(),
+            LangString::default(),
+            code.to_string(),
+            DUMMY_SP,
+            Vec::new(),
+        ),
+        &opts,
+        Edition::Edition2018,
+    );
+    extractor
+}
+
+// Test that `extracted::DocTest::wrapper` is `None` if the doctest has a `main` function.
+#[test]
+fn test_extracted_doctest_wrapper_field() {
+    let extractor = get_extracted_doctests("fn main() {}");
+
+    assert_eq!(extractor.doctests().len(), 1);
+    let doctest_code = extractor.doctests()[0].doctest_code.as_ref().unwrap();
+    assert!(doctest_code.wrapper.is_none());
+}
+
+// Test that `ExtractedDocTest::doctest_code` is `None` if the doctest has syntax error.
+#[test]
+fn test_extracted_doctest_doctest_code_field() {
+    let extractor = get_extracted_doctests("let x +=");
+
+    assert_eq!(extractor.doctests().len(), 1);
+    assert!(extractor.doctests()[0].doctest_code.is_none());
+}
+
+// Test that `extracted::DocTest::wrapper` is `Some` if the doctest needs wrapping.
+#[test]
+fn test_extracted_doctest_wrapper_field_with_info() {
+    let extractor = get_extracted_doctests("let x = 12;");
+
+    assert_eq!(extractor.doctests().len(), 1);
+    let doctest_code = extractor.doctests()[0].doctest_code.as_ref().unwrap();
+    assert!(doctest_code.wrapper.is_some());
+}
diff --git a/src/librustdoc/formats/renderer.rs b/src/librustdoc/formats/renderer.rs
index 5e4e6f27a15..48626171404 100644
--- a/src/librustdoc/formats/renderer.rs
+++ b/src/librustdoc/formats/renderer.rs
@@ -56,7 +56,7 @@ pub(crate) trait FormatRenderer<'tcx>: Sized {
     fn restore_module_data(&mut self, info: Self::ModuleData);
 
     /// Renders a single non-module item. This means no recursive sub-item rendering is required.
-    fn item(&mut self, item: clean::Item) -> Result<(), Error>;
+    fn item(&mut self, item: &clean::Item) -> Result<(), Error>;
 
     /// Renders a module (should not handle recursing into children).
     fn mod_item_in(&mut self, item: &clean::Item) -> Result<(), Error>;
@@ -67,14 +67,14 @@ pub(crate) trait FormatRenderer<'tcx>: Sized {
     }
 
     /// Post processing hook for cleanup and dumping output to files.
-    fn after_krate(&mut self) -> Result<(), Error>;
+    fn after_krate(self) -> Result<(), Error>;
 
     fn cache(&self) -> &Cache;
 }
 
 fn run_format_inner<'tcx, T: FormatRenderer<'tcx>>(
     cx: &mut T,
-    item: clean::Item,
+    item: &clean::Item,
     prof: &SelfProfilerRef,
 ) -> Result<(), Error> {
     if item.is_mod() && T::RUN_ON_MODULE {
@@ -84,12 +84,12 @@ fn run_format_inner<'tcx, T: FormatRenderer<'tcx>>(
             prof.generic_activity_with_arg("render_mod_item", item.name.unwrap().to_string());
 
         cx.mod_item_in(&item)?;
-        let (clean::StrippedItem(box clean::ModuleItem(module)) | clean::ModuleItem(module)) =
-            item.inner.kind
+        let (clean::StrippedItem(box clean::ModuleItem(ref module))
+        | clean::ModuleItem(ref module)) = item.inner.kind
         else {
             unreachable!()
         };
-        for it in module.items {
+        for it in module.items.iter() {
             let info = cx.save_module_data();
             run_format_inner(cx, it, prof)?;
             cx.restore_module_data(info);
@@ -101,7 +101,7 @@ fn run_format_inner<'tcx, T: FormatRenderer<'tcx>>(
     } else if let Some(item_name) = item.name
         && !item.is_extern_crate()
     {
-        prof.generic_activity_with_arg("render_item", item_name.as_str()).run(|| cx.item(item))?;
+        prof.generic_activity_with_arg("render_item", item_name.as_str()).run(|| cx.item(&item))?;
     }
     Ok(())
 }
@@ -125,7 +125,7 @@ pub(crate) fn run_format<'tcx, T: FormatRenderer<'tcx>>(
     }
 
     // Render the crate documentation
-    run_format_inner(&mut format_renderer, krate.module, prof)?;
+    run_format_inner(&mut format_renderer, &krate.module, prof)?;
 
     prof.verbose_generic_activity_with_arg("renderer_after_krate", T::descr())
         .run(|| format_renderer.after_krate())
diff --git a/src/librustdoc/html/markdown.rs b/src/librustdoc/html/markdown.rs
index d3701784f9d..f626e07b000 100644
--- a/src/librustdoc/html/markdown.rs
+++ b/src/librustdoc/html/markdown.rs
@@ -307,7 +307,8 @@ impl<'a, I: Iterator<Item = Event<'a>>> Iterator for CodeBlocks<'_, 'a, I> {
                 builder = builder.crate_name(krate);
             }
             let doctest = builder.build(None);
-            let (test, _) = doctest.generate_unique_doctest(&test, false, &opts, krate);
+            let (wrapped, _) = doctest.generate_unique_doctest(&test, false, &opts, krate);
+            let test = wrapped.to_string();
             let channel = if test.contains("#![feature(") { "&amp;version=nightly" } else { "" };
 
             let test_escaped = small_url_encode(test);
diff --git a/src/librustdoc/html/render/context.rs b/src/librustdoc/html/render/context.rs
index 5984dcd74ca..38214451657 100644
--- a/src/librustdoc/html/render/context.rs
+++ b/src/librustdoc/html/render/context.rs
@@ -609,7 +609,7 @@ impl<'tcx> FormatRenderer<'tcx> for Context<'tcx> {
         self.info = info;
     }
 
-    fn after_krate(&mut self) -> Result<(), Error> {
+    fn after_krate(mut self) -> Result<(), Error> {
         let crate_name = self.tcx().crate_name(LOCAL_CRATE);
         let final_file = self.dst.join(crate_name.as_str()).join("all.html");
         let settings_file = self.dst.join("settings.html");
@@ -830,7 +830,7 @@ impl<'tcx> FormatRenderer<'tcx> for Context<'tcx> {
         Ok(())
     }
 
-    fn item(&mut self, item: clean::Item) -> Result<(), Error> {
+    fn item(&mut self, item: &clean::Item) -> Result<(), Error> {
         // Stripped modules survive the rustdoc passes (i.e., `strip-private`)
         // if they contain impls for public types. These modules can also
         // contain items such as publicly re-exported structures.
diff --git a/src/librustdoc/html/render/write_shared.rs b/src/librustdoc/html/render/write_shared.rs
index 33738f7a242..fb2b45802a6 100644
--- a/src/librustdoc/html/render/write_shared.rs
+++ b/src/librustdoc/html/render/write_shared.rs
@@ -477,11 +477,7 @@ impl SourcesPart {
         // This needs to be `var`, not `const`.
         // This variable needs declared in the current global scope so that if
         // src-script.js loads first, it can pick it up.
-        SortedTemplate::from_before_after(
-            r"var srcIndex = new Map(JSON.parse('[",
-            r"]'));
-createSrcSidebar();",
-        )
+        SortedTemplate::from_before_after(r"createSrcSidebar('[", r"]');")
     }
 
     fn get(cx: &Context<'_>, crate_name: &OrderedJson) -> Result<PartsAndLocations<Self>, Error> {
diff --git a/src/librustdoc/html/render/write_shared/tests.rs b/src/librustdoc/html/render/write_shared/tests.rs
index a235f1d3724..6f185e85345 100644
--- a/src/librustdoc/html/render/write_shared/tests.rs
+++ b/src/librustdoc/html/render/write_shared/tests.rs
@@ -22,23 +22,11 @@ fn but_last_line(s: &str) -> &str {
 #[test]
 fn sources_template() {
     let mut template = SourcesPart::blank();
-    assert_eq!(
-        but_last_line(&template.to_string()),
-        r"var srcIndex = new Map(JSON.parse('[]'));
-createSrcSidebar();"
-    );
+    assert_eq!(but_last_line(&template.to_string()), r"createSrcSidebar('[]');");
     template.append(EscapedJson::from(OrderedJson::serialize("u").unwrap()).to_string());
-    assert_eq!(
-        but_last_line(&template.to_string()),
-        r#"var srcIndex = new Map(JSON.parse('["u"]'));
-createSrcSidebar();"#
-    );
+    assert_eq!(but_last_line(&template.to_string()), r#"createSrcSidebar('["u"]');"#);
     template.append(EscapedJson::from(OrderedJson::serialize("v").unwrap()).to_string());
-    assert_eq!(
-        but_last_line(&template.to_string()),
-        r#"var srcIndex = new Map(JSON.parse('["u","v"]'));
-createSrcSidebar();"#
-    );
+    assert_eq!(but_last_line(&template.to_string()), r#"createSrcSidebar('["u","v"]');"#);
 }
 
 #[test]
diff --git a/src/librustdoc/html/static/.eslintrc.js b/src/librustdoc/html/static/.eslintrc.js
index fbb096fe9c7..303c5667140 100644
--- a/src/librustdoc/html/static/.eslintrc.js
+++ b/src/librustdoc/html/static/.eslintrc.js
@@ -91,5 +91,6 @@ module.exports = {
         "no-script-url": "error",
         "no-sequences": "error",
         "no-div-regex": "error",
+        "no-console": "error",
     }
 };
diff --git a/src/librustdoc/html/static/js/rustdoc.d.ts b/src/librustdoc/html/static/js/rustdoc.d.ts
index 0d2e19e019f..6af16441de8 100644
--- a/src/librustdoc/html/static/js/rustdoc.d.ts
+++ b/src/librustdoc/html/static/js/rustdoc.d.ts
@@ -4,8 +4,6 @@
 
 /* eslint-disable */
 declare global {
-    /** Map from crate name to directory structure, for source view */
-    declare var srcIndex: Map<string, rustdoc.Dir>;
     /** Defined and documented in `storage.js` */
     declare function nonnull(x: T|null, msg: string|undefined);
     /** Defined and documented in `storage.js` */
@@ -64,7 +62,7 @@ declare global {
          * create's the sidebar in source code view.
          * called in generated `src-files.js`.
          */
-        createSrcSidebar?: function(),
+        createSrcSidebar?: function(string),
         /**
          * Set up event listeners for a scraped source example.
          */
@@ -129,7 +127,7 @@ declare namespace rustdoc {
 
     /**
      * A single parsed "atom" in a search query. For example,
-     * 
+     *
      *     std::fmt::Formatter, Write -> Result<()>
      *     ┏━━━━━━━━━━━━━━━━━━  ┌────    ┏━━━━━┅┅┅┅┄┄┄┄┄┄┄┄┄┄┄┄┄┄┐
      *     ┃                    │        ┗ QueryElement {        ┊
diff --git a/src/librustdoc/html/static/js/search.js b/src/librustdoc/html/static/js/search.js
index dce5fddb317..b611a3e501d 100644
--- a/src/librustdoc/html/static/js/search.js
+++ b/src/librustdoc/html/static/js/search.js
@@ -1133,6 +1133,7 @@ class RoaringBitmap {
         }
         for (let j = 0; j < size; ++j) {
             if (offsets && offsets[j] !== i) {
+                // eslint-disable-next-line no-console
                 console.log(this.containers);
                 throw new Error(`corrupt bitmap ${j}: ${i} / ${offsets[j]}`);
             }
diff --git a/src/librustdoc/html/static/js/src-script.js b/src/librustdoc/html/static/js/src-script.js
index b9ab6e85603..0c6afbeed22 100644
--- a/src/librustdoc/html/static/js/src-script.js
+++ b/src/librustdoc/html/static/js/src-script.js
@@ -1,6 +1,3 @@
-// From rust:
-/* global srcIndex */
-
 // Local js definitions:
 /* global addClass, onEachLazy, removeClass, browserSupportsHistoryApi */
 /* global updateLocalStorage, getVar, nonnull */
@@ -100,11 +97,15 @@ window.rustdocToggleSrcSidebar = () => {
 
 // This function is called from "src-files.js", generated in `html/render/write_shared.rs`.
 // eslint-disable-next-line no-unused-vars
-function createSrcSidebar() {
+/**
+ * @param {string} srcIndexStr - strinified json map from crate name to dir structure
+ */
+function createSrcSidebar(srcIndexStr) {
     const container = nonnull(document.querySelector("nav.sidebar"));
 
     const sidebar = document.createElement("div");
     sidebar.id = "src-sidebar";
+    const srcIndex = new Map(JSON.parse(srcIndexStr));
 
     let hasFoundFile = false;
 
diff --git a/src/librustdoc/json/conversions.rs b/src/librustdoc/json/conversions.rs
index 3ade40940bc..6bdf3b5fe38 100644
--- a/src/librustdoc/json/conversions.rs
+++ b/src/librustdoc/json/conversions.rs
@@ -13,6 +13,7 @@ use rustc_metadata::rendered_const;
 use rustc_middle::{bug, ty};
 use rustc_span::{Pos, Symbol, kw};
 use rustdoc_json_types::*;
+use thin_vec::ThinVec;
 
 use crate::clean::{self, ItemId};
 use crate::formats::FormatRenderer;
@@ -21,7 +22,7 @@ use crate::json::JsonRenderer;
 use crate::passes::collect_intra_doc_links::UrlFragment;
 
 impl JsonRenderer<'_> {
-    pub(super) fn convert_item(&self, item: clean::Item) -> Option<Item> {
+    pub(super) fn convert_item(&self, item: &clean::Item) -> Option<Item> {
         let deprecation = item.deprecation(self.tcx);
         let links = self
             .cache
@@ -107,49 +108,54 @@ impl JsonRenderer<'_> {
         }
     }
 
-    fn ids(&self, items: impl IntoIterator<Item = clean::Item>) -> Vec<Id> {
+    fn ids(&self, items: &[clean::Item]) -> Vec<Id> {
         items
-            .into_iter()
-            .filter(|x| !x.is_stripped() && !x.is_keyword())
+            .iter()
+            .filter(|i| !i.is_stripped() && !i.is_keyword())
             .map(|i| self.id_from_item(&i))
             .collect()
     }
 
-    fn ids_keeping_stripped(
-        &self,
-        items: impl IntoIterator<Item = clean::Item>,
-    ) -> Vec<Option<Id>> {
+    fn ids_keeping_stripped(&self, items: &[clean::Item]) -> Vec<Option<Id>> {
         items
-            .into_iter()
+            .iter()
             .map(|i| (!i.is_stripped() && !i.is_keyword()).then(|| self.id_from_item(&i)))
             .collect()
     }
 }
 
 pub(crate) trait FromClean<T> {
-    fn from_clean(f: T, renderer: &JsonRenderer<'_>) -> Self;
+    fn from_clean(f: &T, renderer: &JsonRenderer<'_>) -> Self;
 }
 
 pub(crate) trait IntoJson<T> {
-    fn into_json(self, renderer: &JsonRenderer<'_>) -> T;
+    fn into_json(&self, renderer: &JsonRenderer<'_>) -> T;
 }
 
 impl<T, U> IntoJson<U> for T
 where
     U: FromClean<T>,
 {
-    fn into_json(self, renderer: &JsonRenderer<'_>) -> U {
+    fn into_json(&self, renderer: &JsonRenderer<'_>) -> U {
         U::from_clean(self, renderer)
     }
 }
 
-impl<I, T, U> FromClean<I> for Vec<U>
+impl<T, U> FromClean<Vec<T>> for Vec<U>
 where
-    I: IntoIterator<Item = T>,
     U: FromClean<T>,
 {
-    fn from_clean(f: I, renderer: &JsonRenderer<'_>) -> Vec<U> {
-        f.into_iter().map(|x| x.into_json(renderer)).collect()
+    fn from_clean(items: &Vec<T>, renderer: &JsonRenderer<'_>) -> Vec<U> {
+        items.iter().map(|i| i.into_json(renderer)).collect()
+    }
+}
+
+impl<T, U> FromClean<ThinVec<T>> for Vec<U>
+where
+    U: FromClean<T>,
+{
+    fn from_clean(items: &ThinVec<T>, renderer: &JsonRenderer<'_>) -> Vec<U> {
+        items.iter().map(|i| i.into_json(renderer)).collect()
     }
 }
 
@@ -165,7 +171,7 @@ pub(crate) fn from_deprecation(deprecation: attrs::Deprecation) -> Deprecation {
 }
 
 impl FromClean<clean::GenericArgs> for GenericArgs {
-    fn from_clean(args: clean::GenericArgs, renderer: &JsonRenderer<'_>) -> Self {
+    fn from_clean(args: &clean::GenericArgs, renderer: &JsonRenderer<'_>) -> Self {
         use clean::GenericArgs::*;
         match args {
             AngleBracketed { args, constraints } => GenericArgs::AngleBracketed {
@@ -174,7 +180,7 @@ impl FromClean<clean::GenericArgs> for GenericArgs {
             },
             Parenthesized { inputs, output } => GenericArgs::Parenthesized {
                 inputs: inputs.into_json(renderer),
-                output: output.map(|a| (*a).into_json(renderer)),
+                output: output.as_ref().map(|a| a.as_ref().into_json(renderer)),
             },
             ReturnTypeNotation => GenericArgs::ReturnTypeNotation,
         }
@@ -182,7 +188,7 @@ impl FromClean<clean::GenericArgs> for GenericArgs {
 }
 
 impl FromClean<clean::GenericArg> for GenericArg {
-    fn from_clean(arg: clean::GenericArg, renderer: &JsonRenderer<'_>) -> Self {
+    fn from_clean(arg: &clean::GenericArg, renderer: &JsonRenderer<'_>) -> Self {
         use clean::GenericArg::*;
         match arg {
             Lifetime(l) => GenericArg::Lifetime(convert_lifetime(l)),
@@ -195,7 +201,7 @@ impl FromClean<clean::GenericArg> for GenericArg {
 
 impl FromClean<clean::Constant> for Constant {
     // FIXME(generic_const_items): Add support for generic const items.
-    fn from_clean(constant: clean::Constant, renderer: &JsonRenderer<'_>) -> Self {
+    fn from_clean(constant: &clean::Constant, renderer: &JsonRenderer<'_>) -> Self {
         let tcx = renderer.tcx;
         let expr = constant.expr(tcx);
         let value = constant.value(tcx);
@@ -206,7 +212,7 @@ impl FromClean<clean::Constant> for Constant {
 
 impl FromClean<clean::ConstantKind> for Constant {
     // FIXME(generic_const_items): Add support for generic const items.
-    fn from_clean(constant: clean::ConstantKind, renderer: &JsonRenderer<'_>) -> Self {
+    fn from_clean(constant: &clean::ConstantKind, renderer: &JsonRenderer<'_>) -> Self {
         let tcx = renderer.tcx;
         let expr = constant.expr(tcx);
         let value = constant.value(tcx);
@@ -216,7 +222,7 @@ impl FromClean<clean::ConstantKind> for Constant {
 }
 
 impl FromClean<clean::AssocItemConstraint> for AssocItemConstraint {
-    fn from_clean(constraint: clean::AssocItemConstraint, renderer: &JsonRenderer<'_>) -> Self {
+    fn from_clean(constraint: &clean::AssocItemConstraint, renderer: &JsonRenderer<'_>) -> Self {
         AssocItemConstraint {
             name: constraint.assoc.name.to_string(),
             args: constraint.assoc.args.into_json(renderer),
@@ -226,7 +232,7 @@ impl FromClean<clean::AssocItemConstraint> for AssocItemConstraint {
 }
 
 impl FromClean<clean::AssocItemConstraintKind> for AssocItemConstraintKind {
-    fn from_clean(kind: clean::AssocItemConstraintKind, renderer: &JsonRenderer<'_>) -> Self {
+    fn from_clean(kind: &clean::AssocItemConstraintKind, renderer: &JsonRenderer<'_>) -> Self {
         use clean::AssocItemConstraintKind::*;
         match kind {
             Equality { term } => AssocItemConstraintKind::Equality(term.into_json(renderer)),
@@ -235,15 +241,15 @@ impl FromClean<clean::AssocItemConstraintKind> for AssocItemConstraintKind {
     }
 }
 
-fn from_clean_item(item: clean::Item, renderer: &JsonRenderer<'_>) -> ItemEnum {
+fn from_clean_item(item: &clean::Item, renderer: &JsonRenderer<'_>) -> ItemEnum {
     use clean::ItemKind::*;
     let name = item.name;
     let is_crate = item.is_crate();
     let header = item.fn_header(renderer.tcx);
 
-    match item.inner.kind {
+    match &item.inner.kind {
         ModuleItem(m) => {
-            ItemEnum::Module(Module { is_crate, items: renderer.ids(m.items), is_stripped: false })
+            ItemEnum::Module(Module { is_crate, items: renderer.ids(&m.items), is_stripped: false })
         }
         ImportItem(i) => ItemEnum::Use(i.into_json(renderer)),
         StructItem(s) => ItemEnum::Struct(s.into_json(renderer)),
@@ -251,27 +257,27 @@ fn from_clean_item(item: clean::Item, renderer: &JsonRenderer<'_>) -> ItemEnum {
         StructFieldItem(f) => ItemEnum::StructField(f.into_json(renderer)),
         EnumItem(e) => ItemEnum::Enum(e.into_json(renderer)),
         VariantItem(v) => ItemEnum::Variant(v.into_json(renderer)),
-        FunctionItem(f) => ItemEnum::Function(from_function(*f, true, header.unwrap(), renderer)),
+        FunctionItem(f) => ItemEnum::Function(from_function(f, true, header.unwrap(), renderer)),
         ForeignFunctionItem(f, _) => {
-            ItemEnum::Function(from_function(*f, false, header.unwrap(), renderer))
+            ItemEnum::Function(from_function(f, false, header.unwrap(), renderer))
         }
-        TraitItem(t) => ItemEnum::Trait((*t).into_json(renderer)),
+        TraitItem(t) => ItemEnum::Trait(t.as_ref().into_json(renderer)),
         TraitAliasItem(t) => ItemEnum::TraitAlias(t.into_json(renderer)),
-        MethodItem(m, _) => ItemEnum::Function(from_function(*m, true, header.unwrap(), renderer)),
+        MethodItem(m, _) => ItemEnum::Function(from_function(m, true, header.unwrap(), renderer)),
         RequiredMethodItem(m) => {
-            ItemEnum::Function(from_function(*m, false, header.unwrap(), renderer))
+            ItemEnum::Function(from_function(m, false, header.unwrap(), renderer))
         }
-        ImplItem(i) => ItemEnum::Impl((*i).into_json(renderer)),
-        StaticItem(s) => ItemEnum::Static(convert_static(s, rustc_hir::Safety::Safe, renderer)),
+        ImplItem(i) => ItemEnum::Impl(i.as_ref().into_json(renderer)),
+        StaticItem(s) => ItemEnum::Static(convert_static(s, &rustc_hir::Safety::Safe, renderer)),
         ForeignStaticItem(s, safety) => ItemEnum::Static(convert_static(s, safety, renderer)),
         ForeignTypeItem => ItemEnum::ExternType,
-        TypeAliasItem(t) => ItemEnum::TypeAlias(t.into_json(renderer)),
+        TypeAliasItem(t) => ItemEnum::TypeAlias(t.as_ref().into_json(renderer)),
         // FIXME(generic_const_items): Add support for generic free consts
         ConstantItem(ci) => ItemEnum::Constant {
             type_: ci.type_.into_json(renderer),
             const_: ci.kind.into_json(renderer),
         },
-        MacroItem(m) => ItemEnum::Macro(m.source),
+        MacroItem(m) => ItemEnum::Macro(m.source.clone()),
         ProcMacroItem(m) => ItemEnum::ProcMacro(m.into_json(renderer)),
         PrimitiveItem(p) => {
             ItemEnum::Primitive(Primitive {
@@ -281,7 +287,7 @@ fn from_clean_item(item: clean::Item, renderer: &JsonRenderer<'_>) -> ItemEnum {
         }
         // FIXME(generic_const_items): Add support for generic associated consts.
         RequiredAssocConstItem(_generics, ty) => {
-            ItemEnum::AssocConst { type_: (*ty).into_json(renderer), value: None }
+            ItemEnum::AssocConst { type_: ty.as_ref().into_json(renderer), value: None }
         }
         // FIXME(generic_const_items): Add support for generic associated consts.
         ProvidedAssocConstItem(ci) | ImplAssocConstItem(ci) => ItemEnum::AssocConst {
@@ -296,22 +302,22 @@ fn from_clean_item(item: clean::Item, renderer: &JsonRenderer<'_>) -> ItemEnum {
         AssocTypeItem(t, b) => ItemEnum::AssocType {
             generics: t.generics.into_json(renderer),
             bounds: b.into_json(renderer),
-            type_: Some(t.item_type.unwrap_or(t.type_).into_json(renderer)),
+            type_: Some(t.item_type.as_ref().unwrap_or(&t.type_).into_json(renderer)),
         },
         // `convert_item` early returns `None` for stripped items and keywords.
         KeywordItem => unreachable!(),
         StrippedItem(inner) => {
-            match *inner {
+            match inner.as_ref() {
                 ModuleItem(m) => ItemEnum::Module(Module {
                     is_crate,
-                    items: renderer.ids(m.items),
+                    items: renderer.ids(&m.items),
                     is_stripped: true,
                 }),
                 // `convert_item` early returns `None` for stripped items we're not including
                 _ => unreachable!(),
             }
         }
-        ExternCrateItem { ref src } => ItemEnum::ExternCrate {
+        ExternCrateItem { src } => ItemEnum::ExternCrate {
             name: name.as_ref().unwrap().to_string(),
             rename: src.map(|x| x.to_string()),
         },
@@ -319,17 +325,17 @@ fn from_clean_item(item: clean::Item, renderer: &JsonRenderer<'_>) -> ItemEnum {
 }
 
 impl FromClean<clean::Struct> for Struct {
-    fn from_clean(struct_: clean::Struct, renderer: &JsonRenderer<'_>) -> Self {
+    fn from_clean(struct_: &clean::Struct, renderer: &JsonRenderer<'_>) -> Self {
         let has_stripped_fields = struct_.has_stripped_entries();
         let clean::Struct { ctor_kind, generics, fields } = struct_;
 
         let kind = match ctor_kind {
-            Some(CtorKind::Fn) => StructKind::Tuple(renderer.ids_keeping_stripped(fields)),
+            Some(CtorKind::Fn) => StructKind::Tuple(renderer.ids_keeping_stripped(&fields)),
             Some(CtorKind::Const) => {
                 assert!(fields.is_empty());
                 StructKind::Unit
             }
-            None => StructKind::Plain { fields: renderer.ids(fields), has_stripped_fields },
+            None => StructKind::Plain { fields: renderer.ids(&fields), has_stripped_fields },
         };
 
         Struct {
@@ -341,13 +347,13 @@ impl FromClean<clean::Struct> for Struct {
 }
 
 impl FromClean<clean::Union> for Union {
-    fn from_clean(union_: clean::Union, renderer: &JsonRenderer<'_>) -> Self {
+    fn from_clean(union_: &clean::Union, renderer: &JsonRenderer<'_>) -> Self {
         let has_stripped_fields = union_.has_stripped_entries();
         let clean::Union { generics, fields } = union_;
         Union {
             generics: generics.into_json(renderer),
             has_stripped_fields,
-            fields: renderer.ids(fields),
+            fields: renderer.ids(&fields),
             impls: Vec::new(), // Added in JsonRenderer::item
         }
     }
@@ -377,12 +383,12 @@ fn convert_abi(a: ExternAbi) -> Abi {
     }
 }
 
-fn convert_lifetime(l: clean::Lifetime) -> String {
+fn convert_lifetime(l: &clean::Lifetime) -> String {
     l.0.to_string()
 }
 
 impl FromClean<clean::Generics> for Generics {
-    fn from_clean(generics: clean::Generics, renderer: &JsonRenderer<'_>) -> Self {
+    fn from_clean(generics: &clean::Generics, renderer: &JsonRenderer<'_>) -> Self {
         Generics {
             params: generics.params.into_json(renderer),
             where_predicates: generics.where_predicates.into_json(renderer),
@@ -391,7 +397,7 @@ impl FromClean<clean::Generics> for Generics {
 }
 
 impl FromClean<clean::GenericParamDef> for GenericParamDef {
-    fn from_clean(generic_param: clean::GenericParamDef, renderer: &JsonRenderer<'_>) -> Self {
+    fn from_clean(generic_param: &clean::GenericParamDef, renderer: &JsonRenderer<'_>) -> Self {
         GenericParamDef {
             name: generic_param.name.to_string(),
             kind: generic_param.kind.into_json(renderer),
@@ -400,7 +406,7 @@ impl FromClean<clean::GenericParamDef> for GenericParamDef {
 }
 
 impl FromClean<clean::GenericParamDefKind> for GenericParamDefKind {
-    fn from_clean(kind: clean::GenericParamDefKind, renderer: &JsonRenderer<'_>) -> Self {
+    fn from_clean(kind: &clean::GenericParamDefKind, renderer: &JsonRenderer<'_>) -> Self {
         use clean::GenericParamDefKind::*;
         match kind {
             Lifetime { outlives } => GenericParamDefKind::Lifetime {
@@ -408,29 +414,29 @@ impl FromClean<clean::GenericParamDefKind> for GenericParamDefKind {
             },
             Type { bounds, default, synthetic } => GenericParamDefKind::Type {
                 bounds: bounds.into_json(renderer),
-                default: default.map(|x| (*x).into_json(renderer)),
-                is_synthetic: synthetic,
+                default: default.as_ref().map(|x| x.as_ref().into_json(renderer)),
+                is_synthetic: *synthetic,
             },
             Const { ty, default, synthetic: _ } => GenericParamDefKind::Const {
-                type_: (*ty).into_json(renderer),
-                default: default.map(|x| *x),
+                type_: ty.as_ref().into_json(renderer),
+                default: default.as_ref().map(|x| x.as_ref().clone()),
             },
         }
     }
 }
 
 impl FromClean<clean::WherePredicate> for WherePredicate {
-    fn from_clean(predicate: clean::WherePredicate, renderer: &JsonRenderer<'_>) -> Self {
+    fn from_clean(predicate: &clean::WherePredicate, renderer: &JsonRenderer<'_>) -> Self {
         use clean::WherePredicate::*;
         match predicate {
             BoundPredicate { ty, bounds, bound_params } => WherePredicate::BoundPredicate {
                 type_: ty.into_json(renderer),
                 bounds: bounds.into_json(renderer),
                 generic_params: bound_params
-                    .into_iter()
+                    .iter()
                     .map(|x| {
                         let name = x.name.to_string();
-                        let kind = match x.kind {
+                        let kind = match &x.kind {
                             clean::GenericParamDefKind::Lifetime { outlives } => {
                                 GenericParamDefKind::Lifetime {
                                     outlives: outlives.iter().map(|lt| lt.0.to_string()).collect(),
@@ -442,14 +448,16 @@ impl FromClean<clean::WherePredicate> for WherePredicate {
                                         .into_iter()
                                         .map(|bound| bound.into_json(renderer))
                                         .collect(),
-                                    default: default.map(|ty| (*ty).into_json(renderer)),
-                                    is_synthetic: synthetic,
+                                    default: default
+                                        .as_ref()
+                                        .map(|ty| ty.as_ref().into_json(renderer)),
+                                    is_synthetic: *synthetic,
                                 }
                             }
                             clean::GenericParamDefKind::Const { ty, default, synthetic: _ } => {
                                 GenericParamDefKind::Const {
-                                    type_: (*ty).into_json(renderer),
-                                    default: default.map(|d| *d),
+                                    type_: ty.as_ref().into_json(renderer),
+                                    default: default.as_ref().map(|d| d.as_ref().clone()),
                                 }
                             }
                         };
@@ -462,7 +470,7 @@ impl FromClean<clean::WherePredicate> for WherePredicate {
                 outlives: bounds
                     .iter()
                     .map(|bound| match bound {
-                        clean::GenericBound::Outlives(lt) => convert_lifetime(*lt),
+                        clean::GenericBound::Outlives(lt) => convert_lifetime(lt),
                         _ => bug!("found non-outlives-bound on lifetime predicate"),
                     })
                     .collect(),
@@ -479,7 +487,7 @@ impl FromClean<clean::WherePredicate> for WherePredicate {
 }
 
 impl FromClean<clean::GenericBound> for GenericBound {
-    fn from_clean(bound: clean::GenericBound, renderer: &JsonRenderer<'_>) -> Self {
+    fn from_clean(bound: &clean::GenericBound, renderer: &JsonRenderer<'_>) -> Self {
         use clean::GenericBound::*;
         match bound {
             TraitBound(clean::PolyTrait { trait_, generic_params }, modifier) => {
@@ -494,7 +502,7 @@ impl FromClean<clean::GenericBound> for GenericBound {
                 args.iter()
                     .map(|arg| match arg {
                         clean::PreciseCapturingArg::Lifetime(lt) => {
-                            PreciseCapturingArg::Lifetime(convert_lifetime(*lt))
+                            PreciseCapturingArg::Lifetime(convert_lifetime(lt))
                         }
                         clean::PreciseCapturingArg::Param(param) => {
                             PreciseCapturingArg::Param(param.to_string())
@@ -507,7 +515,7 @@ impl FromClean<clean::GenericBound> for GenericBound {
 }
 
 pub(crate) fn from_trait_bound_modifier(
-    modifiers: rustc_hir::TraitBoundModifiers,
+    modifiers: &rustc_hir::TraitBoundModifiers,
 ) -> TraitBoundModifier {
     use rustc_hir as hir;
     let hir::TraitBoundModifiers { constness, polarity } = modifiers;
@@ -523,7 +531,7 @@ pub(crate) fn from_trait_bound_modifier(
 }
 
 impl FromClean<clean::Type> for Type {
-    fn from_clean(ty: clean::Type, renderer: &JsonRenderer<'_>) -> Self {
+    fn from_clean(ty: &clean::Type, renderer: &JsonRenderer<'_>) -> Self {
         use clean::Type::{
             Array, BareFunction, BorrowedRef, Generic, ImplTrait, Infer, Primitive, QPath,
             RawPointer, SelfTy, Slice, Tuple, UnsafeBinder,
@@ -532,35 +540,35 @@ impl FromClean<clean::Type> for Type {
         match ty {
             clean::Type::Path { path } => Type::ResolvedPath(path.into_json(renderer)),
             clean::Type::DynTrait(bounds, lt) => Type::DynTrait(DynTrait {
-                lifetime: lt.map(convert_lifetime),
+                lifetime: lt.as_ref().map(convert_lifetime),
                 traits: bounds.into_json(renderer),
             }),
             Generic(s) => Type::Generic(s.to_string()),
             // FIXME: add dedicated variant to json Type?
             SelfTy => Type::Generic("Self".to_owned()),
             Primitive(p) => Type::Primitive(p.as_sym().to_string()),
-            BareFunction(f) => Type::FunctionPointer(Box::new((*f).into_json(renderer))),
+            BareFunction(f) => Type::FunctionPointer(Box::new(f.as_ref().into_json(renderer))),
             Tuple(t) => Type::Tuple(t.into_json(renderer)),
-            Slice(t) => Type::Slice(Box::new((*t).into_json(renderer))),
+            Slice(t) => Type::Slice(Box::new(t.as_ref().into_json(renderer))),
             Array(t, s) => {
-                Type::Array { type_: Box::new((*t).into_json(renderer)), len: s.to_string() }
+                Type::Array { type_: Box::new(t.as_ref().into_json(renderer)), len: s.to_string() }
             }
             clean::Type::Pat(t, p) => Type::Pat {
-                type_: Box::new((*t).into_json(renderer)),
+                type_: Box::new(t.as_ref().into_json(renderer)),
                 __pat_unstable_do_not_use: p.to_string(),
             },
             ImplTrait(g) => Type::ImplTrait(g.into_json(renderer)),
             Infer => Type::Infer,
             RawPointer(mutability, type_) => Type::RawPointer {
-                is_mutable: mutability == ast::Mutability::Mut,
-                type_: Box::new((*type_).into_json(renderer)),
+                is_mutable: *mutability == ast::Mutability::Mut,
+                type_: Box::new(type_.as_ref().into_json(renderer)),
             },
             BorrowedRef { lifetime, mutability, type_ } => Type::BorrowedRef {
-                lifetime: lifetime.map(convert_lifetime),
-                is_mutable: mutability == ast::Mutability::Mut,
-                type_: Box::new((*type_).into_json(renderer)),
+                lifetime: lifetime.as_ref().map(convert_lifetime),
+                is_mutable: *mutability == ast::Mutability::Mut,
+                type_: Box::new(type_.as_ref().into_json(renderer)),
             },
-            QPath(qpath) => (*qpath).into_json(renderer),
+            QPath(qpath) => qpath.as_ref().into_json(renderer),
             // FIXME(unsafe_binder): Implement rustdoc-json.
             UnsafeBinder(_) => todo!(),
         }
@@ -568,30 +576,30 @@ impl FromClean<clean::Type> for Type {
 }
 
 impl FromClean<clean::Path> for Path {
-    fn from_clean(path: clean::Path, renderer: &JsonRenderer<'_>) -> Path {
+    fn from_clean(path: &clean::Path, renderer: &JsonRenderer<'_>) -> Path {
         Path {
             path: path.whole_name(),
             id: renderer.id_from_item_default(path.def_id().into()),
-            args: path.segments.last().map(|args| Box::new(args.clone().args.into_json(renderer))),
+            args: path.segments.last().map(|args| Box::new(args.args.into_json(renderer))),
         }
     }
 }
 
 impl FromClean<clean::QPathData> for Type {
-    fn from_clean(qpath: clean::QPathData, renderer: &JsonRenderer<'_>) -> Self {
+    fn from_clean(qpath: &clean::QPathData, renderer: &JsonRenderer<'_>) -> Self {
         let clean::QPathData { assoc, self_type, should_fully_qualify: _, trait_ } = qpath;
 
         Self::QualifiedPath {
             name: assoc.name.to_string(),
             args: Box::new(assoc.args.into_json(renderer)),
             self_type: Box::new(self_type.into_json(renderer)),
-            trait_: trait_.map(|trait_| trait_.into_json(renderer)),
+            trait_: trait_.as_ref().map(|trait_| trait_.into_json(renderer)),
         }
     }
 }
 
 impl FromClean<clean::Term> for Term {
-    fn from_clean(term: clean::Term, renderer: &JsonRenderer<'_>) -> Term {
+    fn from_clean(term: &clean::Term, renderer: &JsonRenderer<'_>) -> Term {
         match term {
             clean::Term::Type(ty) => Term::Type(ty.into_json(renderer)),
             clean::Term::Constant(c) => Term::Constant(c.into_json(renderer)),
@@ -600,14 +608,14 @@ impl FromClean<clean::Term> for Term {
 }
 
 impl FromClean<clean::BareFunctionDecl> for FunctionPointer {
-    fn from_clean(bare_decl: clean::BareFunctionDecl, renderer: &JsonRenderer<'_>) -> Self {
+    fn from_clean(bare_decl: &clean::BareFunctionDecl, renderer: &JsonRenderer<'_>) -> Self {
         let clean::BareFunctionDecl { safety, generic_params, decl, abi } = bare_decl;
         FunctionPointer {
             header: FunctionHeader {
                 is_unsafe: safety.is_unsafe(),
                 is_const: false,
                 is_async: false,
-                abi: convert_abi(abi),
+                abi: convert_abi(*abi),
             },
             generic_params: generic_params.into_json(renderer),
             sig: decl.into_json(renderer),
@@ -616,7 +624,7 @@ impl FromClean<clean::BareFunctionDecl> for FunctionPointer {
 }
 
 impl FromClean<clean::FnDecl> for FunctionSignature {
-    fn from_clean(decl: clean::FnDecl, renderer: &JsonRenderer<'_>) -> Self {
+    fn from_clean(decl: &clean::FnDecl, renderer: &JsonRenderer<'_>) -> Self {
         let clean::FnDecl { inputs, output, c_variadic } = decl;
         FunctionSignature {
             inputs: inputs
@@ -629,13 +637,13 @@ impl FromClean<clean::FnDecl> for FunctionSignature {
                 })
                 .collect(),
             output: if output.is_unit() { None } else { Some(output.into_json(renderer)) },
-            is_c_variadic: c_variadic,
+            is_c_variadic: *c_variadic,
         }
     }
 }
 
 impl FromClean<clean::Trait> for Trait {
-    fn from_clean(trait_: clean::Trait, renderer: &JsonRenderer<'_>) -> Self {
+    fn from_clean(trait_: &clean::Trait, renderer: &JsonRenderer<'_>) -> Self {
         let tcx = renderer.tcx;
         let is_auto = trait_.is_auto(tcx);
         let is_unsafe = trait_.safety(tcx).is_unsafe();
@@ -645,7 +653,7 @@ impl FromClean<clean::Trait> for Trait {
             is_auto,
             is_unsafe,
             is_dyn_compatible,
-            items: renderer.ids(items),
+            items: renderer.ids(&items),
             generics: generics.into_json(renderer),
             bounds: bounds.into_json(renderer),
             implementations: Vec::new(), // Added in JsonRenderer::item
@@ -655,7 +663,7 @@ impl FromClean<clean::Trait> for Trait {
 
 impl FromClean<clean::PolyTrait> for PolyTrait {
     fn from_clean(
-        clean::PolyTrait { trait_, generic_params }: clean::PolyTrait,
+        clean::PolyTrait { trait_, generic_params }: &clean::PolyTrait,
         renderer: &JsonRenderer<'_>,
     ) -> Self {
         PolyTrait {
@@ -666,14 +674,14 @@ impl FromClean<clean::PolyTrait> for PolyTrait {
 }
 
 impl FromClean<clean::Impl> for Impl {
-    fn from_clean(impl_: clean::Impl, renderer: &JsonRenderer<'_>) -> Self {
+    fn from_clean(impl_: &clean::Impl, renderer: &JsonRenderer<'_>) -> Self {
         let provided_trait_methods = impl_.provided_trait_methods(renderer.tcx);
         let clean::Impl { safety, generics, trait_, for_, items, polarity, kind } = impl_;
         // FIXME: use something like ImplKind in JSON?
         let (is_synthetic, blanket_impl) = match kind {
             clean::ImplKind::Normal | clean::ImplKind::FakeVariadic => (false, None),
             clean::ImplKind::Auto => (true, None),
-            clean::ImplKind::Blanket(ty) => (false, Some(*ty)),
+            clean::ImplKind::Blanket(ty) => (false, Some(ty)),
         };
         let is_negative = match polarity {
             ty::ImplPolarity::Positive | ty::ImplPolarity::Reservation => false,
@@ -686,18 +694,18 @@ impl FromClean<clean::Impl> for Impl {
                 .into_iter()
                 .map(|x| x.to_string())
                 .collect(),
-            trait_: trait_.map(|path| path.into_json(renderer)),
+            trait_: trait_.as_ref().map(|path| path.into_json(renderer)),
             for_: for_.into_json(renderer),
-            items: renderer.ids(items),
+            items: renderer.ids(&items),
             is_negative,
             is_synthetic,
-            blanket_impl: blanket_impl.map(|x| x.into_json(renderer)),
+            blanket_impl: blanket_impl.map(|x| x.as_ref().into_json(renderer)),
         }
     }
 }
 
 pub(crate) fn from_function(
-    clean::Function { decl, generics }: clean::Function,
+    clean::Function { decl, generics }: &clean::Function,
     has_body: bool,
     header: rustc_hir::FnHeader,
     renderer: &JsonRenderer<'_>,
@@ -711,30 +719,30 @@ pub(crate) fn from_function(
 }
 
 impl FromClean<clean::Enum> for Enum {
-    fn from_clean(enum_: clean::Enum, renderer: &JsonRenderer<'_>) -> Self {
+    fn from_clean(enum_: &clean::Enum, renderer: &JsonRenderer<'_>) -> Self {
         let has_stripped_variants = enum_.has_stripped_entries();
         let clean::Enum { variants, generics } = enum_;
         Enum {
             generics: generics.into_json(renderer),
             has_stripped_variants,
-            variants: renderer.ids(variants),
+            variants: renderer.ids(&variants.as_slice().raw),
             impls: Vec::new(), // Added in JsonRenderer::item
         }
     }
 }
 
 impl FromClean<clean::Variant> for Variant {
-    fn from_clean(variant: clean::Variant, renderer: &JsonRenderer<'_>) -> Self {
+    fn from_clean(variant: &clean::Variant, renderer: &JsonRenderer<'_>) -> Self {
         use clean::VariantKind::*;
 
-        let discriminant = variant.discriminant.map(|d| d.into_json(renderer));
+        let discriminant = variant.discriminant.as_ref().map(|d| d.into_json(renderer));
 
-        let kind = match variant.kind {
+        let kind = match &variant.kind {
             CLike => VariantKind::Plain,
-            Tuple(fields) => VariantKind::Tuple(renderer.ids_keeping_stripped(fields)),
+            Tuple(fields) => VariantKind::Tuple(renderer.ids_keeping_stripped(&fields)),
             Struct(s) => VariantKind::Struct {
                 has_stripped_fields: s.has_stripped_entries(),
-                fields: renderer.ids(s.fields),
+                fields: renderer.ids(&s.fields),
             },
         };
 
@@ -743,7 +751,7 @@ impl FromClean<clean::Variant> for Variant {
 }
 
 impl FromClean<clean::Discriminant> for Discriminant {
-    fn from_clean(disr: clean::Discriminant, renderer: &JsonRenderer<'_>) -> Self {
+    fn from_clean(disr: &clean::Discriminant, renderer: &JsonRenderer<'_>) -> Self {
         let tcx = renderer.tcx;
         Discriminant {
             // expr is only none if going through the inlining path, which gets
@@ -756,7 +764,7 @@ impl FromClean<clean::Discriminant> for Discriminant {
 }
 
 impl FromClean<clean::Import> for Use {
-    fn from_clean(import: clean::Import, renderer: &JsonRenderer<'_>) -> Self {
+    fn from_clean(import: &clean::Import, renderer: &JsonRenderer<'_>) -> Self {
         use clean::ImportKind::*;
         let (name, is_glob) = match import.kind {
             Simple(s) => (s.to_string(), false),
@@ -775,7 +783,7 @@ impl FromClean<clean::Import> for Use {
 }
 
 impl FromClean<clean::ProcMacro> for ProcMacro {
-    fn from_clean(mac: clean::ProcMacro, _renderer: &JsonRenderer<'_>) -> Self {
+    fn from_clean(mac: &clean::ProcMacro, _renderer: &JsonRenderer<'_>) -> Self {
         ProcMacro {
             kind: from_macro_kind(mac.kind),
             helpers: mac.helpers.iter().map(|x| x.to_string()).collect(),
@@ -792,21 +800,21 @@ pub(crate) fn from_macro_kind(kind: rustc_span::hygiene::MacroKind) -> MacroKind
     }
 }
 
-impl FromClean<Box<clean::TypeAlias>> for TypeAlias {
-    fn from_clean(type_alias: Box<clean::TypeAlias>, renderer: &JsonRenderer<'_>) -> Self {
-        let clean::TypeAlias { type_, generics, item_type: _, inner_type: _ } = *type_alias;
+impl FromClean<clean::TypeAlias> for TypeAlias {
+    fn from_clean(type_alias: &clean::TypeAlias, renderer: &JsonRenderer<'_>) -> Self {
+        let clean::TypeAlias { type_, generics, item_type: _, inner_type: _ } = type_alias;
         TypeAlias { type_: type_.into_json(renderer), generics: generics.into_json(renderer) }
     }
 }
 
 fn convert_static(
-    stat: clean::Static,
-    safety: rustc_hir::Safety,
+    stat: &clean::Static,
+    safety: &rustc_hir::Safety,
     renderer: &JsonRenderer<'_>,
 ) -> Static {
     let tcx = renderer.tcx;
     Static {
-        type_: (*stat.type_).into_json(renderer),
+        type_: stat.type_.as_ref().into_json(renderer),
         is_mutable: stat.mutability == ast::Mutability::Mut,
         is_unsafe: safety.is_unsafe(),
         expr: stat
@@ -817,7 +825,7 @@ fn convert_static(
 }
 
 impl FromClean<clean::TraitAlias> for TraitAlias {
-    fn from_clean(alias: clean::TraitAlias, renderer: &JsonRenderer<'_>) -> Self {
+    fn from_clean(alias: &clean::TraitAlias, renderer: &JsonRenderer<'_>) -> Self {
         TraitAlias {
             generics: alias.generics.into_json(renderer),
             params: alias.bounds.into_json(renderer),
@@ -826,7 +834,7 @@ impl FromClean<clean::TraitAlias> for TraitAlias {
 }
 
 impl FromClean<ItemType> for ItemKind {
-    fn from_clean(kind: ItemType, _renderer: &JsonRenderer<'_>) -> Self {
+    fn from_clean(kind: &ItemType, _renderer: &JsonRenderer<'_>) -> Self {
         use ItemType::*;
         match kind {
             Module => ItemKind::Module,
diff --git a/src/librustdoc/json/mod.rs b/src/librustdoc/json/mod.rs
index 131a12ce228..2feadce26d0 100644
--- a/src/librustdoc/json/mod.rs
+++ b/src/librustdoc/json/mod.rs
@@ -18,6 +18,7 @@ use rustc_data_structures::fx::FxHashSet;
 use rustc_hir::def_id::{DefId, DefIdSet};
 use rustc_middle::ty::TyCtxt;
 use rustc_session::Session;
+use rustc_session::features::StabilityExt;
 use rustc_span::def_id::LOCAL_CRATE;
 use rustdoc_json_types as types;
 // It's important to use the FxHashMap from rustdoc_json_types here, instead of
@@ -36,19 +37,18 @@ use crate::formats::cache::Cache;
 use crate::json::conversions::IntoJson;
 use crate::{clean, try_err};
 
-#[derive(Clone)]
 pub(crate) struct JsonRenderer<'tcx> {
     tcx: TyCtxt<'tcx>,
     /// A mapping of IDs that contains all local items for this crate which gets output as a top
     /// level field of the JSON blob.
-    index: Rc<RefCell<FxHashMap<types::Id, types::Item>>>,
+    index: FxHashMap<types::Id, types::Item>,
     /// The directory where the JSON blob should be written to.
     ///
     /// If this is `None`, the blob will be printed to `stdout` instead.
     out_dir: Option<PathBuf>,
     cache: Rc<Cache>,
     imported_items: DefIdSet,
-    id_interner: Rc<RefCell<ids::IdInterner>>,
+    id_interner: RefCell<ids::IdInterner>,
 }
 
 impl<'tcx> JsonRenderer<'tcx> {
@@ -65,7 +65,7 @@ impl<'tcx> JsonRenderer<'tcx> {
                     .iter()
                     .map(|i| {
                         let item = &i.impl_item;
-                        self.item(item.clone()).unwrap();
+                        self.item(item).unwrap();
                         self.id_from_item(item)
                     })
                     .collect()
@@ -96,7 +96,7 @@ impl<'tcx> JsonRenderer<'tcx> {
                         }
 
                         if item.item_id.is_local() || is_primitive_impl {
-                            self.item(item.clone()).unwrap();
+                            self.item(item).unwrap();
                             Some(self.id_from_item(item))
                         } else {
                             None
@@ -148,7 +148,7 @@ fn target(sess: &rustc_session::Session) -> types::Target {
             .copied()
             .filter(|(_, stability, _)| {
                 // Describe only target features which the user can toggle
-                stability.toggle_allowed().is_ok()
+                stability.is_toggle_permitted(sess).is_ok()
             })
             .map(|(name, stability, implied_features)| {
                 types::TargetFeature {
@@ -164,7 +164,7 @@ fn target(sess: &rustc_session::Session) -> types::Target {
                             // Imply only target features which the user can toggle
                             feature_stability
                                 .get(name)
-                                .map(|stability| stability.toggle_allowed().is_ok())
+                                .map(|stability| stability.is_toggle_permitted(sess).is_ok())
                                 .unwrap_or(false)
                         })
                         .map(String::from)
@@ -197,7 +197,7 @@ impl<'tcx> FormatRenderer<'tcx> for JsonRenderer<'tcx> {
         Ok((
             JsonRenderer {
                 tcx,
-                index: Rc::new(RefCell::new(FxHashMap::default())),
+                index: FxHashMap::default(),
                 out_dir: if options.output_to_stdout { None } else { Some(options.output) },
                 cache: Rc::new(cache),
                 imported_items,
@@ -217,7 +217,9 @@ impl<'tcx> FormatRenderer<'tcx> for JsonRenderer<'tcx> {
     /// Inserts an item into the index. This should be used rather than directly calling insert on
     /// the hashmap because certain items (traits and types) need to have their mappings for trait
     /// implementations filled out before they're inserted.
-    fn item(&mut self, item: clean::Item) -> Result<(), Error> {
+    fn item(&mut self, item: &clean::Item) -> Result<(), Error> {
+        use std::collections::hash_map::Entry;
+
         let item_type = item.type_();
         let item_name = item.name;
         trace!("rendering {item_type} {item_name:?}");
@@ -225,11 +227,11 @@ impl<'tcx> FormatRenderer<'tcx> for JsonRenderer<'tcx> {
         // Flatten items that recursively store other items. We include orphaned items from
         // stripped modules and etc that are otherwise reachable.
         if let ItemKind::StrippedItem(inner) = &item.kind {
-            inner.inner_items().for_each(|i| self.item(i.clone()).unwrap());
+            inner.inner_items().for_each(|i| self.item(i).unwrap());
         }
 
         // Flatten items that recursively store other items
-        item.kind.inner_items().for_each(|i| self.item(i.clone()).unwrap());
+        item.kind.inner_items().for_each(|i| self.item(i).unwrap());
 
         let item_id = item.item_id;
         if let Some(mut new_item) = self.convert_item(item) {
@@ -272,18 +274,25 @@ impl<'tcx> FormatRenderer<'tcx> for JsonRenderer<'tcx> {
                 | types::ItemEnum::Macro(_)
                 | types::ItemEnum::ProcMacro(_) => false,
             };
-            let removed = self.index.borrow_mut().insert(new_item.id, new_item.clone());
 
             // FIXME(adotinthevoid): Currently, the index is duplicated. This is a sanity check
             // to make sure the items are unique. The main place this happens is when an item, is
             // reexported in more than one place. See `rustdoc-json/reexport/in_root_and_mod`
-            if let Some(old_item) = removed {
-                // In case of generic implementations (like `impl<T> Trait for T {}`), all the
-                // inner items will be duplicated so we can ignore if they are slightly different.
-                if !can_be_ignored {
-                    assert_eq!(old_item, new_item);
+            match self.index.entry(new_item.id) {
+                Entry::Vacant(entry) => {
+                    entry.insert(new_item);
+                }
+                Entry::Occupied(mut entry) => {
+                    // In case of generic implementations (like `impl<T> Trait for T {}`), all the
+                    // inner items will be duplicated so we can ignore if they are slightly
+                    // different.
+                    let old_item = entry.get_mut();
+                    if !can_be_ignored {
+                        assert_eq!(*old_item, new_item);
+                    }
+                    trace!("replaced {old_item:?}\nwith {new_item:?}");
+                    *old_item = new_item;
                 }
-                trace!("replaced {old_item:?}\nwith {new_item:?}");
             }
         }
 
@@ -295,11 +304,13 @@ impl<'tcx> FormatRenderer<'tcx> for JsonRenderer<'tcx> {
         unreachable!("RUN_ON_MODULE = false, should never call mod_item_in")
     }
 
-    fn after_krate(&mut self) -> Result<(), Error> {
+    fn after_krate(mut self) -> Result<(), Error> {
         debug!("Done with crate");
 
         let e = ExternalCrate { crate_num: LOCAL_CRATE };
-        let index = (*self.index).clone().into_inner();
+
+        // We've finished using the index, and don't want to clone it, because it is big.
+        let index = std::mem::take(&mut self.index);
 
         // Note that tcx.rust_target_features is inappropriate here because rustdoc tries to run for
         // multiple targets: https://github.com/rust-lang/rust/pull/137632
@@ -324,7 +335,7 @@ impl<'tcx> FormatRenderer<'tcx> for JsonRenderer<'tcx> {
                         types::ItemSummary {
                             crate_id: k.krate.as_u32(),
                             path: path.iter().map(|s| s.to_string()).collect(),
-                            kind: kind.into_json(self),
+                            kind: kind.into_json(&self),
                         },
                     )
                 })
diff --git a/src/llvm-project b/src/llvm-project
-Subproject c1118fdbb3024157df7f4cfe765f2b0b4339e8a
+Subproject ed6566573eb21b00a3f87815e14ff766fd56ef4
diff --git a/src/rustdoc-json-types/lib.rs b/src/rustdoc-json-types/lib.rs
index 8a3ab6f8640..2c94b8f914f 100644
--- a/src/rustdoc-json-types/lib.rs
+++ b/src/rustdoc-json-types/lib.rs
@@ -30,6 +30,14 @@ pub type FxHashMap<K, V> = HashMap<K, V>; // re-export for use in src/librustdoc
 /// This integer is incremented with every breaking change to the API,
 /// and is returned along with the JSON blob as [`Crate::format_version`].
 /// Consuming code should assert that this value matches the format version(s) that it supports.
+//
+// WARNING: When you update `FORMAT_VERSION`, please also update the "Latest feature" line with a
+// description of the change. This minimizes the risk of two concurrent PRs changing
+// `FORMAT_VERSION` from N to N+1 and git merging them without conflicts; the "Latest feature" line
+// will instead cause conflicts. See #94591 for more. (This paragraph and the "Latest feature" line
+// are deliberately not in a doc comment, because they need not be in public docs.)
+//
+// Latest feature: rustdoc JSON: Don't apply #[repr] privacy heuristics
 pub const FORMAT_VERSION: u32 = 46;
 
 /// The root of the emitted JSON blob.
diff --git a/src/tools/cargo b/src/tools/cargo
-Subproject 64a12460708cf146e16cc61f28aba5dc2463bbb
+Subproject 2251525ae503fa196f6d7f9ce6d32eccb2d5f04
diff --git a/src/tools/clippy/CHANGELOG.md b/src/tools/clippy/CHANGELOG.md
index 3a98217f625..0cfe89ad378 100644
--- a/src/tools/clippy/CHANGELOG.md
+++ b/src/tools/clippy/CHANGELOG.md
@@ -5685,6 +5685,7 @@ Released 2018-09-13
 [`cmp_nan`]: https://rust-lang.github.io/rust-clippy/master/index.html#cmp_nan
 [`cmp_null`]: https://rust-lang.github.io/rust-clippy/master/index.html#cmp_null
 [`cmp_owned`]: https://rust-lang.github.io/rust-clippy/master/index.html#cmp_owned
+[`coerce_container_to_any`]: https://rust-lang.github.io/rust-clippy/master/index.html#coerce_container_to_any
 [`cognitive_complexity`]: https://rust-lang.github.io/rust-clippy/master/index.html#cognitive_complexity
 [`collapsible_else_if`]: https://rust-lang.github.io/rust-clippy/master/index.html#collapsible_else_if
 [`collapsible_if`]: https://rust-lang.github.io/rust-clippy/master/index.html#collapsible_if
@@ -5736,6 +5737,7 @@ Released 2018-09-13
 [`doc_markdown`]: https://rust-lang.github.io/rust-clippy/master/index.html#doc_markdown
 [`doc_nested_refdefs`]: https://rust-lang.github.io/rust-clippy/master/index.html#doc_nested_refdefs
 [`doc_overindented_list_items`]: https://rust-lang.github.io/rust-clippy/master/index.html#doc_overindented_list_items
+[`doc_suspicious_footnotes`]: https://rust-lang.github.io/rust-clippy/master/index.html#doc_suspicious_footnotes
 [`double_comparisons`]: https://rust-lang.github.io/rust-clippy/master/index.html#double_comparisons
 [`double_ended_iterator_last`]: https://rust-lang.github.io/rust-clippy/master/index.html#double_ended_iterator_last
 [`double_must_use`]: https://rust-lang.github.io/rust-clippy/master/index.html#double_must_use
@@ -5862,6 +5864,7 @@ Released 2018-09-13
 [`ineffective_open_options`]: https://rust-lang.github.io/rust-clippy/master/index.html#ineffective_open_options
 [`inefficient_to_string`]: https://rust-lang.github.io/rust-clippy/master/index.html#inefficient_to_string
 [`infallible_destructuring_match`]: https://rust-lang.github.io/rust-clippy/master/index.html#infallible_destructuring_match
+[`infallible_try_from`]: https://rust-lang.github.io/rust-clippy/master/index.html#infallible_try_from
 [`infinite_iter`]: https://rust-lang.github.io/rust-clippy/master/index.html#infinite_iter
 [`infinite_loop`]: https://rust-lang.github.io/rust-clippy/master/index.html#infinite_loop
 [`inherent_to_string`]: https://rust-lang.github.io/rust-clippy/master/index.html#inherent_to_string
@@ -5888,6 +5891,7 @@ Released 2018-09-13
 [`inverted_saturating_sub`]: https://rust-lang.github.io/rust-clippy/master/index.html#inverted_saturating_sub
 [`invisible_characters`]: https://rust-lang.github.io/rust-clippy/master/index.html#invisible_characters
 [`io_other_error`]: https://rust-lang.github.io/rust-clippy/master/index.html#io_other_error
+[`ip_constant`]: https://rust-lang.github.io/rust-clippy/master/index.html#ip_constant
 [`is_digit_ascii_radix`]: https://rust-lang.github.io/rust-clippy/master/index.html#is_digit_ascii_radix
 [`items_after_statements`]: https://rust-lang.github.io/rust-clippy/master/index.html#items_after_statements
 [`items_after_test_module`]: https://rust-lang.github.io/rust-clippy/master/index.html#items_after_test_module
@@ -6163,6 +6167,7 @@ Released 2018-09-13
 [`pathbuf_init_then_push`]: https://rust-lang.github.io/rust-clippy/master/index.html#pathbuf_init_then_push
 [`pattern_type_mismatch`]: https://rust-lang.github.io/rust-clippy/master/index.html#pattern_type_mismatch
 [`permissions_set_readonly_false`]: https://rust-lang.github.io/rust-clippy/master/index.html#permissions_set_readonly_false
+[`pointer_format`]: https://rust-lang.github.io/rust-clippy/master/index.html#pointer_format
 [`pointers_in_nomem_asm_block`]: https://rust-lang.github.io/rust-clippy/master/index.html#pointers_in_nomem_asm_block
 [`positional_named_format_parameters`]: https://rust-lang.github.io/rust-clippy/master/index.html#positional_named_format_parameters
 [`possible_missing_comma`]: https://rust-lang.github.io/rust-clippy/master/index.html#possible_missing_comma
diff --git a/src/tools/clippy/clippy_dev/src/update_lints.rs b/src/tools/clippy/clippy_dev/src/update_lints.rs
index 320462a2c96..08592f2521f 100644
--- a/src/tools/clippy/clippy_dev/src/update_lints.rs
+++ b/src/tools/clippy/clippy_dev/src/update_lints.rs
@@ -73,8 +73,8 @@ pub fn generate_lint_files(
             (
                 "clippy_lints/src/lib.rs",
                 &mut update_text_region_fn(
-                    "// begin lints modules, do not remove this comment, it’s used in `update_lints`\n",
-                    "// end lints modules, do not remove this comment, it’s used in `update_lints`",
+                    "// begin lints modules, do not remove this comment, it's used in `update_lints`\n",
+                    "// end lints modules, do not remove this comment, it's used in `update_lints`",
                     |dst| {
                         for lint_mod in lints.iter().map(|l| &l.module).sorted().dedup() {
                             writeln!(dst, "mod {lint_mod};").unwrap();
diff --git a/src/tools/clippy/clippy_lints/src/arbitrary_source_item_ordering.rs b/src/tools/clippy/clippy_lints/src/arbitrary_source_item_ordering.rs
index 59a0c7c8868..b9ae9afe851 100644
--- a/src/tools/clippy/clippy_lints/src/arbitrary_source_item_ordering.rs
+++ b/src/tools/clippy/clippy_lints/src/arbitrary_source_item_ordering.rs
@@ -204,7 +204,7 @@ impl ArbitrarySourceItemOrdering {
                 self.assoc_types_order
             ),
             Some(before_item.span),
-            format!("should be placed before `{}`", before_item.ident.as_str(),),
+            format!("should be placed before `{}`", before_item.ident.name),
         );
     }
 
@@ -216,7 +216,7 @@ impl ArbitrarySourceItemOrdering {
             ident.span,
             "incorrect ordering of items (must be alphabetically ordered)",
             Some(before_ident.span),
-            format!("should be placed before `{}`", before_ident.as_str(),),
+            format!("should be placed before `{}`", before_ident.name),
         );
     }
 
@@ -228,7 +228,7 @@ impl ArbitrarySourceItemOrdering {
         };
 
         let (before_span, note) = if let Some(ident) = before_item.kind.ident() {
-            (ident.span, format!("should be placed before `{}`", ident.as_str(),))
+            (ident.span, format!("should be placed before `{}`", ident.name))
         } else {
             (
                 before_item.span,
@@ -255,7 +255,7 @@ impl ArbitrarySourceItemOrdering {
                 self.assoc_types_order
             ),
             Some(before_item.span),
-            format!("should be placed before `{}`", before_item.ident.as_str(),),
+            format!("should be placed before `{}`", before_item.ident.name),
         );
     }
 }
diff --git a/src/tools/clippy/clippy_lints/src/attrs/deprecated_cfg_attr.rs b/src/tools/clippy/clippy_lints/src/attrs/deprecated_cfg_attr.rs
index 0edb50be8c7..d67a194b020 100644
--- a/src/tools/clippy/clippy_lints/src/attrs/deprecated_cfg_attr.rs
+++ b/src/tools/clippy/clippy_lints/src/attrs/deprecated_cfg_attr.rs
@@ -61,7 +61,7 @@ pub(super) fn check_clippy(cx: &EarlyContext<'_>, attr: &Attribute) {
 
 fn check_deprecated_cfg_recursively(cx: &EarlyContext<'_>, attr: &rustc_ast::MetaItem) {
     if let Some(ident) = attr.ident() {
-        if ["any", "all", "not"].contains(&ident.name.as_str()) {
+        if matches!(ident.name, sym::any | sym::all | sym::not) {
             let Some(list) = attr.meta_item_list() else { return };
             for item in list.iter().filter_map(|item| item.meta_item()) {
                 check_deprecated_cfg_recursively(cx, item);
diff --git a/src/tools/clippy/clippy_lints/src/attrs/duplicated_attributes.rs b/src/tools/clippy/clippy_lints/src/attrs/duplicated_attributes.rs
index a851daaede7..c2406bcfb64 100644
--- a/src/tools/clippy/clippy_lints/src/attrs/duplicated_attributes.rs
+++ b/src/tools/clippy/clippy_lints/src/attrs/duplicated_attributes.rs
@@ -1,9 +1,10 @@
 use super::DUPLICATED_ATTRIBUTES;
 use clippy_utils::diagnostics::span_lint_and_then;
+use itertools::Itertools;
 use rustc_ast::{Attribute, MetaItem};
 use rustc_data_structures::fx::FxHashMap;
 use rustc_lint::EarlyContext;
-use rustc_span::{Span, sym};
+use rustc_span::{Span, Symbol, sym};
 use std::collections::hash_map::Entry;
 
 fn emit_if_duplicated(
@@ -29,7 +30,7 @@ fn check_duplicated_attr(
     cx: &EarlyContext<'_>,
     attr: &MetaItem,
     attr_paths: &mut FxHashMap<String, Span>,
-    parent: &mut Vec<String>,
+    parent: &mut Vec<Symbol>,
 ) {
     if attr.span.from_expansion() {
         return;
@@ -43,7 +44,7 @@ fn check_duplicated_attr(
         return;
     }
     if let Some(direct_parent) = parent.last()
-        && direct_parent == sym::cfg_trace.as_str()
+        && *direct_parent == sym::cfg_trace
         && [sym::all, sym::not, sym::any].contains(&name)
     {
         // FIXME: We don't correctly check `cfg`s for now, so if it's more complex than just a one
@@ -51,9 +52,14 @@ fn check_duplicated_attr(
         return;
     }
     if let Some(value) = attr.value_str() {
-        emit_if_duplicated(cx, attr, attr_paths, format!("{}:{name}={value}", parent.join(":")));
+        emit_if_duplicated(
+            cx,
+            attr,
+            attr_paths,
+            format!("{}:{name}={value}", parent.iter().join(":")),
+        );
     } else if let Some(sub_attrs) = attr.meta_item_list() {
-        parent.push(name.as_str().to_string());
+        parent.push(name);
         for sub_attr in sub_attrs {
             if let Some(meta) = sub_attr.meta_item() {
                 check_duplicated_attr(cx, meta, attr_paths, parent);
@@ -61,7 +67,7 @@ fn check_duplicated_attr(
         }
         parent.pop();
     } else {
-        emit_if_duplicated(cx, attr, attr_paths, format!("{}:{name}", parent.join(":")));
+        emit_if_duplicated(cx, attr, attr_paths, format!("{}:{name}", parent.iter().join(":")));
     }
 }
 
diff --git a/src/tools/clippy/clippy_lints/src/booleans.rs b/src/tools/clippy/clippy_lints/src/booleans.rs
index 7c6fd91ca67..bf43234ff50 100644
--- a/src/tools/clippy/clippy_lints/src/booleans.rs
+++ b/src/tools/clippy/clippy_lints/src/booleans.rs
@@ -1,10 +1,10 @@
 use clippy_config::Conf;
 use clippy_utils::diagnostics::{span_lint_and_sugg, span_lint_hir_and_then};
-use clippy_utils::eq_expr_value;
 use clippy_utils::msrvs::{self, Msrv};
 use clippy_utils::source::SpanRangeExt;
 use clippy_utils::sugg::Sugg;
 use clippy_utils::ty::{implements_trait, is_type_diagnostic_item};
+use clippy_utils::{eq_expr_value, sym};
 use rustc_ast::ast::LitKind;
 use rustc_attr_data_structures::RustcVersion;
 use rustc_errors::Applicability;
@@ -13,7 +13,7 @@ use rustc_hir::{BinOpKind, Body, Expr, ExprKind, FnDecl, UnOp};
 use rustc_lint::{LateContext, LateLintPass, Level};
 use rustc_session::impl_lint_pass;
 use rustc_span::def_id::LocalDefId;
-use rustc_span::{Span, SyntaxContext, sym};
+use rustc_span::{Span, Symbol, SyntaxContext};
 
 declare_clippy_lint! {
     /// ### What it does
@@ -73,10 +73,10 @@ declare_clippy_lint! {
 }
 
 // For each pairs, both orders are considered.
-const METHODS_WITH_NEGATION: [(Option<RustcVersion>, &str, &str); 3] = [
-    (None, "is_some", "is_none"),
-    (None, "is_err", "is_ok"),
-    (Some(msrvs::IS_NONE_OR), "is_some_and", "is_none_or"),
+const METHODS_WITH_NEGATION: [(Option<RustcVersion>, Symbol, Symbol); 3] = [
+    (None, sym::is_some, sym::is_none),
+    (None, sym::is_err, sym::is_ok),
+    (Some(msrvs::IS_NONE_OR), sym::is_some_and, sym::is_none_or),
 ];
 
 pub struct NonminimalBool {
@@ -440,9 +440,7 @@ fn simplify_not(cx: &LateContext<'_>, curr_msrv: Msrv, expr: &Expr<'_>) -> Optio
                 .iter()
                 .copied()
                 .flat_map(|(msrv, a, b)| vec![(msrv, a, b), (msrv, b, a)])
-                .find(|&(msrv, a, _)| {
-                    a == path.ident.name.as_str() && msrv.is_none_or(|msrv| curr_msrv.meets(cx, msrv))
-                })
+                .find(|&(msrv, a, _)| a == path.ident.name && msrv.is_none_or(|msrv| curr_msrv.meets(cx, msrv)))
                 .and_then(|(_, _, neg_method)| {
                     let negated_args = args
                         .iter()
diff --git a/src/tools/clippy/clippy_lints/src/casts/cast_lossless.rs b/src/tools/clippy/clippy_lints/src/casts/cast_lossless.rs
index 0f066fae118..c1d6cec1b62 100644
--- a/src/tools/clippy/clippy_lints/src/casts/cast_lossless.rs
+++ b/src/tools/clippy/clippy_lints/src/casts/cast_lossless.rs
@@ -76,19 +76,20 @@ fn should_lint(cx: &LateContext<'_>, cast_from: Ty<'_>, cast_to: Ty<'_>, msrv: M
         return false;
     }
 
-    match (cast_from.is_integral(), cast_to.is_integral()) {
-        (true, true) => {
+    match (
+        utils::int_ty_to_nbits(cx.tcx, cast_from),
+        utils::int_ty_to_nbits(cx.tcx, cast_to),
+    ) {
+        (Some(from_nbits), Some(to_nbits)) => {
             let cast_signed_to_unsigned = cast_from.is_signed() && !cast_to.is_signed();
-            let from_nbits = utils::int_ty_to_nbits(cast_from, cx.tcx);
-            let to_nbits = utils::int_ty_to_nbits(cast_to, cx.tcx);
             !is_isize_or_usize(cast_from)
                 && !is_isize_or_usize(cast_to)
                 && from_nbits < to_nbits
                 && !cast_signed_to_unsigned
         },
 
-        (true, false) => {
-            let from_nbits = utils::int_ty_to_nbits(cast_from, cx.tcx);
+        (Some(from_nbits), None) => {
+            // FIXME: handle `f16` and `f128`
             let to_nbits = if let ty::Float(FloatTy::F32) = cast_to.kind() {
                 32
             } else {
@@ -96,9 +97,7 @@ fn should_lint(cx: &LateContext<'_>, cast_from: Ty<'_>, cast_to: Ty<'_>, msrv: M
             };
             !is_isize_or_usize(cast_from) && from_nbits < to_nbits
         },
-        (false, true) if matches!(cast_from.kind(), ty::Bool) && msrv.meets(cx, msrvs::FROM_BOOL) => true,
-        (_, _) => {
-            matches!(cast_from.kind(), ty::Float(FloatTy::F32)) && matches!(cast_to.kind(), ty::Float(FloatTy::F64))
-        },
+        (None, Some(_)) if cast_from.is_bool() && msrv.meets(cx, msrvs::FROM_BOOL) => true,
+        _ => matches!(cast_from.kind(), ty::Float(FloatTy::F32)) && matches!(cast_to.kind(), ty::Float(FloatTy::F64)),
     }
 }
diff --git a/src/tools/clippy/clippy_lints/src/casts/cast_possible_truncation.rs b/src/tools/clippy/clippy_lints/src/casts/cast_possible_truncation.rs
index 4120e5c8cb7..a2ecb5fb44a 100644
--- a/src/tools/clippy/clippy_lints/src/casts/cast_possible_truncation.rs
+++ b/src/tools/clippy/clippy_lints/src/casts/cast_possible_truncation.rs
@@ -91,15 +91,14 @@ pub(super) fn check(
     cast_to: Ty<'_>,
     cast_to_span: Span,
 ) {
-    let msg = match (cast_from.kind(), cast_to.is_integral()) {
-        (ty::Int(_) | ty::Uint(_), true) => {
+    let msg = match (cast_from.kind(), utils::int_ty_to_nbits(cx.tcx, cast_to)) {
+        (ty::Int(_) | ty::Uint(_), Some(to_nbits)) => {
             let from_nbits = apply_reductions(
                 cx,
-                utils::int_ty_to_nbits(cast_from, cx.tcx),
+                utils::int_ty_to_nbits(cx.tcx, cast_from).unwrap(),
                 cast_expr,
                 cast_from.is_signed(),
             );
-            let to_nbits = utils::int_ty_to_nbits(cast_to, cx.tcx);
 
             let (should_lint, suffix) = match (is_isize_or_usize(cast_from), is_isize_or_usize(cast_to)) {
                 (true, true) | (false, false) => (to_nbits < from_nbits, ""),
@@ -121,7 +120,7 @@ pub(super) fn check(
             format!("casting `{cast_from}` to `{cast_to}` may truncate the value{suffix}",)
         },
 
-        (ty::Adt(def, _), true) if def.is_enum() => {
+        (ty::Adt(def, _), Some(to_nbits)) if def.is_enum() => {
             let (from_nbits, variant) = if let ExprKind::Path(p) = &cast_expr.kind
                 && let Res::Def(DefKind::Ctor(..), id) = cx.qpath_res(p, cast_expr.hir_id)
             {
@@ -132,7 +131,6 @@ pub(super) fn check(
             } else {
                 (utils::enum_ty_to_nbits(*def, cx.tcx), None)
             };
-            let to_nbits = utils::int_ty_to_nbits(cast_to, cx.tcx);
 
             let cast_from_ptr_size = def.repr().int.is_none_or(|ty| matches!(ty, IntegerType::Pointer(_),));
             let suffix = match (cast_from_ptr_size, is_isize_or_usize(cast_to)) {
@@ -157,11 +155,11 @@ pub(super) fn check(
             format!("casting `{cast_from}` to `{cast_to}` may truncate the value{suffix}")
         },
 
-        (ty::Float(_), true) => {
+        (ty::Float(_), Some(_)) => {
             format!("casting `{cast_from}` to `{cast_to}` may truncate the value")
         },
 
-        (ty::Float(FloatTy::F64), false) if matches!(cast_to.kind(), &ty::Float(FloatTy::F32)) => {
+        (ty::Float(FloatTy::F64), None) if matches!(cast_to.kind(), &ty::Float(FloatTy::F32)) => {
             "casting `f64` to `f32` may truncate the value".to_string()
         },
 
diff --git a/src/tools/clippy/clippy_lints/src/casts/cast_possible_wrap.rs b/src/tools/clippy/clippy_lints/src/casts/cast_possible_wrap.rs
index 504d0a267e4..e26c03ccda9 100644
--- a/src/tools/clippy/clippy_lints/src/casts/cast_possible_wrap.rs
+++ b/src/tools/clippy/clippy_lints/src/casts/cast_possible_wrap.rs
@@ -17,9 +17,12 @@ enum EmitState {
 }
 
 pub(super) fn check(cx: &LateContext<'_>, expr: &Expr<'_>, cast_from: Ty<'_>, cast_to: Ty<'_>) {
-    if !(cast_from.is_integral() && cast_to.is_integral()) {
+    let (Some(from_nbits), Some(to_nbits)) = (
+        utils::int_ty_to_nbits(cx.tcx, cast_from),
+        utils::int_ty_to_nbits(cx.tcx, cast_to),
+    ) else {
         return;
-    }
+    };
 
     // emit a lint if a cast is:
     // 1. unsigned to signed
@@ -35,9 +38,6 @@ pub(super) fn check(cx: &LateContext<'_>, expr: &Expr<'_>, cast_from: Ty<'_>, ca
         return;
     }
 
-    let from_nbits = utils::int_ty_to_nbits(cast_from, cx.tcx);
-    let to_nbits = utils::int_ty_to_nbits(cast_to, cx.tcx);
-
     let should_lint = match (cast_from.is_ptr_sized_integral(), cast_to.is_ptr_sized_integral()) {
         (true, true) => {
             // casts between two ptr sized integers are trivially always the same size
diff --git a/src/tools/clippy/clippy_lints/src/casts/cast_precision_loss.rs b/src/tools/clippy/clippy_lints/src/casts/cast_precision_loss.rs
index 1eb115ce6bd..712e38db499 100644
--- a/src/tools/clippy/clippy_lints/src/casts/cast_precision_loss.rs
+++ b/src/tools/clippy/clippy_lints/src/casts/cast_precision_loss.rs
@@ -7,15 +7,14 @@ use rustc_middle::ty::{self, FloatTy, Ty};
 use super::{CAST_PRECISION_LOSS, utils};
 
 pub(super) fn check(cx: &LateContext<'_>, expr: &Expr<'_>, cast_from: Ty<'_>, cast_to: Ty<'_>) {
-    if !cast_from.is_integral() || cast_to.is_integral() {
+    let Some(from_nbits) = utils::int_ty_to_nbits(cx.tcx, cast_from) else {
         return;
-    }
+    };
 
-    let from_nbits = utils::int_ty_to_nbits(cast_from, cx.tcx);
-    let to_nbits = if cast_to.kind() == &ty::Float(FloatTy::F32) {
-        32
-    } else {
-        64
+    // FIXME: handle `f16` and `f128`
+    let to_nbits = match cast_to.kind() {
+        ty::Float(f @ (FloatTy::F32 | FloatTy::F64)) => f.bit_width(),
+        _ => return,
     };
 
     if !(is_isize_or_usize(cast_from) || from_nbits >= to_nbits) {
@@ -29,9 +28,10 @@ pub(super) fn check(cx: &LateContext<'_>, expr: &Expr<'_>, cast_from: Ty<'_>, ca
     let from_nbits_str = if arch_dependent {
         "64".to_owned()
     } else if is_isize_or_usize(cast_from) {
+        // FIXME: handle 16 bits `usize` type
         "32 or 64".to_owned()
     } else {
-        utils::int_ty_to_nbits(cast_from, cx.tcx).to_string()
+        from_nbits.to_string()
     };
 
     span_lint(
diff --git a/src/tools/clippy/clippy_lints/src/casts/cast_ptr_alignment.rs b/src/tools/clippy/clippy_lints/src/casts/cast_ptr_alignment.rs
index 01020f3eee2..e4dafde0f9d 100644
--- a/src/tools/clippy/clippy_lints/src/casts/cast_ptr_alignment.rs
+++ b/src/tools/clippy/clippy_lints/src/casts/cast_ptr_alignment.rs
@@ -61,7 +61,7 @@ fn is_used_as_unaligned(cx: &LateContext<'_>, e: &Expr<'_>) -> bool {
     };
     match parent.kind {
         ExprKind::MethodCall(name, self_arg, ..) if self_arg.hir_id == e.hir_id => {
-            if matches!(name.ident.as_str(), "read_unaligned" | "write_unaligned")
+            if matches!(name.ident.name, sym::read_unaligned | sym::write_unaligned)
                 && let Some(def_id) = cx.typeck_results().type_dependent_def_id(parent.hir_id)
                 && let Some(def_id) = cx.tcx.impl_of_method(def_id)
                 && cx.tcx.type_of(def_id).instantiate_identity().is_raw_ptr()
diff --git a/src/tools/clippy/clippy_lints/src/casts/fn_to_numeric_cast.rs b/src/tools/clippy/clippy_lints/src/casts/fn_to_numeric_cast.rs
index ac1a355c8d9..105477093b5 100644
--- a/src/tools/clippy/clippy_lints/src/casts/fn_to_numeric_cast.rs
+++ b/src/tools/clippy/clippy_lints/src/casts/fn_to_numeric_cast.rs
@@ -3,24 +3,22 @@ use clippy_utils::source::snippet_with_applicability;
 use rustc_errors::Applicability;
 use rustc_hir::Expr;
 use rustc_lint::LateContext;
-use rustc_middle::ty::{self, Ty, UintTy};
+use rustc_middle::ty::{self, Ty};
 
 use super::{FN_TO_NUMERIC_CAST, utils};
 
 pub(super) fn check(cx: &LateContext<'_>, expr: &Expr<'_>, cast_expr: &Expr<'_>, cast_from: Ty<'_>, cast_to: Ty<'_>) {
     // We only want to check casts to `ty::Uint` or `ty::Int`
-    match cast_to.kind() {
-        ty::Uint(_) | ty::Int(..) => { /* continue on */ },
-        _ => return,
-    }
+    let Some(to_nbits) = utils::int_ty_to_nbits(cx.tcx, cast_to) else {
+        return;
+    };
 
     match cast_from.kind() {
         ty::FnDef(..) | ty::FnPtr(..) => {
             let mut applicability = Applicability::MaybeIncorrect;
-            let from_snippet = snippet_with_applicability(cx, cast_expr.span, "x", &mut applicability);
-            let to_nbits = utils::int_ty_to_nbits(cast_to, cx.tcx);
 
-            if (to_nbits >= cx.tcx.data_layout.pointer_size.bits()) && (*cast_to.kind() != ty::Uint(UintTy::Usize)) {
+            if to_nbits >= cx.tcx.data_layout.pointer_size.bits() && !cast_to.is_usize() {
+                let from_snippet = snippet_with_applicability(cx, cast_expr.span, "x", &mut applicability);
                 span_lint_and_sugg(
                     cx,
                     FN_TO_NUMERIC_CAST,
diff --git a/src/tools/clippy/clippy_lints/src/casts/fn_to_numeric_cast_with_truncation.rs b/src/tools/clippy/clippy_lints/src/casts/fn_to_numeric_cast_with_truncation.rs
index 18e7798452e..700b7d0d426 100644
--- a/src/tools/clippy/clippy_lints/src/casts/fn_to_numeric_cast_with_truncation.rs
+++ b/src/tools/clippy/clippy_lints/src/casts/fn_to_numeric_cast_with_truncation.rs
@@ -9,16 +9,14 @@ use super::{FN_TO_NUMERIC_CAST_WITH_TRUNCATION, utils};
 
 pub(super) fn check(cx: &LateContext<'_>, expr: &Expr<'_>, cast_expr: &Expr<'_>, cast_from: Ty<'_>, cast_to: Ty<'_>) {
     // We only want to check casts to `ty::Uint` or `ty::Int`
-    match cast_to.kind() {
-        ty::Uint(_) | ty::Int(..) => { /* continue on */ },
-        _ => return,
-    }
+    let Some(to_nbits) = utils::int_ty_to_nbits(cx.tcx, cast_to) else {
+        return;
+    };
     match cast_from.kind() {
         ty::FnDef(..) | ty::FnPtr(..) => {
             let mut applicability = Applicability::MaybeIncorrect;
             let from_snippet = snippet_with_applicability(cx, cast_expr.span, "x", &mut applicability);
 
-            let to_nbits = utils::int_ty_to_nbits(cast_to, cx.tcx);
             if to_nbits < cx.tcx.data_layout.pointer_size.bits() {
                 span_lint_and_sugg(
                     cx,
diff --git a/src/tools/clippy/clippy_lints/src/casts/unnecessary_cast.rs b/src/tools/clippy/clippy_lints/src/casts/unnecessary_cast.rs
index 8e8c55cf383..010f09d4c1d 100644
--- a/src/tools/clippy/clippy_lints/src/casts/unnecessary_cast.rs
+++ b/src/tools/clippy/clippy_lints/src/casts/unnecessary_cast.rs
@@ -185,7 +185,7 @@ pub(super) fn check<'tcx>(
             Node::Expr(parent) if is_borrow_expr(cx, parent) && !is_in_allowed_macro(cx, parent) => {
                 MaybeParenOrBlock::Block
             },
-            Node::Expr(parent) if cast_expr.precedence() < parent.precedence() => MaybeParenOrBlock::Paren,
+            Node::Expr(parent) if cx.precedence(cast_expr) < cx.precedence(parent) => MaybeParenOrBlock::Paren,
             _ => MaybeParenOrBlock::Nothing,
         };
 
diff --git a/src/tools/clippy/clippy_lints/src/casts/utils.rs b/src/tools/clippy/clippy_lints/src/casts/utils.rs
index 5ccba92a0af..318a1646477 100644
--- a/src/tools/clippy/clippy_lints/src/casts/utils.rs
+++ b/src/tools/clippy/clippy_lints/src/casts/utils.rs
@@ -1,27 +1,14 @@
 use clippy_utils::ty::{EnumValue, read_explicit_enum_value};
 use rustc_middle::ty::{self, AdtDef, IntTy, Ty, TyCtxt, UintTy, VariantDiscr};
 
-/// Returns the size in bits of an integral type.
-/// Will return 0 if the type is not an int or uint variant
-pub(super) fn int_ty_to_nbits(typ: Ty<'_>, tcx: TyCtxt<'_>) -> u64 {
-    match typ.kind() {
-        ty::Int(i) => match i {
-            IntTy::Isize => tcx.data_layout.pointer_size.bits(),
-            IntTy::I8 => 8,
-            IntTy::I16 => 16,
-            IntTy::I32 => 32,
-            IntTy::I64 => 64,
-            IntTy::I128 => 128,
-        },
-        ty::Uint(i) => match i {
-            UintTy::Usize => tcx.data_layout.pointer_size.bits(),
-            UintTy::U8 => 8,
-            UintTy::U16 => 16,
-            UintTy::U32 => 32,
-            UintTy::U64 => 64,
-            UintTy::U128 => 128,
-        },
-        _ => 0,
+/// Returns the size in bits of an integral type, or `None` if `ty` is not an
+/// integral type.
+pub(super) fn int_ty_to_nbits(tcx: TyCtxt<'_>, ty: Ty<'_>) -> Option<u64> {
+    match ty.kind() {
+        ty::Int(IntTy::Isize) | ty::Uint(UintTy::Usize) => Some(tcx.data_layout.pointer_size.bits()),
+        ty::Int(i) => i.bit_width(),
+        ty::Uint(i) => i.bit_width(),
+        _ => None,
     }
 }
 
diff --git a/src/tools/clippy/clippy_lints/src/checked_conversions.rs b/src/tools/clippy/clippy_lints/src/checked_conversions.rs
index 8ada608049c..9b3822f9d8f 100644
--- a/src/tools/clippy/clippy_lints/src/checked_conversions.rs
+++ b/src/tools/clippy/clippy_lints/src/checked_conversions.rs
@@ -2,11 +2,12 @@ use clippy_config::Conf;
 use clippy_utils::diagnostics::span_lint_and_sugg;
 use clippy_utils::msrvs::{self, Msrv};
 use clippy_utils::source::snippet_with_applicability;
-use clippy_utils::{SpanlessEq, is_in_const_context, is_integer_literal};
+use clippy_utils::{SpanlessEq, is_in_const_context, is_integer_literal, sym};
 use rustc_errors::Applicability;
 use rustc_hir::{BinOpKind, Expr, ExprKind, QPath, TyKind};
 use rustc_lint::{LateContext, LateLintPass, LintContext};
 use rustc_session::impl_lint_pass;
+use rustc_span::Symbol;
 
 declare_clippy_lint! {
     /// ### What it does
@@ -98,7 +99,7 @@ impl LateLintPass<'_> for CheckedConversions {
 struct Conversion<'a> {
     cvt: ConversionType,
     expr_to_cast: &'a Expr<'a>,
-    to_type: Option<&'a str>,
+    to_type: Option<Symbol>,
 }
 
 /// The kind of conversion that is checked
@@ -150,7 +151,7 @@ impl<'a> Conversion<'a> {
     }
 
     /// Try to construct a new conversion if the conversion type is valid
-    fn try_new(expr_to_cast: &'a Expr<'_>, from_type: &str, to_type: &'a str) -> Option<Conversion<'a>> {
+    fn try_new(expr_to_cast: &'a Expr<'_>, from_type: Symbol, to_type: Symbol) -> Option<Conversion<'a>> {
         ConversionType::try_new(from_type, to_type).map(|cvt| Conversion {
             cvt,
             expr_to_cast,
@@ -171,7 +172,7 @@ impl<'a> Conversion<'a> {
 impl ConversionType {
     /// Creates a conversion type if the type is allowed & conversion is valid
     #[must_use]
-    fn try_new(from: &str, to: &str) -> Option<Self> {
+    fn try_new(from: Symbol, to: Symbol) -> Option<Self> {
         if UINTS.contains(&from) {
             Some(Self::FromUnsigned)
         } else if SINTS.contains(&from) {
@@ -190,7 +191,7 @@ impl ConversionType {
 
 /// Check for `expr <= (to_type::MAX as from_type)`
 fn check_upper_bound<'tcx>(lt: &'tcx Expr<'tcx>, gt: &'tcx Expr<'tcx>) -> Option<Conversion<'tcx>> {
-    if let Some((from, to)) = get_types_from_cast(gt, INTS, "max_value", "MAX") {
+    if let Some((from, to)) = get_types_from_cast(gt, INTS, sym::max_value, sym::MAX) {
         Conversion::try_new(lt, from, to)
     } else {
         None
@@ -209,7 +210,7 @@ fn check_lower_bound_zero<'a>(candidate: &'a Expr<'_>, check: &'a Expr<'_>) -> O
 
 /// Check for `expr >= (to_type::MIN as from_type)`
 fn check_lower_bound_min<'a>(candidate: &'a Expr<'_>, check: &'a Expr<'_>) -> Option<Conversion<'a>> {
-    if let Some((from, to)) = get_types_from_cast(check, SINTS, "min_value", "MIN") {
+    if let Some((from, to)) = get_types_from_cast(check, SINTS, sym::min_value, sym::MIN) {
         Conversion::try_new(candidate, from, to)
     } else {
         None
@@ -217,15 +218,15 @@ fn check_lower_bound_min<'a>(candidate: &'a Expr<'_>, check: &'a Expr<'_>) -> Op
 }
 
 /// Tries to extract the from- and to-type from a cast expression
-fn get_types_from_cast<'a>(
-    expr: &'a Expr<'_>,
-    types: &'a [&str],
-    func: &'a str,
-    assoc_const: &'a str,
-) -> Option<(&'a str, &'a str)> {
+fn get_types_from_cast(
+    expr: &Expr<'_>,
+    types: &[Symbol],
+    func: Symbol,
+    assoc_const: Symbol,
+) -> Option<(Symbol, Symbol)> {
     // `to_type::max_value() as from_type`
     // or `to_type::MAX as from_type`
-    let call_from_cast: Option<(&Expr<'_>, &str)> = if let ExprKind::Cast(limit, from_type) = &expr.kind
+    let call_from_cast: Option<(&Expr<'_>, Symbol)> = if let ExprKind::Cast(limit, from_type) = &expr.kind
         // to_type::max_value(), from_type
         && let TyKind::Path(from_type_path) = &from_type.kind
         && let Some(from_sym) = int_ty_to_sym(from_type_path)
@@ -236,12 +237,12 @@ fn get_types_from_cast<'a>(
     };
 
     // `from_type::from(to_type::max_value())`
-    let limit_from: Option<(&Expr<'_>, &str)> = call_from_cast.or_else(|| {
+    let limit_from: Option<(&Expr<'_>, Symbol)> = call_from_cast.or_else(|| {
         if let ExprKind::Call(from_func, [limit]) = &expr.kind
             // `from_type::from, to_type::max_value()`
             // `from_type::from`
             && let ExprKind::Path(path) = &from_func.kind
-            && let Some(from_sym) = get_implementing_type(path, INTS, "from")
+            && let Some(from_sym) = get_implementing_type(path, INTS, sym::from)
         {
             Some((limit, from_sym))
         } else {
@@ -273,32 +274,41 @@ fn get_types_from_cast<'a>(
 }
 
 /// Gets the type which implements the called function
-fn get_implementing_type<'a>(path: &QPath<'_>, candidates: &'a [&str], function: &str) -> Option<&'a str> {
+fn get_implementing_type(path: &QPath<'_>, candidates: &[Symbol], function: Symbol) -> Option<Symbol> {
     if let QPath::TypeRelative(ty, path) = &path
-        && path.ident.name.as_str() == function
+        && path.ident.name == function
         && let TyKind::Path(QPath::Resolved(None, tp)) = &ty.kind
         && let [int] = tp.segments
     {
-        let name = int.ident.name.as_str();
-        candidates.iter().find(|c| &name == *c).copied()
+        candidates.iter().find(|c| int.ident.name == **c).copied()
     } else {
         None
     }
 }
 
 /// Gets the type as a string, if it is a supported integer
-fn int_ty_to_sym<'tcx>(path: &QPath<'_>) -> Option<&'tcx str> {
+fn int_ty_to_sym(path: &QPath<'_>) -> Option<Symbol> {
     if let QPath::Resolved(_, path) = *path
         && let [ty] = path.segments
     {
-        let name = ty.ident.name.as_str();
-        INTS.iter().find(|c| &name == *c).copied()
+        INTS.iter().find(|c| ty.ident.name == **c).copied()
     } else {
         None
     }
 }
 
 // Constants
-const UINTS: &[&str] = &["u8", "u16", "u32", "u64", "usize"];
-const SINTS: &[&str] = &["i8", "i16", "i32", "i64", "isize"];
-const INTS: &[&str] = &["u8", "u16", "u32", "u64", "usize", "i8", "i16", "i32", "i64", "isize"];
+const UINTS: &[Symbol] = &[sym::u8, sym::u16, sym::u32, sym::u64, sym::usize];
+const SINTS: &[Symbol] = &[sym::i8, sym::i16, sym::i32, sym::i64, sym::isize];
+const INTS: &[Symbol] = &[
+    sym::u8,
+    sym::u16,
+    sym::u32,
+    sym::u64,
+    sym::usize,
+    sym::i8,
+    sym::i16,
+    sym::i32,
+    sym::i64,
+    sym::isize,
+];
diff --git a/src/tools/clippy/clippy_lints/src/cloned_ref_to_slice_refs.rs b/src/tools/clippy/clippy_lints/src/cloned_ref_to_slice_refs.rs
index 6b239a1541b..e33a8e0fb74 100644
--- a/src/tools/clippy/clippy_lints/src/cloned_ref_to_slice_refs.rs
+++ b/src/tools/clippy/clippy_lints/src/cloned_ref_to_slice_refs.rs
@@ -17,7 +17,7 @@ declare_clippy_lint! {
     ///
     /// ### Why is this bad
     ///
-    /// A reference does not need to be owned in order to used as a slice.
+    /// A reference does not need to be owned in order to be used as a slice.
     ///
     /// ### Known problems
     ///
diff --git a/src/tools/clippy/clippy_lints/src/coerce_container_to_any.rs b/src/tools/clippy/clippy_lints/src/coerce_container_to_any.rs
new file mode 100644
index 00000000000..2b659253763
--- /dev/null
+++ b/src/tools/clippy/clippy_lints/src/coerce_container_to_any.rs
@@ -0,0 +1,108 @@
+use clippy_utils::diagnostics::span_lint_and_sugg;
+use clippy_utils::source::snippet;
+use clippy_utils::sym;
+use rustc_errors::Applicability;
+use rustc_hir::{Expr, ExprKind};
+use rustc_lint::{LateContext, LateLintPass};
+use rustc_middle::ty::{self, ExistentialPredicate, Ty, TyCtxt};
+use rustc_session::declare_lint_pass;
+
+declare_clippy_lint! {
+    /// ### What it does
+    ///
+    /// Protects against unintended coercion of references to container types to `&dyn Any` when the
+    /// container type dereferences to a `dyn Any` which could be directly referenced instead.
+    ///
+    /// ### Why is this bad?
+    ///
+    /// The intention is usually to get a reference to the `dyn Any` the value dereferences to,
+    /// rather than coercing a reference to the container itself to `&dyn Any`.
+    ///
+    /// ### Example
+    ///
+    /// Because `Box<dyn Any>` itself implements `Any`, `&Box<dyn Any>`
+    /// can be coerced to an `&dyn Any` which refers to *the `Box` itself*, rather than the
+    /// inner `dyn Any`.
+    /// ```no_run
+    /// # use std::any::Any;
+    /// let x: Box<dyn Any> = Box::new(0u32);
+    /// let dyn_any_of_box: &dyn Any = &x;
+    ///
+    /// // Fails as we have a &dyn Any to the Box, not the u32
+    /// assert_eq!(dyn_any_of_box.downcast_ref::<u32>(), None);
+    /// ```
+    /// Use instead:
+    /// ```no_run
+    /// # use std::any::Any;
+    /// let x: Box<dyn Any> = Box::new(0u32);
+    /// let dyn_any_of_u32: &dyn Any = &*x;
+    ///
+    /// // Succeeds since we have a &dyn Any to the inner u32!
+    /// assert_eq!(dyn_any_of_u32.downcast_ref::<u32>(), Some(&0u32));
+    /// ```
+    #[clippy::version = "1.88.0"]
+    pub COERCE_CONTAINER_TO_ANY,
+    nursery,
+    "coercing to `&dyn Any` when dereferencing could produce a `dyn Any` without coercion is usually not intended"
+}
+declare_lint_pass!(CoerceContainerToAny => [COERCE_CONTAINER_TO_ANY]);
+
+impl<'tcx> LateLintPass<'tcx> for CoerceContainerToAny {
+    fn check_expr(&mut self, cx: &LateContext<'tcx>, e: &'tcx Expr<'_>) {
+        // If this expression has an effective type of `&dyn Any` ...
+        {
+            let coerced_ty = cx.typeck_results().expr_ty_adjusted(e);
+
+            let ty::Ref(_, coerced_ref_ty, _) = *coerced_ty.kind() else {
+                return;
+            };
+            if !is_dyn_any(cx.tcx, coerced_ref_ty) {
+                return;
+            }
+        }
+
+        let expr_ty = cx.typeck_results().expr_ty(e);
+        let ty::Ref(_, expr_ref_ty, _) = *expr_ty.kind() else {
+            return;
+        };
+        // ... but only due to coercion ...
+        if is_dyn_any(cx.tcx, expr_ref_ty) {
+            return;
+        }
+        // ... and it also *derefs* to `dyn Any` ...
+        let Some((depth, target)) = clippy_utils::ty::deref_chain(cx, expr_ref_ty).enumerate().last() else {
+            return;
+        };
+        if !is_dyn_any(cx.tcx, target) {
+            return;
+        }
+
+        // ... that's probably not intended.
+        let (span, deref_count) = match e.kind {
+            // If `e` was already an `&` expression, skip `*&` in the suggestion
+            ExprKind::AddrOf(_, _, referent) => (referent.span, depth),
+            _ => (e.span, depth + 1),
+        };
+        span_lint_and_sugg(
+            cx,
+            COERCE_CONTAINER_TO_ANY,
+            e.span,
+            format!("coercing `{expr_ty}` to `&dyn Any`"),
+            "consider dereferencing",
+            format!("&{}{}", str::repeat("*", deref_count), snippet(cx, span, "x")),
+            Applicability::MaybeIncorrect,
+        );
+    }
+}
+
+fn is_dyn_any(tcx: TyCtxt<'_>, ty: Ty<'_>) -> bool {
+    let ty::Dynamic(traits, ..) = ty.kind() else {
+        return false;
+    };
+    traits.iter().any(|binder| {
+        let ExistentialPredicate::Trait(t) = binder.skip_binder() else {
+            return false;
+        };
+        tcx.is_diagnostic_item(sym::Any, t.def_id)
+    })
+}
diff --git a/src/tools/clippy/clippy_lints/src/copies.rs b/src/tools/clippy/clippy_lints/src/copies.rs
index 2467fc95fd0..5ef726638a5 100644
--- a/src/tools/clippy/clippy_lints/src/copies.rs
+++ b/src/tools/clippy/clippy_lints/src/copies.rs
@@ -425,7 +425,9 @@ fn scan_block_for_eq<'tcx>(
             modifies_any_local(cx, stmt, &cond_locals)
                 || !eq_stmts(stmt, blocks, |b| b.stmts.get(i), &mut eq, &mut moved_locals)
         })
-        .map_or(block.stmts.len(), |(i, _)| i);
+        .map_or(block.stmts.len(), |(i, stmt)| {
+            adjust_by_closest_callsite(i, stmt, block.stmts[..i].iter().enumerate().rev())
+        });
 
     if local_needs_ordered_drop {
         return BlockEq {
@@ -467,7 +469,9 @@ fn scan_block_for_eq<'tcx>(
                     .is_none_or(|s| hash != hash_stmt(cx, s))
             })
         })
-        .map_or(block.stmts.len() - start_end_eq, |(i, _)| i);
+        .map_or(block.stmts.len() - start_end_eq, |(i, stmt)| {
+            adjust_by_closest_callsite(i, stmt, (0..i).rev().zip(block.stmts[(block.stmts.len() - i)..].iter()))
+        });
 
     let moved_locals_at_start = moved_locals.len();
     let mut i = end_search_start;
@@ -522,6 +526,49 @@ fn scan_block_for_eq<'tcx>(
     }
 }
 
+/// Adjusts the index for which the statements begin to differ to the closest macro callsite. This
+/// avoids giving suggestions that requires splitting a macro call in half, when only a part of the
+/// macro expansion is equal.
+///
+/// For example, for the following macro:
+/// ```rust,ignore
+/// macro_rules! foo {
+///    ($x:expr) => {
+///        let y = 42;
+///        $x;
+///    };
+/// }
+/// ```
+/// If the macro is called like this:
+/// ```rust,ignore
+/// if false {
+///    let z = 42;
+///    foo!(println!("Hello"));
+/// } else {
+///    let z = 42;
+///    foo!(println!("World"));
+/// }
+/// ```
+/// Although the expanded `let y = 42;` is equal, the macro call should not be included in the
+/// suggestion.
+fn adjust_by_closest_callsite<'tcx>(
+    i: usize,
+    stmt: &'tcx Stmt<'tcx>,
+    mut iter: impl Iterator<Item = (usize, &'tcx Stmt<'tcx>)>,
+) -> usize {
+    let Some((_, first)) = iter.next() else {
+        return 0;
+    };
+
+    // If it is already at the boundary of a macro call, then just return.
+    if first.span.source_callsite() != stmt.span.source_callsite() {
+        return i;
+    }
+
+    iter.find(|(_, stmt)| stmt.span.source_callsite() != first.span.source_callsite())
+        .map_or(0, |(i, _)| i + 1)
+}
+
 fn check_for_warn_of_moved_symbol(cx: &LateContext<'_>, symbols: &[(HirId, Symbol)], if_expr: &Expr<'_>) -> bool {
     get_enclosing_block(cx, if_expr.hir_id).is_some_and(|block| {
         let ignore_span = block.span.shrink_to_lo().to(if_expr.span);
diff --git a/src/tools/clippy/clippy_lints/src/create_dir.rs b/src/tools/clippy/clippy_lints/src/create_dir.rs
index b43906903a0..695b25aeb0b 100644
--- a/src/tools/clippy/clippy_lints/src/create_dir.rs
+++ b/src/tools/clippy/clippy_lints/src/create_dir.rs
@@ -1,7 +1,6 @@
 use clippy_utils::diagnostics::span_lint_and_then;
-use clippy_utils::source::snippet_with_applicability;
 use rustc_errors::Applicability;
-use rustc_hir::{Expr, ExprKind};
+use rustc_hir::{Expr, ExprKind, QPath};
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_session::declare_lint_pass;
 use rustc_span::sym;
@@ -34,10 +33,12 @@ declare_lint_pass!(CreateDir => [CREATE_DIR]);
 
 impl LateLintPass<'_> for CreateDir {
     fn check_expr(&mut self, cx: &LateContext<'_>, expr: &Expr<'_>) {
-        if let ExprKind::Call(func, [arg]) = expr.kind
+        if let ExprKind::Call(func, [_]) = expr.kind
             && let ExprKind::Path(ref path) = func.kind
             && let Some(def_id) = cx.qpath_res(path, func.hir_id).opt_def_id()
             && cx.tcx.is_diagnostic_item(sym::fs_create_dir, def_id)
+            && let QPath::Resolved(_, path) = path
+            && let Some(last) = path.segments.last()
         {
             span_lint_and_then(
                 cx,
@@ -45,15 +46,15 @@ impl LateLintPass<'_> for CreateDir {
                 expr.span,
                 "calling `std::fs::create_dir` where there may be a better way",
                 |diag| {
-                    let mut app = Applicability::MaybeIncorrect;
-                    diag.span_suggestion_verbose(
-                        expr.span,
+                    let mut suggestions = vec![(last.ident.span.shrink_to_hi(), "_all".to_owned())];
+                    if path.segments.len() == 1 {
+                        suggestions.push((path.span.shrink_to_lo(), "std::fs::".to_owned()));
+                    }
+
+                    diag.multipart_suggestion_verbose(
                         "consider calling `std::fs::create_dir_all` instead",
-                        format!(
-                            "create_dir_all({})",
-                            snippet_with_applicability(cx, arg.span, "..", &mut app)
-                        ),
-                        app,
+                        suggestions,
+                        Applicability::MaybeIncorrect,
                     );
                 },
             );
diff --git a/src/tools/clippy/clippy_lints/src/ctfe.rs b/src/tools/clippy/clippy_lints/src/ctfe.rs
deleted file mode 100644
index 7bae04a10f1..00000000000
--- a/src/tools/clippy/clippy_lints/src/ctfe.rs
+++ /dev/null
@@ -1,26 +0,0 @@
-use rustc_hir::def_id::LocalDefId;
-use rustc_hir::intravisit::FnKind;
-use rustc_hir::{Body, FnDecl};
-use rustc_lint::{LateContext, LateLintPass};
-use rustc_session::declare_lint_pass;
-use rustc_span::Span;
-
-declare_lint_pass! {
-    /// Ensures that Constant-time Function Evaluation is being done (specifically, MIR lint passes).
-    /// As Clippy deactivates codegen, this lint ensures that CTFE (used in hard errors) is still ran.
-    ClippyCtfe => []
-}
-
-impl<'tcx> LateLintPass<'tcx> for ClippyCtfe {
-    fn check_fn(
-        &mut self,
-        cx: &LateContext<'_>,
-        _: FnKind<'tcx>,
-        _: &'tcx FnDecl<'tcx>,
-        _: &'tcx Body<'tcx>,
-        _: Span,
-        defid: LocalDefId,
-    ) {
-        cx.tcx.ensure_ok().mir_drops_elaborated_and_const_checked(defid); // Lint
-    }
-}
diff --git a/src/tools/clippy/clippy_lints/src/declared_lints.rs b/src/tools/clippy/clippy_lints/src/declared_lints.rs
index 5fcb851dfeb..1e3907d9ede 100644
--- a/src/tools/clippy/clippy_lints/src/declared_lints.rs
+++ b/src/tools/clippy/clippy_lints/src/declared_lints.rs
@@ -77,6 +77,7 @@ pub static LINTS: &[&crate::LintInfo] = &[
     crate::cfg_not_test::CFG_NOT_TEST_INFO,
     crate::checked_conversions::CHECKED_CONVERSIONS_INFO,
     crate::cloned_ref_to_slice_refs::CLONED_REF_TO_SLICE_REFS_INFO,
+    crate::coerce_container_to_any::COERCE_CONTAINER_TO_ANY_INFO,
     crate::cognitive_complexity::COGNITIVE_COMPLEXITY_INFO,
     crate::collapsible_if::COLLAPSIBLE_ELSE_IF_INFO,
     crate::collapsible_if::COLLAPSIBLE_IF_INFO,
@@ -119,6 +120,7 @@ pub static LINTS: &[&crate::LintInfo] = &[
     crate::doc::DOC_MARKDOWN_INFO,
     crate::doc::DOC_NESTED_REFDEFS_INFO,
     crate::doc::DOC_OVERINDENTED_LIST_ITEMS_INFO,
+    crate::doc::DOC_SUSPICIOUS_FOOTNOTES_INFO,
     crate::doc::EMPTY_DOCS_INFO,
     crate::doc::MISSING_ERRORS_DOC_INFO,
     crate::doc::MISSING_PANICS_DOC_INFO,
@@ -166,6 +168,7 @@ pub static LINTS: &[&crate::LintInfo] = &[
     crate::floating_point_arithmetic::SUBOPTIMAL_FLOPS_INFO,
     crate::format::USELESS_FORMAT_INFO,
     crate::format_args::FORMAT_IN_FORMAT_ARGS_INFO,
+    crate::format_args::POINTER_FORMAT_INFO,
     crate::format_args::TO_STRING_IN_FORMAT_ARGS_INFO,
     crate::format_args::UNINLINED_FORMAT_ARGS_INFO,
     crate::format_args::UNNECESSARY_DEBUG_FORMATTING_INFO,
@@ -211,6 +214,7 @@ pub static LINTS: &[&crate::LintInfo] = &[
     crate::indexing_slicing::INDEXING_SLICING_INFO,
     crate::indexing_slicing::OUT_OF_BOUNDS_INDEXING_INFO,
     crate::ineffective_open_options::INEFFECTIVE_OPEN_OPTIONS_INFO,
+    crate::infallible_try_from::INFALLIBLE_TRY_FROM_INFO,
     crate::infinite_iter::INFINITE_ITER_INFO,
     crate::infinite_iter::MAYBE_INFINITE_ITER_INFO,
     crate::inherent_impl::MULTIPLE_INHERENT_IMPL_INFO,
@@ -379,6 +383,7 @@ pub static LINTS: &[&crate::LintInfo] = &[
     crate::methods::INSPECT_FOR_EACH_INFO,
     crate::methods::INTO_ITER_ON_REF_INFO,
     crate::methods::IO_OTHER_ERROR_INFO,
+    crate::methods::IP_CONSTANT_INFO,
     crate::methods::IS_DIGIT_ASCII_RADIX_INFO,
     crate::methods::ITERATOR_STEP_BY_ZERO_INFO,
     crate::methods::ITER_CLONED_COLLECT_INFO,
diff --git a/src/tools/clippy/clippy_lints/src/default.rs b/src/tools/clippy/clippy_lints/src/default.rs
index 886c325b355..a48e4d2fbd5 100644
--- a/src/tools/clippy/clippy_lints/src/default.rs
+++ b/src/tools/clippy/clippy_lints/src/default.rs
@@ -1,10 +1,9 @@
 use clippy_utils::diagnostics::{span_lint_and_note, span_lint_and_sugg};
 use clippy_utils::source::snippet_with_context;
 use clippy_utils::ty::{has_drop, is_copy};
-use clippy_utils::{contains_name, get_parent_expr, in_automatically_derived, is_from_proc_macro};
+use clippy_utils::{contains_name, get_parent_expr, in_automatically_derived, is_expr_default, is_from_proc_macro};
 use rustc_data_structures::fx::FxHashSet;
 use rustc_errors::Applicability;
-use rustc_hir::def::Res;
 use rustc_hir::{Block, Expr, ExprKind, PatKind, QPath, Stmt, StmtKind, StructTailExpr};
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_middle::ty;
@@ -129,7 +128,7 @@ impl<'tcx> LateLintPass<'tcx> for Default {
                 // only take bindings to identifiers
                 && let PatKind::Binding(_, binding_id, ident, _) = local.pat.kind
                 // only when assigning `... = Default::default()`
-                && is_expr_default(expr, cx)
+                && is_expr_default(cx, expr)
                 && let binding_type = cx.typeck_results().node_type(binding_id)
                 && let ty::Adt(adt, args) = *binding_type.kind()
                 && adt.is_struct()
@@ -251,19 +250,6 @@ impl<'tcx> LateLintPass<'tcx> for Default {
     }
 }
 
-/// Checks if the given expression is the `default` method belonging to the `Default` trait.
-fn is_expr_default<'tcx>(expr: &'tcx Expr<'tcx>, cx: &LateContext<'tcx>) -> bool {
-    if let ExprKind::Call(fn_expr, []) = &expr.kind
-        && let ExprKind::Path(qpath) = &fn_expr.kind
-        && let Res::Def(_, def_id) = cx.qpath_res(qpath, fn_expr.hir_id)
-    {
-        // right hand side of assignment is `Default::default`
-        cx.tcx.is_diagnostic_item(sym::default_fn, def_id)
-    } else {
-        false
-    }
-}
-
 /// Returns the reassigned field and the assigning expression (right-hand side of assign).
 fn field_reassigned_by_stmt<'tcx>(this: &Stmt<'tcx>, binding_name: Symbol) -> Option<(Ident, &'tcx Expr<'tcx>)> {
     if let StmtKind::Semi(later_expr) = this.kind
diff --git a/src/tools/clippy/clippy_lints/src/dereference.rs b/src/tools/clippy/clippy_lints/src/dereference.rs
index cde9528cd87..7463d7b5c3b 100644
--- a/src/tools/clippy/clippy_lints/src/dereference.rs
+++ b/src/tools/clippy/clippy_lints/src/dereference.rs
@@ -972,7 +972,7 @@ fn report<'tcx>(
                 "&"
             };
 
-            let expr_str = if !expr_is_macro_call && is_ufcs && expr.precedence() < ExprPrecedence::Prefix {
+            let expr_str = if !expr_is_macro_call && is_ufcs && cx.precedence(expr) < ExprPrecedence::Prefix {
                 Cow::Owned(format!("({expr_str})"))
             } else {
                 expr_str
@@ -1015,10 +1015,10 @@ fn report<'tcx>(
                         Node::Expr(e) => match e.kind {
                             ExprKind::Call(callee, _) if callee.hir_id != data.first_expr.hir_id => false,
                             ExprKind::Call(..) => {
-                                expr.precedence() < ExprPrecedence::Unambiguous
+                                cx.precedence(expr) < ExprPrecedence::Unambiguous
                                     || matches!(expr.kind, ExprKind::Field(..))
                             },
-                            _ => expr.precedence() < e.precedence(),
+                            _ => cx.precedence(expr) < cx.precedence(e),
                         },
                         _ => false,
                     };
@@ -1066,7 +1066,7 @@ fn report<'tcx>(
                         Mutability::Not => "&",
                         Mutability::Mut => "&mut ",
                     };
-                    (prefix, expr.precedence() < ExprPrecedence::Prefix)
+                    (prefix, cx.precedence(expr) < ExprPrecedence::Prefix)
                 },
                 None if !ty.is_ref() && data.adjusted_ty.is_ref() => ("&", false),
                 _ => ("", false),
@@ -1172,7 +1172,7 @@ impl<'tcx> Dereferencing<'tcx> {
                 },
                 Some(parent) if !parent.span.from_expansion() => {
                     // Double reference might be needed at this point.
-                    if parent.precedence() == ExprPrecedence::Unambiguous {
+                    if cx.precedence(parent) == ExprPrecedence::Unambiguous {
                         // Parentheses would be needed here, don't lint.
                         *outer_pat = None;
                     } else {
diff --git a/src/tools/clippy/clippy_lints/src/disallowed_names.rs b/src/tools/clippy/clippy_lints/src/disallowed_names.rs
index f55b0cf1c50..566aa12b08f 100644
--- a/src/tools/clippy/clippy_lints/src/disallowed_names.rs
+++ b/src/tools/clippy/clippy_lints/src/disallowed_names.rs
@@ -1,6 +1,6 @@
 use clippy_config::Conf;
 use clippy_utils::diagnostics::span_lint;
-use clippy_utils::is_in_test;
+use clippy_utils::{is_from_proc_macro, is_in_test};
 use rustc_data_structures::fx::FxHashSet;
 use rustc_hir::{Pat, PatKind};
 use rustc_lint::{LateContext, LateLintPass};
@@ -43,8 +43,10 @@ impl_lint_pass!(DisallowedNames => [DISALLOWED_NAMES]);
 impl<'tcx> LateLintPass<'tcx> for DisallowedNames {
     fn check_pat(&mut self, cx: &LateContext<'tcx>, pat: &'tcx Pat<'_>) {
         if let PatKind::Binding(.., ident, _) = pat.kind
+            && !ident.span.from_expansion()
             && self.disallow.contains(&ident.name)
             && !is_in_test(cx.tcx, pat.hir_id)
+            && !is_from_proc_macro(cx, &ident)
         {
             span_lint(
                 cx,
diff --git a/src/tools/clippy/clippy_lints/src/disallowed_types.rs b/src/tools/clippy/clippy_lints/src/disallowed_types.rs
index 821bb25d2ce..7875cdd77e8 100644
--- a/src/tools/clippy/clippy_lints/src/disallowed_types.rs
+++ b/src/tools/clippy/clippy_lints/src/disallowed_types.rs
@@ -105,10 +105,10 @@ impl_lint_pass!(DisallowedTypes => [DISALLOWED_TYPES]);
 
 impl<'tcx> LateLintPass<'tcx> for DisallowedTypes {
     fn check_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx Item<'tcx>) {
-        if let ItemKind::Use(path, UseKind::Single(_)) = &item.kind {
-            if let Some(res) = path.res.type_ns {
-                self.check_res_emit(cx, &res, item.span);
-            }
+        if let ItemKind::Use(path, UseKind::Single(_)) = &item.kind
+            && let Some(res) = path.res.type_ns
+        {
+            self.check_res_emit(cx, &res, item.span);
         }
     }
 
diff --git a/src/tools/clippy/clippy_lints/src/doc/doc_suspicious_footnotes.rs b/src/tools/clippy/clippy_lints/src/doc/doc_suspicious_footnotes.rs
new file mode 100644
index 00000000000..289b6b915d4
--- /dev/null
+++ b/src/tools/clippy/clippy_lints/src/doc/doc_suspicious_footnotes.rs
@@ -0,0 +1,113 @@
+use clippy_utils::diagnostics::span_lint_and_then;
+use rustc_ast::token::CommentKind;
+use rustc_errors::Applicability;
+use rustc_hir::{AttrStyle, Attribute};
+use rustc_lint::{LateContext, LintContext};
+use rustc_resolve::rustdoc::DocFragmentKind;
+
+use std::ops::Range;
+
+use super::{DOC_SUSPICIOUS_FOOTNOTES, Fragments};
+
+pub fn check(cx: &LateContext<'_>, doc: &str, range: Range<usize>, fragments: &Fragments<'_>, attrs: &[Attribute]) {
+    for i in doc[range.clone()]
+        .bytes()
+        .enumerate()
+        .filter_map(|(i, c)| if c == b'[' { Some(i) } else { None })
+    {
+        let start = i + range.start;
+        if doc.as_bytes().get(start + 1) == Some(&b'^')
+            && let Some(end) = all_numbers_upto_brace(doc, start + 2)
+            && doc.as_bytes().get(end) != Some(&b':')
+            && doc.as_bytes().get(start - 1) != Some(&b'\\')
+            && let Some(this_fragment) = {
+                // the `doc` string contains all fragments concatenated together
+                // figure out which one this suspicious footnote comes from
+                let mut starting_position = 0;
+                let mut found_fragment = fragments.fragments.last();
+                for fragment in fragments.fragments {
+                    if start >= starting_position && start < starting_position + fragment.doc.as_str().len() {
+                        found_fragment = Some(fragment);
+                        break;
+                    }
+                    starting_position += fragment.doc.as_str().len();
+                }
+                found_fragment
+            }
+        {
+            let span = fragments.span(cx, start..end).unwrap_or(this_fragment.span);
+            span_lint_and_then(
+                cx,
+                DOC_SUSPICIOUS_FOOTNOTES,
+                span,
+                "looks like a footnote ref, but has no matching footnote",
+                |diag| {
+                    if this_fragment.kind == DocFragmentKind::SugaredDoc {
+                        let (doc_attr, (_, doc_attr_comment_kind)) = attrs
+                            .iter()
+                            .filter(|attr| attr.span().overlaps(this_fragment.span))
+                            .rev()
+                            .find_map(|attr| Some((attr, attr.doc_str_and_comment_kind()?)))
+                            .unwrap();
+                        let (to_add, terminator) = match (doc_attr_comment_kind, doc_attr.style()) {
+                            (CommentKind::Line, AttrStyle::Outer) => ("\n///\n/// ", ""),
+                            (CommentKind::Line, AttrStyle::Inner) => ("\n//!\n//! ", ""),
+                            (CommentKind::Block, AttrStyle::Outer) => ("\n/** ", " */"),
+                            (CommentKind::Block, AttrStyle::Inner) => ("\n/*! ", " */"),
+                        };
+                        diag.span_suggestion_verbose(
+                            doc_attr.span().shrink_to_hi(),
+                            "add footnote definition",
+                            format!(
+                                "{to_add}{label}: <!-- description -->{terminator}",
+                                label = &doc[start..end]
+                            ),
+                            Applicability::HasPlaceholders,
+                        );
+                    } else {
+                        let is_file_include = cx
+                            .sess()
+                            .source_map()
+                            .span_to_snippet(this_fragment.span)
+                            .as_ref()
+                            .map(|vdoc| vdoc.trim())
+                            == Ok(doc);
+                        if is_file_include {
+                            // if this is a file include, then there's no quote marks
+                            diag.span_suggestion_verbose(
+                                this_fragment.span.shrink_to_hi(),
+                                "add footnote definition",
+                                format!("\n\n{label}: <!-- description -->", label = &doc[start..end],),
+                                Applicability::HasPlaceholders,
+                            );
+                        } else {
+                            // otherwise, we wrap in a string
+                            diag.span_suggestion_verbose(
+                                this_fragment.span,
+                                "add footnote definition",
+                                format!(
+                                    "r#\"{doc}\n\n{label}: <!-- description -->\"#",
+                                    doc = this_fragment.doc,
+                                    label = &doc[start..end],
+                                ),
+                                Applicability::HasPlaceholders,
+                            );
+                        }
+                    }
+                },
+            );
+        }
+    }
+}
+
+fn all_numbers_upto_brace(text: &str, i: usize) -> Option<usize> {
+    for (j, c) in text.as_bytes()[i..].iter().copied().enumerate().take(64) {
+        if c == b']' && j != 0 {
+            return Some(i + j + 1);
+        }
+        if !c.is_ascii_digit() || j >= 64 {
+            break;
+        }
+    }
+    None
+}
diff --git a/src/tools/clippy/clippy_lints/src/doc/mod.rs b/src/tools/clippy/clippy_lints/src/doc/mod.rs
index c46dd09d60c..e0fc2fd9347 100644
--- a/src/tools/clippy/clippy_lints/src/doc/mod.rs
+++ b/src/tools/clippy/clippy_lints/src/doc/mod.rs
@@ -25,6 +25,7 @@ use std::ops::Range;
 use url::Url;
 
 mod doc_comment_double_space_linebreaks;
+mod doc_suspicious_footnotes;
 mod include_in_doc_without_cfg;
 mod lazy_continuation;
 mod link_with_quotes;
@@ -607,6 +608,37 @@ declare_clippy_lint! {
     "double-space used for doc comment linebreak instead of `\\`"
 }
 
+declare_clippy_lint! {
+    /// ### What it does
+    /// Detects syntax that looks like a footnote reference.
+    ///
+    /// Rustdoc footnotes are compatible with GitHub-Flavored Markdown (GFM).
+    /// GFM does not parse a footnote reference unless its definition also
+    /// exists. This lint checks for footnote references with missing
+    /// definitions, unless it thinks you're writing a regex.
+    ///
+    /// ### Why is this bad?
+    /// This probably means that a footnote was meant to exist,
+    /// but was not written.
+    ///
+    /// ### Example
+    /// ```no_run
+    /// /// This is not a footnote[^1], because no definition exists.
+    /// fn my_fn() {}
+    /// ```
+    /// Use instead:
+    /// ```no_run
+    /// /// This is a footnote[^1].
+    /// ///
+    /// /// [^1]: defined here
+    /// fn my_fn() {}
+    /// ```
+    #[clippy::version = "1.88.0"]
+    pub DOC_SUSPICIOUS_FOOTNOTES,
+    suspicious,
+    "looks like a link or footnote ref, but with no definition"
+}
+
 pub struct Documentation {
     valid_idents: FxHashSet<String>,
     check_private_items: bool,
@@ -638,7 +670,8 @@ impl_lint_pass!(Documentation => [
     DOC_OVERINDENTED_LIST_ITEMS,
     TOO_LONG_FIRST_DOC_PARAGRAPH,
     DOC_INCLUDE_WITHOUT_CFG,
-    DOC_COMMENT_DOUBLE_SPACE_LINEBREAKS
+    DOC_COMMENT_DOUBLE_SPACE_LINEBREAKS,
+    DOC_SUSPICIOUS_FOOTNOTES,
 ]);
 
 impl EarlyLintPass for Documentation {
@@ -825,6 +858,7 @@ fn check_attrs(cx: &LateContext<'_>, valid_idents: &FxHashSet<String>, attrs: &[
             doc: &doc,
             fragments: &fragments,
         },
+        attrs,
     ))
 }
 
@@ -905,6 +939,7 @@ fn check_doc<'a, Events: Iterator<Item = (pulldown_cmark::Event<'a>, Range<usize
     events: Events,
     doc: &str,
     fragments: Fragments<'_>,
+    attrs: &[Attribute],
 ) -> DocHeaders {
     // true if a safety header was found
     let mut headers = DocHeaders::default();
@@ -1148,7 +1183,8 @@ fn check_doc<'a, Events: Iterator<Item = (pulldown_cmark::Event<'a>, Range<usize
                         // Don't check the text associated with external URLs
                         continue;
                     }
-                    text_to_check.push((text, range, code_level));
+                    text_to_check.push((text, range.clone(), code_level));
+                    doc_suspicious_footnotes::check(cx, doc, range, &fragments, attrs);
                 }
             }
             FootnoteReference(_) => {}
diff --git a/src/tools/clippy/clippy_lints/src/endian_bytes.rs b/src/tools/clippy/clippy_lints/src/endian_bytes.rs
index a7670ffce88..75db923b1c3 100644
--- a/src/tools/clippy/clippy_lints/src/endian_bytes.rs
+++ b/src/tools/clippy/clippy_lints/src/endian_bytes.rs
@@ -1,6 +1,6 @@
 use crate::Lint;
 use clippy_utils::diagnostics::span_lint_and_then;
-use clippy_utils::is_lint_allowed;
+use clippy_utils::{is_lint_allowed, sym};
 use rustc_hir::{Expr, ExprKind};
 use rustc_lint::{LateContext, LateLintPass, LintContext};
 use rustc_middle::ty::Ty;
@@ -65,9 +65,9 @@ declare_clippy_lint! {
 
 declare_lint_pass!(EndianBytes => [HOST_ENDIAN_BYTES, LITTLE_ENDIAN_BYTES, BIG_ENDIAN_BYTES]);
 
-const HOST_NAMES: [&str; 2] = ["from_ne_bytes", "to_ne_bytes"];
-const LITTLE_NAMES: [&str; 2] = ["from_le_bytes", "to_le_bytes"];
-const BIG_NAMES: [&str; 2] = ["from_be_bytes", "to_be_bytes"];
+const HOST_NAMES: [Symbol; 2] = [sym::from_ne_bytes, sym::to_ne_bytes];
+const LITTLE_NAMES: [Symbol; 2] = [sym::from_le_bytes, sym::to_le_bytes];
+const BIG_NAMES: [Symbol; 2] = [sym::from_be_bytes, sym::to_be_bytes];
 
 #[derive(Clone, Debug)]
 enum LintKind {
@@ -95,7 +95,7 @@ impl LintKind {
         }
     }
 
-    fn as_name(&self, prefix: Prefix) -> &str {
+    fn as_name(&self, prefix: Prefix) -> Symbol {
         let index = usize::from(prefix == Prefix::To);
 
         match self {
@@ -133,7 +133,7 @@ fn maybe_lint_endian_bytes(cx: &LateContext<'_>, expr: &Expr<'_>, prefix: Prefix
     let le = LintKind::Little.as_name(prefix);
     let be = LintKind::Big.as_name(prefix);
 
-    let (lint, other_lints) = match name.as_str() {
+    let (lint, other_lints) = match name {
         name if name == ne => ((&LintKind::Host), [(&LintKind::Little), (&LintKind::Big)]),
         name if name == le => ((&LintKind::Little), [(&LintKind::Host), (&LintKind::Big)]),
         name if name == be => ((&LintKind::Big), [(&LintKind::Host), (&LintKind::Little)]),
diff --git a/src/tools/clippy/clippy_lints/src/format_args.rs b/src/tools/clippy/clippy_lints/src/format_args.rs
index a26e736c7ae..0c39aae9ca9 100644
--- a/src/tools/clippy/clippy_lints/src/format_args.rs
+++ b/src/tools/clippy/clippy_lints/src/format_args.rs
@@ -1,6 +1,8 @@
+use std::collections::hash_map::Entry;
+
 use arrayvec::ArrayVec;
 use clippy_config::Conf;
-use clippy_utils::diagnostics::{span_lint_and_sugg, span_lint_and_then};
+use clippy_utils::diagnostics::{span_lint, span_lint_and_sugg, span_lint_and_then};
 use clippy_utils::macros::{
     FormatArgsStorage, FormatParamUsage, MacroCall, find_format_arg_expr, format_arg_removal_span,
     format_placeholder_format_span, is_assert_macro, is_format_macro, is_panic, matching_root_macro_call,
@@ -9,7 +11,7 @@ use clippy_utils::macros::{
 use clippy_utils::msrvs::{self, Msrv};
 use clippy_utils::source::{SpanRangeExt, snippet};
 use clippy_utils::ty::{implements_trait, is_type_lang_item};
-use clippy_utils::{is_diag_trait_item, is_from_proc_macro, is_in_test};
+use clippy_utils::{is_diag_trait_item, is_from_proc_macro, is_in_test, trait_ref_of_method};
 use itertools::Itertools;
 use rustc_ast::{
     FormatArgPosition, FormatArgPositionKind, FormatArgsPiece, FormatArgumentKind, FormatCount, FormatOptions,
@@ -22,10 +24,12 @@ use rustc_errors::SuggestionStyle::{CompletelyHidden, ShowCode};
 use rustc_hir::{Expr, ExprKind, LangItem};
 use rustc_lint::{LateContext, LateLintPass, LintContext};
 use rustc_middle::ty::adjustment::{Adjust, Adjustment};
-use rustc_middle::ty::{List, Ty, TyCtxt};
+use rustc_middle::ty::{self, GenericArg, List, TraitRef, Ty, TyCtxt, Upcast};
 use rustc_session::impl_lint_pass;
 use rustc_span::edition::Edition::Edition2021;
 use rustc_span::{Span, Symbol, sym};
+use rustc_trait_selection::infer::TyCtxtInferExt;
+use rustc_trait_selection::traits::{Obligation, ObligationCause, Selection, SelectionContext};
 
 declare_clippy_lint! {
     /// ### What it does
@@ -194,12 +198,41 @@ declare_clippy_lint! {
     "use of a format specifier that has no effect"
 }
 
+declare_clippy_lint! {
+    /// ### What it does
+    /// Detects [pointer format] as well as `Debug` formatting of raw pointers or function pointers
+    /// or any types that have a derived `Debug` impl that recursively contains them.
+    ///
+    /// ### Why restrict this?
+    /// The addresses are only useful in very specific contexts, and certain projects may want to keep addresses of
+    /// certain data structures or functions from prying hacker eyes as an additional line of security.
+    ///
+    /// ### Known problems
+    /// The lint currently only looks through derived `Debug` implementations. Checking whether a manual
+    /// implementation prints an address is left as an exercise to the next lint implementer.
+    ///
+    /// ### Example
+    /// ```no_run
+    /// let foo = &0_u32;
+    /// fn bar() {}
+    /// println!("{:p}", foo);
+    /// let _ = format!("{:?}", &(bar as fn()));
+    /// ```
+    ///
+    /// [pointer format]: https://doc.rust-lang.org/std/fmt/index.html#formatting-traits
+    #[clippy::version = "1.88.0"]
+    pub POINTER_FORMAT,
+    restriction,
+    "formatting a pointer"
+}
+
 impl_lint_pass!(FormatArgs<'_> => [
     FORMAT_IN_FORMAT_ARGS,
     TO_STRING_IN_FORMAT_ARGS,
     UNINLINED_FORMAT_ARGS,
     UNNECESSARY_DEBUG_FORMATTING,
     UNUSED_FORMAT_SPECS,
+    POINTER_FORMAT,
 ]);
 
 #[allow(clippy::struct_field_names)]
@@ -208,6 +241,8 @@ pub struct FormatArgs<'tcx> {
     msrv: Msrv,
     ignore_mixed: bool,
     ty_msrv_map: FxHashMap<Ty<'tcx>, Option<RustcVersion>>,
+    has_derived_debug: FxHashMap<Ty<'tcx>, bool>,
+    has_pointer_format: FxHashMap<Ty<'tcx>, bool>,
 }
 
 impl<'tcx> FormatArgs<'tcx> {
@@ -218,6 +253,8 @@ impl<'tcx> FormatArgs<'tcx> {
             msrv: conf.msrv,
             ignore_mixed: conf.allow_mixed_uninlined_format_args,
             ty_msrv_map,
+            has_derived_debug: FxHashMap::default(),
+            has_pointer_format: FxHashMap::default(),
         }
     }
 }
@@ -228,7 +265,7 @@ impl<'tcx> LateLintPass<'tcx> for FormatArgs<'tcx> {
             && is_format_macro(cx, macro_call.def_id)
             && let Some(format_args) = self.format_args.get(cx, expr, macro_call.expn)
         {
-            let linter = FormatArgsExpr {
+            let mut linter = FormatArgsExpr {
                 cx,
                 expr,
                 macro_call: &macro_call,
@@ -236,6 +273,8 @@ impl<'tcx> LateLintPass<'tcx> for FormatArgs<'tcx> {
                 ignore_mixed: self.ignore_mixed,
                 msrv: &self.msrv,
                 ty_msrv_map: &self.ty_msrv_map,
+                has_derived_debug: &mut self.has_derived_debug,
+                has_pointer_format: &mut self.has_pointer_format,
             };
 
             linter.check_templates();
@@ -255,10 +294,12 @@ struct FormatArgsExpr<'a, 'tcx> {
     ignore_mixed: bool,
     msrv: &'a Msrv,
     ty_msrv_map: &'a FxHashMap<Ty<'tcx>, Option<RustcVersion>>,
+    has_derived_debug: &'a mut FxHashMap<Ty<'tcx>, bool>,
+    has_pointer_format: &'a mut FxHashMap<Ty<'tcx>, bool>,
 }
 
 impl<'tcx> FormatArgsExpr<'_, 'tcx> {
-    fn check_templates(&self) {
+    fn check_templates(&mut self) {
         for piece in &self.format_args.template {
             if let FormatArgsPiece::Placeholder(placeholder) = piece
                 && let Ok(index) = placeholder.argument.index
@@ -279,6 +320,17 @@ impl<'tcx> FormatArgsExpr<'_, 'tcx> {
                 if placeholder.format_trait == FormatTrait::Debug {
                     let name = self.cx.tcx.item_name(self.macro_call.def_id);
                     self.check_unnecessary_debug_formatting(name, arg_expr);
+                    if let Some(span) = placeholder.span
+                        && self.has_pointer_debug(self.cx.typeck_results().expr_ty(arg_expr), 0)
+                    {
+                        span_lint(self.cx, POINTER_FORMAT, span, "pointer formatting detected");
+                    }
+                }
+
+                if placeholder.format_trait == FormatTrait::Pointer
+                    && let Some(span) = placeholder.span
+                {
+                    span_lint(self.cx, POINTER_FORMAT, span, "pointer formatting detected");
                 }
             }
         }
@@ -490,6 +542,16 @@ impl<'tcx> FormatArgsExpr<'_, 'tcx> {
             && let ty = cx.typeck_results().expr_ty(value)
             && self.can_display_format(ty)
         {
+            // If the parent function is a method of `Debug`, we don't want to lint
+            // because it is likely that the user wants to use `Debug` formatting.
+            let parent_fn = cx.tcx.hir_get_parent_item(value.hir_id);
+            if let Some(trait_ref) = trait_ref_of_method(cx, parent_fn)
+                && let Some(trait_def_id) = trait_ref.trait_def_id()
+                && cx.tcx.is_diagnostic_item(sym::Debug, trait_def_id)
+            {
+                return;
+            }
+
             let snippet = snippet(cx.sess(), value.span, "..");
             span_lint_and_then(
                 cx,
@@ -559,6 +621,58 @@ impl<'tcx> FormatArgsExpr<'_, 'tcx> {
 
         false
     }
+
+    fn has_pointer_debug(&mut self, ty: Ty<'tcx>, depth: usize) -> bool {
+        let cx = self.cx;
+        let tcx = cx.tcx;
+        if !tcx.recursion_limit().value_within_limit(depth) {
+            return false;
+        }
+        let depth = depth + 1;
+        let typing_env = cx.typing_env();
+        let ty = tcx.normalize_erasing_regions(typing_env, ty);
+        match ty.kind() {
+            ty::RawPtr(..) | ty::FnPtr(..) | ty::FnDef(..) => true,
+            ty::Ref(_, t, _) | ty::Slice(t) | ty::Array(t, _) => self.has_pointer_debug(*t, depth),
+            ty::Tuple(ts) => ts.iter().any(|t| self.has_pointer_debug(t, depth)),
+            ty::Adt(adt, args) => {
+                match self.has_pointer_format.entry(ty) {
+                    Entry::Occupied(o) => return *o.get(),
+                    Entry::Vacant(v) => v.insert(false),
+                };
+                let derived_debug = if let Some(&known) = self.has_derived_debug.get(&ty) {
+                    known
+                } else {
+                    let Some(trait_id) = tcx.get_diagnostic_item(sym::Debug) else {
+                        return false;
+                    };
+                    let (infcx, param_env) = tcx.infer_ctxt().build_with_typing_env(typing_env);
+                    let trait_ref = TraitRef::new(tcx, trait_id, [GenericArg::from(ty)]);
+                    let obligation = Obligation {
+                        cause: ObligationCause::dummy(),
+                        param_env,
+                        recursion_depth: 0,
+                        predicate: trait_ref.upcast(tcx),
+                    };
+                    let selection = SelectionContext::new(&infcx).select(&obligation);
+                    let derived = if let Ok(Some(Selection::UserDefined(data))) = selection {
+                        tcx.has_attr(data.impl_def_id, sym::automatically_derived)
+                    } else {
+                        false
+                    };
+                    self.has_derived_debug.insert(ty, derived);
+                    derived
+                };
+                let pointer_debug = derived_debug
+                    && adt.all_fields().any(|f| {
+                        self.has_pointer_debug(tcx.normalize_erasing_regions(typing_env, f.ty(tcx, args)), depth)
+                    });
+                self.has_pointer_format.insert(ty, pointer_debug);
+                pointer_debug
+            },
+            _ => false,
+        }
+    }
 }
 
 fn make_ty_msrv_map(tcx: TyCtxt<'_>) -> FxHashMap<Ty<'_>, Option<RustcVersion>> {
diff --git a/src/tools/clippy/clippy_lints/src/functions/mod.rs b/src/tools/clippy/clippy_lints/src/functions/mod.rs
index d0d02a382d1..6051dc9479b 100644
--- a/src/tools/clippy/clippy_lints/src/functions/mod.rs
+++ b/src/tools/clippy/clippy_lints/src/functions/mod.rs
@@ -303,7 +303,7 @@ declare_clippy_lint! {
     /// to the name of the method, when there is a field's whose name matches that of the method.
     ///
     /// ### Why is this bad?
-    /// It is most likely that such a  method is a bug caused by a typo or by copy-pasting.
+    /// It is most likely that such a method is a bug caused by a typo or by copy-pasting.
     ///
     /// ### Example
 
diff --git a/src/tools/clippy/clippy_lints/src/if_let_mutex.rs b/src/tools/clippy/clippy_lints/src/if_let_mutex.rs
index 6444e99ae9c..a99118f90f8 100644
--- a/src/tools/clippy/clippy_lints/src/if_let_mutex.rs
+++ b/src/tools/clippy/clippy_lints/src/if_let_mutex.rs
@@ -1,14 +1,13 @@
 use clippy_utils::diagnostics::span_lint_and_then;
 use clippy_utils::ty::is_type_diagnostic_item;
 use clippy_utils::visitors::for_each_expr_without_closures;
-use clippy_utils::{eq_expr_value, higher};
+use clippy_utils::{eq_expr_value, higher, sym};
 use core::ops::ControlFlow;
 use rustc_errors::Diag;
 use rustc_hir::{Expr, ExprKind};
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_session::declare_lint_pass;
 use rustc_span::edition::Edition::Edition2024;
-use rustc_span::sym;
 
 declare_clippy_lint! {
     /// ### What it does
@@ -94,7 +93,7 @@ fn mutex_lock_call<'tcx>(
     op_mutex: Option<&'tcx Expr<'_>>,
 ) -> ControlFlow<&'tcx Expr<'tcx>> {
     if let ExprKind::MethodCall(path, self_arg, [], _) = &expr.kind
-        && path.ident.as_str() == "lock"
+        && path.ident.name == sym::lock
         && let ty = cx.typeck_results().expr_ty(self_arg).peel_refs()
         && is_type_diagnostic_item(cx, ty, sym::Mutex)
         && op_mutex.is_none_or(|op| eq_expr_value(cx, self_arg, op))
diff --git a/src/tools/clippy/clippy_lints/src/implicit_saturating_sub.rs b/src/tools/clippy/clippy_lints/src/implicit_saturating_sub.rs
index 0823ef53ef9..c743501da25 100644
--- a/src/tools/clippy/clippy_lints/src/implicit_saturating_sub.rs
+++ b/src/tools/clippy/clippy_lints/src/implicit_saturating_sub.rs
@@ -3,7 +3,7 @@ use clippy_utils::diagnostics::{span_lint_and_sugg, span_lint_and_then};
 use clippy_utils::msrvs::{self, Msrv};
 use clippy_utils::sugg::{Sugg, make_binop};
 use clippy_utils::{
-    SpanlessEq, eq_expr_value, higher, is_in_const_context, is_integer_literal, peel_blocks, peel_blocks_with_stmt,
+    SpanlessEq, eq_expr_value, higher, is_in_const_context, is_integer_literal, peel_blocks, peel_blocks_with_stmt, sym,
 };
 use rustc_ast::ast::LitKind;
 use rustc_data_structures::packed::Pu128;
@@ -11,7 +11,7 @@ use rustc_errors::Applicability;
 use rustc_hir::{AssignOpKind, BinOp, BinOpKind, Expr, ExprKind, QPath};
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_session::impl_lint_pass;
-use rustc_span::Span;
+use rustc_span::{Span, Symbol};
 
 declare_clippy_lint! {
     /// ### What it does
@@ -325,7 +325,7 @@ fn check_with_condition<'tcx>(
         }
 
         // Get the variable name
-        let var_name = ares_path.segments[0].ident.name.as_str();
+        let var_name = ares_path.segments[0].ident.name;
         match cond_num_val.kind {
             ExprKind::Lit(cond_lit) => {
                 // Check if the constant is zero
@@ -337,7 +337,7 @@ fn check_with_condition<'tcx>(
                 }
             },
             ExprKind::Path(QPath::TypeRelative(_, name)) => {
-                if name.ident.as_str() == "MIN"
+                if name.ident.name == sym::MIN
                     && let Some(const_id) = cx.typeck_results().type_dependent_def_id(cond_num_val.hir_id)
                     && let Some(impl_id) = cx.tcx.impl_of_method(const_id)
                     && let None = cx.tcx.impl_trait_ref(impl_id) // An inherent impl
@@ -348,7 +348,7 @@ fn check_with_condition<'tcx>(
             },
             ExprKind::Call(func, []) => {
                 if let ExprKind::Path(QPath::TypeRelative(_, name)) = func.kind
-                    && name.ident.as_str() == "min_value"
+                    && name.ident.name == sym::min_value
                     && let Some(func_id) = cx.typeck_results().type_dependent_def_id(func.hir_id)
                     && let Some(impl_id) = cx.tcx.impl_of_method(func_id)
                     && let None = cx.tcx.impl_trait_ref(impl_id) // An inherent impl
@@ -383,7 +383,7 @@ fn subtracts_one<'a>(cx: &LateContext<'_>, expr: &'a Expr<'a>) -> Option<&'a Exp
     }
 }
 
-fn print_lint_and_sugg(cx: &LateContext<'_>, var_name: &str, expr: &Expr<'_>) {
+fn print_lint_and_sugg(cx: &LateContext<'_>, var_name: Symbol, expr: &Expr<'_>) {
     span_lint_and_sugg(
         cx,
         IMPLICIT_SATURATING_SUB,
diff --git a/src/tools/clippy/clippy_lints/src/infallible_try_from.rs b/src/tools/clippy/clippy_lints/src/infallible_try_from.rs
new file mode 100644
index 00000000000..b54c289fa7e
--- /dev/null
+++ b/src/tools/clippy/clippy_lints/src/infallible_try_from.rs
@@ -0,0 +1,76 @@
+use clippy_utils::diagnostics::span_lint;
+use clippy_utils::sym;
+use rustc_errors::MultiSpan;
+use rustc_hir::{AssocItemKind, Item, ItemKind};
+use rustc_lint::{LateContext, LateLintPass};
+use rustc_session::declare_lint_pass;
+
+declare_clippy_lint! {
+    /// ### What it does
+    ///
+    /// Finds manual impls of `TryFrom` with infallible error types.
+    ///
+    /// ### Why is this bad?
+    ///
+    /// Infalliable conversions should be implemented via `From` with the blanket conversion.
+    ///
+    /// ### Example
+    /// ```no_run
+    /// use std::convert::Infallible;
+    /// struct MyStruct(i16);
+    /// impl TryFrom<i16> for MyStruct {
+    ///     type Error = Infallible;
+    ///     fn try_from(other: i16) -> Result<Self, Infallible> {
+    ///         Ok(Self(other.into()))
+    ///     }
+    /// }
+    /// ```
+    /// Use instead:
+    /// ```no_run
+    /// struct MyStruct(i16);
+    /// impl From<i16> for MyStruct {
+    ///     fn from(other: i16) -> Self {
+    ///         Self(other)
+    ///     }
+    /// }
+    /// ```
+    #[clippy::version = "1.88.0"]
+    pub INFALLIBLE_TRY_FROM,
+    suspicious,
+    "TryFrom with infallible Error type"
+}
+declare_lint_pass!(InfallibleTryFrom => [INFALLIBLE_TRY_FROM]);
+
+impl<'tcx> LateLintPass<'tcx> for InfallibleTryFrom {
+    fn check_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx Item<'tcx>) {
+        let ItemKind::Impl(imp) = item.kind else { return };
+        let Some(r#trait) = imp.of_trait else { return };
+        let Some(trait_def_id) = r#trait.trait_def_id() else {
+            return;
+        };
+        if !cx.tcx.is_diagnostic_item(sym::TryFrom, trait_def_id) {
+            return;
+        }
+        for ii in imp.items {
+            if ii.kind == AssocItemKind::Type {
+                let ii = cx.tcx.hir_impl_item(ii.id);
+                if ii.ident.name != sym::Error {
+                    continue;
+                }
+                let ii_ty = ii.expect_type();
+                let ii_ty_span = ii_ty.span;
+                let ii_ty = clippy_utils::ty::ty_from_hir_ty(cx, ii_ty);
+                if !ii_ty.is_inhabited_from(cx.tcx, ii.owner_id.to_def_id(), cx.typing_env()) {
+                    let mut span = MultiSpan::from_span(cx.tcx.def_span(item.owner_id.to_def_id()));
+                    span.push_span_label(ii_ty_span, "infallible error type");
+                    span_lint(
+                        cx,
+                        INFALLIBLE_TRY_FROM,
+                        span,
+                        "infallible TryFrom impl; consider implementing From, instead",
+                    );
+                }
+            }
+        }
+    }
+}
diff --git a/src/tools/clippy/clippy_lints/src/lib.rs b/src/tools/clippy/clippy_lints/src/lib.rs
index 92eb3d7a7c5..be9142b17fe 100644
--- a/src/tools/clippy/clippy_lints/src/lib.rs
+++ b/src/tools/clippy/clippy_lints/src/lib.rs
@@ -55,6 +55,7 @@ extern crate rustc_session;
 extern crate rustc_span;
 extern crate rustc_target;
 extern crate rustc_trait_selection;
+extern crate smallvec;
 extern crate thin_vec;
 
 #[macro_use]
@@ -65,11 +66,10 @@ extern crate clippy_utils;
 
 mod utils;
 
-pub mod ctfe; // Very important lint, do not remove (rust#125116)
 pub mod declared_lints;
 pub mod deprecated_lints;
 
-// begin lints modules, do not remove this comment, it’s used in `update_lints`
+// begin lints modules, do not remove this comment, it's used in `update_lints`
 mod absolute_paths;
 mod almost_complete_range;
 mod approx_const;
@@ -95,6 +95,7 @@ mod casts;
 mod cfg_not_test;
 mod checked_conversions;
 mod cloned_ref_to_slice_refs;
+mod coerce_container_to_any;
 mod cognitive_complexity;
 mod collapsible_if;
 mod collection_is_never_read;
@@ -169,6 +170,7 @@ mod inconsistent_struct_constructor;
 mod index_refutable_slice;
 mod indexing_slicing;
 mod ineffective_open_options;
+mod infallible_try_from;
 mod infinite_iter;
 mod inherent_impl;
 mod inherent_to_string;
@@ -404,7 +406,7 @@ mod zero_div_zero;
 mod zero_repeat_side_effects;
 mod zero_sized_map_values;
 mod zombie_processes;
-// end lints modules, do not remove this comment, it’s used in `update_lints`
+// end lints modules, do not remove this comment, it's used in `update_lints`
 
 use clippy_config::{Conf, get_configuration_metadata, sanitize_explanation};
 use clippy_utils::macros::FormatArgsStorage;
@@ -583,8 +585,6 @@ pub fn register_lints(store: &mut rustc_lint::LintStore, conf: &'static Conf) {
     let attrs = attr_storage.clone();
     store.register_early_pass(move || Box::new(AttrCollector::new(attrs.clone())));
 
-    store.register_late_pass(|_| Box::new(ctfe::ClippyCtfe));
-
     store.register_late_pass(move |_| Box::new(operators::arithmetic_side_effects::ArithmeticSideEffects::new(conf)));
     store.register_late_pass(|_| Box::new(utils::dump_hir::DumpHir));
     store.register_late_pass(|_| Box::new(utils::author::Author));
@@ -946,5 +946,7 @@ pub fn register_lints(store: &mut rustc_lint::LintStore, conf: &'static Conf) {
     store.register_late_pass(|_| Box::new(single_option_map::SingleOptionMap));
     store.register_late_pass(move |_| Box::new(redundant_test_prefix::RedundantTestPrefix));
     store.register_late_pass(|_| Box::new(cloned_ref_to_slice_refs::ClonedRefToSliceRefs::new(conf)));
+    store.register_late_pass(|_| Box::new(infallible_try_from::InfallibleTryFrom));
+    store.register_late_pass(|_| Box::new(coerce_container_to_any::CoerceContainerToAny));
     // add lints here, do not remove this comment, it's used in `new_lint`
 }
diff --git a/src/tools/clippy/clippy_lints/src/loops/manual_flatten.rs b/src/tools/clippy/clippy_lints/src/loops/manual_flatten.rs
index 81f14b7b2b0..ddb8bb536c0 100644
--- a/src/tools/clippy/clippy_lints/src/loops/manual_flatten.rs
+++ b/src/tools/clippy/clippy_lints/src/loops/manual_flatten.rs
@@ -2,8 +2,9 @@ use super::MANUAL_FLATTEN;
 use super::utils::make_iterator_snippet;
 use clippy_utils::diagnostics::span_lint_and_then;
 use clippy_utils::msrvs::{self, Msrv};
+use clippy_utils::source::{HasSession, indent_of, reindent_multiline, snippet_with_applicability};
 use clippy_utils::visitors::is_local_used;
-use clippy_utils::{higher, is_refutable, path_to_local_id, peel_blocks_with_stmt};
+use clippy_utils::{higher, is_refutable, path_to_local_id, peel_blocks_with_stmt, span_contains_comment};
 use rustc_errors::Applicability;
 use rustc_hir::def::{DefKind, Res};
 use rustc_hir::{Expr, Pat, PatKind};
@@ -39,13 +40,20 @@ pub(super) fn check<'tcx>(
         && msrv.meets(cx, msrvs::ITER_FLATTEN)
         && !is_refutable(cx, inner_pat)
     {
+        if arg.span.from_expansion() || if_then.span.from_expansion() {
+            return;
+        }
         let if_let_type = if some_ctor { "Some" } else { "Ok" };
         // Prepare the error message
         let msg =
             format!("unnecessary `if let` since only the `{if_let_type}` variant of the iterator element is used");
 
         // Prepare the help message
-        let mut applicability = Applicability::MaybeIncorrect;
+        let mut applicability = if span_contains_comment(cx.sess().source_map(), body.span) {
+            Applicability::MaybeIncorrect
+        } else {
+            Applicability::MachineApplicable
+        };
         let arg_snippet = make_iterator_snippet(cx, arg, &mut applicability);
         let copied = match cx.typeck_results().expr_ty(let_expr).kind() {
             ty::Ref(_, inner, _) => match inner.kind() {
@@ -55,20 +63,26 @@ pub(super) fn check<'tcx>(
             _ => "",
         };
 
-        let sugg = format!("{arg_snippet}{copied}.flatten()");
+        let help_msg = "try `.flatten()` and remove the `if let` statement in the for loop";
 
-        // If suggestion is not a one-liner, it won't be shown inline within the error message. In that
-        // case, it will be shown in the extra `help` message at the end, which is why the first
-        // `help_msg` needs to refer to the correct relative position of the suggestion.
-        let help_msg = if sugg.contains('\n') {
-            "remove the `if let` statement in the for loop and then..."
-        } else {
-            "...and remove the `if let` statement in the for loop"
-        };
+        let pat_snippet =
+            snippet_with_applicability(cx, inner_pat.span.source_callsite(), "_", &mut applicability).to_string();
+        let body_snippet =
+            snippet_with_applicability(cx, if_then.span.source_callsite(), "[body]", &mut applicability).to_string();
+        let suggestions = vec![
+            // flatten the iterator
+            (arg.span, format!("{arg_snippet}{copied}.flatten()")),
+            (pat.span, pat_snippet),
+            // remove the `if let` statement
+            (
+                body.span,
+                reindent_multiline(&body_snippet, true, indent_of(cx, body.span)),
+            ),
+        ];
 
         span_lint_and_then(cx, MANUAL_FLATTEN, span, msg, |diag| {
-            diag.span_suggestion(arg.span, "try", sugg, applicability);
             diag.span_help(inner_expr.span, help_msg);
+            diag.multipart_suggestion("try", suggestions, applicability);
         });
     }
 }
diff --git a/src/tools/clippy/clippy_lints/src/loops/single_element_loop.rs b/src/tools/clippy/clippy_lints/src/loops/single_element_loop.rs
index 12719c4f94b..d66771a8b5b 100644
--- a/src/tools/clippy/clippy_lints/src/loops/single_element_loop.rs
+++ b/src/tools/clippy/clippy_lints/src/loops/single_element_loop.rs
@@ -84,7 +84,7 @@ pub(super) fn check<'tcx>(
         if !prefix.is_empty()
             && (
                 // Precedence of internal expression is less than or equal to precedence of `&expr`.
-                arg_expression.precedence() <= ExprPrecedence::Prefix || is_range_literal(arg_expression)
+                cx.precedence(arg_expression) <= ExprPrecedence::Prefix || is_range_literal(arg_expression)
             )
         {
             arg_snip = format!("({arg_snip})").into();
diff --git a/src/tools/clippy/clippy_lints/src/manual_clamp.rs b/src/tools/clippy/clippy_lints/src/manual_clamp.rs
index 02afe9f0997..42fe386d2c3 100644
--- a/src/tools/clippy/clippy_lints/src/manual_clamp.rs
+++ b/src/tools/clippy/clippy_lints/src/manual_clamp.rs
@@ -8,7 +8,7 @@ use clippy_utils::ty::implements_trait;
 use clippy_utils::visitors::is_const_evaluatable;
 use clippy_utils::{
     MaybePath, eq_expr_value, is_diag_trait_item, is_in_const_context, is_trait_method, path_res, path_to_local_id,
-    peel_blocks, peel_blocks_with_stmt,
+    peel_blocks, peel_blocks_with_stmt, sym,
 };
 use itertools::Itertools;
 use rustc_errors::{Applicability, Diag};
@@ -18,7 +18,6 @@ use rustc_lint::{LateContext, LateLintPass};
 use rustc_middle::ty::Ty;
 use rustc_session::impl_lint_pass;
 use rustc_span::Span;
-use rustc_span::symbol::sym;
 use std::cmp::Ordering;
 use std::ops::Deref;
 
@@ -299,9 +298,9 @@ fn is_max_min_pattern<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'tcx>) -> O
         && (cx.typeck_results().expr_ty_adjusted(input).is_floating_point() || is_trait_method(cx, receiver, sym::Ord))
     {
         let is_float = cx.typeck_results().expr_ty_adjusted(input).is_floating_point();
-        let (min, max) = match (seg_first.ident.as_str(), seg_second.ident.as_str()) {
-            ("min", "max") => (arg_second, arg_first),
-            ("max", "min") => (arg_first, arg_second),
+        let (min, max) = match (seg_first.ident.name, seg_second.ident.name) {
+            (sym::min, sym::max) => (arg_second, arg_first),
+            (sym::max, sym::min) => (arg_first, arg_second),
             _ => return None,
         };
         Some(ClampSuggestion {
diff --git a/src/tools/clippy/clippy_lints/src/manual_string_new.rs b/src/tools/clippy/clippy_lints/src/manual_string_new.rs
index 73ee1c3c78a..9b590e092d0 100644
--- a/src/tools/clippy/clippy_lints/src/manual_string_new.rs
+++ b/src/tools/clippy/clippy_lints/src/manual_string_new.rs
@@ -1,11 +1,12 @@
 use clippy_utils::diagnostics::span_lint_and_sugg;
+use clippy_utils::sym;
 use rustc_ast::LitKind;
 use rustc_errors::Applicability::MachineApplicable;
 use rustc_hir::{Expr, ExprKind, PathSegment, QPath, TyKind};
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_middle::ty;
 use rustc_session::declare_lint_pass;
-use rustc_span::{Span, sym};
+use rustc_span::Span;
 
 declare_clippy_lint! {
     /// ### What it does
@@ -89,9 +90,10 @@ fn warn_then_suggest(cx: &LateContext<'_>, span: Span) {
 
 /// Tries to parse an expression as a method call, emitting the warning if necessary.
 fn parse_method_call(cx: &LateContext<'_>, span: Span, path_segment: &PathSegment<'_>, receiver: &Expr<'_>) {
-    let ident = path_segment.ident.as_str();
     let method_arg_kind = &receiver.kind;
-    if ["to_string", "to_owned", "into"].contains(&ident) && is_expr_kind_empty_str(method_arg_kind) {
+    if matches!(path_segment.ident.name, sym::to_string | sym::to_owned | sym::into)
+        && is_expr_kind_empty_str(method_arg_kind)
+    {
         warn_then_suggest(cx, span);
     } else if let ExprKind::Call(func, [arg]) = method_arg_kind {
         // If our first argument is a function call itself, it could be an `unwrap`-like function.
diff --git a/src/tools/clippy/clippy_lints/src/match_result_ok.rs b/src/tools/clippy/clippy_lints/src/match_result_ok.rs
index 2a5fc8b6609..e0cb5d14d3c 100644
--- a/src/tools/clippy/clippy_lints/src/match_result_ok.rs
+++ b/src/tools/clippy/clippy_lints/src/match_result_ok.rs
@@ -1,12 +1,11 @@
 use clippy_utils::diagnostics::span_lint_and_sugg;
 use clippy_utils::source::snippet_with_context;
 use clippy_utils::ty::is_type_diagnostic_item;
-use clippy_utils::{higher, is_res_lang_ctor};
+use clippy_utils::{higher, is_res_lang_ctor, sym};
 use rustc_errors::Applicability;
 use rustc_hir::{Expr, ExprKind, LangItem, PatKind};
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_session::declare_lint_pass;
-use rustc_span::sym;
 
 declare_clippy_lint! {
     /// ### What it does
@@ -57,7 +56,7 @@ impl<'tcx> LateLintPass<'tcx> for MatchResultOk {
 
         if let ExprKind::MethodCall(ok_path, recv, [], ..) = let_expr.kind //check is expr.ok() has type Result<T,E>.ok(, _)
             && let PatKind::TupleStruct(ref pat_path, [ok_pat], _)  = let_pat.kind //get operation
-            && ok_path.ident.as_str() == "ok"
+            && ok_path.ident.name == sym::ok
             && is_type_diagnostic_item(cx, cx.typeck_results().expr_ty(recv), sym::Result)
             && is_res_lang_ctor(cx, cx.qpath_res(pat_path, let_pat.hir_id), LangItem::OptionSome)
             && let ctxt = expr.span.ctxt()
diff --git a/src/tools/clippy/clippy_lints/src/matches/manual_utils.rs b/src/tools/clippy/clippy_lints/src/matches/manual_utils.rs
index d0905733ab5..dbae71bbb1b 100644
--- a/src/tools/clippy/clippy_lints/src/matches/manual_utils.rs
+++ b/src/tools/clippy/clippy_lints/src/matches/manual_utils.rs
@@ -117,7 +117,7 @@ where
     // it's being passed by value.
     let scrutinee = peel_hir_expr_refs(scrutinee).0;
     let (scrutinee_str, _) = snippet_with_context(cx, scrutinee.span, expr_ctxt, "..", &mut app);
-    let scrutinee_str = if scrutinee.span.eq_ctxt(expr.span) && scrutinee.precedence() < ExprPrecedence::Unambiguous {
+    let scrutinee_str = if scrutinee.span.eq_ctxt(expr.span) && cx.precedence(scrutinee) < ExprPrecedence::Unambiguous {
         format!("({scrutinee_str})")
     } else {
         scrutinee_str.into()
diff --git a/src/tools/clippy/clippy_lints/src/matches/match_single_binding.rs b/src/tools/clippy/clippy_lints/src/matches/match_single_binding.rs
index adda3586990..6a76c6cedd0 100644
--- a/src/tools/clippy/clippy_lints/src/matches/match_single_binding.rs
+++ b/src/tools/clippy/clippy_lints/src/matches/match_single_binding.rs
@@ -1,7 +1,7 @@
 use clippy_utils::diagnostics::span_lint_and_sugg;
 use clippy_utils::macros::HirNode;
 use clippy_utils::source::{indent_of, snippet, snippet_block_with_context, snippet_with_context};
-use clippy_utils::{get_parent_expr, is_refutable, peel_blocks};
+use clippy_utils::{is_refutable, peel_blocks};
 use rustc_errors::Applicability;
 use rustc_hir::{Arm, Expr, ExprKind, Node, PatKind, StmtKind};
 use rustc_lint::LateContext;
@@ -9,6 +9,7 @@ use rustc_span::Span;
 
 use super::MATCH_SINGLE_BINDING;
 
+#[derive(Debug)]
 enum AssignmentExpr {
     Assign { span: Span, match_span: Span },
     Local { span: Span, pat_span: Span },
@@ -160,6 +161,17 @@ fn opt_parent_assign_span<'a>(cx: &LateContext<'a>, ex: &Expr<'a>) -> Option<Ass
     None
 }
 
+fn expr_parent_requires_curlies<'a>(cx: &LateContext<'a>, match_expr: &Expr<'a>) -> bool {
+    let parent = cx.tcx.parent_hir_node(match_expr.hir_id);
+    matches!(
+        parent,
+        Node::Expr(Expr {
+            kind: ExprKind::Closure { .. },
+            ..
+        }) | Node::AnonConst(..)
+    )
+}
+
 fn sugg_with_curlies<'a>(
     cx: &LateContext<'a>,
     (ex, match_expr): (&Expr<'a>, &Expr<'a>),
@@ -172,9 +184,7 @@ fn sugg_with_curlies<'a>(
     let mut indent = " ".repeat(indent_of(cx, ex.span).unwrap_or(0));
 
     let (mut cbrace_start, mut cbrace_end) = (String::new(), String::new());
-    if let Some(parent_expr) = get_parent_expr(cx, match_expr)
-        && let ExprKind::Closure { .. } = parent_expr.kind
-    {
+    if expr_parent_requires_curlies(cx, match_expr) {
         cbrace_end = format!("\n{indent}}}");
         // Fix body indent due to the closure
         indent = " ".repeat(indent_of(cx, bind_names).unwrap_or(0));
diff --git a/src/tools/clippy/clippy_lints/src/matches/match_str_case_mismatch.rs b/src/tools/clippy/clippy_lints/src/matches/match_str_case_mismatch.rs
index 65b93a095b9..8b4c1700051 100644
--- a/src/tools/clippy/clippy_lints/src/matches/match_str_case_mismatch.rs
+++ b/src/tools/clippy/clippy_lints/src/matches/match_str_case_mismatch.rs
@@ -1,6 +1,7 @@
 use std::ops::ControlFlow;
 
 use clippy_utils::diagnostics::span_lint_and_sugg;
+use clippy_utils::sym;
 use clippy_utils::ty::is_type_lang_item;
 use rustc_ast::ast::LitKind;
 use rustc_errors::Applicability;
@@ -42,7 +43,7 @@ impl<'tcx> Visitor<'tcx> for MatchExprVisitor<'_, 'tcx> {
     type Result = ControlFlow<CaseMethod>;
     fn visit_expr(&mut self, ex: &'tcx Expr<'_>) -> Self::Result {
         if let ExprKind::MethodCall(segment, receiver, [], _) = ex.kind {
-            let result = self.case_altered(segment.ident.as_str(), receiver);
+            let result = self.case_altered(segment.ident.name, receiver);
             if result.is_break() {
                 return result;
             }
@@ -53,7 +54,7 @@ impl<'tcx> Visitor<'tcx> for MatchExprVisitor<'_, 'tcx> {
 }
 
 impl MatchExprVisitor<'_, '_> {
-    fn case_altered(&mut self, segment_ident: &str, receiver: &Expr<'_>) -> ControlFlow<CaseMethod> {
+    fn case_altered(&mut self, segment_ident: Symbol, receiver: &Expr<'_>) -> ControlFlow<CaseMethod> {
         if let Some(case_method) = get_case_method(segment_ident) {
             let ty = self.cx.typeck_results().expr_ty(receiver).peel_refs();
 
@@ -66,12 +67,12 @@ impl MatchExprVisitor<'_, '_> {
     }
 }
 
-fn get_case_method(segment_ident_str: &str) -> Option<CaseMethod> {
-    match segment_ident_str {
-        "to_lowercase" => Some(CaseMethod::LowerCase),
-        "to_ascii_lowercase" => Some(CaseMethod::AsciiLowerCase),
-        "to_uppercase" => Some(CaseMethod::UpperCase),
-        "to_ascii_uppercase" => Some(CaseMethod::AsciiUppercase),
+fn get_case_method(segment_ident: Symbol) -> Option<CaseMethod> {
+    match segment_ident {
+        sym::to_lowercase => Some(CaseMethod::LowerCase),
+        sym::to_ascii_lowercase => Some(CaseMethod::AsciiLowerCase),
+        sym::to_uppercase => Some(CaseMethod::UpperCase),
+        sym::to_ascii_uppercase => Some(CaseMethod::AsciiUppercase),
         _ => None,
     }
 }
diff --git a/src/tools/clippy/clippy_lints/src/methods/ip_constant.rs b/src/tools/clippy/clippy_lints/src/methods/ip_constant.rs
new file mode 100644
index 00000000000..83803fba6a1
--- /dev/null
+++ b/src/tools/clippy/clippy_lints/src/methods/ip_constant.rs
@@ -0,0 +1,52 @@
+use clippy_utils::consts::{ConstEvalCtxt, Constant};
+use clippy_utils::diagnostics::span_lint_and_then;
+use rustc_errors::Applicability;
+use rustc_hir::{Expr, ExprKind, QPath, Ty, TyKind};
+use rustc_lint::LateContext;
+use rustc_span::sym;
+use smallvec::SmallVec;
+
+use super::IP_CONSTANT;
+
+pub(super) fn check(cx: &LateContext<'_>, expr: &Expr<'_>, func: &Expr<'_>, args: &[Expr<'_>]) {
+    if let ExprKind::Path(QPath::TypeRelative(
+        Ty {
+            kind: TyKind::Path(QPath::Resolved(_, func_path)),
+            ..
+        },
+        p,
+    )) = func.kind
+        && p.ident.name == sym::new
+        && let Some(func_def_id) = func_path.res.opt_def_id()
+        && matches!(
+            cx.tcx.get_diagnostic_name(func_def_id),
+            Some(sym::Ipv4Addr | sym::Ipv6Addr)
+        )
+        && let Some(args) = args
+            .iter()
+            .map(|arg| {
+                if let Some(Constant::Int(constant @ (0 | 1 | 127 | 255))) = ConstEvalCtxt::new(cx).eval(arg) {
+                    u8::try_from(constant).ok()
+                } else {
+                    None
+                }
+            })
+            .collect::<Option<SmallVec<[u8; 8]>>>()
+    {
+        let constant_name = match args.as_slice() {
+            [0, 0, 0, 0] | [0, 0, 0, 0, 0, 0, 0, 0] => "UNSPECIFIED",
+            [127, 0, 0, 1] | [0, 0, 0, 0, 0, 0, 0, 1] => "LOCALHOST",
+            [255, 255, 255, 255] => "BROADCAST",
+            _ => return,
+        };
+
+        span_lint_and_then(cx, IP_CONSTANT, expr.span, "hand-coded well-known IP address", |diag| {
+            diag.span_suggestion_verbose(
+                expr.span.with_lo(p.ident.span.lo()),
+                "use",
+                constant_name,
+                Applicability::MachineApplicable,
+            );
+        });
+    }
+}
diff --git a/src/tools/clippy/clippy_lints/src/methods/iter_kv_map.rs b/src/tools/clippy/clippy_lints/src/methods/iter_kv_map.rs
index c88462129af..cbb1b450e60 100644
--- a/src/tools/clippy/clippy_lints/src/methods/iter_kv_map.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/iter_kv_map.rs
@@ -46,7 +46,7 @@ pub(super) fn check<'tcx>(
 
         if let ExprKind::Path(rustc_hir::QPath::Resolved(_, path)) = body_expr.kind
             && let [local_ident] = path.segments
-            && local_ident.ident.as_str() == bound_ident.as_str()
+            && local_ident.ident.name == bound_ident.name
         {
             span_lint_and_sugg(
                 cx,
diff --git a/src/tools/clippy/clippy_lints/src/methods/manual_saturating_arithmetic.rs b/src/tools/clippy/clippy_lints/src/methods/manual_saturating_arithmetic.rs
index e2df8ce1513..c785b23bc9c 100644
--- a/src/tools/clippy/clippy_lints/src/methods/manual_saturating_arithmetic.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/manual_saturating_arithmetic.rs
@@ -72,9 +72,9 @@ fn is_min_or_max(cx: &LateContext<'_>, expr: &hir::Expr<'_>) -> Option<MinMax> {
     if let hir::ExprKind::Call(func, []) = &expr.kind
         && let hir::ExprKind::Path(hir::QPath::TypeRelative(_, segment)) = &func.kind
     {
-        match segment.ident.as_str() {
-            "max_value" => return Some(MinMax::Max),
-            "min_value" => return Some(MinMax::Min),
+        match segment.ident.name {
+            sym::max_value => return Some(MinMax::Max),
+            sym::min_value => return Some(MinMax::Min),
             _ => {},
         }
     }
diff --git a/src/tools/clippy/clippy_lints/src/methods/mod.rs b/src/tools/clippy/clippy_lints/src/methods/mod.rs
index bc159206985..347960e0003 100644
--- a/src/tools/clippy/clippy_lints/src/methods/mod.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/mod.rs
@@ -37,6 +37,7 @@ mod inefficient_to_string;
 mod inspect_for_each;
 mod into_iter_on_ref;
 mod io_other_error;
+mod ip_constant;
 mod is_digit_ascii_radix;
 mod is_empty;
 mod iter_cloned_collect;
@@ -4528,6 +4529,42 @@ declare_clippy_lint! {
     "detect swap with a temporary value"
 }
 
+declare_clippy_lint! {
+    /// ### What it does
+    /// Checks for IP addresses that could be replaced with predefined constants such as
+    /// `Ipv4Addr::new(127, 0, 0, 1)` instead of using the appropriate constants.
+    ///
+    /// ### Why is this bad?
+    /// Using specific IP addresses like `127.0.0.1` or `::1` is less clear and less maintainable than using the
+    /// predefined constants `Ipv4Addr::LOCALHOST` or `Ipv6Addr::LOCALHOST`. These constants improve code
+    /// readability, make the intent explicit, and are less error-prone.
+    ///
+    /// ### Example
+    /// ```no_run
+    /// use std::net::{Ipv4Addr, Ipv6Addr};
+    ///
+    /// // IPv4 loopback
+    /// let addr_v4 = Ipv4Addr::new(127, 0, 0, 1);
+    ///
+    /// // IPv6 loopback
+    /// let addr_v6 = Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 1);
+    /// ```
+    /// Use instead:
+    /// ```no_run
+    /// use std::net::{Ipv4Addr, Ipv6Addr};
+    ///
+    /// // IPv4 loopback
+    /// let addr_v4 = Ipv4Addr::LOCALHOST;
+    ///
+    /// // IPv6 loopback
+    /// let addr_v6 = Ipv6Addr::LOCALHOST;
+    /// ```
+    #[clippy::version = "1.89.0"]
+    pub IP_CONSTANT,
+    pedantic,
+    "hardcoded localhost IP address"
+}
+
 #[expect(clippy::struct_excessive_bools)]
 pub struct Methods {
     avoid_breaking_exported_api: bool,
@@ -4706,6 +4743,7 @@ impl_lint_pass!(Methods => [
     MANUAL_CONTAINS,
     IO_OTHER_ERROR,
     SWAP_WITH_TEMPORARY,
+    IP_CONSTANT,
 ]);
 
 /// Extracts a method call name, args, and `Span` of the method name.
@@ -4738,6 +4776,7 @@ impl<'tcx> LateLintPass<'tcx> for Methods {
                 useless_nonzero_new_unchecked::check(cx, expr, func, args, self.msrv);
                 io_other_error::check(cx, expr, func, args, self.msrv);
                 swap_with_temporary::check(cx, expr, func, args);
+                ip_constant::check(cx, expr, func, args);
             },
             ExprKind::MethodCall(method_call, receiver, args, _) => {
                 let method_span = method_call.ident.span;
diff --git a/src/tools/clippy/clippy_lints/src/methods/needless_collect.rs b/src/tools/clippy/clippy_lints/src/methods/needless_collect.rs
index 2b75d6a8248..0075bf166cc 100644
--- a/src/tools/clippy/clippy_lints/src/methods/needless_collect.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/needless_collect.rs
@@ -44,11 +44,10 @@ pub(super) fn check<'tcx>(
 
             if let ExprKind::MethodCall(name, _, args @ ([] | [_]), _) = parent.kind {
                 let mut app = Applicability::MachineApplicable;
-                let name = name.ident.as_str();
                 let collect_ty = cx.typeck_results().expr_ty(collect_expr);
 
-                let sugg: String = match name {
-                    "len" => {
+                let sugg: String = match name.ident.name {
+                    sym::len => {
                         if let Some(adt) = collect_ty.ty_adt_def()
                             && matches!(
                                 cx.tcx.get_diagnostic_name(adt.did()),
@@ -60,13 +59,13 @@ pub(super) fn check<'tcx>(
                             return;
                         }
                     },
-                    "is_empty"
+                    sym::is_empty
                         if is_is_empty_sig(cx, parent.hir_id)
                             && iterates_same_ty(cx, cx.typeck_results().expr_ty(iter_expr), collect_ty) =>
                     {
                         "next().is_none()".into()
                     },
-                    "contains" => {
+                    sym::contains => {
                         if is_contains_sig(cx, parent.hir_id, iter_expr)
                             && let Some(arg) = args.first()
                         {
diff --git a/src/tools/clippy/clippy_lints/src/methods/open_options.rs b/src/tools/clippy/clippy_lints/src/methods/open_options.rs
index bce314e64f0..fd368024177 100644
--- a/src/tools/clippy/clippy_lints/src/methods/open_options.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/open_options.rs
@@ -1,14 +1,14 @@
 use rustc_data_structures::fx::FxHashMap;
 
 use clippy_utils::diagnostics::{span_lint, span_lint_and_then};
-use clippy_utils::paths;
 use clippy_utils::ty::is_type_diagnostic_item;
+use clippy_utils::{paths, sym};
 use rustc_ast::ast::LitKind;
 use rustc_hir::{Expr, ExprKind};
 use rustc_lint::LateContext;
 use rustc_middle::ty::Ty;
+use rustc_span::Span;
 use rustc_span::source_map::Spanned;
-use rustc_span::{Span, sym};
 
 use super::{NONSENSICAL_OPEN_OPTIONS, SUSPICIOUS_OPEN_OPTIONS};
 
@@ -87,23 +87,23 @@ fn get_open_options(
                 _ => Argument::Unknown,
             };
 
-            match path.ident.as_str() {
-                "create" => {
+            match path.ident.name {
+                sym::create => {
                     options.push((OpenOption::Create, argument_option, span));
                 },
-                "create_new" => {
+                sym::create_new => {
                     options.push((OpenOption::CreateNew, argument_option, span));
                 },
-                "append" => {
+                sym::append => {
                     options.push((OpenOption::Append, argument_option, span));
                 },
-                "truncate" => {
+                sym::truncate => {
                     options.push((OpenOption::Truncate, argument_option, span));
                 },
-                "read" => {
+                sym::read => {
                     options.push((OpenOption::Read, argument_option, span));
                 },
-                "write" => {
+                sym::write => {
                     options.push((OpenOption::Write, argument_option, span));
                 },
                 _ => {
diff --git a/src/tools/clippy/clippy_lints/src/methods/str_splitn.rs b/src/tools/clippy/clippy_lints/src/methods/str_splitn.rs
index 6935ae1f391..6f78d6c6128 100644
--- a/src/tools/clippy/clippy_lints/src/methods/str_splitn.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/str_splitn.rs
@@ -285,9 +285,9 @@ fn parse_iter_usage<'tcx>(
             let did = cx.typeck_results().type_dependent_def_id(e.hir_id)?;
             let iter_id = cx.tcx.get_diagnostic_item(sym::Iterator)?;
 
-            match (name.ident.as_str(), args) {
-                ("next", []) if cx.tcx.trait_of_item(did) == Some(iter_id) => (IterUsageKind::Nth(0), e.span),
-                ("next_tuple", []) => {
+            match (name.ident.name, args) {
+                (sym::next, []) if cx.tcx.trait_of_item(did) == Some(iter_id) => (IterUsageKind::Nth(0), e.span),
+                (sym::next_tuple, []) => {
                     return if paths::ITERTOOLS_NEXT_TUPLE.matches(cx, did)
                         && let ty::Adt(adt_def, subs) = cx.typeck_results().expr_ty(e).kind()
                         && cx.tcx.is_diagnostic_item(sym::Option, adt_def.did())
@@ -303,7 +303,7 @@ fn parse_iter_usage<'tcx>(
                         None
                     };
                 },
-                ("nth" | "skip", [idx_expr]) if cx.tcx.trait_of_item(did) == Some(iter_id) => {
+                (sym::nth | sym::skip, [idx_expr]) if cx.tcx.trait_of_item(did) == Some(iter_id) => {
                     if let Some(Constant::Int(idx)) = ConstEvalCtxt::new(cx).eval(idx_expr) {
                         let span = if name.ident.as_str() == "nth" {
                             e.span
diff --git a/src/tools/clippy/clippy_lints/src/methods/unnecessary_to_owned.rs b/src/tools/clippy/clippy_lints/src/methods/unnecessary_to_owned.rs
index fdccf1fb33d..769526d131b 100644
--- a/src/tools/clippy/clippy_lints/src/methods/unnecessary_to_owned.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/unnecessary_to_owned.rs
@@ -388,9 +388,11 @@ fn check_other_call_arg<'tcx>(
         && let (input, n_refs) = peel_middle_ty_refs(*input)
         && let (trait_predicates, _) = get_input_traits_and_projections(cx, callee_def_id, input)
         && let Some(sized_def_id) = cx.tcx.lang_items().sized_trait()
+        && let Some(meta_sized_def_id) = cx.tcx.lang_items().meta_sized_trait()
         && let [trait_predicate] = trait_predicates
             .iter()
             .filter(|trait_predicate| trait_predicate.def_id() != sized_def_id)
+            .filter(|trait_predicate| trait_predicate.def_id() != meta_sized_def_id)
             .collect::<Vec<_>>()[..]
         && let Some(deref_trait_id) = cx.tcx.get_diagnostic_item(sym::Deref)
         && let Some(as_ref_trait_id) = cx.tcx.get_diagnostic_item(sym::AsRef)
diff --git a/src/tools/clippy/clippy_lints/src/multiple_bound_locations.rs b/src/tools/clippy/clippy_lints/src/multiple_bound_locations.rs
index 4b32ba83b32..741f38f9756 100644
--- a/src/tools/clippy/clippy_lints/src/multiple_bound_locations.rs
+++ b/src/tools/clippy/clippy_lints/src/multiple_bound_locations.rs
@@ -47,7 +47,7 @@ impl EarlyLintPass for MultipleBoundLocations {
 
             for param in &generics.params {
                 if !param.bounds.is_empty() {
-                    generic_params_with_bounds.insert(param.ident.name.as_str(), param.ident.span);
+                    generic_params_with_bounds.insert(param.ident.as_str(), param.ident.span);
                 }
             }
             for clause in &generics.where_clause.predicates {
@@ -64,7 +64,7 @@ impl EarlyLintPass for MultipleBoundLocations {
                     },
                     WherePredicateKind::RegionPredicate(pred) => {
                         if !pred.bounds.is_empty()
-                            && let Some(bound_span) = generic_params_with_bounds.get(&pred.lifetime.ident.name.as_str())
+                            && let Some(bound_span) = generic_params_with_bounds.get(&pred.lifetime.ident.as_str())
                         {
                             emit_lint(cx, *bound_span, pred.lifetime.ident.span);
                         }
diff --git a/src/tools/clippy/clippy_lints/src/needless_borrows_for_generic_args.rs b/src/tools/clippy/clippy_lints/src/needless_borrows_for_generic_args.rs
index 2efb55b9880..8d2f8029112 100644
--- a/src/tools/clippy/clippy_lints/src/needless_borrows_for_generic_args.rs
+++ b/src/tools/clippy/clippy_lints/src/needless_borrows_for_generic_args.rs
@@ -174,6 +174,7 @@ fn needless_borrow_count<'tcx>(
 ) -> usize {
     let destruct_trait_def_id = cx.tcx.lang_items().destruct_trait();
     let sized_trait_def_id = cx.tcx.lang_items().sized_trait();
+    let meta_sized_trait_def_id = cx.tcx.lang_items().meta_sized_trait();
     let drop_trait_def_id = cx.tcx.lang_items().drop_trait();
 
     let fn_sig = cx.tcx.fn_sig(fn_id).instantiate_identity().skip_binder();
@@ -209,6 +210,7 @@ fn needless_borrow_count<'tcx>(
         .all(|trait_def_id| {
             Some(trait_def_id) == destruct_trait_def_id
                 || Some(trait_def_id) == sized_trait_def_id
+                || Some(trait_def_id) == meta_sized_trait_def_id
                 || cx.tcx.is_diagnostic_item(sym::Any, trait_def_id)
         })
     {
diff --git a/src/tools/clippy/clippy_lints/src/needless_pass_by_value.rs b/src/tools/clippy/clippy_lints/src/needless_pass_by_value.rs
index 95623467b81..9aede1dec93 100644
--- a/src/tools/clippy/clippy_lints/src/needless_pass_by_value.rs
+++ b/src/tools/clippy/clippy_lints/src/needless_pass_by_value.rs
@@ -116,13 +116,16 @@ impl<'tcx> LateLintPass<'tcx> for NeedlessPassByValue {
         ];
 
         let sized_trait = need!(cx.tcx.lang_items().sized_trait());
+        let meta_sized_trait = need!(cx.tcx.lang_items().meta_sized_trait());
 
         let preds = traits::elaborate(cx.tcx, cx.param_env.caller_bounds().iter())
             .filter(|p| !p.is_global())
             .filter_map(|pred| {
                 // Note that we do not want to deal with qualified predicates here.
                 match pred.kind().no_bound_vars() {
-                    Some(ty::ClauseKind::Trait(pred)) if pred.def_id() != sized_trait => Some(pred),
+                    Some(ty::ClauseKind::Trait(pred))
+                        if pred.def_id() != sized_trait && pred.def_id() != meta_sized_trait
+                            => Some(pred),
                     _ => None,
                 }
             })
diff --git a/src/tools/clippy/clippy_lints/src/neg_multiply.rs b/src/tools/clippy/clippy_lints/src/neg_multiply.rs
index 74c8142787e..442280f9998 100644
--- a/src/tools/clippy/clippy_lints/src/neg_multiply.rs
+++ b/src/tools/clippy/clippy_lints/src/neg_multiply.rs
@@ -64,7 +64,7 @@ fn check_mul(cx: &LateContext<'_>, span: Span, lit: &Expr<'_>, exp: &Expr<'_>) {
     {
         let mut applicability = Applicability::MachineApplicable;
         let (snip, from_macro) = snippet_with_context(cx, exp.span, span.ctxt(), "..", &mut applicability);
-        let suggestion = if !from_macro && exp.precedence() < ExprPrecedence::Prefix && !has_enclosing_paren(&snip) {
+        let suggestion = if !from_macro && cx.precedence(exp) < ExprPrecedence::Prefix && !has_enclosing_paren(&snip) {
             format!("-({snip})")
         } else {
             format!("-{snip}")
diff --git a/src/tools/clippy/clippy_lints/src/non_canonical_impls.rs b/src/tools/clippy/clippy_lints/src/non_canonical_impls.rs
index 93865197ec9..04b09276966 100644
--- a/src/tools/clippy/clippy_lints/src/non_canonical_impls.rs
+++ b/src/tools/clippy/clippy_lints/src/non_canonical_impls.rs
@@ -293,7 +293,14 @@ fn self_cmp_call<'tcx>(
         ExprKind::Call(path, [_, _]) => path_res(cx, path)
             .opt_def_id()
             .is_some_and(|def_id| cx.tcx.is_diagnostic_item(sym::ord_cmp_method, def_id)),
-        ExprKind::MethodCall(_, _, [_other], ..) => {
+        ExprKind::MethodCall(_, recv, [_], ..) => {
+            let ExprKind::Path(path) = recv.kind else {
+                return false;
+            };
+            if last_path_segment(&path).ident.name != kw::SelfLower {
+                return false;
+            }
+
             // We can set this to true here no matter what as if it's a `MethodCall` and goes to the
             // `else` branch, it must be a method named `cmp` that isn't `Ord::cmp`
             *needs_fully_qualified = true;
diff --git a/src/tools/clippy/clippy_lints/src/pathbuf_init_then_push.rs b/src/tools/clippy/clippy_lints/src/pathbuf_init_then_push.rs
index 35caac855cf..4ce6827cac9 100644
--- a/src/tools/clippy/clippy_lints/src/pathbuf_init_then_push.rs
+++ b/src/tools/clippy/clippy_lints/src/pathbuf_init_then_push.rs
@@ -1,14 +1,14 @@
 use clippy_utils::diagnostics::span_lint_and_sugg;
-use clippy_utils::path_to_local_id;
 use clippy_utils::source::{SpanRangeExt, snippet};
 use clippy_utils::ty::is_type_diagnostic_item;
+use clippy_utils::{path_to_local_id, sym};
 use rustc_ast::{LitKind, StrStyle};
 use rustc_errors::Applicability;
 use rustc_hir::def::Res;
 use rustc_hir::{BindingMode, Block, Expr, ExprKind, HirId, LetStmt, PatKind, QPath, Stmt, StmtKind, TyKind};
 use rustc_lint::{LateContext, LateLintPass, LintContext};
 use rustc_session::impl_lint_pass;
-use rustc_span::{Span, Symbol, sym};
+use rustc_span::{Span, Symbol};
 
 declare_clippy_lint! {
     /// ### What it does
@@ -177,7 +177,7 @@ impl<'tcx> LateLintPass<'tcx> for PathbufThenPush<'tcx> {
             && let StmtKind::Expr(expr) | StmtKind::Semi(expr) = stmt.kind
             && let ExprKind::MethodCall(name, self_arg, [arg_expr], _) = expr.kind
             && path_to_local_id(self_arg, searcher.local_id)
-            && name.ident.as_str() == "push"
+            && name.ident.name == sym::push
         {
             searcher.err_span = searcher.err_span.to(stmt.span);
             searcher.arg = Some(*arg_expr);
diff --git a/src/tools/clippy/clippy_lints/src/ptr.rs b/src/tools/clippy/clippy_lints/src/ptr.rs
index 9149406642d..94cdcf00054 100644
--- a/src/tools/clippy/clippy_lints/src/ptr.rs
+++ b/src/tools/clippy/clippy_lints/src/ptr.rs
@@ -2,7 +2,7 @@ use clippy_utils::diagnostics::{span_lint_and_sugg, span_lint_and_then, span_lin
 use clippy_utils::source::SpanRangeExt;
 use clippy_utils::sugg::Sugg;
 use clippy_utils::visitors::contains_unsafe_block;
-use clippy_utils::{get_expr_use_or_unification_node, is_lint_allowed, path_def_id, path_to_local, std_or_core};
+use clippy_utils::{get_expr_use_or_unification_node, is_lint_allowed, path_def_id, path_to_local, std_or_core, sym};
 use hir::LifetimeKind;
 use rustc_abi::ExternAbi;
 use rustc_errors::{Applicability, MultiSpan};
@@ -18,8 +18,8 @@ use rustc_lint::{LateContext, LateLintPass};
 use rustc_middle::hir::nested_filter;
 use rustc_middle::ty::{self, Binder, ClauseKind, ExistentialPredicate, List, PredicateKind, Ty};
 use rustc_session::declare_lint_pass;
+use rustc_span::Span;
 use rustc_span::symbol::Symbol;
-use rustc_span::{Span, sym};
 use rustc_trait_selection::infer::InferCtxtExt as _;
 use rustc_trait_selection::traits::query::evaluate_obligation::InferCtxtExt as _;
 use std::{fmt, iter};
@@ -268,6 +268,7 @@ impl<'tcx> LateLintPass<'tcx> for Ptr {
                 (false, false, true) if let Some(sugg) = Sugg::hir_opt(cx, l) => sugg.maybe_paren(),
                 _ => return check_ptr_eq(cx, expr, op.node, l, r),
             };
+            let invert = if op.node == BinOpKind::Eq { "" } else { "!" };
 
             span_lint_and_sugg(
                 cx,
@@ -275,7 +276,7 @@ impl<'tcx> LateLintPass<'tcx> for Ptr {
                 expr.span,
                 "comparing with null is better expressed by the `.is_null()` method",
                 "try",
-                format!("{non_null_path_snippet}.is_null()"),
+                format!("{invert}{non_null_path_snippet}.is_null()",),
                 Applicability::MachineApplicable,
             );
         }
@@ -299,7 +300,7 @@ struct PtrArg<'tcx> {
     emission_id: HirId,
     span: Span,
     ty_name: Symbol,
-    method_renames: &'static [(&'static str, &'static str)],
+    method_renames: &'static [(Symbol, &'static str)],
     ref_prefix: RefPrefix,
     deref_ty: DerefTy<'tcx>,
 }
@@ -385,6 +386,7 @@ impl<'tcx> DerefTy<'tcx> {
     }
 }
 
+#[expect(clippy::too_many_lines)]
 fn check_fn_args<'cx, 'tcx: 'cx>(
     cx: &'cx LateContext<'tcx>,
     fn_sig: ty::FnSig<'tcx>,
@@ -409,7 +411,7 @@ fn check_fn_args<'cx, 'tcx: 'cx>(
                 let emission_id = params.get(i).map_or(hir_ty.hir_id, |param| param.hir_id);
                 let (method_renames, deref_ty) = match cx.tcx.get_diagnostic_name(adt.did()) {
                     Some(sym::Vec) => (
-                        [("clone", ".to_owned()")].as_slice(),
+                        [(sym::clone, ".to_owned()")].as_slice(),
                         DerefTy::Slice(
                             name.args.and_then(|args| args.args.first()).and_then(|arg| {
                                 if let GenericArg::Type(ty) = arg {
@@ -421,10 +423,14 @@ fn check_fn_args<'cx, 'tcx: 'cx>(
                             args.type_at(0),
                         ),
                     ),
-                    _ if Some(adt.did()) == cx.tcx.lang_items().string() => {
-                        ([("clone", ".to_owned()"), ("as_str", "")].as_slice(), DerefTy::Str)
-                    },
-                    Some(sym::PathBuf) => ([("clone", ".to_path_buf()"), ("as_path", "")].as_slice(), DerefTy::Path),
+                    _ if Some(adt.did()) == cx.tcx.lang_items().string() => (
+                        [(sym::clone, ".to_owned()"), (sym::as_str, "")].as_slice(),
+                        DerefTy::Str,
+                    ),
+                    Some(sym::PathBuf) => (
+                        [(sym::clone, ".to_path_buf()"), (sym::as_path, "")].as_slice(),
+                        DerefTy::Path,
+                    ),
                     Some(sym::Cow) if mutability == Mutability::Not => {
                         if let Some((lifetime, ty)) = name.args.and_then(|args| {
                             if let [GenericArg::Lifetime(lifetime), ty] = args.args {
@@ -595,7 +601,7 @@ fn check_ptr_arg_usage<'tcx>(cx: &LateContext<'tcx>, body: &Body<'tcx>, args: &[
                     if let ExprKind::MethodCall(name, receiver, ..) = use_expr.kind
                         && receiver.hir_id == child_id
                     {
-                        let name = name.ident.as_str();
+                        let name = name.ident.name;
 
                         // Check if the method can be renamed.
                         if let Some((_, replacement)) = args.method_renames.iter().find(|&&(x, _)| x == name) {
diff --git a/src/tools/clippy/clippy_lints/src/read_zero_byte_vec.rs b/src/tools/clippy/clippy_lints/src/read_zero_byte_vec.rs
index 49b522994fb..6b1dc864fb7 100644
--- a/src/tools/clippy/clippy_lints/src/read_zero_byte_vec.rs
+++ b/src/tools/clippy/clippy_lints/src/read_zero_byte_vec.rs
@@ -1,7 +1,7 @@
 use clippy_utils::diagnostics::{span_lint_hir, span_lint_hir_and_then};
-use clippy_utils::get_enclosing_block;
 use clippy_utils::higher::{VecInitKind, get_vec_init_kind};
 use clippy_utils::source::snippet;
+use clippy_utils::{get_enclosing_block, sym};
 
 use hir::{Expr, ExprKind, HirId, LetStmt, PatKind, PathSegment, QPath, StmtKind};
 use rustc_errors::Applicability;
@@ -87,7 +87,7 @@ impl<'tcx> LateLintPass<'tcx> for ReadZeroByteVec {
                                 diag.span_suggestion(
                                     expr.span,
                                     "try",
-                                    format!("{}.resize({len}, 0); {}", ident.as_str(), snippet(cx, expr.span, "..")),
+                                    format!("{}.resize({len}, 0); {}", ident, snippet(cx, expr.span, "..")),
                                     applicability,
                                 );
                             },
@@ -106,7 +106,7 @@ impl<'tcx> LateLintPass<'tcx> for ReadZeroByteVec {
                                         "try",
                                         format!(
                                             "{}.resize({}, 0); {}",
-                                            ident.as_str(),
+                                            ident,
                                             snippet(cx, e.span, ".."),
                                             snippet(cx, expr.span, "..")
                                         ),
@@ -142,8 +142,8 @@ impl<'tcx> Visitor<'tcx> for ReadVecVisitor<'tcx> {
         if let ExprKind::MethodCall(path, receiver, args, _) = e.kind {
             let PathSegment { ident, .. } = *path;
 
-            match ident.as_str() {
-                "read" | "read_exact" => {
+            match ident.name {
+                sym::read | sym::read_exact => {
                     let [arg] = args else { return };
                     if let ExprKind::AddrOf(_, hir::Mutability::Mut, inner) = arg.kind
                         && let ExprKind::Path(QPath::Resolved(None, inner_path)) = inner.kind
@@ -155,7 +155,7 @@ impl<'tcx> Visitor<'tcx> for ReadVecVisitor<'tcx> {
                         return;
                     }
                 },
-                "resize" => {
+                sym::resize => {
                     // If the Vec is resized, then it's a valid read
                     if let ExprKind::Path(QPath::Resolved(_, inner_path)) = receiver.kind
                         && let Res::Local(res_id) = inner_path.res
diff --git a/src/tools/clippy/clippy_lints/src/redundant_slicing.rs b/src/tools/clippy/clippy_lints/src/redundant_slicing.rs
index 1117dea703c..324a05cdcc0 100644
--- a/src/tools/clippy/clippy_lints/src/redundant_slicing.rs
+++ b/src/tools/clippy/clippy_lints/src/redundant_slicing.rs
@@ -86,7 +86,7 @@ impl<'tcx> LateLintPass<'tcx> for RedundantSlicing {
             let (indexed_ty, indexed_ref_count) = peel_middle_ty_refs(cx.typeck_results().expr_ty(indexed));
             let parent_expr = get_parent_expr(cx, expr);
             let needs_parens_for_prefix =
-                parent_expr.is_some_and(|parent| parent.precedence() > ExprPrecedence::Prefix);
+                parent_expr.is_some_and(|parent| cx.precedence(parent) > ExprPrecedence::Prefix);
 
             if expr_ty == indexed_ty {
                 if expr_ref_count > indexed_ref_count {
diff --git a/src/tools/clippy/clippy_lints/src/reserve_after_initialization.rs b/src/tools/clippy/clippy_lints/src/reserve_after_initialization.rs
index 152d7450f5f..51adbbcd58b 100644
--- a/src/tools/clippy/clippy_lints/src/reserve_after_initialization.rs
+++ b/src/tools/clippy/clippy_lints/src/reserve_after_initialization.rs
@@ -1,7 +1,7 @@
 use clippy_utils::diagnostics::span_lint_and_sugg;
 use clippy_utils::higher::{VecInitKind, get_vec_init_kind};
 use clippy_utils::source::snippet;
-use clippy_utils::{is_from_proc_macro, path_to_local_id};
+use clippy_utils::{is_from_proc_macro, path_to_local_id, sym};
 use rustc_errors::Applicability;
 use rustc_hir::def::Res;
 use rustc_hir::{BindingMode, Block, Expr, ExprKind, HirId, LetStmt, PatKind, QPath, Stmt, StmtKind};
@@ -126,7 +126,7 @@ impl<'tcx> LateLintPass<'tcx> for ReserveAfterInitialization {
             if let StmtKind::Expr(expr) | StmtKind::Semi(expr) = stmt.kind
                 && let ExprKind::MethodCall(name, self_arg, [space_hint], _) = expr.kind
                 && path_to_local_id(self_arg, searcher.local_id)
-                && name.ident.as_str() == "reserve"
+                && name.ident.name == sym::reserve
                 && !is_from_proc_macro(cx, expr)
             {
                 self.searcher = Some(VecReserveSearcher {
diff --git a/src/tools/clippy/clippy_lints/src/semicolon_block.rs b/src/tools/clippy/clippy_lints/src/semicolon_block.rs
index d85f4a8fa01..f6c128d4c52 100644
--- a/src/tools/clippy/clippy_lints/src/semicolon_block.rs
+++ b/src/tools/clippy/clippy_lints/src/semicolon_block.rs
@@ -143,7 +143,7 @@ impl LateLintPass<'_> for SemicolonBlock {
             StmtKind::Expr(Expr {
                 kind: ExprKind::Block(block, _),
                 ..
-            }) if !block.span.from_expansion() => {
+            }) if !block.span.from_expansion() && stmt.span.contains(block.span) => {
                 let Block {
                     expr: None,
                     stmts: [.., stmt],
diff --git a/src/tools/clippy/clippy_lints/src/serde_api.rs b/src/tools/clippy/clippy_lints/src/serde_api.rs
index a64b9b22378..b36a5d6d502 100644
--- a/src/tools/clippy/clippy_lints/src/serde_api.rs
+++ b/src/tools/clippy/clippy_lints/src/serde_api.rs
@@ -1,5 +1,5 @@
 use clippy_utils::diagnostics::span_lint;
-use clippy_utils::paths;
+use clippy_utils::{paths, sym};
 use rustc_hir::{Impl, Item, ItemKind};
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_session::declare_lint_pass;
@@ -36,9 +36,9 @@ impl<'tcx> LateLintPass<'tcx> for SerdeApi {
                 let mut seen_str = None;
                 let mut seen_string = None;
                 for item in *items {
-                    match item.ident.as_str() {
-                        "visit_str" => seen_str = Some(item.span),
-                        "visit_string" => seen_string = Some(item.span),
+                    match item.ident.name {
+                        sym::visit_str => seen_str = Some(item.span),
+                        sym::visit_string => seen_string = Some(item.span),
                         _ => {},
                     }
                 }
diff --git a/src/tools/clippy/clippy_lints/src/std_instead_of_core.rs b/src/tools/clippy/clippy_lints/src/std_instead_of_core.rs
index 3d39386ecf9..442b3250d86 100644
--- a/src/tools/clippy/clippy_lints/src/std_instead_of_core.rs
+++ b/src/tools/clippy/clippy_lints/src/std_instead_of_core.rs
@@ -1,13 +1,13 @@
 use clippy_config::Conf;
-use clippy_utils::diagnostics::span_lint_and_then;
+use clippy_utils::diagnostics::span_lint_and_sugg;
 use clippy_utils::is_from_proc_macro;
 use clippy_utils::msrvs::Msrv;
 use rustc_attr_data_structures::{StabilityLevel, StableSince};
 use rustc_errors::Applicability;
 use rustc_hir::def::Res;
 use rustc_hir::def_id::DefId;
-use rustc_hir::{HirId, Path, PathSegment};
-use rustc_lint::{LateContext, LateLintPass, LintContext};
+use rustc_hir::{Block, Body, HirId, Path, PathSegment};
+use rustc_lint::{LateContext, LateLintPass, Lint, LintContext};
 use rustc_session::impl_lint_pass;
 use rustc_span::symbol::kw;
 use rustc_span::{Span, sym};
@@ -88,24 +88,35 @@ declare_clippy_lint! {
 }
 
 pub struct StdReexports {
-    // Paths which can be either a module or a macro (e.g. `std::env`) will cause this check to happen
-    // twice. First for the mod, second for the macro. This is used to avoid the lint reporting for the macro
-    // when the path could be also be used to access the module.
-    prev_span: Span,
+    lint_point: (Span, Option<LintPoint>),
     msrv: Msrv,
 }
 
 impl StdReexports {
     pub fn new(conf: &'static Conf) -> Self {
         Self {
-            prev_span: Span::default(),
+            lint_point: Default::default(),
             msrv: conf.msrv,
         }
     }
+
+    fn lint_if_finish(&mut self, cx: &LateContext<'_>, (span, item): (Span, Option<LintPoint>)) {
+        if span.source_equal(self.lint_point.0) {
+            return;
+        }
+
+        if !self.lint_point.0.is_dummy() {
+            emit_lints(cx, &self.lint_point);
+        }
+
+        self.lint_point = (span, item);
+    }
 }
 
 impl_lint_pass!(StdReexports => [STD_INSTEAD_OF_CORE, STD_INSTEAD_OF_ALLOC, ALLOC_INSTEAD_OF_CORE]);
 
+type LintPoint = (&'static Lint, &'static str, &'static str);
+
 impl<'tcx> LateLintPass<'tcx> for StdReexports {
     fn check_path(&mut self, cx: &LateContext<'tcx>, path: &Path<'tcx>, _: HirId) {
         if let Res::Def(_, def_id) = path.res
@@ -119,7 +130,7 @@ impl<'tcx> LateLintPass<'tcx> for StdReexports {
                     sym::core => (STD_INSTEAD_OF_CORE, "std", "core"),
                     sym::alloc => (STD_INSTEAD_OF_ALLOC, "std", "alloc"),
                     _ => {
-                        self.prev_span = first_segment.ident.span;
+                        self.lint_if_finish(cx, (first_segment.ident.span, None));
                         return;
                     },
                 },
@@ -127,32 +138,44 @@ impl<'tcx> LateLintPass<'tcx> for StdReexports {
                     if cx.tcx.crate_name(def_id.krate) == sym::core {
                         (ALLOC_INSTEAD_OF_CORE, "alloc", "core")
                     } else {
-                        self.prev_span = first_segment.ident.span;
+                        self.lint_if_finish(cx, (first_segment.ident.span, None));
                         return;
                     }
                 },
                 _ => return,
             };
-            if first_segment.ident.span != self.prev_span {
-                #[expect(clippy::collapsible_span_lint_calls, reason = "rust-clippy#7797")]
-                span_lint_and_then(
-                    cx,
-                    lint,
-                    first_segment.ident.span,
-                    format!("used import from `{used_mod}` instead of `{replace_with}`"),
-                    |diag| {
-                        diag.span_suggestion(
-                            first_segment.ident.span,
-                            format!("consider importing the item from `{replace_with}`"),
-                            replace_with.to_string(),
-                            Applicability::MachineApplicable,
-                        );
-                    },
-                );
-                self.prev_span = first_segment.ident.span;
-            }
+
+            self.lint_if_finish(cx, (first_segment.ident.span, Some((lint, used_mod, replace_with))));
         }
     }
+
+    fn check_block_post(&mut self, cx: &LateContext<'tcx>, _: &Block<'tcx>) {
+        self.lint_if_finish(cx, Default::default());
+    }
+
+    fn check_body_post(&mut self, cx: &LateContext<'tcx>, _: &Body<'tcx>) {
+        self.lint_if_finish(cx, Default::default());
+    }
+
+    fn check_crate_post(&mut self, cx: &LateContext<'tcx>) {
+        self.lint_if_finish(cx, Default::default());
+    }
+}
+
+fn emit_lints(cx: &LateContext<'_>, (span, item): &(Span, Option<LintPoint>)) {
+    let Some((lint, used_mod, replace_with)) = item else {
+        return;
+    };
+
+    span_lint_and_sugg(
+        cx,
+        lint,
+        *span,
+        format!("used import from `{used_mod}` instead of `{replace_with}`"),
+        format!("consider importing the item from `{replace_with}`"),
+        (*replace_with).to_string(),
+        Applicability::MachineApplicable,
+    );
 }
 
 /// Returns the first named segment of a [`Path`].
diff --git a/src/tools/clippy/clippy_lints/src/strings.rs b/src/tools/clippy/clippy_lints/src/strings.rs
index 73a9fe71e00..1cda6f596f4 100644
--- a/src/tools/clippy/clippy_lints/src/strings.rs
+++ b/src/tools/clippy/clippy_lints/src/strings.rs
@@ -560,7 +560,7 @@ impl<'tcx> LateLintPass<'tcx> for TrimSplitWhitespace {
             && let Some(split_ws_def_id) = tyckres.type_dependent_def_id(expr.hir_id)
             && cx.tcx.is_diagnostic_item(sym::str_split_whitespace, split_ws_def_id)
             && let ExprKind::MethodCall(path, _trim_recv, [], trim_span) = split_recv.kind
-            && let trim_fn_name @ ("trim" | "trim_start" | "trim_end") = path.ident.name.as_str()
+            && let trim_fn_name @ (sym::trim | sym::trim_start | sym::trim_end) = path.ident.name
             && let Some(trim_def_id) = tyckres.type_dependent_def_id(split_recv.hir_id)
             && is_one_of_trim_diagnostic_items(cx, trim_def_id)
         {
diff --git a/src/tools/clippy/clippy_lints/src/swap.rs b/src/tools/clippy/clippy_lints/src/swap.rs
index e3ecd6508bf..5ecbb56925e 100644
--- a/src/tools/clippy/clippy_lints/src/swap.rs
+++ b/src/tools/clippy/clippy_lints/src/swap.rs
@@ -3,7 +3,7 @@ use clippy_utils::source::{snippet_indent, snippet_with_context};
 use clippy_utils::sugg::Sugg;
 use clippy_utils::ty::is_type_diagnostic_item;
 
-use clippy_utils::{can_mut_borrow_both, eq_expr_value, is_in_const_context, std_or_core};
+use clippy_utils::{can_mut_borrow_both, eq_expr_value, is_in_const_context, path_to_local, std_or_core};
 use itertools::Itertools;
 
 use rustc_data_structures::fx::FxIndexSet;
@@ -350,12 +350,21 @@ impl<'tcx> IndexBinding<'_, 'tcx> {
                 format!("{lhs_snippet}{rhs_snippet}")
             },
             ExprKind::Path(QPath::Resolved(_, path)) => {
-                let init = self.cx.expr_or_init(expr);
-
                 let Some(first_segment) = path.segments.first() else {
                     return String::new();
                 };
-                if !self.suggest_span.contains(init.span) || !self.is_used_other_than_swapping(first_segment.ident) {
+
+                let init = self.cx.expr_or_init(expr);
+
+                // We skip suggesting a variable binding in any of these cases:
+                // - Variable initialization is outside the suggestion span
+                // - Variable declaration is outside the suggestion span
+                // - Variable is not used as an index or elsewhere later
+                if !self.suggest_span.contains(init.span)
+                    || path_to_local(expr)
+                        .is_some_and(|hir_id| !self.suggest_span.contains(self.cx.tcx.hir_span(hir_id)))
+                    || !self.is_used_other_than_swapping(first_segment.ident)
+                {
                     return String::new();
                 }
 
diff --git a/src/tools/clippy/clippy_lints/src/transmute/missing_transmute_annotations.rs b/src/tools/clippy/clippy_lints/src/transmute/missing_transmute_annotations.rs
index 96286fcf73d..08f36a2ed5d 100644
--- a/src/tools/clippy/clippy_lints/src/transmute/missing_transmute_annotations.rs
+++ b/src/tools/clippy/clippy_lints/src/transmute/missing_transmute_annotations.rs
@@ -74,7 +74,7 @@ pub(super) fn check<'tcx>(
         last.ident.span.with_hi(path.span.hi()),
         "transmute used without annotations",
         "consider adding missing annotations",
-        format!("{}::<{from_ty}, {to_ty}>", last.ident.as_str()),
+        format!("{}::<{from_ty}, {to_ty}>", last.ident),
         Applicability::MaybeIncorrect,
     );
     true
diff --git a/src/tools/clippy/clippy_lints/src/transmute/transmutes_expressible_as_ptr_casts.rs b/src/tools/clippy/clippy_lints/src/transmute/transmutes_expressible_as_ptr_casts.rs
index 0d5cf45a5e6..18897fbb5b8 100644
--- a/src/tools/clippy/clippy_lints/src/transmute/transmutes_expressible_as_ptr_casts.rs
+++ b/src/tools/clippy/clippy_lints/src/transmute/transmutes_expressible_as_ptr_casts.rs
@@ -44,7 +44,7 @@ pub(super) fn check<'tcx>(
     };
 
     if let Node::Expr(parent) = cx.tcx.parent_hir_node(e.hir_id)
-        && parent.precedence() > ExprPrecedence::Cast
+        && cx.precedence(parent) > ExprPrecedence::Cast
     {
         sugg = format!("({sugg})");
     }
diff --git a/src/tools/clippy/clippy_lints/src/types/borrowed_box.rs b/src/tools/clippy/clippy_lints/src/types/borrowed_box.rs
index 004ad03e708..4b23367645e 100644
--- a/src/tools/clippy/clippy_lints/src/types/borrowed_box.rs
+++ b/src/tools/clippy/clippy_lints/src/types/borrowed_box.rs
@@ -33,7 +33,7 @@ pub(super) fn check(cx: &LateContext<'_>, hir_ty: &hir::Ty<'_>, lt: &Lifetime, m
                 let ltopt = if lt.is_anonymous() {
                     String::new()
                 } else {
-                    format!("{} ", lt.ident.as_str())
+                    format!("{} ", lt.ident)
                 };
 
                 if mut_ty.mutbl == Mutability::Mut {
diff --git a/src/tools/clippy/clippy_lints/src/unit_types/unit_arg.rs b/src/tools/clippy/clippy_lints/src/unit_types/unit_arg.rs
index 019ae16ca85..ae6d8a1c1aa 100644
--- a/src/tools/clippy/clippy_lints/src/unit_types/unit_arg.rs
+++ b/src/tools/clippy/clippy_lints/src/unit_types/unit_arg.rs
@@ -1,9 +1,14 @@
+use std::iter;
+
 use clippy_utils::diagnostics::span_lint_and_then;
-use clippy_utils::is_from_proc_macro;
-use clippy_utils::source::{SourceText, SpanRangeExt, indent_of, reindent_multiline};
+use clippy_utils::source::{SpanRangeExt, indent_of, reindent_multiline};
+use clippy_utils::sugg::Sugg;
+use clippy_utils::ty::expr_type_is_certain;
+use clippy_utils::{is_expr_default, is_from_proc_macro};
 use rustc_errors::Applicability;
 use rustc_hir::{Block, Expr, ExprKind, MatchSource, Node, StmtKind};
 use rustc_lint::LateContext;
+use rustc_span::SyntaxContext;
 
 use super::{UNIT_ARG, utils};
 
@@ -59,7 +64,7 @@ fn is_questionmark_desugar_marked_call(expr: &Expr<'_>) -> bool {
     }
 }
 
-fn lint_unit_args(cx: &LateContext<'_>, expr: &Expr<'_>, args_to_recover: &[&Expr<'_>]) {
+fn lint_unit_args<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'tcx>, args_to_recover: &[&'tcx Expr<'tcx>]) {
     let mut applicability = Applicability::MachineApplicable;
     let (singular, plural) = if args_to_recover.len() > 1 {
         ("", "s")
@@ -100,34 +105,41 @@ fn lint_unit_args(cx: &LateContext<'_>, expr: &Expr<'_>, args_to_recover: &[&Exp
 
             let arg_snippets: Vec<_> = args_to_recover
                 .iter()
-                .filter_map(|arg| arg.span.get_source_text(cx))
+                // If the argument is from an expansion and is a `Default::default()`, we skip it
+                .filter(|arg| !arg.span.from_expansion() || !is_expr_default_nested(cx, arg))
+                .filter_map(|arg| get_expr_snippet(cx, arg))
                 .collect();
-            let arg_snippets_without_empty_blocks: Vec<_> = args_to_recover
+
+            // If the argument is an empty block or `Default::default()`, we can replace it with `()`.
+            let arg_snippets_without_redundant_exprs: Vec<_> = args_to_recover
                 .iter()
-                .filter(|arg| !is_empty_block(arg))
-                .filter_map(|arg| arg.span.get_source_text(cx))
+                .filter(|arg| !is_expr_default_nested(cx, arg) && (arg.span.from_expansion() || !is_empty_block(arg)))
+                .filter_map(|arg| get_expr_snippet_with_type_certainty(cx, arg))
                 .collect();
 
             if let Some(call_snippet) = expr.span.get_source_text(cx) {
-                let sugg = fmt_stmts_and_call(
-                    cx,
-                    expr,
-                    &call_snippet,
-                    &arg_snippets,
-                    &arg_snippets_without_empty_blocks,
-                );
-
-                if arg_snippets_without_empty_blocks.is_empty() {
+                if arg_snippets_without_redundant_exprs.is_empty()
+                    && let suggestions = args_to_recover
+                        .iter()
+                        .filter(|arg| !arg.span.from_expansion() || !is_expr_default_nested(cx, arg))
+                        .map(|arg| (arg.span.parent_callsite().unwrap_or(arg.span), "()".to_string()))
+                        .collect::<Vec<_>>()
+                    && !suggestions.is_empty()
+                {
                     db.multipart_suggestion(
                         format!("use {singular}unit literal{plural} instead"),
-                        args_to_recover
-                            .iter()
-                            .map(|arg| (arg.span, "()".to_string()))
-                            .collect::<Vec<_>>(),
+                        suggestions,
                         applicability,
                     );
                 } else {
-                    let plural = arg_snippets_without_empty_blocks.len() > 1;
+                    let plural = arg_snippets_without_redundant_exprs.len() > 1;
+                    let sugg = fmt_stmts_and_call(
+                        cx,
+                        expr,
+                        &call_snippet,
+                        arg_snippets,
+                        arg_snippets_without_redundant_exprs,
+                    );
                     let empty_or_s = if plural { "s" } else { "" };
                     let it_or_them = if plural { "them" } else { "it" };
                     db.span_suggestion(
@@ -144,6 +156,55 @@ fn lint_unit_args(cx: &LateContext<'_>, expr: &Expr<'_>, args_to_recover: &[&Exp
     );
 }
 
+fn is_expr_default_nested<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'tcx>) -> bool {
+    is_expr_default(cx, expr)
+        || matches!(expr.kind, ExprKind::Block(block, _)
+        if block.expr.is_some() && is_expr_default_nested(cx, block.expr.unwrap()))
+}
+
+enum MaybeTypeUncertain<'tcx> {
+    Certain(Sugg<'tcx>),
+    Uncertain(Sugg<'tcx>),
+}
+
+impl From<MaybeTypeUncertain<'_>> for String {
+    fn from(value: MaybeTypeUncertain<'_>) -> Self {
+        match value {
+            MaybeTypeUncertain::Certain(sugg) => sugg.to_string(),
+            MaybeTypeUncertain::Uncertain(sugg) => format!("let _: () = {sugg}"),
+        }
+    }
+}
+
+fn get_expr_snippet<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'tcx>) -> Option<Sugg<'tcx>> {
+    let mut app = Applicability::MachineApplicable;
+    let snip = Sugg::hir_with_context(cx, expr, SyntaxContext::root(), "..", &mut app);
+    if app != Applicability::MachineApplicable {
+        return None;
+    }
+
+    Some(snip)
+}
+
+fn get_expr_snippet_with_type_certainty<'tcx>(
+    cx: &LateContext<'tcx>,
+    expr: &'tcx Expr<'tcx>,
+) -> Option<MaybeTypeUncertain<'tcx>> {
+    get_expr_snippet(cx, expr).map(|snip| {
+        // If the type of the expression is certain, we can use it directly.
+        // Otherwise, we wrap it in a `let _: () = ...` to ensure the type is correct.
+        if !expr_type_is_certain(cx, expr) && !is_block_with_no_expr(expr) {
+            MaybeTypeUncertain::Uncertain(snip)
+        } else {
+            MaybeTypeUncertain::Certain(snip)
+        }
+    })
+}
+
+fn is_block_with_no_expr(expr: &Expr<'_>) -> bool {
+    matches!(expr.kind, ExprKind::Block(Block { expr: None, .. }, _))
+}
+
 fn is_empty_block(expr: &Expr<'_>) -> bool {
     matches!(
         expr.kind,
@@ -162,23 +223,20 @@ fn fmt_stmts_and_call(
     cx: &LateContext<'_>,
     call_expr: &Expr<'_>,
     call_snippet: &str,
-    args_snippets: &[SourceText],
-    non_empty_block_args_snippets: &[SourceText],
+    args_snippets: Vec<Sugg<'_>>,
+    non_empty_block_args_snippets: Vec<MaybeTypeUncertain<'_>>,
 ) -> String {
     let call_expr_indent = indent_of(cx, call_expr.span).unwrap_or(0);
-    let call_snippet_with_replacements = args_snippets
-        .iter()
-        .fold(call_snippet.to_owned(), |acc, arg| acc.replacen(arg.as_ref(), "()", 1));
+    let call_snippet_with_replacements = args_snippets.into_iter().fold(call_snippet.to_owned(), |acc, arg| {
+        acc.replacen(&arg.to_string(), "()", 1)
+    });
 
-    let mut stmts_and_call = non_empty_block_args_snippets
-        .iter()
-        .map(|it| it.as_ref().to_owned())
-        .collect::<Vec<_>>();
-    stmts_and_call.push(call_snippet_with_replacements);
-    stmts_and_call = stmts_and_call
+    let stmts_and_call = non_empty_block_args_snippets
         .into_iter()
+        .map(Into::into)
+        .chain(iter::once(call_snippet_with_replacements))
         .map(|v| reindent_multiline(&v, true, Some(call_expr_indent)))
-        .collect();
+        .collect::<Vec<_>>();
 
     let mut stmts_and_call_snippet = stmts_and_call.join(&format!("{}{}", ";\n", " ".repeat(call_expr_indent)));
     // expr is not in a block statement or result expression position, wrap in a block
diff --git a/src/tools/clippy/clippy_lints/src/unnested_or_patterns.rs b/src/tools/clippy/clippy_lints/src/unnested_or_patterns.rs
index b839b6f5672..bd8420917f5 100644
--- a/src/tools/clippy/clippy_lints/src/unnested_or_patterns.rs
+++ b/src/tools/clippy/clippy_lints/src/unnested_or_patterns.rs
@@ -128,7 +128,7 @@ fn remove_all_parens(pat: &mut P<Pat>) {
     }
 
     impl MutVisitor for Visitor {
-        fn visit_pat(&mut self, pat: &mut P<Pat>) {
+        fn visit_pat(&mut self, pat: &mut Pat) {
             let is_inner = mem::replace(&mut self.is_inner, true);
             walk_pat(self, pat);
             let inner = match &mut pat.kind {
@@ -145,7 +145,7 @@ fn remove_all_parens(pat: &mut P<Pat>) {
 fn insert_necessary_parens(pat: &mut P<Pat>) {
     struct Visitor;
     impl MutVisitor for Visitor {
-        fn visit_pat(&mut self, pat: &mut P<Pat>) {
+        fn visit_pat(&mut self, pat: &mut Pat) {
             use ast::BindingMode;
             walk_pat(self, pat);
             let target = match &mut pat.kind {
@@ -167,7 +167,7 @@ fn unnest_or_patterns(pat: &mut P<Pat>) -> bool {
         changed: bool,
     }
     impl MutVisitor for Visitor {
-        fn visit_pat(&mut self, p: &mut P<Pat>) {
+        fn visit_pat(&mut self, p: &mut Pat) {
             // This is a bottom up transformation, so recurse first.
             walk_pat(self, p);
 
diff --git a/src/tools/clippy/clippy_lints/src/unused_io_amount.rs b/src/tools/clippy/clippy_lints/src/unused_io_amount.rs
index 5e1cb9e54f5..12cc1093899 100644
--- a/src/tools/clippy/clippy_lints/src/unused_io_amount.rs
+++ b/src/tools/clippy/clippy_lints/src/unused_io_amount.rs
@@ -1,11 +1,11 @@
 use clippy_utils::diagnostics::span_lint_hir_and_then;
 use clippy_utils::macros::{is_panic, root_macro_call_first_node};
-use clippy_utils::{is_res_lang_ctor, paths, peel_blocks};
+use clippy_utils::{is_res_lang_ctor, paths, peel_blocks, sym};
 use hir::{ExprKind, HirId, PatKind};
 use rustc_hir as hir;
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_session::declare_lint_pass;
-use rustc_span::{Span, sym};
+use rustc_span::Span;
 
 declare_clippy_lint! {
     /// ### What it does
@@ -232,8 +232,16 @@ fn is_unreachable_or_panic(cx: &LateContext<'_>, expr: &hir::Expr<'_>) -> bool {
 fn unpack_call_chain<'a>(mut expr: &'a hir::Expr<'a>) -> &'a hir::Expr<'a> {
     while let ExprKind::MethodCall(path, receiver, ..) = expr.kind {
         if matches!(
-            path.ident.as_str(),
-            "unwrap" | "expect" | "unwrap_or" | "unwrap_or_else" | "ok" | "is_ok" | "is_err" | "or_else" | "or"
+            path.ident.name,
+            sym::unwrap
+                | sym::expect
+                | sym::unwrap_or
+                | sym::unwrap_or_else
+                | sym::ok
+                | sym::is_ok
+                | sym::is_err
+                | sym::or_else
+                | sym::or
         ) {
             expr = receiver;
         } else {
diff --git a/src/tools/clippy/clippy_lints/src/unused_result_ok.rs b/src/tools/clippy/clippy_lints/src/unused_result_ok.rs
index 958f19d1833..f5ed10fb760 100644
--- a/src/tools/clippy/clippy_lints/src/unused_result_ok.rs
+++ b/src/tools/clippy/clippy_lints/src/unused_result_ok.rs
@@ -1,11 +1,11 @@
 use clippy_utils::diagnostics::span_lint_and_sugg;
 use clippy_utils::source::snippet_with_context;
+use clippy_utils::sym;
 use clippy_utils::ty::is_type_diagnostic_item;
 use rustc_errors::Applicability;
 use rustc_hir::{ExprKind, Stmt, StmtKind};
 use rustc_lint::{LateContext, LateLintPass, LintContext};
 use rustc_session::declare_lint_pass;
-use rustc_span::sym;
 
 declare_clippy_lint! {
     /// ### What it does
@@ -36,7 +36,7 @@ impl LateLintPass<'_> for UnusedResultOk {
     fn check_stmt(&mut self, cx: &LateContext<'_>, stmt: &Stmt<'_>) {
         if let StmtKind::Semi(expr) = stmt.kind
             && let ExprKind::MethodCall(ok_path, recv, [], ..) = expr.kind //check is expr.ok() has type Result<T,E>.ok(, _)
-            && ok_path.ident.as_str() == "ok"
+            && ok_path.ident.name == sym::ok
             && is_type_diagnostic_item(cx, cx.typeck_results().expr_ty(recv), sym::Result)
             && !stmt.span.in_external_macro(cx.sess().source_map())
         {
diff --git a/src/tools/clippy/clippy_lints/src/unused_unit.rs b/src/tools/clippy/clippy_lints/src/unused_unit.rs
index 9859ddfdf7b..3811f0fe6b5 100644
--- a/src/tools/clippy/clippy_lints/src/unused_unit.rs
+++ b/src/tools/clippy/clippy_lints/src/unused_unit.rs
@@ -100,7 +100,7 @@ impl<'tcx> LateLintPass<'tcx> for UnusedUnit {
         let segments = &poly.trait_ref.path.segments;
 
         if segments.len() == 1
-            && ["Fn", "FnMut", "FnOnce"].contains(&segments[0].ident.name.as_str())
+            && matches!(segments[0].ident.name, sym::Fn | sym::FnMut | sym::FnOnce)
             && let Some(args) = segments[0].args
             && args.parenthesized == GenericArgsParentheses::ParenSugar
             && let constraints = &args.constraints
@@ -109,6 +109,7 @@ impl<'tcx> LateLintPass<'tcx> for UnusedUnit {
             && let AssocItemConstraintKind::Equality { term: Term::Ty(hir_ty) } = constraints[0].kind
             && args.span_ext.hi() != poly.span.hi()
             && !hir_ty.span.from_expansion()
+            && args.span_ext.hi() != hir_ty.span.hi()
             && is_unit_ty(hir_ty)
         {
             lint_unneeded_unit_return(cx, hir_ty.span, poly.span);
diff --git a/src/tools/clippy/clippy_lints/src/vec_init_then_push.rs b/src/tools/clippy/clippy_lints/src/vec_init_then_push.rs
index 3c23662e9d1..8d873536295 100644
--- a/src/tools/clippy/clippy_lints/src/vec_init_then_push.rs
+++ b/src/tools/clippy/clippy_lints/src/vec_init_then_push.rs
@@ -2,7 +2,7 @@ use clippy_utils::diagnostics::span_lint_and_sugg;
 use clippy_utils::higher::{VecInitKind, get_vec_init_kind};
 use clippy_utils::source::snippet;
 use clippy_utils::visitors::for_each_local_use_after_expr;
-use clippy_utils::{get_parent_expr, path_to_local_id};
+use clippy_utils::{get_parent_expr, path_to_local_id, sym};
 use core::ops::ControlFlow;
 use rustc_errors::Applicability;
 use rustc_hir::def::Res;
@@ -202,7 +202,7 @@ impl<'tcx> LateLintPass<'tcx> for VecInitThenPush {
             if let StmtKind::Expr(expr) | StmtKind::Semi(expr) = stmt.kind
                 && let ExprKind::MethodCall(name, self_arg, [_], _) = expr.kind
                 && path_to_local_id(self_arg, searcher.local_id)
-                && name.ident.as_str() == "push"
+                && name.ident.name == sym::push
             {
                 self.searcher = Some(VecPushSearcher {
                     err_span: searcher.err_span.to(stmt.span),
diff --git a/src/tools/clippy/clippy_lints/src/wildcard_imports.rs b/src/tools/clippy/clippy_lints/src/wildcard_imports.rs
index 467811c586b..d9dda6eadb2 100644
--- a/src/tools/clippy/clippy_lints/src/wildcard_imports.rs
+++ b/src/tools/clippy/clippy_lints/src/wildcard_imports.rs
@@ -9,8 +9,8 @@ use rustc_hir::{Item, ItemKind, PathSegment, UseKind};
 use rustc_lint::{LateContext, LateLintPass, LintContext};
 use rustc_middle::ty;
 use rustc_session::impl_lint_pass;
+use rustc_span::BytePos;
 use rustc_span::symbol::kw;
-use rustc_span::{BytePos, sym};
 
 declare_clippy_lint! {
     /// ### What it does
@@ -193,9 +193,7 @@ impl WildcardImports {
 // Allow "...prelude::..::*" imports.
 // Many crates have a prelude, and it is imported as a glob by design.
 fn is_prelude_import(segments: &[PathSegment<'_>]) -> bool {
-    segments
-        .iter()
-        .any(|ps| ps.ident.as_str().contains(sym::prelude.as_str()))
+    segments.iter().any(|ps| ps.ident.as_str().contains("prelude"))
 }
 
 // Allow "super::*" imports in tests.
diff --git a/src/tools/clippy/clippy_lints/src/write.rs b/src/tools/clippy/clippy_lints/src/write.rs
index a8758b65c91..d9a007635ca 100644
--- a/src/tools/clippy/clippy_lints/src/write.rs
+++ b/src/tools/clippy/clippy_lints/src/write.rs
@@ -5,8 +5,8 @@ use clippy_utils::source::{SpanRangeExt, expand_past_previous_comma};
 use clippy_utils::{is_in_test, sym};
 use rustc_ast::token::LitKind;
 use rustc_ast::{
-    FormatArgPosition, FormatArgPositionKind, FormatArgs, FormatArgsPiece, FormatOptions, FormatPlaceholder,
-    FormatTrait,
+    FormatArgPosition, FormatArgPositionKind, FormatArgs, FormatArgsPiece, FormatCount, FormatOptions,
+    FormatPlaceholder, FormatTrait,
 };
 use rustc_errors::Applicability;
 use rustc_hir::{Expr, Impl, Item, ItemKind};
@@ -556,12 +556,7 @@ fn check_literal(cx: &LateContext<'_>, format_args: &FormatArgs, name: &str) {
     // Decrement the index of the remaining by the number of replaced positional arguments
     if !suggestion.is_empty() {
         for piece in &format_args.template {
-            if let Some((span, index)) = positional_arg_piece_span(piece)
-                && suggestion.iter().all(|(s, _)| *s != span)
-            {
-                let decrement = replaced_position.iter().filter(|i| **i < index).count();
-                suggestion.push((span, format!("{{{}}}", index.saturating_sub(decrement))));
-            }
+            relocalize_format_args_indexes(piece, &mut suggestion, &replaced_position);
         }
     }
 
@@ -574,7 +569,7 @@ fn check_literal(cx: &LateContext<'_>, format_args: &FormatArgs, name: &str) {
     }
 }
 
-/// Extract Span and its index from the given `piece`, iff it's positional argument.
+/// Extract Span and its index from the given `piece`, if it's positional argument.
 fn positional_arg_piece_span(piece: &FormatArgsPiece) -> Option<(Span, usize)> {
     match piece {
         FormatArgsPiece::Placeholder(FormatPlaceholder {
@@ -591,6 +586,57 @@ fn positional_arg_piece_span(piece: &FormatArgsPiece) -> Option<(Span, usize)> {
     }
 }
 
+/// Relocalizes the indexes of positional arguments in the format string
+fn relocalize_format_args_indexes(
+    piece: &FormatArgsPiece,
+    suggestion: &mut Vec<(Span, String)>,
+    replaced_position: &[usize],
+) {
+    if let FormatArgsPiece::Placeholder(FormatPlaceholder {
+        argument:
+            FormatArgPosition {
+                index: Ok(index),
+                // Only consider positional arguments
+                kind: FormatArgPositionKind::Number,
+                span: Some(span),
+            },
+        format_options,
+        ..
+    }) = piece
+    {
+        if suggestion.iter().any(|(s, _)| s.overlaps(*span)) {
+            // If the span is already in the suggestion, we don't need to process it again
+            return;
+        }
+
+        // lambda to get the decremented index based on the replaced positions
+        let decremented_index = |index: usize| -> usize {
+            let decrement = replaced_position.iter().filter(|&&i| i < index).count();
+            index - decrement
+        };
+
+        suggestion.push((*span, decremented_index(*index).to_string()));
+
+        // If there are format options, we need to handle them as well
+        if *format_options != FormatOptions::default() {
+            // lambda to process width and precision format counts and add them to the suggestion
+            let mut process_format_count = |count: &Option<FormatCount>, formatter: &dyn Fn(usize) -> String| {
+                if let Some(FormatCount::Argument(FormatArgPosition {
+                    index: Ok(format_arg_index),
+                    kind: FormatArgPositionKind::Number,
+                    span: Some(format_arg_span),
+                })) = count
+                {
+                    suggestion.push((*format_arg_span, formatter(decremented_index(*format_arg_index))));
+                }
+            };
+
+            process_format_count(&format_options.width, &|index: usize| format!("{index}$"));
+            process_format_count(&format_options.precision, &|index: usize| format!(".{index}$"));
+        }
+    }
+}
+
 /// Removes the raw marker, `#`s and quotes from a str, and returns if the literal is raw
 ///
 /// `r#"a"#` -> (`a`, true)
diff --git a/src/tools/clippy/clippy_lints/src/zombie_processes.rs b/src/tools/clippy/clippy_lints/src/zombie_processes.rs
index 09f1084fe70..6ab94a52210 100644
--- a/src/tools/clippy/clippy_lints/src/zombie_processes.rs
+++ b/src/tools/clippy/clippy_lints/src/zombie_processes.rs
@@ -5,7 +5,7 @@ use rustc_ast::Mutability;
 use rustc_ast::visit::visit_opt;
 use rustc_errors::Applicability;
 use rustc_hir::def_id::LocalDefId;
-use rustc_hir::intravisit::{Visitor, walk_block, walk_expr, walk_local};
+use rustc_hir::intravisit::{Visitor, walk_block, walk_expr};
 use rustc_hir::{Expr, ExprKind, HirId, LetStmt, Node, PatKind, Stmt, StmtKind};
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_middle::hir::nested_filter;
@@ -69,8 +69,9 @@ impl<'tcx> LateLintPass<'tcx> for ZombieProcesses {
                     let mut vis = WaitFinder {
                         cx,
                         local_id,
+                        create_id: expr.hir_id,
                         body_id: cx.tcx.hir_enclosing_body_owner(expr.hir_id),
-                        state: VisitorState::WalkUpToLocal,
+                        state: VisitorState::WalkUpToCreate,
                         early_return: None,
                         missing_wait_branch: None,
                     };
@@ -131,6 +132,7 @@ struct MaybeWait(Span);
 struct WaitFinder<'a, 'tcx> {
     cx: &'a LateContext<'tcx>,
     local_id: HirId,
+    create_id: HirId,
     body_id: LocalDefId,
     state: VisitorState,
     early_return: Option<Span>,
@@ -141,8 +143,8 @@ struct WaitFinder<'a, 'tcx> {
 
 #[derive(PartialEq)]
 enum VisitorState {
-    WalkUpToLocal,
-    LocalFound,
+    WalkUpToCreate,
+    CreateFound,
 }
 
 #[derive(Copy, Clone)]
@@ -155,19 +157,13 @@ impl<'tcx> Visitor<'tcx> for WaitFinder<'_, 'tcx> {
     type NestedFilter = nested_filter::OnlyBodies;
     type Result = ControlFlow<MaybeWait>;
 
-    fn visit_local(&mut self, l: &'tcx LetStmt<'tcx>) -> Self::Result {
-        if self.state == VisitorState::WalkUpToLocal
-            && let PatKind::Binding(_, pat_id, ..) = l.pat.kind
-            && self.local_id == pat_id
-        {
-            self.state = VisitorState::LocalFound;
+    fn visit_expr(&mut self, ex: &'tcx Expr<'tcx>) -> Self::Result {
+        if ex.hir_id == self.create_id {
+            self.state = VisitorState::CreateFound;
+            return Continue(());
         }
 
-        walk_local(self, l)
-    }
-
-    fn visit_expr(&mut self, ex: &'tcx Expr<'tcx>) -> Self::Result {
-        if self.state != VisitorState::LocalFound {
+        if self.state != VisitorState::CreateFound {
             return walk_expr(self, ex);
         }
 
diff --git a/src/tools/clippy/clippy_lints_internal/src/almost_standard_lint_formulation.rs b/src/tools/clippy/clippy_lints_internal/src/almost_standard_lint_formulation.rs
index 311f76fee6b..7eeec84720f 100644
--- a/src/tools/clippy/clippy_lints_internal/src/almost_standard_lint_formulation.rs
+++ b/src/tools/clippy/clippy_lints_internal/src/almost_standard_lint_formulation.rs
@@ -45,7 +45,7 @@ impl AlmostStandardFormulation {
 impl<'tcx> LateLintPass<'tcx> for AlmostStandardFormulation {
     fn check_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx Item<'_>) {
         let mut check_next = false;
-        if let ItemKind::Static(_, ty, Mutability::Not, _) = item.kind {
+        if let ItemKind::Static(Mutability::Not, _, ty, _) = item.kind {
             let lines = cx
                 .tcx
                 .hir_attrs(item.hir_id())
diff --git a/src/tools/clippy/clippy_lints_internal/src/lint_without_lint_pass.rs b/src/tools/clippy/clippy_lints_internal/src/lint_without_lint_pass.rs
index 0edeef3ab85..45a866030b2 100644
--- a/src/tools/clippy/clippy_lints_internal/src/lint_without_lint_pass.rs
+++ b/src/tools/clippy/clippy_lints_internal/src/lint_without_lint_pass.rs
@@ -105,7 +105,7 @@ impl_lint_pass!(LintWithoutLintPass => [
 
 impl<'tcx> LateLintPass<'tcx> for LintWithoutLintPass {
     fn check_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx Item<'_>) {
-        if let hir::ItemKind::Static(ident, ty, Mutability::Not, body_id) = item.kind {
+        if let hir::ItemKind::Static(Mutability::Not, ident, ty, body_id) = item.kind {
             if is_lint_ref_type(cx, ty) {
                 check_invalid_clippy_version_attribute(cx, item);
 
diff --git a/src/tools/clippy/clippy_utils/README.md b/src/tools/clippy/clippy_utils/README.md
index efbacbd72db..1aa16e3943c 100644
--- a/src/tools/clippy/clippy_utils/README.md
+++ b/src/tools/clippy/clippy_utils/README.md
@@ -8,7 +8,7 @@ This crate is only guaranteed to build with this `nightly` toolchain:
 
 <!-- begin autogenerated nightly -->
 ```
-nightly-2025-05-31
+nightly-2025-06-12
 ```
 <!-- end autogenerated nightly -->
 
diff --git a/src/tools/clippy/clippy_utils/src/lib.rs b/src/tools/clippy/clippy_utils/src/lib.rs
index f6ef638e618..c7a2375c8df 100644
--- a/src/tools/clippy/clippy_utils/src/lib.rs
+++ b/src/tools/clippy/clippy_utils/src/lib.rs
@@ -1793,10 +1793,9 @@ pub fn in_automatically_derived(tcx: TyCtxt<'_>, id: HirId) -> bool {
 
 /// Checks if the given `DefId` matches the `libc` item.
 pub fn match_libc_symbol(cx: &LateContext<'_>, did: DefId, name: Symbol) -> bool {
-    let path = cx.get_def_path(did);
     // libc is meant to be used as a flat list of names, but they're all actually defined in different
     // modules based on the target platform. Ignore everything but crate name and the item name.
-    path.first().is_some_and(|s| *s == sym::libc) && path.last().copied() == Some(name)
+    cx.tcx.crate_name(did.krate) == sym::libc && cx.tcx.def_path_str(did).ends_with(name.as_str())
 }
 
 /// Returns the list of condition expressions and the list of blocks in a
@@ -3473,3 +3472,15 @@ pub fn desugar_await<'tcx>(expr: &'tcx Expr<'_>) -> Option<&'tcx Expr<'tcx>> {
         None
     }
 }
+
+/// Checks if the given expression is a call to `Default::default()`.
+pub fn is_expr_default<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'tcx>) -> bool {
+    if let ExprKind::Call(fn_expr, []) = &expr.kind
+        && let ExprKind::Path(qpath) = &fn_expr.kind
+        && let Res::Def(_, def_id) = cx.qpath_res(qpath, fn_expr.hir_id)
+    {
+        cx.tcx.is_diagnostic_item(sym::default_fn, def_id)
+    } else {
+        false
+    }
+}
diff --git a/src/tools/clippy/clippy_utils/src/qualify_min_const_fn.rs b/src/tools/clippy/clippy_utils/src/qualify_min_const_fn.rs
index 8e16f943e9f..e629012b187 100644
--- a/src/tools/clippy/clippy_utils/src/qualify_min_const_fn.rs
+++ b/src/tools/clippy/clippy_utils/src/qualify_min_const_fn.rs
@@ -18,7 +18,7 @@ use rustc_middle::mir::{
 };
 use rustc_middle::traits::{BuiltinImplSource, ImplSource, ObligationCause};
 use rustc_middle::ty::adjustment::PointerCoercion;
-use rustc_middle::ty::{self, GenericArgKind, TraitRef, Ty, TyCtxt};
+use rustc_middle::ty::{self, GenericArgKind, Instance, TraitRef, Ty, TyCtxt};
 use rustc_span::Span;
 use rustc_span::symbol::sym;
 use rustc_trait_selection::traits::{ObligationCtxt, SelectionContext};
@@ -349,7 +349,15 @@ fn check_terminator<'tcx>(
         }
         | TerminatorKind::TailCall { func, args, fn_span: _ } => {
             let fn_ty = func.ty(body, cx.tcx);
-            if let ty::FnDef(fn_def_id, _) = *fn_ty.kind() {
+            if let ty::FnDef(fn_def_id, fn_substs) = fn_ty.kind() {
+                // FIXME: when analyzing a function with generic parameters, we may not have enough information to
+                // resolve to an instance. However, we could check if a host effect predicate can guarantee that
+                // this can be made a `const` call.
+                let fn_def_id = match Instance::try_resolve(cx.tcx, cx.typing_env(), *fn_def_id, fn_substs) {
+                    Ok(Some(fn_inst)) => fn_inst.def_id(),
+                    Ok(None) => return Err((span, format!("cannot resolve instance for {func:?}").into())),
+                    Err(_) => return Err((span, format!("error during instance resolution of {func:?}").into())),
+                };
                 if !is_stable_const_fn(cx, fn_def_id, msrv) {
                     return Err((
                         span,
diff --git a/src/tools/clippy/clippy_utils/src/sym.rs b/src/tools/clippy/clippy_utils/src/sym.rs
index f417530be36..3b58dba5628 100644
--- a/src/tools/clippy/clippy_utils/src/sym.rs
+++ b/src/tools/clippy/clippy_utils/src/sym.rs
@@ -76,7 +76,6 @@ generate! {
     Visitor,
     Weak,
     abs,
-    align_of,
     ambiguous_glob_reexports,
     append,
     arg,
@@ -84,6 +83,7 @@ generate! {
     as_deref,
     as_deref_mut,
     as_mut,
+    as_path,
     assert_failed,
     author,
     borrow,
@@ -121,6 +121,8 @@ generate! {
     copy_to,
     copy_to_nonoverlapping,
     count_ones,
+    create,
+    create_new,
     cycle,
     cyclomatic_complexity,
     de,
@@ -132,7 +134,6 @@ generate! {
     enum_glob_use,
     enumerate,
     err,
-    error,
     exp,
     expect_err,
     expn_data,
@@ -150,8 +151,11 @@ generate! {
     floor_char_boundary,
     fold,
     for_each,
+    from_be_bytes,
     from_bytes_with_nul,
     from_bytes_with_nul_unchecked,
+    from_le_bytes,
+    from_ne_bytes,
     from_ptr,
     from_raw,
     from_ref,
@@ -184,8 +188,10 @@ generate! {
     is_err,
     is_file,
     is_none,
+    is_none_or,
     is_ok,
     is_some,
+    is_some_and,
     isqrt,
     itertools,
     join,
@@ -252,9 +258,12 @@ generate! {
     powi,
     product,
     push,
+    read,
+    read_exact,
     read_line,
     read_to_end,
     read_to_string,
+    read_unaligned,
     redundant_pub_crate,
     regex,
     rem_euclid,
@@ -323,16 +332,22 @@ generate! {
     then_some,
     to_ascii_lowercase,
     to_ascii_uppercase,
+    to_be_bytes,
     to_digit,
+    to_le_bytes,
     to_lowercase,
+    to_ne_bytes,
     to_os_string,
     to_owned,
     to_path_buf,
     to_uppercase,
     tokio,
     trim,
+    trim_end,
     trim_end_matches,
+    trim_start,
     trim_start_matches,
+    truncate,
     unreachable_pub,
     unsafe_removed_from_name,
     unused,
@@ -347,12 +362,15 @@ generate! {
     unwrap_unchecked,
     unzip,
     utils,
+    visit_str,
+    visit_string,
     wake,
     warnings,
     wildcard_imports,
     with_capacity,
     wrapping_offset,
     write,
+    write_unaligned,
     writeln,
     zip,
 }
diff --git a/src/tools/clippy/clippy_utils/src/ty/mod.rs b/src/tools/clippy/clippy_utils/src/ty/mod.rs
index 61e70b3fa0b..32a992ccc2d 100644
--- a/src/tools/clippy/clippy_utils/src/ty/mod.rs
+++ b/src/tools/clippy/clippy_utils/src/ty/mod.rs
@@ -20,7 +20,7 @@ use rustc_middle::traits::EvaluationResult;
 use rustc_middle::ty::layout::ValidityRequirement;
 use rustc_middle::ty::{
     self, AdtDef, AliasTy, AssocItem, AssocTag, Binder, BoundRegion, FnSig, GenericArg, GenericArgKind, GenericArgsRef,
-    GenericParamDefKind, IntTy, Region, RegionKind, TraitRef, Ty, TyCtxt, TypeFoldable, TypeSuperVisitable,
+    GenericParamDefKind, IntTy, Region, RegionKind, TraitRef, Ty, TyCtxt, TypeSuperVisitable,
     TypeVisitable, TypeVisitableExt, TypeVisitor, UintTy, Upcast, VariantDef, VariantDiscr,
 };
 use rustc_span::symbol::Ident;
@@ -853,7 +853,7 @@ pub fn for_each_top_level_late_bound_region<B>(
                 ControlFlow::Continue(())
             }
         }
-        fn visit_binder<T: TypeFoldable<TyCtxt<'tcx>>>(&mut self, t: &Binder<'tcx, T>) -> Self::Result {
+        fn visit_binder<T: TypeVisitable<TyCtxt<'tcx>>>(&mut self, t: &Binder<'tcx, T>) -> Self::Result {
             self.index += 1;
             let res = t.super_visit_with(self);
             self.index -= 1;
@@ -1137,21 +1137,38 @@ impl<'tcx> InteriorMut<'tcx> {
 
     /// Check if given type has interior mutability such as [`std::cell::Cell`] or
     /// [`std::cell::RefCell`] etc. and if it does, returns a chain of types that causes
-    /// this type to be interior mutable
+    /// this type to be interior mutable.  False negatives may be expected for infinitely recursive
+    /// types, and `None` will be returned there.
     pub fn interior_mut_ty_chain(&mut self, cx: &LateContext<'tcx>, ty: Ty<'tcx>) -> Option<&'tcx ty::List<Ty<'tcx>>> {
+        self.interior_mut_ty_chain_inner(cx, ty, 0)
+    }
+
+    fn interior_mut_ty_chain_inner(
+        &mut self,
+        cx: &LateContext<'tcx>,
+        ty: Ty<'tcx>,
+        depth: usize,
+    ) -> Option<&'tcx ty::List<Ty<'tcx>>> {
+        if !cx.tcx.recursion_limit().value_within_limit(depth) {
+            return None;
+        }
+
         match self.tys.entry(ty) {
             Entry::Occupied(o) => return *o.get(),
             // Temporarily insert a `None` to break cycles
             Entry::Vacant(v) => v.insert(None),
         };
+        let depth = depth + 1;
 
         let chain = match *ty.kind() {
-            ty::RawPtr(inner_ty, _) if !self.ignore_pointers => self.interior_mut_ty_chain(cx, inner_ty),
-            ty::Ref(_, inner_ty, _) | ty::Slice(inner_ty) => self.interior_mut_ty_chain(cx, inner_ty),
+            ty::RawPtr(inner_ty, _) if !self.ignore_pointers => self.interior_mut_ty_chain_inner(cx, inner_ty, depth),
+            ty::Ref(_, inner_ty, _) | ty::Slice(inner_ty) => self.interior_mut_ty_chain_inner(cx, inner_ty, depth),
             ty::Array(inner_ty, size) if size.try_to_target_usize(cx.tcx) != Some(0) => {
-                self.interior_mut_ty_chain(cx, inner_ty)
+                self.interior_mut_ty_chain_inner(cx, inner_ty, depth)
             },
-            ty::Tuple(fields) => fields.iter().find_map(|ty| self.interior_mut_ty_chain(cx, ty)),
+            ty::Tuple(fields) => fields
+                .iter()
+                .find_map(|ty| self.interior_mut_ty_chain_inner(cx, ty, depth)),
             ty::Adt(def, _) if def.is_unsafe_cell() => Some(ty::List::empty()),
             ty::Adt(def, args) => {
                 let is_std_collection = matches!(
@@ -1171,16 +1188,17 @@ impl<'tcx> InteriorMut<'tcx> {
 
                 if is_std_collection || def.is_box() {
                     // Include the types from std collections that are behind pointers internally
-                    args.types().find_map(|ty| self.interior_mut_ty_chain(cx, ty))
+                    args.types()
+                        .find_map(|ty| self.interior_mut_ty_chain_inner(cx, ty, depth))
                 } else if self.ignored_def_ids.contains(&def.did()) || def.is_phantom_data() {
                     None
                 } else {
                     def.all_fields()
-                        .find_map(|f| self.interior_mut_ty_chain(cx, f.ty(cx.tcx, args)))
+                        .find_map(|f| self.interior_mut_ty_chain_inner(cx, f.ty(cx.tcx, args), depth))
                 }
             },
             ty::Alias(ty::Projection, _) => match cx.tcx.try_normalize_erasing_regions(cx.typing_env(), ty) {
-                Ok(normalized_ty) if ty != normalized_ty => self.interior_mut_ty_chain(cx, normalized_ty),
+                Ok(normalized_ty) if ty != normalized_ty => self.interior_mut_ty_chain_inner(cx, normalized_ty, depth),
                 _ => None,
             },
             _ => None,
@@ -1342,7 +1360,8 @@ pub fn has_non_owning_mutable_access<'tcx>(cx: &LateContext<'tcx>, iter_ty: Ty<'
                 mutability.is_mut() || !pointee_ty.is_freeze(cx.tcx, cx.typing_env())
             },
             ty::Closure(_, closure_args) => {
-                matches!(closure_args.types().next_back(), Some(captures) if has_non_owning_mutable_access_inner(cx, phantoms, captures))
+                matches!(closure_args.types().next_back(),
+                         Some(captures) if has_non_owning_mutable_access_inner(cx, phantoms, captures))
             },
             ty::Tuple(tuple_args) => tuple_args
                 .iter()
diff --git a/src/tools/clippy/rust-toolchain.toml b/src/tools/clippy/rust-toolchain.toml
index b6817d9a146..3fc5a1224a8 100644
--- a/src/tools/clippy/rust-toolchain.toml
+++ b/src/tools/clippy/rust-toolchain.toml
@@ -1,6 +1,6 @@
 [toolchain]
 # begin autogenerated nightly
-channel = "nightly-2025-05-31"
+channel = "nightly-2025-06-12"
 # end autogenerated nightly
 components = ["cargo", "llvm-tools", "rust-src", "rust-std", "rustc", "rustc-dev", "rustfmt"]
 profile = "minimal"
diff --git a/src/tools/clippy/tests/compile-test.rs b/src/tools/clippy/tests/compile-test.rs
index 78b27e2f613..99a01257a7b 100644
--- a/src/tools/clippy/tests/compile-test.rs
+++ b/src/tools/clippy/tests/compile-test.rs
@@ -273,10 +273,10 @@ fn run_ui_cargo(cx: &TestContext) {
     config.program.input_file_flag = CommandBuilder::cargo().input_file_flag;
     config.program.out_dir_flag = CommandBuilder::cargo().out_dir_flag;
     config.program.args = vec!["clippy".into(), "--color".into(), "never".into(), "--quiet".into()];
-    config
-        .program
-        .envs
-        .push(("RUSTFLAGS".into(), Some("-Dwarnings".into())));
+    config.program.envs.extend([
+        ("RUSTFLAGS".into(), Some("-Dwarnings".into())),
+        ("CARGO_INCREMENTAL".into(), Some("0".into())),
+    ]);
     // We need to do this while we still have a rustc in the `program` field.
     config.fill_host_and_target().unwrap();
     config.program.program.set_file_name(if cfg!(windows) {
diff --git a/src/tools/clippy/tests/symbols-used.rs b/src/tools/clippy/tests/symbols-used.rs
new file mode 100644
index 00000000000..bc0456711fb
--- /dev/null
+++ b/src/tools/clippy/tests/symbols-used.rs
@@ -0,0 +1,81 @@
+// This test checks that all symbols defined in Clippy's `sym.rs` file
+// are used in Clippy. Otherwise, it will fail with a list of symbols
+// which are unused.
+//
+// This test is a no-op if run as part of the compiler test suite
+// and will always succeed.
+
+use std::collections::HashSet;
+use std::ffi::OsStr;
+use std::fs;
+
+use regex::Regex;
+use walkdir::{DirEntry, WalkDir};
+
+const SYM_FILE: &str = "clippy_utils/src/sym.rs";
+
+type Result<T, E = AnyError> = std::result::Result<T, E>;
+type AnyError = Box<dyn std::error::Error>;
+
+#[test]
+#[allow(clippy::case_sensitive_file_extension_comparisons)]
+fn all_symbols_are_used() -> Result<()> {
+    if option_env!("RUSTC_TEST_SUITE").is_some() {
+        return Ok(());
+    }
+
+    // Load all symbols defined in `SYM_FILE`.
+    let content = fs::read_to_string(SYM_FILE)?;
+    let content = content
+        .split_once("generate! {")
+        .ok_or("cannot find symbols start")?
+        .1
+        .split_once("\n}\n")
+        .ok_or("cannot find symbols end")?
+        .0;
+    let mut interned: HashSet<String> = Regex::new(r"(?m)^    (\w+)")
+        .unwrap()
+        .captures_iter(content)
+        .map(|m| m[1].to_owned())
+        .collect();
+
+    // Remove symbols used as `sym::*`.
+    let used_re = Regex::new(r"\bsym::(\w+)\b").unwrap();
+    let rs_ext = OsStr::new("rs");
+    for dir in ["clippy_lints", "clippy_lints_internal", "clippy_utils", "src"] {
+        for file in WalkDir::new(dir)
+            .into_iter()
+            .flatten()
+            .map(DirEntry::into_path)
+            .filter(|p| p.extension() == Some(rs_ext))
+        {
+            for cap in used_re.captures_iter(&fs::read_to_string(file)?) {
+                interned.remove(&cap[1]);
+            }
+        }
+    }
+
+    // Remove symbols used as part of paths.
+    let paths_re = Regex::new(r"path!\(([\w:]+)\)").unwrap();
+    for path in [
+        "clippy_utils/src/paths.rs",
+        "clippy_lints_internal/src/internal_paths.rs",
+    ] {
+        for cap in paths_re.captures_iter(&fs::read_to_string(path)?) {
+            for sym in cap[1].split("::") {
+                interned.remove(sym);
+            }
+        }
+    }
+
+    let mut extra = interned.iter().collect::<Vec<_>>();
+    if !extra.is_empty() {
+        extra.sort_unstable();
+        eprintln!("Unused symbols defined in {SYM_FILE}:");
+        for sym in extra {
+            eprintln!("  - {sym}");
+        }
+        Err(format!("extra symbols found — remove them {SYM_FILE}"))?;
+    }
+    Ok(())
+}
diff --git a/src/tools/clippy/tests/ui-toml/await_holding_invalid_type/await_holding_invalid_type.rs b/src/tools/clippy/tests/ui-toml/await_holding_invalid_type/await_holding_invalid_type.rs
index 6a9a49324db..4a179cd929f 100644
--- a/src/tools/clippy/tests/ui-toml/await_holding_invalid_type/await_holding_invalid_type.rs
+++ b/src/tools/clippy/tests/ui-toml/await_holding_invalid_type/await_holding_invalid_type.rs
@@ -1,4 +1,5 @@
 #![warn(clippy::await_holding_invalid_type)]
+#![allow(clippy::ip_constant)]
 use std::net::Ipv4Addr;
 
 async fn bad() -> u32 {
diff --git a/src/tools/clippy/tests/ui-toml/await_holding_invalid_type/await_holding_invalid_type.stderr b/src/tools/clippy/tests/ui-toml/await_holding_invalid_type/await_holding_invalid_type.stderr
index deb7f49db9e..c3c88698032 100644
--- a/src/tools/clippy/tests/ui-toml/await_holding_invalid_type/await_holding_invalid_type.stderr
+++ b/src/tools/clippy/tests/ui-toml/await_holding_invalid_type/await_holding_invalid_type.stderr
@@ -1,5 +1,5 @@
 error: holding a disallowed type across an await point `std::string::String`
-  --> tests/ui-toml/await_holding_invalid_type/await_holding_invalid_type.rs:5:9
+  --> tests/ui-toml/await_holding_invalid_type/await_holding_invalid_type.rs:6:9
    |
 LL |     let _x = String::from("hello");
    |         ^^
@@ -9,13 +9,13 @@ LL |     let _x = String::from("hello");
    = help: to override `-D warnings` add `#[allow(clippy::await_holding_invalid_type)]`
 
 error: holding a disallowed type across an await point `std::net::Ipv4Addr`
-  --> tests/ui-toml/await_holding_invalid_type/await_holding_invalid_type.rs:11:9
+  --> tests/ui-toml/await_holding_invalid_type/await_holding_invalid_type.rs:12:9
    |
 LL |     let x = Ipv4Addr::new(127, 0, 0, 1);
    |         ^
 
 error: holding a disallowed type across an await point `std::string::String`
-  --> tests/ui-toml/await_holding_invalid_type/await_holding_invalid_type.rs:35:13
+  --> tests/ui-toml/await_holding_invalid_type/await_holding_invalid_type.rs:36:13
    |
 LL |         let _x = String::from("hi!");
    |             ^^
diff --git a/src/tools/clippy/tests/ui/branches_sharing_code/shared_at_bottom.rs b/src/tools/clippy/tests/ui/branches_sharing_code/shared_at_bottom.rs
index 06472a4f5d5..922d30443fc 100644
--- a/src/tools/clippy/tests/ui/branches_sharing_code/shared_at_bottom.rs
+++ b/src/tools/clippy/tests/ui/branches_sharing_code/shared_at_bottom.rs
@@ -239,3 +239,40 @@ fn fp_if_let_issue7054() {
 }
 
 fn main() {}
+
+mod issue14873 {
+    fn foo() -> i32 {
+        todo!()
+    }
+
+    macro_rules! qux {
+        ($a:ident, $b:ident, $condition:expr) => {
+            if $condition {
+                "."
+            } else {
+                ""
+            };
+            $a = foo();
+            $b = foo();
+        };
+    }
+
+    fn share_on_bottom() {
+        let mut a = 0;
+        let mut b = 0;
+        if false {
+            qux!(a, b, a == b);
+        } else {
+            qux!(a, b, a != b);
+        };
+
+        if false {
+            qux!(a, b, a == b);
+            let y = 1;
+        } else {
+            qux!(a, b, a != b);
+            let y = 1;
+            //~^ branches_sharing_code
+        }
+    }
+}
diff --git a/src/tools/clippy/tests/ui/branches_sharing_code/shared_at_bottom.stderr b/src/tools/clippy/tests/ui/branches_sharing_code/shared_at_bottom.stderr
index 648a99c65ed..f437db8b733 100644
--- a/src/tools/clippy/tests/ui/branches_sharing_code/shared_at_bottom.stderr
+++ b/src/tools/clippy/tests/ui/branches_sharing_code/shared_at_bottom.stderr
@@ -157,5 +157,20 @@ LL ~     if x == 17 { b = 1; a = 0x99; } else { }
 LL +     a = 0x99;
    |
 
-error: aborting due to 9 previous errors
+error: all if blocks contain the same code at the end
+  --> tests/ui/branches_sharing_code/shared_at_bottom.rs:274:9
+   |
+LL | /             let y = 1;
+LL | |
+LL | |         }
+   | |_________^
+   |
+   = warning: some moved values might need to be renamed to avoid wrong references
+help: consider moving these statements after the if
+   |
+LL ~         }
+LL +         let y = 1;
+   |
+
+error: aborting due to 10 previous errors
 
diff --git a/src/tools/clippy/tests/ui/branches_sharing_code/shared_at_top.rs b/src/tools/clippy/tests/ui/branches_sharing_code/shared_at_top.rs
index 694c67d4c85..dcd77679fc6 100644
--- a/src/tools/clippy/tests/ui/branches_sharing_code/shared_at_top.rs
+++ b/src/tools/clippy/tests/ui/branches_sharing_code/shared_at_top.rs
@@ -124,3 +124,34 @@ fn pf_local_with_inferred_type_issue7053() {
 }
 
 fn main() {}
+
+mod issue14873 {
+    fn foo() -> i32 {
+        todo!()
+    }
+
+    macro_rules! qux {
+        ($a:ident, $b:ident, $condition:expr) => {
+            let $a: i32 = foo();
+            let $b: i32 = foo();
+            if $condition { "." } else { "" }
+        };
+    }
+
+    fn share_on_top() {
+        if false {
+            qux!(a, b, a == b);
+        } else {
+            qux!(a, b, a != b);
+        };
+
+        if false {
+            //~^ branches_sharing_code
+            let x = 1;
+            qux!(a, b, a == b);
+        } else {
+            let x = 1;
+            qux!(a, b, a != b);
+        }
+    }
+}
diff --git a/src/tools/clippy/tests/ui/branches_sharing_code/shared_at_top.stderr b/src/tools/clippy/tests/ui/branches_sharing_code/shared_at_top.stderr
index d28e9c7af29..30efb98b3f5 100644
--- a/src/tools/clippy/tests/ui/branches_sharing_code/shared_at_top.stderr
+++ b/src/tools/clippy/tests/ui/branches_sharing_code/shared_at_top.stderr
@@ -125,5 +125,20 @@ note: the lint level is defined here
 LL | #![deny(clippy::branches_sharing_code, clippy::if_same_then_else)]
    |                                        ^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error: aborting due to 7 previous errors
+error: all if blocks contain the same code at the start
+  --> tests/ui/branches_sharing_code/shared_at_top.rs:148:9
+   |
+LL | /         if false {
+LL | |
+LL | |             let x = 1;
+   | |______________________^
+   |
+   = warning: some moved values might need to be renamed to avoid wrong references
+help: consider moving these statements before the if
+   |
+LL ~         let x = 1;
+LL +         if false {
+   |
+
+error: aborting due to 8 previous errors
 
diff --git a/src/tools/clippy/tests/ui/branches_sharing_code/shared_at_top_and_bottom.rs b/src/tools/clippy/tests/ui/branches_sharing_code/shared_at_top_and_bottom.rs
index 75334f70f1f..e848f0601e3 100644
--- a/src/tools/clippy/tests/ui/branches_sharing_code/shared_at_top_and_bottom.rs
+++ b/src/tools/clippy/tests/ui/branches_sharing_code/shared_at_top_and_bottom.rs
@@ -128,3 +128,42 @@ fn added_note_for_expression_use() -> u32 {
 }
 
 fn main() {}
+
+mod issue14873 {
+    fn foo() -> i32 {
+        todo!()
+    }
+
+    macro_rules! qux {
+        ($a:ident, $b:ident, $condition:expr) => {
+            let mut $a: i32 = foo();
+            let mut $b: i32 = foo();
+            if $condition {
+                "."
+            } else {
+                ""
+            };
+            $a = foo();
+            $b = foo();
+        };
+    }
+
+    fn share_on_top_and_bottom() {
+        if false {
+            qux!(a, b, a == b);
+        } else {
+            qux!(a, b, a != b);
+        };
+
+        if false {
+            //~^ branches_sharing_code
+            let x = 1;
+            qux!(a, b, a == b);
+            let y = 1;
+        } else {
+            let x = 1;
+            qux!(a, b, a != b);
+            let y = 1;
+        }
+    }
+}
diff --git a/src/tools/clippy/tests/ui/branches_sharing_code/shared_at_top_and_bottom.stderr b/src/tools/clippy/tests/ui/branches_sharing_code/shared_at_top_and_bottom.stderr
index 2200ab45089..40f3453edb9 100644
--- a/src/tools/clippy/tests/ui/branches_sharing_code/shared_at_top_and_bottom.stderr
+++ b/src/tools/clippy/tests/ui/branches_sharing_code/shared_at_top_and_bottom.stderr
@@ -159,5 +159,31 @@ LL ~     }
 LL +     x * 4
    |
 
-error: aborting due to 5 previous errors
+error: all if blocks contain the same code at both the start and the end
+  --> tests/ui/branches_sharing_code/shared_at_top_and_bottom.rs:158:9
+   |
+LL | /         if false {
+LL | |
+LL | |             let x = 1;
+   | |______________________^
+   |
+note: this code is shared at the end
+  --> tests/ui/branches_sharing_code/shared_at_top_and_bottom.rs:166:9
+   |
+LL | /             let y = 1;
+LL | |         }
+   | |_________^
+   = warning: some moved values might need to be renamed to avoid wrong references
+help: consider moving these statements before the if
+   |
+LL ~         let x = 1;
+LL +         if false {
+   |
+help: consider moving these statements after the if
+   |
+LL ~         }
+LL +         let y = 1;
+   |
+
+error: aborting due to 6 previous errors
 
diff --git a/src/tools/clippy/tests/ui/cmp_null.fixed b/src/tools/clippy/tests/ui/cmp_null.fixed
index 140ddb10aeb..04b8ec50160 100644
--- a/src/tools/clippy/tests/ui/cmp_null.fixed
+++ b/src/tools/clippy/tests/ui/cmp_null.fixed
@@ -33,3 +33,9 @@ fn main() {
     let _ = (x as *const ()).is_null();
     //~^ cmp_null
 }
+
+fn issue15010() {
+    let f: *mut i32 = std::ptr::null_mut();
+    debug_assert!(!f.is_null());
+    //~^ cmp_null
+}
diff --git a/src/tools/clippy/tests/ui/cmp_null.rs b/src/tools/clippy/tests/ui/cmp_null.rs
index 16ed17765da..6f7762e6ae8 100644
--- a/src/tools/clippy/tests/ui/cmp_null.rs
+++ b/src/tools/clippy/tests/ui/cmp_null.rs
@@ -33,3 +33,9 @@ fn main() {
     let _ = x as *const () == ptr::null();
     //~^ cmp_null
 }
+
+fn issue15010() {
+    let f: *mut i32 = std::ptr::null_mut();
+    debug_assert!(f != std::ptr::null_mut());
+    //~^ cmp_null
+}
diff --git a/src/tools/clippy/tests/ui/cmp_null.stderr b/src/tools/clippy/tests/ui/cmp_null.stderr
index 6821846d046..8a75b050111 100644
--- a/src/tools/clippy/tests/ui/cmp_null.stderr
+++ b/src/tools/clippy/tests/ui/cmp_null.stderr
@@ -31,5 +31,11 @@ error: comparing with null is better expressed by the `.is_null()` method
 LL |     let _ = x as *const () == ptr::null();
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `(x as *const ()).is_null()`
 
-error: aborting due to 5 previous errors
+error: comparing with null is better expressed by the `.is_null()` method
+  --> tests/ui/cmp_null.rs:39:19
+   |
+LL |     debug_assert!(f != std::ptr::null_mut());
+   |                   ^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `!f.is_null()`
+
+error: aborting due to 6 previous errors
 
diff --git a/src/tools/clippy/tests/ui/coerce_container_to_any.fixed b/src/tools/clippy/tests/ui/coerce_container_to_any.fixed
new file mode 100644
index 00000000000..ae9d3ef9656
--- /dev/null
+++ b/src/tools/clippy/tests/ui/coerce_container_to_any.fixed
@@ -0,0 +1,26 @@
+#![warn(clippy::coerce_container_to_any)]
+
+use std::any::Any;
+
+fn main() {
+    let x: Box<dyn Any> = Box::new(());
+    let ref_x = &x;
+
+    f(&*x);
+    //~^ coerce_container_to_any
+
+    f(&**ref_x);
+    //~^ coerce_container_to_any
+
+    let _: &dyn Any = &*x;
+    //~^ coerce_container_to_any
+
+    f(&42);
+    f(&Box::new(()));
+    f(&Box::new(Box::new(())));
+    f(&**ref_x);
+    f(&*x);
+    let _: &dyn Any = &*x;
+}
+
+fn f(_: &dyn Any) {}
diff --git a/src/tools/clippy/tests/ui/coerce_container_to_any.rs b/src/tools/clippy/tests/ui/coerce_container_to_any.rs
new file mode 100644
index 00000000000..9948bd48e0d
--- /dev/null
+++ b/src/tools/clippy/tests/ui/coerce_container_to_any.rs
@@ -0,0 +1,26 @@
+#![warn(clippy::coerce_container_to_any)]
+
+use std::any::Any;
+
+fn main() {
+    let x: Box<dyn Any> = Box::new(());
+    let ref_x = &x;
+
+    f(&x);
+    //~^ coerce_container_to_any
+
+    f(ref_x);
+    //~^ coerce_container_to_any
+
+    let _: &dyn Any = &x;
+    //~^ coerce_container_to_any
+
+    f(&42);
+    f(&Box::new(()));
+    f(&Box::new(Box::new(())));
+    f(&**ref_x);
+    f(&*x);
+    let _: &dyn Any = &*x;
+}
+
+fn f(_: &dyn Any) {}
diff --git a/src/tools/clippy/tests/ui/coerce_container_to_any.stderr b/src/tools/clippy/tests/ui/coerce_container_to_any.stderr
new file mode 100644
index 00000000000..00ab77e0ce0
--- /dev/null
+++ b/src/tools/clippy/tests/ui/coerce_container_to_any.stderr
@@ -0,0 +1,23 @@
+error: coercing `&std::boxed::Box<dyn std::any::Any>` to `&dyn Any`
+  --> tests/ui/coerce_container_to_any.rs:9:7
+   |
+LL |     f(&x);
+   |       ^^ help: consider dereferencing: `&*x`
+   |
+   = note: `-D clippy::coerce-container-to-any` implied by `-D warnings`
+   = help: to override `-D warnings` add `#[allow(clippy::coerce_container_to_any)]`
+
+error: coercing `&std::boxed::Box<dyn std::any::Any>` to `&dyn Any`
+  --> tests/ui/coerce_container_to_any.rs:12:7
+   |
+LL |     f(ref_x);
+   |       ^^^^^ help: consider dereferencing: `&**ref_x`
+
+error: coercing `&std::boxed::Box<dyn std::any::Any>` to `&dyn Any`
+  --> tests/ui/coerce_container_to_any.rs:15:23
+   |
+LL |     let _: &dyn Any = &x;
+   |                       ^^ help: consider dereferencing: `&*x`
+
+error: aborting due to 3 previous errors
+
diff --git a/src/tools/clippy/tests/ui/crashes/ice-14935.rs b/src/tools/clippy/tests/ui/crashes/ice-14935.rs
new file mode 100644
index 00000000000..74cda9aae53
--- /dev/null
+++ b/src/tools/clippy/tests/ui/crashes/ice-14935.rs
@@ -0,0 +1,27 @@
+//@check-pass
+#![warn(clippy::mutable_key_type)]
+
+use std::marker::PhantomData;
+
+trait Group {
+    type ExposantSet: Group;
+}
+
+struct Pow<T: Group> {
+    exposant: Box<Pow<T::ExposantSet>>,
+    _p: PhantomData<T>,
+}
+
+impl<T: Group> Pow<T> {
+    fn is_zero(&self) -> bool {
+        false
+    }
+    fn normalize(&self) {
+        #[expect(clippy::if_same_then_else)]
+        if self.is_zero() {
+        } else if false {
+        }
+    }
+}
+
+fn main() {}
diff --git a/src/tools/clippy/tests/ui/crashes/ice-9463.rs b/src/tools/clippy/tests/ui/crashes/ice-9463.rs
index 93808e0f892..cfa6cdac6fa 100644
--- a/src/tools/clippy/tests/ui/crashes/ice-9463.rs
+++ b/src/tools/clippy/tests/ui/crashes/ice-9463.rs
@@ -1,8 +1,7 @@
-#![deny(arithmetic_overflow)]
+//@check-pass
+
 fn main() {
     let _x = -1_i32 >> -1;
-    //~^ ERROR: this arithmetic operation will overflow
+    #[expect(overflowing_literals)]
     let _y = 1u32 >> 10000000000000u32;
-    //~^ ERROR: this arithmetic operation will overflow
-    //~| ERROR: literal out of range
 }
diff --git a/src/tools/clippy/tests/ui/crashes/ice-9463.stderr b/src/tools/clippy/tests/ui/crashes/ice-9463.stderr
deleted file mode 100644
index 9a3a5e444ad..00000000000
--- a/src/tools/clippy/tests/ui/crashes/ice-9463.stderr
+++ /dev/null
@@ -1,29 +0,0 @@
-error: this arithmetic operation will overflow
-  --> tests/ui/crashes/ice-9463.rs:3:14
-   |
-LL |     let _x = -1_i32 >> -1;
-   |              ^^^^^^^^^^^^ attempt to shift right by `-1_i32`, which would overflow
-   |
-note: the lint level is defined here
-  --> tests/ui/crashes/ice-9463.rs:1:9
-   |
-LL | #![deny(arithmetic_overflow)]
-   |         ^^^^^^^^^^^^^^^^^^^
-
-error: this arithmetic operation will overflow
-  --> tests/ui/crashes/ice-9463.rs:5:14
-   |
-LL |     let _y = 1u32 >> 10000000000000u32;
-   |              ^^^^^^^^^^^^^^^^^^^^^^^^^ attempt to shift right by `1316134912_u32`, which would overflow
-
-error: literal out of range for `u32`
-  --> tests/ui/crashes/ice-9463.rs:5:22
-   |
-LL |     let _y = 1u32 >> 10000000000000u32;
-   |                      ^^^^^^^^^^^^^^^^^
-   |
-   = note: the literal `10000000000000u32` does not fit into the type `u32` whose range is `0..=4294967295`
-   = note: `#[deny(overflowing_literals)]` on by default
-
-error: aborting due to 3 previous errors
-
diff --git a/src/tools/clippy/tests/ui/crashes/ice-rust-107877.rs b/src/tools/clippy/tests/ui/crashes/ice-rust-107877.rs
index 55fe418bed1..dccb0cf8ac1 100644
--- a/src/tools/clippy/tests/ui/crashes/ice-rust-107877.rs
+++ b/src/tools/clippy/tests/ui/crashes/ice-rust-107877.rs
@@ -4,6 +4,7 @@
 
 struct Foo;
 
+#[allow(clippy::infallible_try_from)]
 impl<'a> std::convert::TryFrom<&'a String> for Foo {
     type Error = std::convert::Infallible;
 
diff --git a/src/tools/clippy/tests/ui/create_dir.fixed b/src/tools/clippy/tests/ui/create_dir.fixed
index 4a5b1b77be6..d4b8f8b4d07 100644
--- a/src/tools/clippy/tests/ui/create_dir.fixed
+++ b/src/tools/clippy/tests/ui/create_dir.fixed
@@ -7,12 +7,31 @@ fn create_dir() {}
 
 fn main() {
     // Should be warned
-    create_dir_all("foo");
+    std::fs::create_dir_all("foo");
     //~^ create_dir
-    create_dir_all("bar").unwrap();
+    std::fs::create_dir_all("bar").unwrap();
     //~^ create_dir
 
     // Shouldn't be warned
     create_dir();
     std::fs::create_dir_all("foobar");
 }
+
+mod issue14994 {
+    fn with_no_prefix() {
+        use std::fs::create_dir;
+        std::fs::create_dir_all("some/dir").unwrap();
+        //~^ create_dir
+    }
+
+    fn with_fs_prefix() {
+        use std::fs;
+        fs::create_dir_all("/some/dir").unwrap();
+        //~^ create_dir
+    }
+
+    fn with_full_prefix() {
+        std::fs::create_dir_all("/some/dir").unwrap();
+        //~^ create_dir
+    }
+}
diff --git a/src/tools/clippy/tests/ui/create_dir.rs b/src/tools/clippy/tests/ui/create_dir.rs
index bf185ba3a7c..21e0bdba03b 100644
--- a/src/tools/clippy/tests/ui/create_dir.rs
+++ b/src/tools/clippy/tests/ui/create_dir.rs
@@ -16,3 +16,22 @@ fn main() {
     create_dir();
     std::fs::create_dir_all("foobar");
 }
+
+mod issue14994 {
+    fn with_no_prefix() {
+        use std::fs::create_dir;
+        create_dir("some/dir").unwrap();
+        //~^ create_dir
+    }
+
+    fn with_fs_prefix() {
+        use std::fs;
+        fs::create_dir("/some/dir").unwrap();
+        //~^ create_dir
+    }
+
+    fn with_full_prefix() {
+        std::fs::create_dir("/some/dir").unwrap();
+        //~^ create_dir
+    }
+}
diff --git a/src/tools/clippy/tests/ui/create_dir.stderr b/src/tools/clippy/tests/ui/create_dir.stderr
index 51d6ac686e0..e3ca0e7255c 100644
--- a/src/tools/clippy/tests/ui/create_dir.stderr
+++ b/src/tools/clippy/tests/ui/create_dir.stderr
@@ -8,9 +8,8 @@ LL |     std::fs::create_dir("foo");
    = help: to override `-D warnings` add `#[allow(clippy::create_dir)]`
 help: consider calling `std::fs::create_dir_all` instead
    |
-LL -     std::fs::create_dir("foo");
-LL +     create_dir_all("foo");
-   |
+LL |     std::fs::create_dir_all("foo");
+   |                        ++++
 
 error: calling `std::fs::create_dir` where there may be a better way
   --> tests/ui/create_dir.rs:12:5
@@ -20,9 +19,41 @@ LL |     std::fs::create_dir("bar").unwrap();
    |
 help: consider calling `std::fs::create_dir_all` instead
    |
-LL -     std::fs::create_dir("bar").unwrap();
-LL +     create_dir_all("bar").unwrap();
+LL |     std::fs::create_dir_all("bar").unwrap();
+   |                        ++++
+
+error: calling `std::fs::create_dir` where there may be a better way
+  --> tests/ui/create_dir.rs:23:9
+   |
+LL |         create_dir("some/dir").unwrap();
+   |         ^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: consider calling `std::fs::create_dir_all` instead
+   |
+LL |         std::fs::create_dir_all("some/dir").unwrap();
+   |         +++++++++          ++++
+
+error: calling `std::fs::create_dir` where there may be a better way
+  --> tests/ui/create_dir.rs:29:9
+   |
+LL |         fs::create_dir("/some/dir").unwrap();
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: consider calling `std::fs::create_dir_all` instead
+   |
+LL |         fs::create_dir_all("/some/dir").unwrap();
+   |                       ++++
+
+error: calling `std::fs::create_dir` where there may be a better way
+  --> tests/ui/create_dir.rs:34:9
+   |
+LL |         std::fs::create_dir("/some/dir").unwrap();
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: consider calling `std::fs::create_dir_all` instead
    |
+LL |         std::fs::create_dir_all("/some/dir").unwrap();
+   |                            ++++
 
-error: aborting due to 2 previous errors
+error: aborting due to 5 previous errors
 
diff --git a/src/tools/clippy/tests/ui/def_id_nocore.rs b/src/tools/clippy/tests/ui/def_id_nocore.rs
index 40f40f7ea09..5c13d862276 100644
--- a/src/tools/clippy/tests/ui/def_id_nocore.rs
+++ b/src/tools/clippy/tests/ui/def_id_nocore.rs
@@ -7,8 +7,14 @@
 #[link(name = "c")]
 unsafe extern "C" {}
 
+#[lang = "pointee_sized"]
+pub trait PointeeSized {}
+
+#[lang = "meta_sized"]
+pub trait MetaSized: PointeeSized {}
+
 #[lang = "sized"]
-pub trait Sized {}
+pub trait Sized: MetaSized {}
 #[lang = "copy"]
 pub trait Copy {}
 #[lang = "freeze"]
diff --git a/src/tools/clippy/tests/ui/def_id_nocore.stderr b/src/tools/clippy/tests/ui/def_id_nocore.stderr
index 2718217313f..175dd075408 100644
--- a/src/tools/clippy/tests/ui/def_id_nocore.stderr
+++ b/src/tools/clippy/tests/ui/def_id_nocore.stderr
@@ -1,5 +1,5 @@
 error: methods called `as_*` usually take `self` by reference or `self` by mutable reference
-  --> tests/ui/def_id_nocore.rs:27:19
+  --> tests/ui/def_id_nocore.rs:33:19
    |
 LL |     pub fn as_ref(self) -> &'static str {
    |                   ^^^^
diff --git a/src/tools/clippy/tests/ui/disallowed_names.rs b/src/tools/clippy/tests/ui/disallowed_names.rs
index 30fbdbc1fdc..15bb6734997 100644
--- a/src/tools/clippy/tests/ui/disallowed_names.rs
+++ b/src/tools/clippy/tests/ui/disallowed_names.rs
@@ -1,3 +1,4 @@
+//@aux-build:proc_macros.rs
 #![allow(
     dead_code,
     clippy::needless_if,
@@ -9,6 +10,9 @@
 )]
 #![warn(clippy::disallowed_names)]
 
+extern crate proc_macros;
+use proc_macros::{external, with_span};
+
 fn test(foo: ()) {}
 //~^ disallowed_names
 
@@ -66,6 +70,17 @@ fn issue_1647_ref_mut() {
     //~^ disallowed_names
 }
 
+pub fn issue_14958_proc_macro() {
+    // does not lint macro-generated code
+    external! {
+        let foo = 0;
+    }
+    with_span! {
+        span
+        let foo = 0;
+    }
+}
+
 #[cfg(test)]
 mod tests {
     fn issue_7305() {
diff --git a/src/tools/clippy/tests/ui/disallowed_names.stderr b/src/tools/clippy/tests/ui/disallowed_names.stderr
index 09398ebbab7..b43d1b3ebfa 100644
--- a/src/tools/clippy/tests/ui/disallowed_names.stderr
+++ b/src/tools/clippy/tests/ui/disallowed_names.stderr
@@ -1,5 +1,5 @@
 error: use of a disallowed/placeholder name `foo`
-  --> tests/ui/disallowed_names.rs:12:9
+  --> tests/ui/disallowed_names.rs:16:9
    |
 LL | fn test(foo: ()) {}
    |         ^^^
@@ -8,79 +8,79 @@ LL | fn test(foo: ()) {}
    = help: to override `-D warnings` add `#[allow(clippy::disallowed_names)]`
 
 error: use of a disallowed/placeholder name `foo`
-  --> tests/ui/disallowed_names.rs:16:9
+  --> tests/ui/disallowed_names.rs:20:9
    |
 LL |     let foo = 42;
    |         ^^^
 
 error: use of a disallowed/placeholder name `baz`
-  --> tests/ui/disallowed_names.rs:19:9
+  --> tests/ui/disallowed_names.rs:23:9
    |
 LL |     let baz = 42;
    |         ^^^
 
 error: use of a disallowed/placeholder name `quux`
-  --> tests/ui/disallowed_names.rs:22:9
+  --> tests/ui/disallowed_names.rs:26:9
    |
 LL |     let quux = 42;
    |         ^^^^
 
 error: use of a disallowed/placeholder name `foo`
-  --> tests/ui/disallowed_names.rs:35:10
+  --> tests/ui/disallowed_names.rs:39:10
    |
 LL |         (foo, Some(baz), quux @ Some(_)) => (),
    |          ^^^
 
 error: use of a disallowed/placeholder name `baz`
-  --> tests/ui/disallowed_names.rs:35:20
+  --> tests/ui/disallowed_names.rs:39:20
    |
 LL |         (foo, Some(baz), quux @ Some(_)) => (),
    |                    ^^^
 
 error: use of a disallowed/placeholder name `quux`
-  --> tests/ui/disallowed_names.rs:35:26
+  --> tests/ui/disallowed_names.rs:39:26
    |
 LL |         (foo, Some(baz), quux @ Some(_)) => (),
    |                          ^^^^
 
 error: use of a disallowed/placeholder name `foo`
-  --> tests/ui/disallowed_names.rs:43:19
+  --> tests/ui/disallowed_names.rs:47:19
    |
 LL | fn issue_1647(mut foo: u8) {
    |                   ^^^
 
 error: use of a disallowed/placeholder name `baz`
-  --> tests/ui/disallowed_names.rs:46:13
+  --> tests/ui/disallowed_names.rs:50:13
    |
 LL |     let mut baz = 0;
    |             ^^^
 
 error: use of a disallowed/placeholder name `quux`
-  --> tests/ui/disallowed_names.rs:49:21
+  --> tests/ui/disallowed_names.rs:53:21
    |
 LL |     if let Some(mut quux) = Some(42) {}
    |                     ^^^^
 
 error: use of a disallowed/placeholder name `baz`
-  --> tests/ui/disallowed_names.rs:54:13
+  --> tests/ui/disallowed_names.rs:58:13
    |
 LL |     let ref baz = 0;
    |             ^^^
 
 error: use of a disallowed/placeholder name `quux`
-  --> tests/ui/disallowed_names.rs:57:21
+  --> tests/ui/disallowed_names.rs:61:21
    |
 LL |     if let Some(ref quux) = Some(42) {}
    |                     ^^^^
 
 error: use of a disallowed/placeholder name `baz`
-  --> tests/ui/disallowed_names.rs:62:17
+  --> tests/ui/disallowed_names.rs:66:17
    |
 LL |     let ref mut baz = 0;
    |                 ^^^
 
 error: use of a disallowed/placeholder name `quux`
-  --> tests/ui/disallowed_names.rs:65:25
+  --> tests/ui/disallowed_names.rs:69:25
    |
 LL |     if let Some(ref mut quux) = Some(42) {}
    |                         ^^^^
diff --git a/src/tools/clippy/tests/ui/doc_suspicious_footnotes.fixed b/src/tools/clippy/tests/ui/doc_suspicious_footnotes.fixed
new file mode 100644
index 00000000000..9ed3fd4ef31
--- /dev/null
+++ b/src/tools/clippy/tests/ui/doc_suspicious_footnotes.fixed
@@ -0,0 +1,186 @@
+#![warn(clippy::doc_suspicious_footnotes)]
+#![allow(clippy::needless_raw_string_hashes)]
+//! This is not a footnote[^1].
+//!
+//! [^1]: <!-- description -->
+//~^ doc_suspicious_footnotes
+//!
+//! This is not a footnote[^either], but it doesn't warn.
+//!
+//! This is not a footnote\[^1], but it also doesn't warn.
+//!
+//! This is not a footnote[^1\], but it also doesn't warn.
+//!
+//! This is not a `footnote[^1]`, but it also doesn't warn.
+//!
+//! This is a footnote[^2].
+//!
+//! [^2]: hello world
+
+/// This is not a footnote[^1].
+///
+/// [^1]: <!-- description -->
+//~^ doc_suspicious_footnotes
+///
+/// This is not a footnote[^either], but it doesn't warn.
+///
+/// This is not a footnote\[^1], but it also doesn't warn.
+///
+/// This is not a footnote[^1\], but it also doesn't warn.
+///
+/// This is not a `footnote[^1]`, but it also doesn't warn.
+///
+/// This is a footnote[^2].
+///
+/// [^2]: hello world
+pub fn footnotes() {
+    // test code goes here
+}
+
+pub struct Foo;
+#[rustfmt::skip]
+impl Foo {
+    #[doc = r#"This is not a footnote[^1].
+
+[^1]: <!-- description -->"#]
+    //~^ doc_suspicious_footnotes
+    #[doc = r#""#]
+    #[doc = r#"This is not a footnote[^either], but it doesn't warn."#]
+    #[doc = r#""#]
+    #[doc = r#"This is not a footnote\[^1], but it also doesn't warn."#]
+    #[doc = r#""#]
+    #[doc = r#"This is not a footnote[^1\], but it also doesn't warn."#]
+    #[doc = r#""#]
+    #[doc = r#"This is not a `footnote[^1]`, but it also doesn't warn."#]
+    #[doc = r#""#]
+    #[doc = r#"This is a footnote[^2]."#]
+    #[doc = r#""#]
+    #[doc = r#"[^2]: hello world"#]
+    pub fn footnotes() {
+        // test code goes here
+    }
+    #[doc = r#"This is not a footnote[^1].
+
+    This is not a footnote[^either], but it doesn't warn.
+
+    This is not a footnote\[^1], but it also doesn't warn.
+
+    This is not a footnote[^1\], but it also doesn't warn.
+
+    This is not a `footnote[^1]`, but it also doesn't warn.
+
+    This is a footnote[^2].
+
+    [^2]: hello world
+    
+
+[^1]: <!-- description -->"#]
+    //~^^^^^^^^^^^^^^ doc_suspicious_footnotes
+    pub fn footnotes2() {
+        // test code goes here
+    }
+    #[cfg_attr(
+        not(FALSE),
+        doc = r#"This is not a footnote[^1].
+
+This is not a footnote[^either], but it doesn't warn.
+
+[^1]: <!-- description -->"#
+    //~^ doc_suspicious_footnotes
+    )]
+    pub fn footnotes3() {
+        // test code goes here
+    }
+    #[doc = "My footnote [^foot\note]"]
+    pub fn footnote4() {
+        // test code goes here
+    }
+    #[doc = "Hihi"]pub fn footnote5() {
+        // test code goes here
+    }
+}
+
+#[doc = r#"This is not a footnote[^1].
+
+[^1]: <!-- description -->"#]
+//~^ doc_suspicious_footnotes
+#[doc = r""]
+#[doc = r"This is not a footnote[^either], but it doesn't warn."]
+#[doc = r""]
+#[doc = r"This is not a footnote\[^1], but it also doesn't warn."]
+#[doc = r""]
+#[doc = r"This is not a footnote[^1\], but it also doesn't warn."]
+#[doc = r""]
+#[doc = r"This is not a `footnote[^1]`, but it also doesn't warn."]
+#[doc = r""]
+#[doc = r"This is a footnote[^2]."]
+#[doc = r""]
+#[doc = r"[^2]: hello world"]
+pub fn footnotes_attrs() {
+    // test code goes here
+}
+
+pub mod multiline {
+    /*!
+     * This is not a footnote[^1]. //~ doc_suspicious_footnotes
+     *
+     * This is not a footnote\[^1], but it doesn't warn.
+     *
+     * This is a footnote[^2].
+     *
+     * These give weird results, but correct ones, so it works.
+     *
+     * [^2]: hello world
+     */
+/*! [^1]: <!-- description --> */
+    /**
+     * This is not a footnote[^1]. //~ doc_suspicious_footnotes
+     *
+     * This is not a footnote\[^1], but it doesn't warn.
+     *
+     * This is a footnote[^2].
+     *
+     * These give weird results, but correct ones, so it works.
+     *
+     * [^2]: hello world
+     */
+/** [^1]: <!-- description --> */
+    pub fn foo() {}
+}
+
+/// This is not a footnote [^1]
+///
+/// [^1]: <!-- description -->
+//~^ doc_suspicious_footnotes
+///
+/// This one is [^2]
+///
+/// [^2]: contents
+#[doc = r#"This is not a footnote [^3]
+
+[^3]: <!-- description -->"#]
+//~^ doc_suspicious_footnotes
+#[doc = ""]
+#[doc = "This one is [^4]"]
+#[doc = ""]
+#[doc = "[^4]: contents"]
+pub struct MultiFragmentFootnote;
+
+#[doc(inline)]
+/// This is not a footnote [^5]
+///
+/// [^5]: <!-- description -->
+//~^ doc_suspicious_footnotes
+///
+/// This one is [^6]
+///
+/// [^6]: contents
+#[doc = r#"This is not a footnote [^7]
+
+[^7]: <!-- description -->"#]
+//~^ doc_suspicious_footnotes
+#[doc = ""]
+#[doc = "This one is [^8]"]
+#[doc = ""]
+#[doc = "[^8]: contents"]
+pub use MultiFragmentFootnote as OtherInlinedFootnote;
diff --git a/src/tools/clippy/tests/ui/doc_suspicious_footnotes.rs b/src/tools/clippy/tests/ui/doc_suspicious_footnotes.rs
new file mode 100644
index 00000000000..9a8d0dcf475
--- /dev/null
+++ b/src/tools/clippy/tests/ui/doc_suspicious_footnotes.rs
@@ -0,0 +1,162 @@
+#![warn(clippy::doc_suspicious_footnotes)]
+#![allow(clippy::needless_raw_string_hashes)]
+//! This is not a footnote[^1].
+//~^ doc_suspicious_footnotes
+//!
+//! This is not a footnote[^either], but it doesn't warn.
+//!
+//! This is not a footnote\[^1], but it also doesn't warn.
+//!
+//! This is not a footnote[^1\], but it also doesn't warn.
+//!
+//! This is not a `footnote[^1]`, but it also doesn't warn.
+//!
+//! This is a footnote[^2].
+//!
+//! [^2]: hello world
+
+/// This is not a footnote[^1].
+//~^ doc_suspicious_footnotes
+///
+/// This is not a footnote[^either], but it doesn't warn.
+///
+/// This is not a footnote\[^1], but it also doesn't warn.
+///
+/// This is not a footnote[^1\], but it also doesn't warn.
+///
+/// This is not a `footnote[^1]`, but it also doesn't warn.
+///
+/// This is a footnote[^2].
+///
+/// [^2]: hello world
+pub fn footnotes() {
+    // test code goes here
+}
+
+pub struct Foo;
+#[rustfmt::skip]
+impl Foo {
+    #[doc = r#"This is not a footnote[^1]."#]
+    //~^ doc_suspicious_footnotes
+    #[doc = r#""#]
+    #[doc = r#"This is not a footnote[^either], but it doesn't warn."#]
+    #[doc = r#""#]
+    #[doc = r#"This is not a footnote\[^1], but it also doesn't warn."#]
+    #[doc = r#""#]
+    #[doc = r#"This is not a footnote[^1\], but it also doesn't warn."#]
+    #[doc = r#""#]
+    #[doc = r#"This is not a `footnote[^1]`, but it also doesn't warn."#]
+    #[doc = r#""#]
+    #[doc = r#"This is a footnote[^2]."#]
+    #[doc = r#""#]
+    #[doc = r#"[^2]: hello world"#]
+    pub fn footnotes() {
+        // test code goes here
+    }
+    #[doc = "This is not a footnote[^1].
+
+    This is not a footnote[^either], but it doesn't warn.
+
+    This is not a footnote\\[^1], but it also doesn't warn.
+
+    This is not a footnote[^1\\], but it also doesn't warn.
+
+    This is not a `footnote[^1]`, but it also doesn't warn.
+
+    This is a footnote[^2].
+
+    [^2]: hello world
+    "]
+    //~^^^^^^^^^^^^^^ doc_suspicious_footnotes
+    pub fn footnotes2() {
+        // test code goes here
+    }
+    #[cfg_attr(
+        not(FALSE),
+        doc = "This is not a footnote[^1].\n\nThis is not a footnote[^either], but it doesn't warn."
+    //~^ doc_suspicious_footnotes
+    )]
+    pub fn footnotes3() {
+        // test code goes here
+    }
+    #[doc = "My footnote [^foot\note]"]
+    pub fn footnote4() {
+        // test code goes here
+    }
+    #[doc = "Hihi"]pub fn footnote5() {
+        // test code goes here
+    }
+}
+
+#[doc = r"This is not a footnote[^1]."]
+//~^ doc_suspicious_footnotes
+#[doc = r""]
+#[doc = r"This is not a footnote[^either], but it doesn't warn."]
+#[doc = r""]
+#[doc = r"This is not a footnote\[^1], but it also doesn't warn."]
+#[doc = r""]
+#[doc = r"This is not a footnote[^1\], but it also doesn't warn."]
+#[doc = r""]
+#[doc = r"This is not a `footnote[^1]`, but it also doesn't warn."]
+#[doc = r""]
+#[doc = r"This is a footnote[^2]."]
+#[doc = r""]
+#[doc = r"[^2]: hello world"]
+pub fn footnotes_attrs() {
+    // test code goes here
+}
+
+pub mod multiline {
+    /*!
+     * This is not a footnote[^1]. //~ doc_suspicious_footnotes
+     *
+     * This is not a footnote\[^1], but it doesn't warn.
+     *
+     * This is a footnote[^2].
+     *
+     * These give weird results, but correct ones, so it works.
+     *
+     * [^2]: hello world
+     */
+    /**
+     * This is not a footnote[^1]. //~ doc_suspicious_footnotes
+     *
+     * This is not a footnote\[^1], but it doesn't warn.
+     *
+     * This is a footnote[^2].
+     *
+     * These give weird results, but correct ones, so it works.
+     *
+     * [^2]: hello world
+     */
+    pub fn foo() {}
+}
+
+/// This is not a footnote [^1]
+//~^ doc_suspicious_footnotes
+///
+/// This one is [^2]
+///
+/// [^2]: contents
+#[doc = "This is not a footnote [^3]"]
+//~^ doc_suspicious_footnotes
+#[doc = ""]
+#[doc = "This one is [^4]"]
+#[doc = ""]
+#[doc = "[^4]: contents"]
+pub struct MultiFragmentFootnote;
+
+#[doc(inline)]
+/// This is not a footnote [^5]
+//~^ doc_suspicious_footnotes
+///
+/// This one is [^6]
+///
+/// [^6]: contents
+#[doc = "This is not a footnote [^7]"]
+//~^ doc_suspicious_footnotes
+#[doc = ""]
+#[doc = "This one is [^8]"]
+#[doc = ""]
+#[doc = "[^8]: contents"]
+pub use MultiFragmentFootnote as OtherInlinedFootnote;
diff --git a/src/tools/clippy/tests/ui/doc_suspicious_footnotes.stderr b/src/tools/clippy/tests/ui/doc_suspicious_footnotes.stderr
new file mode 100644
index 00000000000..4f920f37a62
--- /dev/null
+++ b/src/tools/clippy/tests/ui/doc_suspicious_footnotes.stderr
@@ -0,0 +1,179 @@
+error: looks like a footnote ref, but has no matching footnote
+  --> tests/ui/doc_suspicious_footnotes.rs:3:27
+   |
+LL | //! This is not a footnote[^1].
+   |                           ^^^^
+   |
+   = note: `-D clippy::doc-suspicious-footnotes` implied by `-D warnings`
+   = help: to override `-D warnings` add `#[allow(clippy::doc_suspicious_footnotes)]`
+help: add footnote definition
+   |
+LL ~ //! This is not a footnote[^1].
+LL + //!
+LL + //! [^1]: <!-- description -->
+   |
+
+error: looks like a footnote ref, but has no matching footnote
+  --> tests/ui/doc_suspicious_footnotes.rs:18:27
+   |
+LL | /// This is not a footnote[^1].
+   |                           ^^^^
+   |
+help: add footnote definition
+   |
+LL ~ /// This is not a footnote[^1].
+LL + ///
+LL + /// [^1]: <!-- description -->
+   |
+
+error: looks like a footnote ref, but has no matching footnote
+  --> tests/ui/doc_suspicious_footnotes.rs:39:13
+   |
+LL |     #[doc = r#"This is not a footnote[^1]."#]
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: add footnote definition
+   |
+LL ~     #[doc = r#"This is not a footnote[^1].
+LL + 
+LL ~ [^1]: <!-- description -->"#]
+   |
+
+error: looks like a footnote ref, but has no matching footnote
+  --> tests/ui/doc_suspicious_footnotes.rs:56:13
+   |
+LL |       #[doc = "This is not a footnote[^1].
+   |  _____________^
+LL | |
+LL | |     This is not a footnote[^either], but it doesn't warn.
+...  |
+LL | |     [^2]: hello world
+LL | |     "]
+   | |_____^
+   |
+help: add footnote definition
+   |
+LL ~     #[doc = r#"This is not a footnote[^1].
+LL + 
+LL +     This is not a footnote[^either], but it doesn't warn.
+LL + 
+LL +     This is not a footnote\[^1], but it also doesn't warn.
+LL + 
+LL +     This is not a footnote[^1\], but it also doesn't warn.
+LL + 
+LL +     This is not a `footnote[^1]`, but it also doesn't warn.
+LL + 
+LL +     This is a footnote[^2].
+LL + 
+LL +     [^2]: hello world
+LL +     
+LL + 
+LL ~ [^1]: <!-- description -->"#]
+   |
+
+error: looks like a footnote ref, but has no matching footnote
+  --> tests/ui/doc_suspicious_footnotes.rs:76:38
+   |
+LL |         doc = "This is not a footnote[^1].\n\nThis is not a footnote[^either], but it doesn't warn."
+   |                                      ^^^^
+   |
+help: add footnote definition
+   |
+LL ~         doc = r#"This is not a footnote[^1].
+LL + 
+LL + This is not a footnote[^either], but it doesn't warn.
+LL + 
+LL + [^1]: <!-- description -->"#
+   |
+
+error: looks like a footnote ref, but has no matching footnote
+  --> tests/ui/doc_suspicious_footnotes.rs:91:9
+   |
+LL | #[doc = r"This is not a footnote[^1]."]
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: add footnote definition
+   |
+LL ~ #[doc = r#"This is not a footnote[^1].
+LL + 
+LL ~ [^1]: <!-- description -->"#]
+   |
+
+error: looks like a footnote ref, but has no matching footnote
+  --> tests/ui/doc_suspicious_footnotes.rs:111:30
+   |
+LL |      * This is not a footnote[^1].
+   |                              ^^^^
+   |
+help: add footnote definition
+   |
+LL ~      */
+LL + /*! [^1]: <!-- description --> */
+   |
+
+error: looks like a footnote ref, but has no matching footnote
+  --> tests/ui/doc_suspicious_footnotes.rs:122:30
+   |
+LL |      * This is not a footnote[^1].
+   |                              ^^^^
+   |
+help: add footnote definition
+   |
+LL ~      */
+LL + /** [^1]: <!-- description --> */
+   |
+
+error: looks like a footnote ref, but has no matching footnote
+  --> tests/ui/doc_suspicious_footnotes.rs:135:28
+   |
+LL | /// This is not a footnote [^1]
+   |                            ^^^^
+   |
+help: add footnote definition
+   |
+LL ~ /// This is not a footnote [^1]
+LL + ///
+LL + /// [^1]: <!-- description -->
+   |
+
+error: looks like a footnote ref, but has no matching footnote
+  --> tests/ui/doc_suspicious_footnotes.rs:141:33
+   |
+LL | #[doc = "This is not a footnote [^3]"]
+   |                                 ^^^^
+   |
+help: add footnote definition
+   |
+LL ~ #[doc = r#"This is not a footnote [^3]
+LL + 
+LL ~ [^3]: <!-- description -->"#]
+   |
+
+error: looks like a footnote ref, but has no matching footnote
+  --> tests/ui/doc_suspicious_footnotes.rs:150:28
+   |
+LL | /// This is not a footnote [^5]
+   |                            ^^^^
+   |
+help: add footnote definition
+   |
+LL ~ /// This is not a footnote [^5]
+LL + ///
+LL + /// [^5]: <!-- description -->
+   |
+
+error: looks like a footnote ref, but has no matching footnote
+  --> tests/ui/doc_suspicious_footnotes.rs:156:33
+   |
+LL | #[doc = "This is not a footnote [^7]"]
+   |                                 ^^^^
+   |
+help: add footnote definition
+   |
+LL ~ #[doc = r#"This is not a footnote [^7]
+LL + 
+LL ~ [^7]: <!-- description -->"#]
+   |
+
+error: aborting due to 12 previous errors
+
diff --git a/src/tools/clippy/tests/ui/doc_suspicious_footnotes_include.rs b/src/tools/clippy/tests/ui/doc_suspicious_footnotes_include.rs
new file mode 100644
index 00000000000..4f75ad94eaf
--- /dev/null
+++ b/src/tools/clippy/tests/ui/doc_suspicious_footnotes_include.rs
@@ -0,0 +1,4 @@
+//@ error-in-other-file: footnote
+//@ no-rustfix
+#![warn(clippy::doc_suspicious_footnotes)]
+#![doc=include_str!("doc_suspicious_footnotes_include.txt")]
diff --git a/src/tools/clippy/tests/ui/doc_suspicious_footnotes_include.stderr b/src/tools/clippy/tests/ui/doc_suspicious_footnotes_include.stderr
new file mode 100644
index 00000000000..74154e3f4ef
--- /dev/null
+++ b/src/tools/clippy/tests/ui/doc_suspicious_footnotes_include.stderr
@@ -0,0 +1,17 @@
+error: looks like a footnote ref, but has no matching footnote
+  --> tests/ui/doc_suspicious_footnotes_include.txt:1:23
+   |
+LL | This is not a footnote[^1].
+   |                       ^^^^
+   |
+   = note: `-D clippy::doc-suspicious-footnotes` implied by `-D warnings`
+   = help: to override `-D warnings` add `#[allow(clippy::doc_suspicious_footnotes)]`
+help: add footnote definition
+   |
+LL ~ [^2]: hello world
+LL + 
+LL + [^1]: <!-- description -->
+   |
+
+error: aborting due to 1 previous error
+
diff --git a/src/tools/clippy/tests/ui/doc_suspicious_footnotes_include.txt b/src/tools/clippy/tests/ui/doc_suspicious_footnotes_include.txt
new file mode 100644
index 00000000000..2a533e32c4a
--- /dev/null
+++ b/src/tools/clippy/tests/ui/doc_suspicious_footnotes_include.txt
@@ -0,0 +1,13 @@
+This is not a footnote[^1]. //~ doc_suspicious_footnotes
+
+This is not a footnote[^either], but it doesn't warn.
+
+This is not a footnote\[^1], but it also doesn't warn.
+
+This is not a footnote[^1\], but it also doesn't warn.
+
+This is not a `footnote[^1]`, but it also doesn't warn.
+
+This is a footnote[^2].
+
+[^2]: hello world
diff --git a/src/tools/clippy/tests/ui/format_args.fixed b/src/tools/clippy/tests/ui/format_args.fixed
index edfdaa23ca1..3cb6c0b4d97 100644
--- a/src/tools/clippy/tests/ui/format_args.fixed
+++ b/src/tools/clippy/tests/ui/format_args.fixed
@@ -192,3 +192,13 @@ mod issue_9256 {
         print_substring("Hello, world!");
     }
 }
+
+mod issue14952 {
+    use std::path::Path;
+    struct Foo(Path);
+    impl std::fmt::Debug for Foo {
+        fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+            write!(f, "{:?}", &self.0)
+        }
+    }
+}
diff --git a/src/tools/clippy/tests/ui/format_args.rs b/src/tools/clippy/tests/ui/format_args.rs
index 367560d577d..8a9c369fff3 100644
--- a/src/tools/clippy/tests/ui/format_args.rs
+++ b/src/tools/clippy/tests/ui/format_args.rs
@@ -192,3 +192,13 @@ mod issue_9256 {
         print_substring("Hello, world!");
     }
 }
+
+mod issue14952 {
+    use std::path::Path;
+    struct Foo(Path);
+    impl std::fmt::Debug for Foo {
+        fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+            write!(f, "{:?}", &self.0)
+        }
+    }
+}
diff --git a/src/tools/clippy/tests/ui/indexing_slicing_index.rs b/src/tools/clippy/tests/ui/indexing_slicing_index.rs
index ab6a8235008..2510a023acd 100644
--- a/src/tools/clippy/tests/ui/indexing_slicing_index.rs
+++ b/src/tools/clippy/tests/ui/indexing_slicing_index.rs
@@ -68,7 +68,6 @@ fn main() {
     // This should be linted, since `suppress-restriction-lint-in-const` default is false.
     const { &ARR[idx4()] };
     //~^ ERROR: indexing may panic
-    //~| ERROR: index out of bounds
 
     let y = &x;
     // Ok, referencing shouldn't affect this lint. See the issue 6021
diff --git a/src/tools/clippy/tests/ui/indexing_slicing_index.stderr b/src/tools/clippy/tests/ui/indexing_slicing_index.stderr
index 8e24b898ed5..c68e1d53a93 100644
--- a/src/tools/clippy/tests/ui/indexing_slicing_index.stderr
+++ b/src/tools/clippy/tests/ui/indexing_slicing_index.stderr
@@ -9,18 +9,6 @@ LL | const REF: &i32 = &ARR[idx()]; // This should be linted, since `suppress-re
    = note: `-D clippy::indexing-slicing` implied by `-D warnings`
    = help: to override `-D warnings` add `#[allow(clippy::indexing_slicing)]`
 
-error[E0080]: index out of bounds: the length is 2 but the index is 4
-  --> tests/ui/indexing_slicing_index.rs:69:14
-   |
-LL |     const { &ARR[idx4()] };
-   |              ^^^^^^^^^^^ evaluation of `main::{constant#3}` failed here
-
-note: erroneous constant encountered
-  --> tests/ui/indexing_slicing_index.rs:69:5
-   |
-LL |     const { &ARR[idx4()] };
-   |     ^^^^^^^^^^^^^^^^^^^^^^
-
 error: indexing may panic
   --> tests/ui/indexing_slicing_index.rs:48:5
    |
@@ -63,13 +51,13 @@ LL |     const { &ARR[idx4()] };
    = note: the suggestion might not be applicable in constant blocks
 
 error: index is out of bounds
-  --> tests/ui/indexing_slicing_index.rs:77:5
+  --> tests/ui/indexing_slicing_index.rs:76:5
    |
 LL |     y[4];
    |     ^^^^
 
 error: indexing may panic
-  --> tests/ui/indexing_slicing_index.rs:81:5
+  --> tests/ui/indexing_slicing_index.rs:80:5
    |
 LL |     v[0];
    |     ^^^^
@@ -77,7 +65,7 @@ LL |     v[0];
    = help: consider using `.get(n)` or `.get_mut(n)` instead
 
 error: indexing may panic
-  --> tests/ui/indexing_slicing_index.rs:83:5
+  --> tests/ui/indexing_slicing_index.rs:82:5
    |
 LL |     v[10];
    |     ^^^^^
@@ -85,7 +73,7 @@ LL |     v[10];
    = help: consider using `.get(n)` or `.get_mut(n)` instead
 
 error: indexing may panic
-  --> tests/ui/indexing_slicing_index.rs:85:5
+  --> tests/ui/indexing_slicing_index.rs:84:5
    |
 LL |     v[1 << 3];
    |     ^^^^^^^^^
@@ -93,13 +81,13 @@ LL |     v[1 << 3];
    = help: consider using `.get(n)` or `.get_mut(n)` instead
 
 error: index is out of bounds
-  --> tests/ui/indexing_slicing_index.rs:93:5
+  --> tests/ui/indexing_slicing_index.rs:92:5
    |
 LL |     x[N];
    |     ^^^^
 
 error: indexing may panic
-  --> tests/ui/indexing_slicing_index.rs:97:5
+  --> tests/ui/indexing_slicing_index.rs:96:5
    |
 LL |     v[N];
    |     ^^^^
@@ -107,7 +95,7 @@ LL |     v[N];
    = help: consider using `.get(n)` or `.get_mut(n)` instead
 
 error: indexing may panic
-  --> tests/ui/indexing_slicing_index.rs:99:5
+  --> tests/ui/indexing_slicing_index.rs:98:5
    |
 LL |     v[M];
    |     ^^^^
@@ -115,11 +103,10 @@ LL |     v[M];
    = help: consider using `.get(n)` or `.get_mut(n)` instead
 
 error: index is out of bounds
-  --> tests/ui/indexing_slicing_index.rs:103:13
+  --> tests/ui/indexing_slicing_index.rs:102:13
    |
 LL |     let _ = x[4];
    |             ^^^^
 
-error: aborting due to 15 previous errors
+error: aborting due to 14 previous errors
 
-For more information about this error, try `rustc --explain E0080`.
diff --git a/src/tools/clippy/tests/ui/infallible_try_from.rs b/src/tools/clippy/tests/ui/infallible_try_from.rs
new file mode 100644
index 00000000000..6a1f12f824f
--- /dev/null
+++ b/src/tools/clippy/tests/ui/infallible_try_from.rs
@@ -0,0 +1,33 @@
+#![feature(never_type)]
+#![warn(clippy::infallible_try_from)]
+
+use std::convert::Infallible;
+
+struct MyStruct(i32);
+
+impl TryFrom<i8> for MyStruct {
+    //~^ infallible_try_from
+    type Error = !;
+    fn try_from(other: i8) -> Result<Self, !> {
+        Ok(Self(other.into()))
+    }
+}
+
+impl TryFrom<i16> for MyStruct {
+    //~^ infallible_try_from
+    type Error = Infallible;
+    fn try_from(other: i16) -> Result<Self, Infallible> {
+        Ok(Self(other.into()))
+    }
+}
+
+impl TryFrom<i64> for MyStruct {
+    type Error = i64;
+    fn try_from(other: i64) -> Result<Self, i64> {
+        Ok(Self(i32::try_from(other).map_err(|_| other)?))
+    }
+}
+
+fn main() {
+    // test code goes here
+}
diff --git a/src/tools/clippy/tests/ui/infallible_try_from.stderr b/src/tools/clippy/tests/ui/infallible_try_from.stderr
new file mode 100644
index 00000000000..705b1188489
--- /dev/null
+++ b/src/tools/clippy/tests/ui/infallible_try_from.stderr
@@ -0,0 +1,23 @@
+error: infallible TryFrom impl; consider implementing From, instead
+  --> tests/ui/infallible_try_from.rs:8:1
+   |
+LL | impl TryFrom<i8> for MyStruct {
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+LL |
+LL |     type Error = !;
+   |                  - infallible error type
+   |
+   = note: `-D clippy::infallible-try-from` implied by `-D warnings`
+   = help: to override `-D warnings` add `#[allow(clippy::infallible_try_from)]`
+
+error: infallible TryFrom impl; consider implementing From, instead
+  --> tests/ui/infallible_try_from.rs:16:1
+   |
+LL | impl TryFrom<i16> for MyStruct {
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+LL |
+LL |     type Error = Infallible;
+   |                  ---------- infallible error type
+
+error: aborting due to 2 previous errors
+
diff --git a/src/tools/clippy/tests/ui/ip_constant.fixed b/src/tools/clippy/tests/ui/ip_constant.fixed
new file mode 100644
index 00000000000..2e3389c1193
--- /dev/null
+++ b/src/tools/clippy/tests/ui/ip_constant.fixed
@@ -0,0 +1,107 @@
+#![warn(clippy::ip_constant)]
+#![allow(dead_code)]
+#![allow(clippy::identity_op)]
+#![allow(clippy::eq_op)]
+
+fn literal_test1() {
+    use std::net::Ipv4Addr;
+    let _ = Ipv4Addr::LOCALHOST;
+    //~^ ip_constant
+    let _ = Ipv4Addr::BROADCAST;
+    //~^ ip_constant
+    let _ = Ipv4Addr::UNSPECIFIED;
+    //~^ ip_constant
+
+    use std::net::Ipv6Addr;
+    let _ = Ipv6Addr::LOCALHOST;
+    //~^ ip_constant
+    let _ = Ipv6Addr::UNSPECIFIED;
+    //~^ ip_constant
+}
+
+fn literal_test2() {
+    use std::net;
+    let _ = net::Ipv4Addr::LOCALHOST;
+    //~^ ip_constant
+    let _ = net::Ipv4Addr::BROADCAST;
+    //~^ ip_constant
+    let _ = net::Ipv4Addr::UNSPECIFIED;
+    //~^ ip_constant
+
+    let _ = net::Ipv6Addr::LOCALHOST;
+    //~^ ip_constant
+    let _ = net::Ipv6Addr::UNSPECIFIED;
+    //~^ ip_constant
+}
+
+fn literal_test3() {
+    let _ = std::net::Ipv4Addr::LOCALHOST;
+    //~^ ip_constant
+    let _ = std::net::Ipv4Addr::BROADCAST;
+    //~^ ip_constant
+    let _ = std::net::Ipv4Addr::UNSPECIFIED;
+    //~^ ip_constant
+
+    let _ = std::net::Ipv6Addr::LOCALHOST;
+    //~^ ip_constant
+    let _ = std::net::Ipv6Addr::UNSPECIFIED;
+    //~^ ip_constant
+}
+
+const CONST_U8_0: u8 = 0;
+const CONST_U8_1: u8 = 1;
+const CONST_U8_127: u8 = 127;
+const CONST_U8_255: u8 = 255;
+
+const CONST_U16_0: u16 = 0;
+const CONST_U16_1: u16 = 1;
+
+fn const_test1() {
+    use std::net::Ipv4Addr;
+    let _ = Ipv4Addr::LOCALHOST;
+    //~^ ip_constant
+    let _ = Ipv4Addr::BROADCAST;
+    //~^ ip_constant
+    let _ = Ipv4Addr::UNSPECIFIED;
+    //~^ ip_constant
+
+    use std::net::Ipv6Addr;
+    let _ = Ipv6Addr::LOCALHOST;
+
+    let _ = Ipv6Addr::UNSPECIFIED;
+}
+
+fn const_test2() {
+    use std::net::Ipv4Addr;
+    let _ = Ipv4Addr::LOCALHOST;
+    //~^ ip_constant
+    let _ = Ipv4Addr::BROADCAST;
+    //~^ ip_constant
+    let _ = Ipv4Addr::UNSPECIFIED;
+    //~^ ip_constant
+
+    use std::net::Ipv6Addr;
+    let _ = Ipv6Addr::LOCALHOST;
+    //~^ ip_constant
+    let _ = Ipv6Addr::LOCALHOST;
+    //~^ ip_constant
+}
+
+macro_rules! ipv4_new {
+    ($a:expr, $b:expr, $c:expr, $d:expr) => {
+        std::net::Ipv4Addr::new($a, $b, $c, $d)
+    };
+}
+
+fn macro_test() {
+    let _ = ipv4_new!(127, 0, 0, 1);
+    // no lint
+    let _ = ipv4_new!(255, 255, 255, 255);
+    // no lint
+    let _ = ipv4_new!(0, 0, 0, 0);
+    // no lint
+}
+
+fn main() {
+    // UI Test
+}
diff --git a/src/tools/clippy/tests/ui/ip_constant.rs b/src/tools/clippy/tests/ui/ip_constant.rs
new file mode 100644
index 00000000000..15e0b0551ba
--- /dev/null
+++ b/src/tools/clippy/tests/ui/ip_constant.rs
@@ -0,0 +1,127 @@
+#![warn(clippy::ip_constant)]
+#![allow(dead_code)]
+#![allow(clippy::identity_op)]
+#![allow(clippy::eq_op)]
+
+fn literal_test1() {
+    use std::net::Ipv4Addr;
+    let _ = Ipv4Addr::new(127, 0, 0, 1);
+    //~^ ip_constant
+    let _ = Ipv4Addr::new(255, 255, 255, 255);
+    //~^ ip_constant
+    let _ = Ipv4Addr::new(0, 0, 0, 0);
+    //~^ ip_constant
+
+    use std::net::Ipv6Addr;
+    let _ = Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 1);
+    //~^ ip_constant
+    let _ = Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 0);
+    //~^ ip_constant
+}
+
+fn literal_test2() {
+    use std::net;
+    let _ = net::Ipv4Addr::new(127, 0, 0, 1);
+    //~^ ip_constant
+    let _ = net::Ipv4Addr::new(255, 255, 255, 255);
+    //~^ ip_constant
+    let _ = net::Ipv4Addr::new(0, 0, 0, 0);
+    //~^ ip_constant
+
+    let _ = net::Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 1);
+    //~^ ip_constant
+    let _ = net::Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 0);
+    //~^ ip_constant
+}
+
+fn literal_test3() {
+    let _ = std::net::Ipv4Addr::new(127, 0, 0, 1);
+    //~^ ip_constant
+    let _ = std::net::Ipv4Addr::new(255, 255, 255, 255);
+    //~^ ip_constant
+    let _ = std::net::Ipv4Addr::new(0, 0, 0, 0);
+    //~^ ip_constant
+
+    let _ = std::net::Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 1);
+    //~^ ip_constant
+    let _ = std::net::Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 0);
+    //~^ ip_constant
+}
+
+const CONST_U8_0: u8 = 0;
+const CONST_U8_1: u8 = 1;
+const CONST_U8_127: u8 = 127;
+const CONST_U8_255: u8 = 255;
+
+const CONST_U16_0: u16 = 0;
+const CONST_U16_1: u16 = 1;
+
+fn const_test1() {
+    use std::net::Ipv4Addr;
+    let _ = Ipv4Addr::new(CONST_U8_127, CONST_U8_0, CONST_U8_0, CONST_U8_1);
+    //~^ ip_constant
+    let _ = Ipv4Addr::new(CONST_U8_255, CONST_U8_255, CONST_U8_255, CONST_U8_255);
+    //~^ ip_constant
+    let _ = Ipv4Addr::new(CONST_U8_0, CONST_U8_0, CONST_U8_0, CONST_U8_0);
+    //~^ ip_constant
+
+    use std::net::Ipv6Addr;
+    let _ = Ipv6Addr::new(
+        //~^ ip_constant
+        CONST_U16_0,
+        CONST_U16_0,
+        CONST_U16_0,
+        CONST_U16_0,
+        CONST_U16_0,
+        CONST_U16_0,
+        CONST_U16_0,
+        CONST_U16_1,
+    );
+
+    let _ = Ipv6Addr::new(
+        //~^ ip_constant
+        CONST_U16_0,
+        CONST_U16_0,
+        CONST_U16_0,
+        CONST_U16_0,
+        CONST_U16_0,
+        CONST_U16_0,
+        CONST_U16_0,
+        CONST_U16_0,
+    );
+}
+
+fn const_test2() {
+    use std::net::Ipv4Addr;
+    let _ = Ipv4Addr::new(126 + 1, 0, 0, 1);
+    //~^ ip_constant
+    let _ = Ipv4Addr::new(254 + CONST_U8_1, 255, { 255 - CONST_U8_0 }, CONST_U8_255);
+    //~^ ip_constant
+    let _ = Ipv4Addr::new(0, CONST_U8_255 - 255, 0, { 1 + 0 - 1 });
+    //~^ ip_constant
+
+    use std::net::Ipv6Addr;
+    let _ = Ipv6Addr::new(0 + CONST_U16_0, 0, 0, 0, 0, 0, 0, 1);
+    //~^ ip_constant
+    let _ = Ipv6Addr::new(0 + 0, 0, 0, 0, 0, { 2 - 1 - CONST_U16_1 }, 0, 1);
+    //~^ ip_constant
+}
+
+macro_rules! ipv4_new {
+    ($a:expr, $b:expr, $c:expr, $d:expr) => {
+        std::net::Ipv4Addr::new($a, $b, $c, $d)
+    };
+}
+
+fn macro_test() {
+    let _ = ipv4_new!(127, 0, 0, 1);
+    // no lint
+    let _ = ipv4_new!(255, 255, 255, 255);
+    // no lint
+    let _ = ipv4_new!(0, 0, 0, 0);
+    // no lint
+}
+
+fn main() {
+    // UI Test
+}
diff --git a/src/tools/clippy/tests/ui/ip_constant.stderr b/src/tools/clippy/tests/ui/ip_constant.stderr
new file mode 100644
index 00000000000..3e984c6cb3b
--- /dev/null
+++ b/src/tools/clippy/tests/ui/ip_constant.stderr
@@ -0,0 +1,338 @@
+error: hand-coded well-known IP address
+  --> tests/ui/ip_constant.rs:8:13
+   |
+LL |     let _ = Ipv4Addr::new(127, 0, 0, 1);
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: `-D clippy::ip-constant` implied by `-D warnings`
+   = help: to override `-D warnings` add `#[allow(clippy::ip_constant)]`
+help: use
+   |
+LL -     let _ = Ipv4Addr::new(127, 0, 0, 1);
+LL +     let _ = Ipv4Addr::LOCALHOST;
+   |
+
+error: hand-coded well-known IP address
+  --> tests/ui/ip_constant.rs:10:13
+   |
+LL |     let _ = Ipv4Addr::new(255, 255, 255, 255);
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: use
+   |
+LL -     let _ = Ipv4Addr::new(255, 255, 255, 255);
+LL +     let _ = Ipv4Addr::BROADCAST;
+   |
+
+error: hand-coded well-known IP address
+  --> tests/ui/ip_constant.rs:12:13
+   |
+LL |     let _ = Ipv4Addr::new(0, 0, 0, 0);
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: use
+   |
+LL -     let _ = Ipv4Addr::new(0, 0, 0, 0);
+LL +     let _ = Ipv4Addr::UNSPECIFIED;
+   |
+
+error: hand-coded well-known IP address
+  --> tests/ui/ip_constant.rs:16:13
+   |
+LL |     let _ = Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 1);
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: use
+   |
+LL -     let _ = Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 1);
+LL +     let _ = Ipv6Addr::LOCALHOST;
+   |
+
+error: hand-coded well-known IP address
+  --> tests/ui/ip_constant.rs:18:13
+   |
+LL |     let _ = Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 0);
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: use
+   |
+LL -     let _ = Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 0);
+LL +     let _ = Ipv6Addr::UNSPECIFIED;
+   |
+
+error: hand-coded well-known IP address
+  --> tests/ui/ip_constant.rs:24:13
+   |
+LL |     let _ = net::Ipv4Addr::new(127, 0, 0, 1);
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: use
+   |
+LL -     let _ = net::Ipv4Addr::new(127, 0, 0, 1);
+LL +     let _ = net::Ipv4Addr::LOCALHOST;
+   |
+
+error: hand-coded well-known IP address
+  --> tests/ui/ip_constant.rs:26:13
+   |
+LL |     let _ = net::Ipv4Addr::new(255, 255, 255, 255);
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: use
+   |
+LL -     let _ = net::Ipv4Addr::new(255, 255, 255, 255);
+LL +     let _ = net::Ipv4Addr::BROADCAST;
+   |
+
+error: hand-coded well-known IP address
+  --> tests/ui/ip_constant.rs:28:13
+   |
+LL |     let _ = net::Ipv4Addr::new(0, 0, 0, 0);
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: use
+   |
+LL -     let _ = net::Ipv4Addr::new(0, 0, 0, 0);
+LL +     let _ = net::Ipv4Addr::UNSPECIFIED;
+   |
+
+error: hand-coded well-known IP address
+  --> tests/ui/ip_constant.rs:31:13
+   |
+LL |     let _ = net::Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 1);
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: use
+   |
+LL -     let _ = net::Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 1);
+LL +     let _ = net::Ipv6Addr::LOCALHOST;
+   |
+
+error: hand-coded well-known IP address
+  --> tests/ui/ip_constant.rs:33:13
+   |
+LL |     let _ = net::Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 0);
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: use
+   |
+LL -     let _ = net::Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 0);
+LL +     let _ = net::Ipv6Addr::UNSPECIFIED;
+   |
+
+error: hand-coded well-known IP address
+  --> tests/ui/ip_constant.rs:38:13
+   |
+LL |     let _ = std::net::Ipv4Addr::new(127, 0, 0, 1);
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: use
+   |
+LL -     let _ = std::net::Ipv4Addr::new(127, 0, 0, 1);
+LL +     let _ = std::net::Ipv4Addr::LOCALHOST;
+   |
+
+error: hand-coded well-known IP address
+  --> tests/ui/ip_constant.rs:40:13
+   |
+LL |     let _ = std::net::Ipv4Addr::new(255, 255, 255, 255);
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: use
+   |
+LL -     let _ = std::net::Ipv4Addr::new(255, 255, 255, 255);
+LL +     let _ = std::net::Ipv4Addr::BROADCAST;
+   |
+
+error: hand-coded well-known IP address
+  --> tests/ui/ip_constant.rs:42:13
+   |
+LL |     let _ = std::net::Ipv4Addr::new(0, 0, 0, 0);
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: use
+   |
+LL -     let _ = std::net::Ipv4Addr::new(0, 0, 0, 0);
+LL +     let _ = std::net::Ipv4Addr::UNSPECIFIED;
+   |
+
+error: hand-coded well-known IP address
+  --> tests/ui/ip_constant.rs:45:13
+   |
+LL |     let _ = std::net::Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 1);
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: use
+   |
+LL -     let _ = std::net::Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 1);
+LL +     let _ = std::net::Ipv6Addr::LOCALHOST;
+   |
+
+error: hand-coded well-known IP address
+  --> tests/ui/ip_constant.rs:47:13
+   |
+LL |     let _ = std::net::Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 0);
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: use
+   |
+LL -     let _ = std::net::Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 0);
+LL +     let _ = std::net::Ipv6Addr::UNSPECIFIED;
+   |
+
+error: hand-coded well-known IP address
+  --> tests/ui/ip_constant.rs:61:13
+   |
+LL |     let _ = Ipv4Addr::new(CONST_U8_127, CONST_U8_0, CONST_U8_0, CONST_U8_1);
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: use
+   |
+LL -     let _ = Ipv4Addr::new(CONST_U8_127, CONST_U8_0, CONST_U8_0, CONST_U8_1);
+LL +     let _ = Ipv4Addr::LOCALHOST;
+   |
+
+error: hand-coded well-known IP address
+  --> tests/ui/ip_constant.rs:63:13
+   |
+LL |     let _ = Ipv4Addr::new(CONST_U8_255, CONST_U8_255, CONST_U8_255, CONST_U8_255);
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: use
+   |
+LL -     let _ = Ipv4Addr::new(CONST_U8_255, CONST_U8_255, CONST_U8_255, CONST_U8_255);
+LL +     let _ = Ipv4Addr::BROADCAST;
+   |
+
+error: hand-coded well-known IP address
+  --> tests/ui/ip_constant.rs:65:13
+   |
+LL |     let _ = Ipv4Addr::new(CONST_U8_0, CONST_U8_0, CONST_U8_0, CONST_U8_0);
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: use
+   |
+LL -     let _ = Ipv4Addr::new(CONST_U8_0, CONST_U8_0, CONST_U8_0, CONST_U8_0);
+LL +     let _ = Ipv4Addr::UNSPECIFIED;
+   |
+
+error: hand-coded well-known IP address
+  --> tests/ui/ip_constant.rs:69:13
+   |
+LL |       let _ = Ipv6Addr::new(
+   |  _____________^
+LL | |
+LL | |         CONST_U16_0,
+LL | |         CONST_U16_0,
+...  |
+LL | |         CONST_U16_1,
+LL | |     );
+   | |_____^
+   |
+help: use
+   |
+LL -     let _ = Ipv6Addr::new(
+LL -
+LL -         CONST_U16_0,
+LL -         CONST_U16_0,
+LL -         CONST_U16_0,
+LL -         CONST_U16_0,
+LL -         CONST_U16_0,
+LL -         CONST_U16_0,
+LL -         CONST_U16_0,
+LL -         CONST_U16_1,
+LL -     );
+LL +     let _ = Ipv6Addr::LOCALHOST;
+   |
+
+error: hand-coded well-known IP address
+  --> tests/ui/ip_constant.rs:81:13
+   |
+LL |       let _ = Ipv6Addr::new(
+   |  _____________^
+LL | |
+LL | |         CONST_U16_0,
+LL | |         CONST_U16_0,
+...  |
+LL | |         CONST_U16_0,
+LL | |     );
+   | |_____^
+   |
+help: use
+   |
+LL -     let _ = Ipv6Addr::new(
+LL -
+LL -         CONST_U16_0,
+LL -         CONST_U16_0,
+LL -         CONST_U16_0,
+LL -         CONST_U16_0,
+LL -         CONST_U16_0,
+LL -         CONST_U16_0,
+LL -         CONST_U16_0,
+LL -         CONST_U16_0,
+LL -     );
+LL +     let _ = Ipv6Addr::UNSPECIFIED;
+   |
+
+error: hand-coded well-known IP address
+  --> tests/ui/ip_constant.rs:96:13
+   |
+LL |     let _ = Ipv4Addr::new(126 + 1, 0, 0, 1);
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: use
+   |
+LL -     let _ = Ipv4Addr::new(126 + 1, 0, 0, 1);
+LL +     let _ = Ipv4Addr::LOCALHOST;
+   |
+
+error: hand-coded well-known IP address
+  --> tests/ui/ip_constant.rs:98:13
+   |
+LL |     let _ = Ipv4Addr::new(254 + CONST_U8_1, 255, { 255 - CONST_U8_0 }, CONST_U8_255);
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: use
+   |
+LL -     let _ = Ipv4Addr::new(254 + CONST_U8_1, 255, { 255 - CONST_U8_0 }, CONST_U8_255);
+LL +     let _ = Ipv4Addr::BROADCAST;
+   |
+
+error: hand-coded well-known IP address
+  --> tests/ui/ip_constant.rs:100:13
+   |
+LL |     let _ = Ipv4Addr::new(0, CONST_U8_255 - 255, 0, { 1 + 0 - 1 });
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: use
+   |
+LL -     let _ = Ipv4Addr::new(0, CONST_U8_255 - 255, 0, { 1 + 0 - 1 });
+LL +     let _ = Ipv4Addr::UNSPECIFIED;
+   |
+
+error: hand-coded well-known IP address
+  --> tests/ui/ip_constant.rs:104:13
+   |
+LL |     let _ = Ipv6Addr::new(0 + CONST_U16_0, 0, 0, 0, 0, 0, 0, 1);
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: use
+   |
+LL -     let _ = Ipv6Addr::new(0 + CONST_U16_0, 0, 0, 0, 0, 0, 0, 1);
+LL +     let _ = Ipv6Addr::LOCALHOST;
+   |
+
+error: hand-coded well-known IP address
+  --> tests/ui/ip_constant.rs:106:13
+   |
+LL |     let _ = Ipv6Addr::new(0 + 0, 0, 0, 0, 0, { 2 - 1 - CONST_U16_1 }, 0, 1);
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: use
+   |
+LL -     let _ = Ipv6Addr::new(0 + 0, 0, 0, 0, 0, { 2 - 1 - CONST_U16_1 }, 0, 1);
+LL +     let _ = Ipv6Addr::LOCALHOST;
+   |
+
+error: aborting due to 25 previous errors
+
diff --git a/src/tools/clippy/tests/ui/ip_constant_from_external.rs b/src/tools/clippy/tests/ui/ip_constant_from_external.rs
new file mode 100644
index 00000000000..7fd27022f12
--- /dev/null
+++ b/src/tools/clippy/tests/ui/ip_constant_from_external.rs
@@ -0,0 +1,12 @@
+//@error-in-other-file: hand-coded well-known IP address
+//@no-rustfix
+#![warn(clippy::ip_constant)]
+
+fn external_constant_test() {
+    let _ = include!("localhost.txt");
+    // lint in external file `localhost.txt`
+}
+
+fn main() {
+    external_constant_test();
+}
diff --git a/src/tools/clippy/tests/ui/ip_constant_from_external.stderr b/src/tools/clippy/tests/ui/ip_constant_from_external.stderr
new file mode 100644
index 00000000000..99dd827d41f
--- /dev/null
+++ b/src/tools/clippy/tests/ui/ip_constant_from_external.stderr
@@ -0,0 +1,16 @@
+error: hand-coded well-known IP address
+  --> tests/ui/localhost.txt:1:1
+   |
+LL | std::net::Ipv4Addr::new(127, 0, 0, 1)
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: `-D clippy::ip-constant` implied by `-D warnings`
+   = help: to override `-D warnings` add `#[allow(clippy::ip_constant)]`
+help: use
+   |
+LL - std::net::Ipv4Addr::new(127, 0, 0, 1)
+LL + std::net::Ipv4Addr::LOCALHOST
+   |
+
+error: aborting due to 1 previous error
+
diff --git a/src/tools/clippy/tests/ui/large_stack_frames.rs b/src/tools/clippy/tests/ui/large_stack_frames.rs
index 3ed124f69ef..132f1450b6d 100644
--- a/src/tools/clippy/tests/ui/large_stack_frames.rs
+++ b/src/tools/clippy/tests/ui/large_stack_frames.rs
@@ -1,8 +1,7 @@
 //@ normalize-stderr-test: "\b10000(08|16|32)\b" -> "100$$PTR"
 //@ normalize-stderr-test: "\b2500(060|120)\b" -> "250$$PTR"
-#![allow(unused, incomplete_features)]
+#![allow(unused)]
 #![warn(clippy::large_stack_frames)]
-#![feature(unsized_locals)]
 
 use std::hint::black_box;
 
@@ -11,11 +10,6 @@ fn generic<T: Default>() {
     black_box(&x);
 }
 
-fn unsized_local() {
-    let x: dyn std::fmt::Display = *(Box::new(1) as Box<dyn std::fmt::Display>);
-    black_box(&x);
-}
-
 struct ArrayDefault<const N: usize>([u8; N]);
 
 impl<const N: usize> Default for ArrayDefault<N> {
diff --git a/src/tools/clippy/tests/ui/large_stack_frames.stderr b/src/tools/clippy/tests/ui/large_stack_frames.stderr
index 0ff49e9f5b3..79482e65c3e 100644
--- a/src/tools/clippy/tests/ui/large_stack_frames.stderr
+++ b/src/tools/clippy/tests/ui/large_stack_frames.stderr
@@ -1,5 +1,5 @@
 error: this function may allocate 250$PTR bytes on the stack
-  --> tests/ui/large_stack_frames.rs:27:4
+  --> tests/ui/large_stack_frames.rs:21:4
    |
 LL | fn many_small_arrays() {
    |    ^^^^^^^^^^^^^^^^^
@@ -13,7 +13,7 @@ LL |     let x5 = [0u8; 500_000];
    = help: to override `-D warnings` add `#[allow(clippy::large_stack_frames)]`
 
 error: this function may allocate 1000000 bytes on the stack
-  --> tests/ui/large_stack_frames.rs:38:4
+  --> tests/ui/large_stack_frames.rs:32:4
    |
 LL | fn large_return_value() -> ArrayDefault<1_000_000> {
    |    ^^^^^^^^^^^^^^^^^^      ----------------------- this is the largest part, at 1000000 bytes for type `ArrayDefault<1000000>`
@@ -21,7 +21,7 @@ LL | fn large_return_value() -> ArrayDefault<1_000_000> {
    = note: 1000000 bytes is larger than Clippy's configured `stack-size-threshold` of 512000
 
 error: this function may allocate 100$PTR bytes on the stack
-  --> tests/ui/large_stack_frames.rs:44:4
+  --> tests/ui/large_stack_frames.rs:38:4
    |
 LL | fn large_fn_arg(x: ArrayDefault<1_000_000>) {
    |    ^^^^^^^^^^^^ - `x` is the largest part, at 1000000 bytes for type `ArrayDefault<1000000>`
@@ -29,7 +29,7 @@ LL | fn large_fn_arg(x: ArrayDefault<1_000_000>) {
    = note: 100$PTR bytes is larger than Clippy's configured `stack-size-threshold` of 512000
 
 error: this function may allocate 100$PTR bytes on the stack
-  --> tests/ui/large_stack_frames.rs:51:13
+  --> tests/ui/large_stack_frames.rs:45:13
    |
 LL |     let f = || black_box(&[0u8; 1_000_000]);
    |             ^^^^^^^^^^^^^^----------------^
diff --git a/src/tools/clippy/tests/ui/localhost.txt b/src/tools/clippy/tests/ui/localhost.txt
new file mode 100644
index 00000000000..4502ec2b234
--- /dev/null
+++ b/src/tools/clippy/tests/ui/localhost.txt
@@ -0,0 +1 @@
+std::net::Ipv4Addr::new(127, 0, 0, 1)
\ No newline at end of file
diff --git a/src/tools/clippy/tests/ui/manual_flatten.fixed b/src/tools/clippy/tests/ui/manual_flatten.fixed
new file mode 100644
index 00000000000..cc1fbd25765
--- /dev/null
+++ b/src/tools/clippy/tests/ui/manual_flatten.fixed
@@ -0,0 +1,148 @@
+#![warn(clippy::manual_flatten)]
+#![allow(clippy::useless_vec, clippy::uninlined_format_args)]
+
+fn main() {
+    // Test for loop over implicitly adjusted `Iterator` with `if let` expression
+    let x = vec![Some(1), Some(2), Some(3)];
+    for y in x.into_iter().flatten() {
+        println!("{}", y);
+    }
+
+    // Test for loop over implicitly adjusted `Iterator` with `if let` statement
+    let y: Vec<Result<i32, i32>> = vec![];
+    for n in y.clone().into_iter().flatten() {
+        println!("{}", n);
+    }
+
+    // Test for loop over by reference
+    for n in y.iter().flatten() {
+        println!("{}", n);
+    }
+
+    // Test for loop over an implicit reference
+    let z = &y;
+    for n in z.iter().flatten() {
+        println!("{}", n);
+    }
+
+    // Test for loop over `Iterator` with `if let` expression
+    let z = vec![Some(1), Some(2), Some(3)];
+    let z = z.iter();
+    for m in z.flatten() {
+        println!("{}", m);
+    }
+
+    // Using the `None` variant should not trigger the lint
+    // Note: for an autofixable suggestion, the binding in the for loop has to take the
+    // name of the binding in the `if let`
+    let z = vec![Some(1), Some(2), Some(3)];
+    for n in z {
+        if n.is_none() {
+            println!("Nada.");
+        }
+    }
+
+    // Using the `Err` variant should not trigger the lint
+    for n in y.clone() {
+        if let Err(e) = n {
+            println!("Oops: {}!", e);
+        }
+    }
+
+    // Having an else clause should not trigger the lint
+    for n in y.clone() {
+        if let Ok(n) = n {
+            println!("{}", n);
+        } else {
+            println!("Oops!");
+        }
+    }
+
+    let vec_of_ref = vec![&Some(1)];
+    for n in vec_of_ref.iter().copied().flatten() {
+        println!("{:?}", n);
+    }
+
+    let vec_of_ref = &vec_of_ref;
+    for n in vec_of_ref.iter().copied().flatten() {
+        println!("{:?}", n);
+    }
+
+    let slice_of_ref = &[&Some(1)];
+    for n in slice_of_ref.iter().copied().flatten() {
+        println!("{:?}", n);
+    }
+
+    struct Test {
+        a: usize,
+    }
+
+    let mut vec_of_struct = [Some(Test { a: 1 }), None];
+
+    // Usage of `if let` expression should not trigger lint
+    for n in vec_of_struct.iter_mut() {
+        if let Some(z) = n {
+            *n = None;
+        }
+    }
+
+    // Using manual flatten should not trigger the lint
+    for n in vec![Some(1), Some(2), Some(3)].iter().flatten() {
+        println!("{}", n);
+    }
+
+    // Using nested `Some` pattern should not trigger the lint
+    for n in vec![Some((1, Some(2)))] {
+        if let Some((_, Some(n))) = n {
+            println!("{}", n);
+        }
+    }
+
+    macro_rules! inner {
+        ($id:ident / $new:pat => $action:expr) => {
+            if let Some($new) = $id {
+                $action;
+            }
+        };
+    }
+
+    // Usage of `if let` expression with macro should not trigger lint
+    for ab in [Some((1, 2)), Some((3, 4))] {
+        inner!(ab / (c, d) => println!("{c}-{d}"));
+    }
+
+    macro_rules! args {
+        ($($arg:expr),*) => {
+            vec![$(Some($arg)),*]
+        };
+    }
+
+    // Usage of `if let` expression with macro should not trigger lint
+    for n in args!(1, 2, 3) {
+        if let Some(n) = n {
+            println!("{:?}", n);
+        }
+    }
+
+    // This should trigger the lint, but the applicability is `MaybeIncorrect`
+    let z = vec![Some(1), Some(2), Some(3)];
+    for n in z.into_iter().flatten() {
+        println!("{:?}", n);
+    }
+
+    run_unformatted_tests();
+}
+
+#[rustfmt::skip]
+fn run_unformatted_tests() {
+    // Skip rustfmt here on purpose so the suggestion does not fit in one line
+    for n in vec![
+    //~^ manual_flatten
+
+        Some(1),
+        Some(2),
+        Some(3)
+    ].iter().flatten() {
+        println!("{:?}", n);
+    }
+}
diff --git a/src/tools/clippy/tests/ui/manual_flatten.rs b/src/tools/clippy/tests/ui/manual_flatten.rs
index f1a0053ef38..53b4ac7d3b6 100644
--- a/src/tools/clippy/tests/ui/manual_flatten.rs
+++ b/src/tools/clippy/tests/ui/manual_flatten.rs
@@ -1,6 +1,6 @@
 #![warn(clippy::manual_flatten)]
 #![allow(clippy::useless_vec, clippy::uninlined_format_args)]
-//@no-rustfix
+
 fn main() {
     // Test for loop over implicitly adjusted `Iterator` with `if let` expression
     let x = vec![Some(1), Some(2), Some(3)];
@@ -130,6 +130,43 @@ fn main() {
         }
     }
 
+    macro_rules! inner {
+        ($id:ident / $new:pat => $action:expr) => {
+            if let Some($new) = $id {
+                $action;
+            }
+        };
+    }
+
+    // Usage of `if let` expression with macro should not trigger lint
+    for ab in [Some((1, 2)), Some((3, 4))] {
+        inner!(ab / (c, d) => println!("{c}-{d}"));
+    }
+
+    macro_rules! args {
+        ($($arg:expr),*) => {
+            vec![$(Some($arg)),*]
+        };
+    }
+
+    // Usage of `if let` expression with macro should not trigger lint
+    for n in args!(1, 2, 3) {
+        if let Some(n) = n {
+            println!("{:?}", n);
+        }
+    }
+
+    // This should trigger the lint, but the applicability is `MaybeIncorrect`
+    let z = vec![Some(1), Some(2), Some(3)];
+    for n in z {
+        //~^ manual_flatten
+
+        if let Some(n) = n {
+            println!("{:?}", n);
+        }
+        // foo
+    }
+
     run_unformatted_tests();
 }
 
diff --git a/src/tools/clippy/tests/ui/manual_flatten.stderr b/src/tools/clippy/tests/ui/manual_flatten.stderr
index 9a846fe17f3..eb39ee42071 100644
--- a/src/tools/clippy/tests/ui/manual_flatten.stderr
+++ b/src/tools/clippy/tests/ui/manual_flatten.stderr
@@ -1,10 +1,7 @@
 error: unnecessary `if let` since only the `Some` variant of the iterator element is used
   --> tests/ui/manual_flatten.rs:7:5
    |
-LL |       for n in x {
-   |       ^        - help: try: `x.into_iter().flatten()`
-   |  _____|
-   | |
+LL | /     for n in x {
 LL | |
 LL | |
 LL | |         if let Some(y) = n {
@@ -12,7 +9,7 @@ LL | |         if let Some(y) = n {
 LL | |     }
    | |_____^
    |
-help: ...and remove the `if let` statement in the for loop
+help: try `.flatten()` and remove the `if let` statement in the for loop
   --> tests/ui/manual_flatten.rs:10:9
    |
 LL | /         if let Some(y) = n {
@@ -21,14 +18,17 @@ LL | |         }
    | |_________^
    = note: `-D clippy::manual-flatten` implied by `-D warnings`
    = help: to override `-D warnings` add `#[allow(clippy::manual_flatten)]`
+help: try
+   |
+LL ~     for y in x.into_iter().flatten() {
+LL +         println!("{}", y);
+LL +     }
+   |
 
 error: unnecessary `if let` since only the `Ok` variant of the iterator element is used
   --> tests/ui/manual_flatten.rs:17:5
    |
-LL |       for n in y.clone() {
-   |       ^        --------- help: try: `y.clone().into_iter().flatten()`
-   |  _____|
-   | |
+LL | /     for n in y.clone() {
 LL | |
 LL | |
 LL | |         if let Ok(n) = n {
@@ -37,21 +37,24 @@ LL | |         };
 LL | |     }
    | |_____^
    |
-help: ...and remove the `if let` statement in the for loop
+help: try `.flatten()` and remove the `if let` statement in the for loop
   --> tests/ui/manual_flatten.rs:20:9
    |
 LL | /         if let Ok(n) = n {
 LL | |             println!("{}", n);
 LL | |         };
    | |_________^
+help: try
+   |
+LL ~     for n in y.clone().into_iter().flatten() {
+LL +         println!("{}", n);
+LL +     }
+   |
 
 error: unnecessary `if let` since only the `Ok` variant of the iterator element is used
   --> tests/ui/manual_flatten.rs:26:5
    |
-LL |       for n in &y {
-   |       ^        -- help: try: `y.iter().flatten()`
-   |  _____|
-   | |
+LL | /     for n in &y {
 LL | |
 LL | |
 LL | |         if let Ok(n) = n {
@@ -59,21 +62,24 @@ LL | |         if let Ok(n) = n {
 LL | |     }
    | |_____^
    |
-help: ...and remove the `if let` statement in the for loop
+help: try `.flatten()` and remove the `if let` statement in the for loop
   --> tests/ui/manual_flatten.rs:29:9
    |
 LL | /         if let Ok(n) = n {
 LL | |             println!("{}", n);
 LL | |         }
    | |_________^
+help: try
+   |
+LL ~     for n in y.iter().flatten() {
+LL +         println!("{}", n);
+LL +     }
+   |
 
 error: unnecessary `if let` since only the `Ok` variant of the iterator element is used
   --> tests/ui/manual_flatten.rs:36:5
    |
-LL |       for n in z {
-   |       ^        - help: try: `z.iter().flatten()`
-   |  _____|
-   | |
+LL | /     for n in z {
 LL | |
 LL | |
 LL | |         if let Ok(n) = n {
@@ -81,21 +87,24 @@ LL | |         if let Ok(n) = n {
 LL | |     }
    | |_____^
    |
-help: ...and remove the `if let` statement in the for loop
+help: try `.flatten()` and remove the `if let` statement in the for loop
   --> tests/ui/manual_flatten.rs:39:9
    |
 LL | /         if let Ok(n) = n {
 LL | |             println!("{}", n);
 LL | |         }
    | |_________^
+help: try
+   |
+LL ~     for n in z.iter().flatten() {
+LL +         println!("{}", n);
+LL +     }
+   |
 
 error: unnecessary `if let` since only the `Some` variant of the iterator element is used
   --> tests/ui/manual_flatten.rs:47:5
    |
-LL |       for n in z {
-   |       ^        - help: try: `z.flatten()`
-   |  _____|
-   | |
+LL | /     for n in z {
 LL | |
 LL | |
 LL | |         if let Some(m) = n {
@@ -103,21 +112,24 @@ LL | |         if let Some(m) = n {
 LL | |     }
    | |_____^
    |
-help: ...and remove the `if let` statement in the for loop
+help: try `.flatten()` and remove the `if let` statement in the for loop
   --> tests/ui/manual_flatten.rs:50:9
    |
 LL | /         if let Some(m) = n {
 LL | |             println!("{}", m);
 LL | |         }
    | |_________^
+help: try
+   |
+LL ~     for m in z.flatten() {
+LL +         println!("{}", m);
+LL +     }
+   |
 
 error: unnecessary `if let` since only the `Some` variant of the iterator element is used
   --> tests/ui/manual_flatten.rs:82:5
    |
-LL |       for n in &vec_of_ref {
-   |       ^        ----------- help: try: `vec_of_ref.iter().copied().flatten()`
-   |  _____|
-   | |
+LL | /     for n in &vec_of_ref {
 LL | |
 LL | |
 LL | |         if let Some(n) = n {
@@ -125,21 +137,24 @@ LL | |         if let Some(n) = n {
 LL | |     }
    | |_____^
    |
-help: ...and remove the `if let` statement in the for loop
+help: try `.flatten()` and remove the `if let` statement in the for loop
   --> tests/ui/manual_flatten.rs:85:9
    |
 LL | /         if let Some(n) = n {
 LL | |             println!("{:?}", n);
 LL | |         }
    | |_________^
+help: try
+   |
+LL ~     for n in vec_of_ref.iter().copied().flatten() {
+LL +         println!("{:?}", n);
+LL +     }
+   |
 
 error: unnecessary `if let` since only the `Some` variant of the iterator element is used
   --> tests/ui/manual_flatten.rs:91:5
    |
-LL |       for n in vec_of_ref {
-   |       ^        ---------- help: try: `vec_of_ref.iter().copied().flatten()`
-   |  _____|
-   | |
+LL | /     for n in vec_of_ref {
 LL | |
 LL | |
 LL | |         if let Some(n) = n {
@@ -147,21 +162,24 @@ LL | |         if let Some(n) = n {
 LL | |     }
    | |_____^
    |
-help: ...and remove the `if let` statement in the for loop
+help: try `.flatten()` and remove the `if let` statement in the for loop
   --> tests/ui/manual_flatten.rs:94:9
    |
 LL | /         if let Some(n) = n {
 LL | |             println!("{:?}", n);
 LL | |         }
    | |_________^
+help: try
+   |
+LL ~     for n in vec_of_ref.iter().copied().flatten() {
+LL +         println!("{:?}", n);
+LL +     }
+   |
 
 error: unnecessary `if let` since only the `Some` variant of the iterator element is used
   --> tests/ui/manual_flatten.rs:100:5
    |
-LL |       for n in slice_of_ref {
-   |       ^        ------------ help: try: `slice_of_ref.iter().copied().flatten()`
-   |  _____|
-   | |
+LL | /     for n in slice_of_ref {
 LL | |
 LL | |
 LL | |         if let Some(n) = n {
@@ -169,16 +187,47 @@ LL | |         if let Some(n) = n {
 LL | |     }
    | |_____^
    |
-help: ...and remove the `if let` statement in the for loop
+help: try `.flatten()` and remove the `if let` statement in the for loop
   --> tests/ui/manual_flatten.rs:103:9
    |
 LL | /         if let Some(n) = n {
 LL | |             println!("{:?}", n);
 LL | |         }
    | |_________^
+help: try
+   |
+LL ~     for n in slice_of_ref.iter().copied().flatten() {
+LL +         println!("{:?}", n);
+LL +     }
+   |
+
+error: unnecessary `if let` since only the `Some` variant of the iterator element is used
+  --> tests/ui/manual_flatten.rs:161:5
+   |
+LL | /     for n in z {
+LL | |
+LL | |
+LL | |         if let Some(n) = n {
+...  |
+LL | |     }
+   | |_____^
+   |
+help: try `.flatten()` and remove the `if let` statement in the for loop
+  --> tests/ui/manual_flatten.rs:164:9
+   |
+LL | /         if let Some(n) = n {
+LL | |             println!("{:?}", n);
+LL | |         }
+   | |_________^
+help: try
+   |
+LL ~     for n in z.into_iter().flatten() {
+LL +         println!("{:?}", n);
+LL +     }
+   |
 
 error: unnecessary `if let` since only the `Some` variant of the iterator element is used
-  --> tests/ui/manual_flatten.rs:139:5
+  --> tests/ui/manual_flatten.rs:176:5
    |
 LL | /     for n in vec![
 LL | |
@@ -188,8 +237,8 @@ LL | |         Some(1),
 LL | |     }
    | |_____^
    |
-help: remove the `if let` statement in the for loop and then...
-  --> tests/ui/manual_flatten.rs:146:9
+help: try `.flatten()` and remove the `if let` statement in the for loop
+  --> tests/ui/manual_flatten.rs:183:9
    |
 LL | /         if let Some(n) = n {
 LL | |             println!("{:?}", n);
@@ -201,7 +250,9 @@ LL |     for n in vec![
 ...
 LL |         Some(3)
 LL ~     ].iter().flatten() {
+LL +         println!("{:?}", n);
+LL +     }
    |
 
-error: aborting due to 9 previous errors
+error: aborting due to 10 previous errors
 
diff --git a/src/tools/clippy/tests/ui/manual_swap_auto_fix.fixed b/src/tools/clippy/tests/ui/manual_swap_auto_fix.fixed
index 28466ff3f9b..6cd81bafce8 100644
--- a/src/tools/clippy/tests/ui/manual_swap_auto_fix.fixed
+++ b/src/tools/clippy/tests/ui/manual_swap_auto_fix.fixed
@@ -55,3 +55,14 @@ fn swap8() {
     let i2 = 1;
     v.swap(i1 + i2, i2);
 }
+
+fn issue_14931() {
+    let mut v = [1, 2, 3, 4];
+
+    let mut i1 = 0;
+    for i2 in 0..4 {
+        v.swap(i1, i2);
+
+        i1 += 2;
+    }
+}
diff --git a/src/tools/clippy/tests/ui/manual_swap_auto_fix.rs b/src/tools/clippy/tests/ui/manual_swap_auto_fix.rs
index c9880e651cd..19dabfd833f 100644
--- a/src/tools/clippy/tests/ui/manual_swap_auto_fix.rs
+++ b/src/tools/clippy/tests/ui/manual_swap_auto_fix.rs
@@ -78,3 +78,17 @@ fn swap8() {
     v[i1 + i2] = v[i2];
     v[i2] = tmp;
 }
+
+fn issue_14931() {
+    let mut v = [1, 2, 3, 4];
+
+    let mut i1 = 0;
+    for i2 in 0..4 {
+        let tmp = v[i1];
+        //~^ manual_swap
+        v[i1] = v[i2];
+        v[i2] = tmp;
+
+        i1 += 2;
+    }
+}
diff --git a/src/tools/clippy/tests/ui/manual_swap_auto_fix.stderr b/src/tools/clippy/tests/ui/manual_swap_auto_fix.stderr
index 7ab898fcc72..a0bb32233e2 100644
--- a/src/tools/clippy/tests/ui/manual_swap_auto_fix.stderr
+++ b/src/tools/clippy/tests/ui/manual_swap_auto_fix.stderr
@@ -92,5 +92,14 @@ LL | |     v[i1 + i2] = v[i2];
 LL | |     v[i2] = tmp;
    | |________________^ help: try: `v.swap(i1 + i2, i2);`
 
-error: aborting due to 8 previous errors
+error: this looks like you are swapping elements of `v` manually
+  --> tests/ui/manual_swap_auto_fix.rs:87:9
+   |
+LL | /         let tmp = v[i1];
+LL | |
+LL | |         v[i1] = v[i2];
+LL | |         v[i2] = tmp;
+   | |____________________^ help: try: `v.swap(i1, i2);`
+
+error: aborting due to 9 previous errors
 
diff --git a/src/tools/clippy/tests/ui/match_single_binding.fixed b/src/tools/clippy/tests/ui/match_single_binding.fixed
index bdf39796ebf..e11dea35204 100644
--- a/src/tools/clippy/tests/ui/match_single_binding.fixed
+++ b/src/tools/clippy/tests/ui/match_single_binding.fixed
@@ -188,3 +188,19 @@ fn issue14634() {
     let id!(_a) = dbg!(b + 1);
     //~^^^ match_single_binding
 }
+
+mod issue14991 {
+    struct AnnoConstWOBlock {
+        inner: [(); {
+            let _n = 1;
+            42
+        }],
+    }
+
+    struct AnnoConstWBlock {
+        inner: [(); {
+            let _n = 1;
+            42
+        }],
+    }
+}
diff --git a/src/tools/clippy/tests/ui/match_single_binding.rs b/src/tools/clippy/tests/ui/match_single_binding.rs
index 419ff95d873..d498da30fc8 100644
--- a/src/tools/clippy/tests/ui/match_single_binding.rs
+++ b/src/tools/clippy/tests/ui/match_single_binding.rs
@@ -249,3 +249,21 @@ fn issue14634() {
     };
     //~^^^ match_single_binding
 }
+
+mod issue14991 {
+    struct AnnoConstWOBlock {
+        inner: [(); match 1 {
+            //~^ match_single_binding
+            _n => 42,
+        }],
+    }
+
+    struct AnnoConstWBlock {
+        inner: [(); {
+            match 1 {
+                //~^ match_single_binding
+                _n => 42,
+            }
+        }],
+    }
+}
diff --git a/src/tools/clippy/tests/ui/match_single_binding.stderr b/src/tools/clippy/tests/ui/match_single_binding.stderr
index bdd0134a5f1..f274f80c81d 100644
--- a/src/tools/clippy/tests/ui/match_single_binding.stderr
+++ b/src/tools/clippy/tests/ui/match_single_binding.stderr
@@ -378,5 +378,38 @@ LL ~     let id!(b) = dbg!(3);
 LL +     let id!(_a) = dbg!(b + 1);
    |
 
-error: aborting due to 27 previous errors
+error: this match could be written as a `let` statement
+  --> tests/ui/match_single_binding.rs:255:21
+   |
+LL |           inner: [(); match 1 {
+   |  _____________________^
+LL | |
+LL | |             _n => 42,
+LL | |         }],
+   | |_________^
+   |
+help: consider using a `let` statement
+   |
+LL ~         inner: [(); {
+LL +             let _n = 1;
+LL +             42
+LL ~         }],
+   |
+
+error: this match could be written as a `let` statement
+  --> tests/ui/match_single_binding.rs:263:13
+   |
+LL | /             match 1 {
+LL | |
+LL | |                 _n => 42,
+LL | |             }
+   | |_____________^
+   |
+help: consider using a `let` statement
+   |
+LL ~             let _n = 1;
+LL +             42
+   |
+
+error: aborting due to 29 previous errors
 
diff --git a/src/tools/clippy/tests/ui/missing_const_for_fn/const_trait.fixed b/src/tools/clippy/tests/ui/missing_const_for_fn/const_trait.fixed
new file mode 100644
index 00000000000..7e0d4fccaae
--- /dev/null
+++ b/src/tools/clippy/tests/ui/missing_const_for_fn/const_trait.fixed
@@ -0,0 +1,36 @@
+#![feature(const_trait_impl)]
+#![warn(clippy::missing_const_for_fn)]
+
+// Reduced test case from https://github.com/rust-lang/rust-clippy/issues/14658
+
+#[const_trait]
+trait ConstTrait {
+    fn method(self);
+}
+
+impl ConstTrait for u32 {
+    fn method(self) {}
+}
+
+impl const ConstTrait for u64 {
+    fn method(self) {}
+}
+
+fn cannot_be_const() {
+    0u32.method();
+}
+
+//~v missing_const_for_fn
+const fn can_be_const() {
+    0u64.method();
+}
+
+// False negative, see FIXME comment in `clipy_utils::qualify_min_const`
+fn could_be_const_but_does_not_trigger<T>(t: T)
+where
+    T: const ConstTrait,
+{
+    t.method();
+}
+
+fn main() {}
diff --git a/src/tools/clippy/tests/ui/missing_const_for_fn/const_trait.rs b/src/tools/clippy/tests/ui/missing_const_for_fn/const_trait.rs
new file mode 100644
index 00000000000..439da4622d7
--- /dev/null
+++ b/src/tools/clippy/tests/ui/missing_const_for_fn/const_trait.rs
@@ -0,0 +1,36 @@
+#![feature(const_trait_impl)]
+#![warn(clippy::missing_const_for_fn)]
+
+// Reduced test case from https://github.com/rust-lang/rust-clippy/issues/14658
+
+#[const_trait]
+trait ConstTrait {
+    fn method(self);
+}
+
+impl ConstTrait for u32 {
+    fn method(self) {}
+}
+
+impl const ConstTrait for u64 {
+    fn method(self) {}
+}
+
+fn cannot_be_const() {
+    0u32.method();
+}
+
+//~v missing_const_for_fn
+fn can_be_const() {
+    0u64.method();
+}
+
+// False negative, see FIXME comment in `clipy_utils::qualify_min_const`
+fn could_be_const_but_does_not_trigger<T>(t: T)
+where
+    T: const ConstTrait,
+{
+    t.method();
+}
+
+fn main() {}
diff --git a/src/tools/clippy/tests/ui/missing_const_for_fn/const_trait.stderr b/src/tools/clippy/tests/ui/missing_const_for_fn/const_trait.stderr
new file mode 100644
index 00000000000..b994b88fac6
--- /dev/null
+++ b/src/tools/clippy/tests/ui/missing_const_for_fn/const_trait.stderr
@@ -0,0 +1,17 @@
+error: this could be a `const fn`
+  --> tests/ui/missing_const_for_fn/const_trait.rs:24:1
+   |
+LL | / fn can_be_const() {
+LL | |     0u64.method();
+LL | | }
+   | |_^
+   |
+   = note: `-D clippy::missing-const-for-fn` implied by `-D warnings`
+   = help: to override `-D warnings` add `#[allow(clippy::missing_const_for_fn)]`
+help: make the function `const`
+   |
+LL | const fn can_be_const() {
+   | +++++
+
+error: aborting due to 1 previous error
+
diff --git a/src/tools/clippy/tests/ui/needless_lifetimes.fixed b/src/tools/clippy/tests/ui/needless_lifetimes.fixed
index ceea4480d0d..15ca409c95b 100644
--- a/src/tools/clippy/tests/ui/needless_lifetimes.fixed
+++ b/src/tools/clippy/tests/ui/needless_lifetimes.fixed
@@ -10,7 +10,7 @@
     clippy::unnecessary_wraps,
     dyn_drop,
     clippy::get_first,
-    mismatched_lifetime_syntaxes,
+    mismatched_lifetime_syntaxes
 )]
 
 extern crate proc_macros;
diff --git a/src/tools/clippy/tests/ui/needless_lifetimes.rs b/src/tools/clippy/tests/ui/needless_lifetimes.rs
index 8432f9e6d2f..af9649d7298 100644
--- a/src/tools/clippy/tests/ui/needless_lifetimes.rs
+++ b/src/tools/clippy/tests/ui/needless_lifetimes.rs
@@ -10,7 +10,7 @@
     clippy::unnecessary_wraps,
     dyn_drop,
     clippy::get_first,
-    mismatched_lifetime_syntaxes,
+    mismatched_lifetime_syntaxes
 )]
 
 extern crate proc_macros;
diff --git a/src/tools/clippy/tests/ui/non_canonical_partial_ord_impl.fixed b/src/tools/clippy/tests/ui/non_canonical_partial_ord_impl.fixed
index 23dbee5a084..6915e1984fb 100644
--- a/src/tools/clippy/tests/ui/non_canonical_partial_ord_impl.fixed
+++ b/src/tools/clippy/tests/ui/non_canonical_partial_ord_impl.fixed
@@ -195,3 +195,19 @@ impl PartialOrd for K {
     //~^ non_canonical_partial_ord_impl
     fn partial_cmp(&self, other: &Self) -> Option<Ordering> { Some(self.cmp(other)) }
 }
+
+// #14574, check that partial_cmp invokes other.cmp
+
+#[derive(Eq, PartialEq)]
+struct L(u32);
+
+impl Ord for L {
+    fn cmp(&self, other: &Self) -> Ordering {
+        todo!();
+    }
+}
+
+impl PartialOrd for L {
+    //~^ non_canonical_partial_ord_impl
+    fn partial_cmp(&self, other: &Self) -> Option<Ordering> { Some(self.cmp(other)) }
+}
diff --git a/src/tools/clippy/tests/ui/non_canonical_partial_ord_impl.rs b/src/tools/clippy/tests/ui/non_canonical_partial_ord_impl.rs
index 12f055a542b..7ce4cdc9aec 100644
--- a/src/tools/clippy/tests/ui/non_canonical_partial_ord_impl.rs
+++ b/src/tools/clippy/tests/ui/non_canonical_partial_ord_impl.rs
@@ -201,3 +201,21 @@ impl PartialOrd for K {
         Ordering::Greater.into()
     }
 }
+
+// #14574, check that partial_cmp invokes other.cmp
+
+#[derive(Eq, PartialEq)]
+struct L(u32);
+
+impl Ord for L {
+    fn cmp(&self, other: &Self) -> Ordering {
+        todo!();
+    }
+}
+
+impl PartialOrd for L {
+    //~^ non_canonical_partial_ord_impl
+    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
+        Some(other.cmp(self))
+    }
+}
diff --git a/src/tools/clippy/tests/ui/non_canonical_partial_ord_impl.stderr b/src/tools/clippy/tests/ui/non_canonical_partial_ord_impl.stderr
index c7de968588f..9bd6b1f726d 100644
--- a/src/tools/clippy/tests/ui/non_canonical_partial_ord_impl.stderr
+++ b/src/tools/clippy/tests/ui/non_canonical_partial_ord_impl.stderr
@@ -44,5 +44,18 @@ LL | ||     }
 LL | |  }
    | |__^
 
-error: aborting due to 3 previous errors
+error: non-canonical implementation of `partial_cmp` on an `Ord` type
+  --> tests/ui/non_canonical_partial_ord_impl.rs:216:1
+   |
+LL | /  impl PartialOrd for L {
+LL | |
+LL | |      fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
+   | | _____________________________________________________________-
+LL | ||         Some(other.cmp(self))
+LL | ||     }
+   | ||_____- help: change this to: `{ Some(self.cmp(other)) }`
+LL | |  }
+   | |__^
+
+error: aborting due to 4 previous errors
 
diff --git a/src/tools/clippy/tests/ui/pointer_format.rs b/src/tools/clippy/tests/ui/pointer_format.rs
new file mode 100644
index 00000000000..0621f966ad1
--- /dev/null
+++ b/src/tools/clippy/tests/ui/pointer_format.rs
@@ -0,0 +1,66 @@
+#![warn(clippy::pointer_format)]
+
+use core::fmt::Debug;
+use core::marker::PhantomData;
+
+#[derive(Debug)]
+struct ContainsPointerDeep {
+    w: WithPointer,
+}
+
+struct ManualDebug {
+    ptr: *const u8,
+}
+
+#[derive(Debug)]
+struct WithPointer {
+    len: usize,
+    ptr: *const u8,
+}
+
+impl std::fmt::Debug for ManualDebug {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        f.write_str("ManualDebug")
+    }
+}
+
+trait Foo {
+    type Assoc: Foo + Debug;
+}
+
+#[derive(Debug)]
+struct S<T: Foo + 'static>(&'static S<T::Assoc>, PhantomData<T>);
+
+#[allow(unused)]
+fn unbounded<T: Foo + Debug + 'static>(s: &S<T>) {
+    format!("{s:?}");
+}
+
+fn main() {
+    let m = &(main as fn());
+    let g = &0;
+    let o = &format!("{m:p}");
+    //~^ pointer_format
+    let _ = format!("{m:?}");
+    //~^ pointer_format
+    println!("{g:p}");
+    //~^ pointer_format
+    panic!("{o:p}");
+    //~^ pointer_format
+    let answer = 42;
+    let x = &raw const answer;
+    let arr = [0u8; 8];
+    let with_ptr = WithPointer { len: 8, ptr: &arr as _ };
+    let _ = format!("{x:?}");
+    //~^ pointer_format
+    print!("{with_ptr:?}");
+    //~^ pointer_format
+    let container = ContainsPointerDeep { w: with_ptr };
+    print!("{container:?}");
+    //~^ pointer_format
+
+    let no_pointer = "foo";
+    println!("{no_pointer:?}");
+    let manual_debug = ManualDebug { ptr: &arr as _ };
+    println!("{manual_debug:?}");
+}
diff --git a/src/tools/clippy/tests/ui/pointer_format.stderr b/src/tools/clippy/tests/ui/pointer_format.stderr
new file mode 100644
index 00000000000..21ba39b8f8c
--- /dev/null
+++ b/src/tools/clippy/tests/ui/pointer_format.stderr
@@ -0,0 +1,47 @@
+error: pointer formatting detected
+  --> tests/ui/pointer_format.rs:42:23
+   |
+LL |     let o = &format!("{m:p}");
+   |                       ^^^^^
+   |
+   = note: `-D clippy::pointer-format` implied by `-D warnings`
+   = help: to override `-D warnings` add `#[allow(clippy::pointer_format)]`
+
+error: pointer formatting detected
+  --> tests/ui/pointer_format.rs:44:22
+   |
+LL |     let _ = format!("{m:?}");
+   |                      ^^^^^
+
+error: pointer formatting detected
+  --> tests/ui/pointer_format.rs:46:15
+   |
+LL |     println!("{g:p}");
+   |               ^^^^^
+
+error: pointer formatting detected
+  --> tests/ui/pointer_format.rs:48:13
+   |
+LL |     panic!("{o:p}");
+   |             ^^^^^
+
+error: pointer formatting detected
+  --> tests/ui/pointer_format.rs:54:22
+   |
+LL |     let _ = format!("{x:?}");
+   |                      ^^^^^
+
+error: pointer formatting detected
+  --> tests/ui/pointer_format.rs:56:13
+   |
+LL |     print!("{with_ptr:?}");
+   |             ^^^^^^^^^^^^
+
+error: pointer formatting detected
+  --> tests/ui/pointer_format.rs:59:13
+   |
+LL |     print!("{container:?}");
+   |             ^^^^^^^^^^^^^
+
+error: aborting due to 7 previous errors
+
diff --git a/src/tools/clippy/tests/ui/print_literal.fixed b/src/tools/clippy/tests/ui/print_literal.fixed
index 24c45a4a61b..ebfe19c700e 100644
--- a/src/tools/clippy/tests/ui/print_literal.fixed
+++ b/src/tools/clippy/tests/ui/print_literal.fixed
@@ -94,3 +94,14 @@ fn issue_13959() {
 "
     );
 }
+
+fn issue_14930() {
+    println!("Hello x is {0:2$.1$}", 0.01, 2, 3);
+    //~^ print_literal
+    println!("Hello x is {0:2$.1$}", 0.01, 2, 3);
+    //~^ print_literal
+    println!("Hello x is {0:2$.1$}", 0.01, 2, 3);
+    //~^ print_literal
+    println!("Hello x is {0:2$.1$}", 0.01, 2, 3);
+    //~^ print_literal
+}
diff --git a/src/tools/clippy/tests/ui/print_literal.rs b/src/tools/clippy/tests/ui/print_literal.rs
index 42ae589ca63..8f3d9be0698 100644
--- a/src/tools/clippy/tests/ui/print_literal.rs
+++ b/src/tools/clippy/tests/ui/print_literal.rs
@@ -95,3 +95,14 @@ fn issue_13959() {
 "#
     );
 }
+
+fn issue_14930() {
+    println!("Hello {3} is {0:2$.1$}", 0.01, 2, 3, "x");
+    //~^ print_literal
+    println!("Hello {2} is {0:3$.1$}", 0.01, 2, "x", 3);
+    //~^ print_literal
+    println!("Hello {1} is {0:3$.2$}", 0.01, "x", 2, 3);
+    //~^ print_literal
+    println!("Hello {0} is {1:3$.2$}", "x", 0.01, 2, 3);
+    //~^ print_literal
+}
diff --git a/src/tools/clippy/tests/ui/print_literal.stderr b/src/tools/clippy/tests/ui/print_literal.stderr
index da663000686..1c378017d15 100644
--- a/src/tools/clippy/tests/ui/print_literal.stderr
+++ b/src/tools/clippy/tests/ui/print_literal.stderr
@@ -229,5 +229,53 @@ LL +         bar
 LL ~ "
    |
 
-error: aborting due to 18 previous errors
+error: literal with an empty format string
+  --> tests/ui/print_literal.rs:100:52
+   |
+LL |     println!("Hello {3} is {0:2$.1$}", 0.01, 2, 3, "x");
+   |                                                    ^^^
+   |
+help: try
+   |
+LL -     println!("Hello {3} is {0:2$.1$}", 0.01, 2, 3, "x");
+LL +     println!("Hello x is {0:2$.1$}", 0.01, 2, 3);
+   |
+
+error: literal with an empty format string
+  --> tests/ui/print_literal.rs:102:49
+   |
+LL |     println!("Hello {2} is {0:3$.1$}", 0.01, 2, "x", 3);
+   |                                                 ^^^
+   |
+help: try
+   |
+LL -     println!("Hello {2} is {0:3$.1$}", 0.01, 2, "x", 3);
+LL +     println!("Hello x is {0:2$.1$}", 0.01, 2, 3);
+   |
+
+error: literal with an empty format string
+  --> tests/ui/print_literal.rs:104:46
+   |
+LL |     println!("Hello {1} is {0:3$.2$}", 0.01, "x", 2, 3);
+   |                                              ^^^
+   |
+help: try
+   |
+LL -     println!("Hello {1} is {0:3$.2$}", 0.01, "x", 2, 3);
+LL +     println!("Hello x is {0:2$.1$}", 0.01, 2, 3);
+   |
+
+error: literal with an empty format string
+  --> tests/ui/print_literal.rs:106:40
+   |
+LL |     println!("Hello {0} is {1:3$.2$}", "x", 0.01, 2, 3);
+   |                                        ^^^
+   |
+help: try
+   |
+LL -     println!("Hello {0} is {1:3$.2$}", "x", 0.01, 2, 3);
+LL +     println!("Hello x is {0:2$.1$}", 0.01, 2, 3);
+   |
+
+error: aborting due to 22 previous errors
 
diff --git a/src/tools/clippy/tests/ui/semicolon_outside_block.fixed b/src/tools/clippy/tests/ui/semicolon_outside_block.fixed
index 52fae9a3aff..a3be80b4928 100644
--- a/src/tools/clippy/tests/ui/semicolon_outside_block.fixed
+++ b/src/tools/clippy/tests/ui/semicolon_outside_block.fixed
@@ -96,3 +96,28 @@ fn main() {
 
     unit_fn_block()
 }
+
+fn issue14926() {
+    macro_rules! gen_code {
+        [$l:lifetime: $b:block, $b2: block $(,)?] => {
+            $l: loop {
+                $b
+                break $l;
+            }
+            $l: loop {
+                $b2
+                break $l;
+            }
+        };
+    }
+
+    gen_code! {
+        'root:
+        {
+            println!("Block1");
+        },
+        {
+            println!("Block2");
+        },
+    }
+}
diff --git a/src/tools/clippy/tests/ui/semicolon_outside_block.rs b/src/tools/clippy/tests/ui/semicolon_outside_block.rs
index 5975e66fbb8..3b7bf68029f 100644
--- a/src/tools/clippy/tests/ui/semicolon_outside_block.rs
+++ b/src/tools/clippy/tests/ui/semicolon_outside_block.rs
@@ -96,3 +96,28 @@ fn main() {
 
     unit_fn_block()
 }
+
+fn issue14926() {
+    macro_rules! gen_code {
+        [$l:lifetime: $b:block, $b2: block $(,)?] => {
+            $l: loop {
+                $b
+                break $l;
+            }
+            $l: loop {
+                $b2
+                break $l;
+            }
+        };
+    }
+
+    gen_code! {
+        'root:
+        {
+            println!("Block1");
+        },
+        {
+            println!("Block2");
+        },
+    }
+}
diff --git a/src/tools/clippy/tests/ui/std_instead_of_core.fixed b/src/tools/clippy/tests/ui/std_instead_of_core.fixed
index ab2e801eee2..1820ade422f 100644
--- a/src/tools/clippy/tests/ui/std_instead_of_core.fixed
+++ b/src/tools/clippy/tests/ui/std_instead_of_core.fixed
@@ -90,3 +90,9 @@ fn msrv_1_76(_: std::net::IpAddr) {}
 #[clippy::msrv = "1.77"]
 fn msrv_1_77(_: core::net::IpAddr) {}
 //~^ std_instead_of_core
+
+#[warn(clippy::std_instead_of_core)]
+#[rustfmt::skip]
+fn issue14982() {
+    use std::{collections::HashMap, hash::Hash};
+}
diff --git a/src/tools/clippy/tests/ui/std_instead_of_core.rs b/src/tools/clippy/tests/ui/std_instead_of_core.rs
index f760b3561ae..32c49330981 100644
--- a/src/tools/clippy/tests/ui/std_instead_of_core.rs
+++ b/src/tools/clippy/tests/ui/std_instead_of_core.rs
@@ -90,3 +90,9 @@ fn msrv_1_76(_: std::net::IpAddr) {}
 #[clippy::msrv = "1.77"]
 fn msrv_1_77(_: std::net::IpAddr) {}
 //~^ std_instead_of_core
+
+#[warn(clippy::std_instead_of_core)]
+#[rustfmt::skip]
+fn issue14982() {
+    use std::{collections::HashMap, hash::Hash};
+}
diff --git a/src/tools/clippy/tests/ui/unit_arg.rs b/src/tools/clippy/tests/ui/unit_arg.rs
index 22a6a26dab6..4208efad677 100644
--- a/src/tools/clippy/tests/ui/unit_arg.rs
+++ b/src/tools/clippy/tests/ui/unit_arg.rs
@@ -151,3 +151,27 @@ fn main() {
     bad();
     ok();
 }
+
+fn issue14857() {
+    let fn_take_unit = |_: ()| {};
+    fn some_other_fn(_: &i32) {}
+
+    macro_rules! mac {
+        (def) => {
+            Default::default()
+        };
+        (func $f:expr) => {
+            $f()
+        };
+        (nonempty_block $e:expr) => {{
+            some_other_fn(&$e);
+            $e
+        }};
+    }
+    fn_take_unit(mac!(def));
+    //~^ unit_arg
+    fn_take_unit(mac!(func Default::default));
+    //~^ unit_arg
+    fn_take_unit(mac!(nonempty_block Default::default()));
+    //~^ unit_arg
+}
diff --git a/src/tools/clippy/tests/ui/unit_arg.stderr b/src/tools/clippy/tests/ui/unit_arg.stderr
index 6c333d9792d..0dcfb02b9fa 100644
--- a/src/tools/clippy/tests/ui/unit_arg.stderr
+++ b/src/tools/clippy/tests/ui/unit_arg.stderr
@@ -199,5 +199,26 @@ LL ~     foo(1);
 LL +     Some(())
    |
 
-error: aborting due to 10 previous errors
+error: passing a unit value to a function
+  --> tests/ui/unit_arg.rs:171:5
+   |
+LL |     fn_take_unit(mac!(def));
+   |     ^^^^^^^^^^^^^^^^^^^^^^^
+   |
+
+error: passing a unit value to a function
+  --> tests/ui/unit_arg.rs:173:5
+   |
+LL |     fn_take_unit(mac!(func Default::default));
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+
+error: passing a unit value to a function
+  --> tests/ui/unit_arg.rs:175:5
+   |
+LL |     fn_take_unit(mac!(nonempty_block Default::default()));
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+
+error: aborting due to 13 previous errors
 
diff --git a/src/tools/clippy/tests/ui/unit_arg_empty_blocks.fixed b/src/tools/clippy/tests/ui/unit_arg_empty_blocks.fixed
deleted file mode 100644
index b045a33608d..00000000000
--- a/src/tools/clippy/tests/ui/unit_arg_empty_blocks.fixed
+++ /dev/null
@@ -1,34 +0,0 @@
-#![warn(clippy::unit_arg)]
-#![allow(unused_must_use, unused_variables)]
-#![allow(clippy::no_effect, clippy::uninlined_format_args)]
-
-use std::fmt::Debug;
-
-fn foo<T: Debug>(t: T) {
-    println!("{:?}", t);
-}
-
-fn foo3<T1: Debug, T2: Debug, T3: Debug>(t1: T1, t2: T2, t3: T3) {
-    println!("{:?}, {:?}, {:?}", t1, t2, t3);
-}
-
-fn bad() {
-    foo(());
-    //~^ unit_arg
-    foo3((), 2, 2);
-    //~^ unit_arg
-    foo(0);
-    taking_two_units((), ());
-    //~^ unit_arg
-    foo(0);
-    foo(1);
-    taking_three_units((), (), ());
-    //~^ unit_arg
-}
-
-fn taking_two_units(a: (), b: ()) {}
-fn taking_three_units(a: (), b: (), c: ()) {}
-
-fn main() {
-    bad();
-}
diff --git a/src/tools/clippy/tests/ui/unit_arg_empty_blocks.rs b/src/tools/clippy/tests/ui/unit_arg_empty_blocks.rs
deleted file mode 100644
index ab305913f3f..00000000000
--- a/src/tools/clippy/tests/ui/unit_arg_empty_blocks.rs
+++ /dev/null
@@ -1,31 +0,0 @@
-#![warn(clippy::unit_arg)]
-#![allow(unused_must_use, unused_variables)]
-#![allow(clippy::no_effect, clippy::uninlined_format_args)]
-
-use std::fmt::Debug;
-
-fn foo<T: Debug>(t: T) {
-    println!("{:?}", t);
-}
-
-fn foo3<T1: Debug, T2: Debug, T3: Debug>(t1: T1, t2: T2, t3: T3) {
-    println!("{:?}, {:?}, {:?}", t1, t2, t3);
-}
-
-fn bad() {
-    foo({});
-    //~^ unit_arg
-    foo3({}, 2, 2);
-    //~^ unit_arg
-    taking_two_units({}, foo(0));
-    //~^ unit_arg
-    taking_three_units({}, foo(0), foo(1));
-    //~^ unit_arg
-}
-
-fn taking_two_units(a: (), b: ()) {}
-fn taking_three_units(a: (), b: (), c: ()) {}
-
-fn main() {
-    bad();
-}
diff --git a/src/tools/clippy/tests/ui/unit_arg_empty_blocks.stderr b/src/tools/clippy/tests/ui/unit_arg_empty_blocks.stderr
deleted file mode 100644
index 2c686d58ecc..00000000000
--- a/src/tools/clippy/tests/ui/unit_arg_empty_blocks.stderr
+++ /dev/null
@@ -1,46 +0,0 @@
-error: passing a unit value to a function
-  --> tests/ui/unit_arg_empty_blocks.rs:16:5
-   |
-LL |     foo({});
-   |     ^^^^--^
-   |         |
-   |         help: use a unit literal instead: `()`
-   |
-   = note: `-D clippy::unit-arg` implied by `-D warnings`
-   = help: to override `-D warnings` add `#[allow(clippy::unit_arg)]`
-
-error: passing a unit value to a function
-  --> tests/ui/unit_arg_empty_blocks.rs:18:5
-   |
-LL |     foo3({}, 2, 2);
-   |     ^^^^^--^^^^^^^
-   |          |
-   |          help: use a unit literal instead: `()`
-
-error: passing unit values to a function
-  --> tests/ui/unit_arg_empty_blocks.rs:20:5
-   |
-LL |     taking_two_units({}, foo(0));
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-help: move the expression in front of the call and replace it with the unit literal `()`
-   |
-LL ~     foo(0);
-LL ~     taking_two_units((), ());
-   |
-
-error: passing unit values to a function
-  --> tests/ui/unit_arg_empty_blocks.rs:22:5
-   |
-LL |     taking_three_units({}, foo(0), foo(1));
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-help: move the expressions in front of the call and replace them with the unit literal `()`
-   |
-LL ~     foo(0);
-LL +     foo(1);
-LL ~     taking_three_units((), (), ());
-   |
-
-error: aborting due to 4 previous errors
-
diff --git a/src/tools/clippy/tests/ui/unit_arg_fixable.fixed b/src/tools/clippy/tests/ui/unit_arg_fixable.fixed
new file mode 100644
index 00000000000..03353a14081
--- /dev/null
+++ b/src/tools/clippy/tests/ui/unit_arg_fixable.fixed
@@ -0,0 +1,78 @@
+#![warn(clippy::unit_arg)]
+#![allow(unused_must_use, unused_variables)]
+#![allow(clippy::no_effect, clippy::uninlined_format_args)]
+
+use std::fmt::Debug;
+
+fn foo<T: Debug>(t: T) {
+    println!("{:?}", t);
+}
+
+fn foo3<T1: Debug, T2: Debug, T3: Debug>(t1: T1, t2: T2, t3: T3) {
+    println!("{:?}, {:?}, {:?}", t1, t2, t3);
+}
+
+fn bad() {
+    foo(());
+    //~^ unit_arg
+    foo3((), 2, 2);
+    //~^ unit_arg
+    foo(0);
+    taking_two_units((), ());
+    //~^ unit_arg
+    foo(0);
+    foo(1);
+    taking_three_units((), (), ());
+    //~^ unit_arg
+}
+
+fn taking_two_units(a: (), b: ()) {}
+fn taking_three_units(a: (), b: (), c: ()) {}
+
+fn main() {
+    bad();
+}
+
+fn issue14857() {
+    let fn_take_unit = |_: ()| {};
+    fn_take_unit(());
+    //~^ unit_arg
+
+    fn some_other_fn(_: &i32) {}
+
+    macro_rules! another_mac {
+        () => {
+            some_other_fn(&Default::default())
+        };
+        ($e:expr) => {
+            some_other_fn(&$e)
+        };
+    }
+
+    another_mac!();
+    fn_take_unit(());
+    //~^ unit_arg
+    another_mac!(1);
+    fn_take_unit(());
+    //~^ unit_arg
+
+    macro_rules! mac {
+        (nondef $e:expr) => {
+            $e
+        };
+        (empty_block) => {{}};
+    }
+    fn_take_unit(mac!(nondef ()));
+    //~^ unit_arg
+    mac!(empty_block);
+    fn_take_unit(());
+    //~^ unit_arg
+
+    fn def<T: Default>() -> T {
+        Default::default()
+    }
+
+    let _: () = def();
+    fn_take_unit(());
+    //~^ unit_arg
+}
diff --git a/src/tools/clippy/tests/ui/unit_arg_fixable.rs b/src/tools/clippy/tests/ui/unit_arg_fixable.rs
new file mode 100644
index 00000000000..03fd96efdf9
--- /dev/null
+++ b/src/tools/clippy/tests/ui/unit_arg_fixable.rs
@@ -0,0 +1,71 @@
+#![warn(clippy::unit_arg)]
+#![allow(unused_must_use, unused_variables)]
+#![allow(clippy::no_effect, clippy::uninlined_format_args)]
+
+use std::fmt::Debug;
+
+fn foo<T: Debug>(t: T) {
+    println!("{:?}", t);
+}
+
+fn foo3<T1: Debug, T2: Debug, T3: Debug>(t1: T1, t2: T2, t3: T3) {
+    println!("{:?}, {:?}, {:?}", t1, t2, t3);
+}
+
+fn bad() {
+    foo({});
+    //~^ unit_arg
+    foo3({}, 2, 2);
+    //~^ unit_arg
+    taking_two_units({}, foo(0));
+    //~^ unit_arg
+    taking_three_units({}, foo(0), foo(1));
+    //~^ unit_arg
+}
+
+fn taking_two_units(a: (), b: ()) {}
+fn taking_three_units(a: (), b: (), c: ()) {}
+
+fn main() {
+    bad();
+}
+
+fn issue14857() {
+    let fn_take_unit = |_: ()| {};
+    fn_take_unit(Default::default());
+    //~^ unit_arg
+
+    fn some_other_fn(_: &i32) {}
+
+    macro_rules! another_mac {
+        () => {
+            some_other_fn(&Default::default())
+        };
+        ($e:expr) => {
+            some_other_fn(&$e)
+        };
+    }
+
+    fn_take_unit(another_mac!());
+    //~^ unit_arg
+    fn_take_unit(another_mac!(1));
+    //~^ unit_arg
+
+    macro_rules! mac {
+        (nondef $e:expr) => {
+            $e
+        };
+        (empty_block) => {{}};
+    }
+    fn_take_unit(mac!(nondef Default::default()));
+    //~^ unit_arg
+    fn_take_unit(mac!(empty_block));
+    //~^ unit_arg
+
+    fn def<T: Default>() -> T {
+        Default::default()
+    }
+
+    fn_take_unit(def());
+    //~^ unit_arg
+}
diff --git a/src/tools/clippy/tests/ui/unit_arg_fixable.stderr b/src/tools/clippy/tests/ui/unit_arg_fixable.stderr
new file mode 100644
index 00000000000..ccd5aa8322f
--- /dev/null
+++ b/src/tools/clippy/tests/ui/unit_arg_fixable.stderr
@@ -0,0 +1,110 @@
+error: passing a unit value to a function
+  --> tests/ui/unit_arg_fixable.rs:16:5
+   |
+LL |     foo({});
+   |     ^^^^--^
+   |         |
+   |         help: use a unit literal instead: `()`
+   |
+   = note: `-D clippy::unit-arg` implied by `-D warnings`
+   = help: to override `-D warnings` add `#[allow(clippy::unit_arg)]`
+
+error: passing a unit value to a function
+  --> tests/ui/unit_arg_fixable.rs:18:5
+   |
+LL |     foo3({}, 2, 2);
+   |     ^^^^^--^^^^^^^
+   |          |
+   |          help: use a unit literal instead: `()`
+
+error: passing unit values to a function
+  --> tests/ui/unit_arg_fixable.rs:20:5
+   |
+LL |     taking_two_units({}, foo(0));
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: move the expression in front of the call and replace it with the unit literal `()`
+   |
+LL ~     foo(0);
+LL ~     taking_two_units((), ());
+   |
+
+error: passing unit values to a function
+  --> tests/ui/unit_arg_fixable.rs:22:5
+   |
+LL |     taking_three_units({}, foo(0), foo(1));
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: move the expressions in front of the call and replace them with the unit literal `()`
+   |
+LL ~     foo(0);
+LL +     foo(1);
+LL ~     taking_three_units((), (), ());
+   |
+
+error: passing a unit value to a function
+  --> tests/ui/unit_arg_fixable.rs:35:5
+   |
+LL |     fn_take_unit(Default::default());
+   |     ^^^^^^^^^^^^^------------------^
+   |                  |
+   |                  help: use a unit literal instead: `()`
+
+error: passing a unit value to a function
+  --> tests/ui/unit_arg_fixable.rs:49:5
+   |
+LL |     fn_take_unit(another_mac!());
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: move the expression in front of the call and replace it with the unit literal `()`
+   |
+LL ~     another_mac!();
+LL ~     fn_take_unit(());
+   |
+
+error: passing a unit value to a function
+  --> tests/ui/unit_arg_fixable.rs:51:5
+   |
+LL |     fn_take_unit(another_mac!(1));
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: move the expression in front of the call and replace it with the unit literal `()`
+   |
+LL ~     another_mac!(1);
+LL ~     fn_take_unit(());
+   |
+
+error: passing a unit value to a function
+  --> tests/ui/unit_arg_fixable.rs:60:5
+   |
+LL |     fn_take_unit(mac!(nondef Default::default()));
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^------------------^^
+   |                              |
+   |                              help: use a unit literal instead: `()`
+
+error: passing a unit value to a function
+  --> tests/ui/unit_arg_fixable.rs:62:5
+   |
+LL |     fn_take_unit(mac!(empty_block));
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: move the expression in front of the call and replace it with the unit literal `()`
+   |
+LL ~     mac!(empty_block);
+LL ~     fn_take_unit(());
+   |
+
+error: passing a unit value to a function
+  --> tests/ui/unit_arg_fixable.rs:69:5
+   |
+LL |     fn_take_unit(def());
+   |     ^^^^^^^^^^^^^^^^^^^
+   |
+help: move the expression in front of the call and replace it with the unit literal `()`
+   |
+LL ~     let _: () = def();
+LL ~     fn_take_unit(());
+   |
+
+error: aborting due to 10 previous errors
+
diff --git a/src/tools/clippy/tests/ui/unused_unit.edition2021.fixed b/src/tools/clippy/tests/ui/unused_unit.edition2021.fixed
index 93dd58b8e9d..def8ef86e3c 100644
--- a/src/tools/clippy/tests/ui/unused_unit.edition2021.fixed
+++ b/src/tools/clippy/tests/ui/unused_unit.edition2021.fixed
@@ -143,4 +143,10 @@ mod issue14577 {
             todo!()
         }
     }
-}
\ No newline at end of file
+}
+
+mod pr14962 {
+    #[allow(unused_parens)]
+    type UnusedParensButNoUnit = Box<dyn (Fn())>;
+}
+
diff --git a/src/tools/clippy/tests/ui/unused_unit.edition2024.fixed b/src/tools/clippy/tests/ui/unused_unit.edition2024.fixed
index 987d901b97d..f908b958b19 100644
--- a/src/tools/clippy/tests/ui/unused_unit.edition2024.fixed
+++ b/src/tools/clippy/tests/ui/unused_unit.edition2024.fixed
@@ -143,4 +143,10 @@ mod issue14577 {
             todo!()
         }
     }
-}
\ No newline at end of file
+}
+
+mod pr14962 {
+    #[allow(unused_parens)]
+    type UnusedParensButNoUnit = Box<dyn (Fn())>;
+}
+
diff --git a/src/tools/clippy/tests/ui/unused_unit.rs b/src/tools/clippy/tests/ui/unused_unit.rs
index b7645f7b6a2..7298ec40cc2 100644
--- a/src/tools/clippy/tests/ui/unused_unit.rs
+++ b/src/tools/clippy/tests/ui/unused_unit.rs
@@ -143,4 +143,10 @@ mod issue14577 {
             todo!()
         }
     }
-}
\ No newline at end of file
+}
+
+mod pr14962 {
+    #[allow(unused_parens)]
+    type UnusedParensButNoUnit = Box<dyn (Fn())>;
+}
+
diff --git a/src/tools/clippy/tests/ui/write_literal.fixed b/src/tools/clippy/tests/ui/write_literal.fixed
index e84f768e33d..29352fd468e 100644
--- a/src/tools/clippy/tests/ui/write_literal.fixed
+++ b/src/tools/clippy/tests/ui/write_literal.fixed
@@ -87,3 +87,15 @@ fn issue_13959() {
 "
     );
 }
+
+fn issue_14930() {
+    let mut v = Vec::new();
+    writeln!(v, "Hello x is {0:2$.1$}", 0.01, 2, 3);
+    //~^ write_literal
+    writeln!(v, "Hello x is {0:2$.1$}", 0.01, 2, 3);
+    //~^ write_literal
+    writeln!(v, "Hello x is {0:2$.1$}", 0.01, 2, 3);
+    //~^ write_literal
+    writeln!(v, "Hello x is {0:2$.1$}", 0.01, 2, 3);
+    //~^ write_literal
+}
diff --git a/src/tools/clippy/tests/ui/write_literal.rs b/src/tools/clippy/tests/ui/write_literal.rs
index fc29fcbede7..92872752759 100644
--- a/src/tools/clippy/tests/ui/write_literal.rs
+++ b/src/tools/clippy/tests/ui/write_literal.rs
@@ -88,3 +88,15 @@ fn issue_13959() {
 "#
     );
 }
+
+fn issue_14930() {
+    let mut v = Vec::new();
+    writeln!(v, "Hello {3} is {0:2$.1$}", 0.01, 2, 3, "x");
+    //~^ write_literal
+    writeln!(v, "Hello {2} is {0:3$.1$}", 0.01, 2, "x", 3);
+    //~^ write_literal
+    writeln!(v, "Hello {1} is {0:3$.2$}", 0.01, "x", 2, 3);
+    //~^ write_literal
+    writeln!(v, "Hello {0} is {1:3$.2$}", "x", 0.01, 2, 3);
+    //~^ write_literal
+}
diff --git a/src/tools/clippy/tests/ui/write_literal.stderr b/src/tools/clippy/tests/ui/write_literal.stderr
index d53c2a7de2e..ca37406c811 100644
--- a/src/tools/clippy/tests/ui/write_literal.stderr
+++ b/src/tools/clippy/tests/ui/write_literal.stderr
@@ -181,5 +181,53 @@ LL +         bar
 LL ~ "
    |
 
-error: aborting due to 14 previous errors
+error: literal with an empty format string
+  --> tests/ui/write_literal.rs:94:55
+   |
+LL |     writeln!(v, "Hello {3} is {0:2$.1$}", 0.01, 2, 3, "x");
+   |                                                       ^^^
+   |
+help: try
+   |
+LL -     writeln!(v, "Hello {3} is {0:2$.1$}", 0.01, 2, 3, "x");
+LL +     writeln!(v, "Hello x is {0:2$.1$}", 0.01, 2, 3);
+   |
+
+error: literal with an empty format string
+  --> tests/ui/write_literal.rs:96:52
+   |
+LL |     writeln!(v, "Hello {2} is {0:3$.1$}", 0.01, 2, "x", 3);
+   |                                                    ^^^
+   |
+help: try
+   |
+LL -     writeln!(v, "Hello {2} is {0:3$.1$}", 0.01, 2, "x", 3);
+LL +     writeln!(v, "Hello x is {0:2$.1$}", 0.01, 2, 3);
+   |
+
+error: literal with an empty format string
+  --> tests/ui/write_literal.rs:98:49
+   |
+LL |     writeln!(v, "Hello {1} is {0:3$.2$}", 0.01, "x", 2, 3);
+   |                                                 ^^^
+   |
+help: try
+   |
+LL -     writeln!(v, "Hello {1} is {0:3$.2$}", 0.01, "x", 2, 3);
+LL +     writeln!(v, "Hello x is {0:2$.1$}", 0.01, 2, 3);
+   |
+
+error: literal with an empty format string
+  --> tests/ui/write_literal.rs:100:43
+   |
+LL |     writeln!(v, "Hello {0} is {1:3$.2$}", "x", 0.01, 2, 3);
+   |                                           ^^^
+   |
+help: try
+   |
+LL -     writeln!(v, "Hello {0} is {1:3$.2$}", "x", 0.01, 2, 3);
+LL +     writeln!(v, "Hello x is {0:2$.1$}", 0.01, 2, 3);
+   |
+
+error: aborting due to 18 previous errors
 
diff --git a/src/tools/clippy/tests/ui/zombie_processes.rs b/src/tools/clippy/tests/ui/zombie_processes.rs
index 395f9dd2def..e81b5fd4f3e 100644
--- a/src/tools/clippy/tests/ui/zombie_processes.rs
+++ b/src/tools/clippy/tests/ui/zombie_processes.rs
@@ -198,3 +198,13 @@ mod issue14677 {
         child.wait().unwrap();
     }
 }
+
+fn issue14911() -> std::io::Result<String> {
+    let (mut recv, send) = std::io::pipe()?;
+    let mut command = Command::new("ls")
+        .stdout(send.try_clone()?)
+        .spawn()
+        .expect("Could not spawn new process...");
+    command.wait()?;
+    Ok("".into())
+}
diff --git a/src/tools/clippy/util/gh-pages/script.js b/src/tools/clippy/util/gh-pages/script.js
index fec883938d6..285aa34e701 100644
--- a/src/tools/clippy/util/gh-pages/script.js
+++ b/src/tools/clippy/util/gh-pages/script.js
@@ -602,7 +602,7 @@ filters.filterLints();
 updateLintCount();
 
 function updateLintCount() {
-    const allLints = filters.getAllLints();
+    const allLints = filters.getAllLints().filter(lint => lint.group != "deprecated");
     const totalLints = allLints.length;
     
     const countElement = document.getElementById("lint-count");
diff --git a/src/tools/compiletest/src/directive-list.rs b/src/tools/compiletest/src/directive-list.rs
index 1406553c9ea..2ecb4fc8652 100644
--- a/src/tools/compiletest/src/directive-list.rs
+++ b/src/tools/compiletest/src/directive-list.rs
@@ -166,6 +166,7 @@ const KNOWN_DIRECTIVE_NAMES: &[&str] = &[
     "needs-subprocess",
     "needs-symlink",
     "needs-target-has-atomic",
+    "needs-target-std",
     "needs-threads",
     "needs-unwind",
     "needs-wasmtime",
diff --git a/src/tools/compiletest/src/header/needs.rs b/src/tools/compiletest/src/header/needs.rs
index 2ace40c490b..b1165f4bb18 100644
--- a/src/tools/compiletest/src/header/needs.rs
+++ b/src/tools/compiletest/src/header/needs.rs
@@ -174,6 +174,11 @@ pub(super) fn handle_needs(
             condition: config.with_std_debug_assertions,
             ignore_reason: "ignored if std wasn't built with debug assertions",
         },
+        Need {
+            name: "needs-target-std",
+            condition: build_helper::targets::target_supports_std(&config.target),
+            ignore_reason: "ignored if target does not support std",
+        },
     ];
 
     let (name, rest) = match ln.split_once([':', ' ']) {
diff --git a/src/tools/compiletest/src/header/tests.rs b/src/tools/compiletest/src/header/tests.rs
index e7e5ff0ab00..31b49b09bcd 100644
--- a/src/tools/compiletest/src/header/tests.rs
+++ b/src/tools/compiletest/src/header/tests.rs
@@ -945,3 +945,14 @@ fn test_ignore_auxiliary() {
     let config = cfg().build();
     assert!(check_ignore(&config, "//@ ignore-auxiliary"));
 }
+
+#[test]
+fn test_needs_target_std() {
+    // Cherry-picks two targets:
+    // 1. `x86_64-unknown-none`: Tier 2, intentionally never supports std.
+    // 2. `x86_64-unknown-linux-gnu`: Tier 1, always supports std.
+    let config = cfg().target("x86_64-unknown-none").build();
+    assert!(check_ignore(&config, "//@ needs-target-std"));
+    let config = cfg().target("x86_64-unknown-linux-gnu").build();
+    assert!(!check_ignore(&config, "//@ needs-target-std"));
+}
diff --git a/src/tools/compiletest/src/util.rs b/src/tools/compiletest/src/util.rs
index 81f5679aead..202582bea8c 100644
--- a/src/tools/compiletest/src/util.rs
+++ b/src/tools/compiletest/src/util.rs
@@ -29,6 +29,7 @@ fn path_div() -> &'static str {
 pub fn logv(config: &Config, s: String) {
     debug!("{}", s);
     if config.verbose {
+        // Note: `./x test ... --verbose --no-capture` is needed to see this print.
         println!("{}", s);
     }
 }
diff --git a/src/tools/miri/Cargo.lock b/src/tools/miri/Cargo.lock
index 6f4bd3eab51..192d4f444c2 100644
--- a/src/tools/miri/Cargo.lock
+++ b/src/tools/miri/Cargo.lock
@@ -555,7 +555,6 @@ dependencies = [
  "tempfile",
  "tikv-jemalloc-sys",
  "ui_test",
- "windows-sys",
 ]
 
 [[package]]
diff --git a/src/tools/miri/Cargo.toml b/src/tools/miri/Cargo.toml
index e4d7abdb0f7..a314488bb25 100644
--- a/src/tools/miri/Cargo.toml
+++ b/src/tools/miri/Cargo.toml
@@ -40,13 +40,6 @@ libc = "0.2"
 libffi = "4.0.0"
 libloading = "0.8"
 
-[target.'cfg(target_family = "windows")'.dependencies]
-windows-sys = { version = "0.59", features = [
-    "Win32_Foundation",
-    "Win32_System_IO",
-    "Win32_Storage_FileSystem",
-] }
-
 [dev-dependencies]
 ui_test = "0.29.1"
 colored = "2"
diff --git a/src/tools/miri/README.md b/src/tools/miri/README.md
index de521393cd0..5554c7975ff 100644
--- a/src/tools/miri/README.md
+++ b/src/tools/miri/README.md
@@ -286,6 +286,11 @@ environment variable. We first document the most relevant and most commonly used
   specific circumstances, but Miri's behavior will also be more stable across versions and targets.
   This is equivalent to `-Zmiri-fixed-schedule -Zmiri-compare-exchange-weak-failure-rate=0.0
   -Zmiri-address-reuse-cross-thread-rate=0.0 -Zmiri-disable-weak-memory-emulation`.
+* `-Zmiri-deterministic-floats` makes Miri's floating-point behavior fully deterministic. This means
+  that operations will always return the preferred NaN, imprecise operations will not have any
+  random error applied to them, and `min`/`max` as "maybe fused" multiply-add all behave
+  deterministically. Note that Miri still uses host floats for some operations, so behavior can
+  still differ depending on the host target and setup.
 * `-Zmiri-disable-isolation` disables host isolation. As a consequence,
   the program has access to host resources such as environment variables, file
   systems, and randomness.
@@ -396,18 +401,22 @@ to Miri failing to detect cases of undefined behavior in a program.
 * `-Zmiri-force-intrinsic-fallback` forces the use of the "fallback" body for all intrinsics that
   have one. This is useful to test the fallback bodies, but should not be used otherwise. It is
   **unsound** since the fallback body might not be checking for all UB.
-* `-Zmiri-native-lib=<path to a shared object file>` is an experimental flag for providing support
-  for calling native functions from inside the interpreter via FFI. The flag is supported only on
-  Unix systems. Functions not provided by that file are still executed via the usual Miri shims.
+* `-Zmiri-native-lib=<path to a shared object file or folder>` is an experimental flag for providing
+  support for calling native functions from inside the interpreter via FFI. The flag is supported
+  only on Unix systems. Functions not provided by that file are still executed via the usual Miri
+  shims. If a path to a directory is specified, all files in that directory are included
+  non-recursively. This flag can be passed multiple times to specify multiple files and/or
+  directories.
   **WARNING**: If an invalid/incorrect `.so` file is specified, this can cause Undefined Behavior in
-  Miri itself! And of course, Miri cannot do any checks on the actions taken by the native code.
+  Miri itself! And of course, Miri often cannot do any checks on the actions taken by the native code.
   Note that Miri has its own handling of file descriptors, so if you want to replace *some*
   functions working on file descriptors, you will have to replace *all* of them, or the two kinds of
-  file descriptors will be mixed up. This is **work in progress**; currently, only integer and
-  pointers arguments and return values are supported and memory allocated by the native code cannot
-  be accessed from Rust (only the other way around). Native code must not spawn threads that keep
-  running in the background after the call has returned to Rust and that access Rust-allocated
-  memory. Finally, the flag is **unsound** in the sense that Miri stops tracking details such as
+  file descriptors will be mixed up.
+  This is **work in progress**; currently, only integer and pointers arguments and return values are
+  supported and memory allocated by the native code cannot be accessed from Rust (only the other way
+  around). Native code must not spawn threads that keep running in the background after the call has
+  returned to Rust and that access Rust-allocated memory.
+  Finally, the flag is **unsound** in the sense that Miri stops tracking details such as
   initialization and provenance on memory shared with native code, so it is easily possible to write
   code that has UB which is missed by Miri.
 * `-Zmiri-measureme=<name>` enables `measureme` profiling for the interpreted program.
@@ -458,6 +467,10 @@ to Miri failing to detect cases of undefined behavior in a program.
   This is much less likely with Stacked Borrows.
   Using Tree Borrows currently implies `-Zmiri-strict-provenance` because integer-to-pointer
   casts are not supported in this mode, but that may change in the future.
+* `-Zmiri-tree-borrows-no-precise-interior-mut` makes Tree Borrows
+  track interior mutable data on the level of references instead of on the
+  byte-level as is done by default.  Therefore, with this flag, Tree
+  Borrows will be more permissive.
 * `-Zmiri-force-page-size=<num>` overrides the default page size for an architecture, in multiples of 1k.
   `4` is default for most targets. This value should always be a power of 2 and nonzero.
 
diff --git a/src/tools/miri/cargo-miri/Cargo.lock b/src/tools/miri/cargo-miri/Cargo.lock
index c1915ae617e..d37f8750bde 100644
--- a/src/tools/miri/cargo-miri/Cargo.lock
+++ b/src/tools/miri/cargo-miri/Cargo.lock
@@ -3,6 +3,15 @@
 version = 4
 
 [[package]]
+name = "aho-corasick"
+version = "1.1.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8e60d3430d3a69478ad0993f19238d2df97c507009a52b3c10addcd7f6bcb916"
+dependencies = [
+ "memchr",
+]
+
+[[package]]
 name = "anyhow"
 version = "1.0.97"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -207,12 +216,42 @@ dependencies = [
 ]
 
 [[package]]
+name = "regex"
+version = "1.11.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b544ef1b4eac5dc2db33ea63606ae9ffcfac26c1416a2806ae0bf5f56b201191"
+dependencies = [
+ "aho-corasick",
+ "memchr",
+ "regex-automata",
+ "regex-syntax",
+]
+
+[[package]]
+name = "regex-automata"
+version = "0.4.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "809e8dc61f6de73b46c85f4c96486310fe304c434cfa43669d7b40f711150908"
+dependencies = [
+ "aho-corasick",
+ "memchr",
+ "regex-syntax",
+]
+
+[[package]]
+name = "regex-syntax"
+version = "0.8.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2b15c43186be67a4fd63bee50d0303afffcef381492ebe2c5d87f324e1b8815c"
+
+[[package]]
 name = "rustc-build-sysroot"
-version = "0.5.7"
+version = "0.5.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "10edc2e4393515193bd766e2f6c050b0536a68e56f2b6d56c07ababfdc114ff0"
+checksum = "16d115ad7e26e0d1337f64ae6598f758194696afc2e9f34c8a6f24582529c3dc"
 dependencies = [
  "anyhow",
+ "regex",
  "rustc_version",
  "tempfile",
  "walkdir",
diff --git a/src/tools/miri/cargo-miri/Cargo.toml b/src/tools/miri/cargo-miri/Cargo.toml
index 5c579b2a77d..e08733959cc 100644
--- a/src/tools/miri/cargo-miri/Cargo.toml
+++ b/src/tools/miri/cargo-miri/Cargo.toml
@@ -18,7 +18,7 @@ directories = "6"
 rustc_version = "0.4"
 serde_json = "1.0.40"
 cargo_metadata = "0.19"
-rustc-build-sysroot = "0.5.7"
+rustc-build-sysroot = "0.5.8"
 
 # Enable some feature flags that dev-dependencies need but dependencies
 # do not.  This makes `./miri install` after `./miri build` faster.
diff --git a/src/tools/miri/rust-version b/src/tools/miri/rust-version
index 553d410b2bc..90c6e31e9d1 100644
--- a/src/tools/miri/rust-version
+++ b/src/tools/miri/rust-version
@@ -1 +1 @@
-337c11e5932275e7d450c1f2e26f289f0ddfa717
+0cbc0764380630780a275c437260e4d4d5f28c92
diff --git a/src/tools/miri/src/alloc_addresses/mod.rs b/src/tools/miri/src/alloc_addresses/mod.rs
index 12a320b9676..4a038fe6487 100644
--- a/src/tools/miri/src/alloc_addresses/mod.rs
+++ b/src/tools/miri/src/alloc_addresses/mod.rs
@@ -132,7 +132,7 @@ trait EvalContextExtPriv<'tcx>: crate::MiriInterpCxExt<'tcx> {
         assert!(!matches!(info.kind, AllocKind::Dead));
 
         // This allocation does not have a base address yet, pick or reuse one.
-        if this.machine.native_lib.is_some() {
+        if !this.machine.native_lib.is_empty() {
             // In native lib mode, we use the "real" address of the bytes for this allocation.
             // This ensures the interpreted program and native code have the same view of memory.
             let params = this.machine.get_default_alloc_params();
@@ -413,7 +413,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
     ) -> InterpResult<'tcx, MiriAllocBytes> {
         let this = self.eval_context_ref();
         assert!(this.tcx.try_get_global_alloc(id).is_some());
-        if this.machine.native_lib.is_some() {
+        if !this.machine.native_lib.is_empty() {
             // In native lib mode, MiriAllocBytes for global allocations are handled via `prepared_alloc_bytes`.
             // This additional call ensures that some `MiriAllocBytes` are always prepared, just in case
             // this function gets called before the first time `addr_from_alloc_id` gets called.
diff --git a/src/tools/miri/src/bin/miri.rs b/src/tools/miri/src/bin/miri.rs
index 0121472d330..d4ba7fbd6a4 100644
--- a/src/tools/miri/src/bin/miri.rs
+++ b/src/tools/miri/src/bin/miri.rs
@@ -35,7 +35,7 @@ use std::sync::{Arc, Once};
 
 use miri::{
     BacktraceStyle, BorrowTrackerMethod, GenmcConfig, GenmcCtx, MiriConfig, MiriEntryFnType,
-    ProvenanceMode, RetagFields, ValidationMode,
+    ProvenanceMode, RetagFields, TreeBorrowsParams, ValidationMode,
 };
 use rustc_abi::ExternAbi;
 use rustc_data_structures::sync;
@@ -554,8 +554,21 @@ fn main() {
         } else if arg == "-Zmiri-disable-stacked-borrows" {
             miri_config.borrow_tracker = None;
         } else if arg == "-Zmiri-tree-borrows" {
-            miri_config.borrow_tracker = Some(BorrowTrackerMethod::TreeBorrows);
+            miri_config.borrow_tracker =
+                Some(BorrowTrackerMethod::TreeBorrows(TreeBorrowsParams {
+                    precise_interior_mut: true,
+                }));
             miri_config.provenance_mode = ProvenanceMode::Strict;
+        } else if arg == "-Zmiri-tree-borrows-no-precise-interior-mut" {
+            match &mut miri_config.borrow_tracker {
+                Some(BorrowTrackerMethod::TreeBorrows(params)) => {
+                    params.precise_interior_mut = false;
+                }
+                _ =>
+                    show_error!(
+                        "`-Zmiri-tree-borrows` is required before `-Zmiri-tree-borrows-no-precise-interior-mut`"
+                    ),
+            };
         } else if arg == "-Zmiri-disable-data-race-detector" {
             miri_config.data_race_detector = false;
             miri_config.weak_memory_emulation = false;
@@ -588,6 +601,8 @@ fn main() {
             miri_config.collect_leak_backtraces = false;
         } else if arg == "-Zmiri-force-intrinsic-fallback" {
             miri_config.force_intrinsic_fallback = true;
+        } else if arg == "-Zmiri-deterministic-floats" {
+            miri_config.float_nondet = false;
         } else if arg == "-Zmiri-strict-provenance" {
             miri_config.provenance_mode = ProvenanceMode::Strict;
         } else if arg == "-Zmiri-permissive-provenance" {
@@ -692,11 +707,18 @@ fn main() {
             };
         } else if let Some(param) = arg.strip_prefix("-Zmiri-native-lib=") {
             let filename = param.to_string();
-            if std::path::Path::new(&filename).exists() {
-                if let Some(other_filename) = miri_config.native_lib {
-                    show_error!("-Zmiri-native-lib is already set to {}", other_filename.display());
+            let file_path = std::path::Path::new(&filename);
+            if file_path.exists() {
+                // For directories, nonrecursively add all normal files inside
+                if let Ok(dir) = file_path.read_dir() {
+                    for lib in dir.filter_map(|res| res.ok()) {
+                        if lib.file_type().unwrap().is_file() {
+                            miri_config.native_lib.push(lib.path().to_owned());
+                        }
+                    }
+                } else {
+                    miri_config.native_lib.push(filename.into());
                 }
-                miri_config.native_lib = Some(filename.into());
             } else {
                 show_error!("-Zmiri-native-lib `{}` does not exist", filename);
             }
@@ -725,18 +747,19 @@ fn main() {
         }
     }
     // Tree Borrows implies strict provenance, and is not compatible with native calls.
-    if matches!(miri_config.borrow_tracker, Some(BorrowTrackerMethod::TreeBorrows)) {
+    if matches!(miri_config.borrow_tracker, Some(BorrowTrackerMethod::TreeBorrows { .. })) {
         if miri_config.provenance_mode != ProvenanceMode::Strict {
             show_error!(
                 "Tree Borrows does not support integer-to-pointer casts, and hence requires strict provenance"
             );
         }
-        if miri_config.native_lib.is_some() {
+        if !miri_config.native_lib.is_empty() {
             show_error!("Tree Borrows is not compatible with calling native functions");
         }
     }
+
     // Native calls and strict provenance are not compatible.
-    if miri_config.native_lib.is_some() && miri_config.provenance_mode == ProvenanceMode::Strict {
+    if !miri_config.native_lib.is_empty() && miri_config.provenance_mode == ProvenanceMode::Strict {
         show_error!("strict provenance is not compatible with calling native functions");
     }
     // You can set either one seed or many.
diff --git a/src/tools/miri/src/borrow_tracker/mod.rs b/src/tools/miri/src/borrow_tracker/mod.rs
index b66c561d2b8..36c61053a32 100644
--- a/src/tools/miri/src/borrow_tracker/mod.rs
+++ b/src/tools/miri/src/borrow_tracker/mod.rs
@@ -226,7 +226,13 @@ pub enum BorrowTrackerMethod {
     /// Stacked Borrows, as implemented in borrow_tracker/stacked_borrows
     StackedBorrows,
     /// Tree borrows, as implemented in borrow_tracker/tree_borrows
-    TreeBorrows,
+    TreeBorrows(TreeBorrowsParams),
+}
+
+/// Parameters that Tree Borrows can take.
+#[derive(Debug, Copy, Clone, PartialEq, Eq)]
+pub struct TreeBorrowsParams {
+    pub precise_interior_mut: bool,
 }
 
 impl BorrowTrackerMethod {
@@ -237,6 +243,13 @@ impl BorrowTrackerMethod {
             config.retag_fields,
         ))
     }
+
+    pub fn get_tree_borrows_params(self) -> TreeBorrowsParams {
+        match self {
+            BorrowTrackerMethod::TreeBorrows(params) => params,
+            _ => panic!("can only be called when `BorrowTrackerMethod` is `TreeBorrows`"),
+        }
+    }
 }
 
 impl GlobalStateInner {
@@ -252,7 +265,7 @@ impl GlobalStateInner {
                 AllocState::StackedBorrows(Box::new(RefCell::new(Stacks::new_allocation(
                     id, alloc_size, self, kind, machine,
                 )))),
-            BorrowTrackerMethod::TreeBorrows =>
+            BorrowTrackerMethod::TreeBorrows { .. } =>
                 AllocState::TreeBorrows(Box::new(RefCell::new(Tree::new_allocation(
                     id, alloc_size, self, kind, machine,
                 )))),
@@ -271,7 +284,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
         let method = this.machine.borrow_tracker.as_ref().unwrap().borrow().borrow_tracker_method;
         match method {
             BorrowTrackerMethod::StackedBorrows => this.sb_retag_ptr_value(kind, val),
-            BorrowTrackerMethod::TreeBorrows => this.tb_retag_ptr_value(kind, val),
+            BorrowTrackerMethod::TreeBorrows { .. } => this.tb_retag_ptr_value(kind, val),
         }
     }
 
@@ -284,7 +297,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
         let method = this.machine.borrow_tracker.as_ref().unwrap().borrow().borrow_tracker_method;
         match method {
             BorrowTrackerMethod::StackedBorrows => this.sb_retag_place_contents(kind, place),
-            BorrowTrackerMethod::TreeBorrows => this.tb_retag_place_contents(kind, place),
+            BorrowTrackerMethod::TreeBorrows { .. } => this.tb_retag_place_contents(kind, place),
         }
     }
 
@@ -293,7 +306,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
         let method = this.machine.borrow_tracker.as_ref().unwrap().borrow().borrow_tracker_method;
         match method {
             BorrowTrackerMethod::StackedBorrows => this.sb_protect_place(place),
-            BorrowTrackerMethod::TreeBorrows => this.tb_protect_place(place),
+            BorrowTrackerMethod::TreeBorrows { .. } => this.tb_protect_place(place),
         }
     }
 
@@ -302,7 +315,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
         let method = this.machine.borrow_tracker.as_ref().unwrap().borrow().borrow_tracker_method;
         match method {
             BorrowTrackerMethod::StackedBorrows => this.sb_expose_tag(alloc_id, tag),
-            BorrowTrackerMethod::TreeBorrows => this.tb_expose_tag(alloc_id, tag),
+            BorrowTrackerMethod::TreeBorrows { .. } => this.tb_expose_tag(alloc_id, tag),
         }
     }
 
@@ -319,7 +332,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
                 this.tcx.tcx.dcx().warn("Stacked Borrows does not support named pointers; `miri_pointer_name` is a no-op");
                 interp_ok(())
             }
-            BorrowTrackerMethod::TreeBorrows =>
+            BorrowTrackerMethod::TreeBorrows { .. } =>
                 this.tb_give_pointer_debug_name(ptr, nth_parent, name),
         }
     }
@@ -333,7 +346,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
         let method = borrow_tracker.borrow().borrow_tracker_method;
         match method {
             BorrowTrackerMethod::StackedBorrows => this.print_stacks(alloc_id),
-            BorrowTrackerMethod::TreeBorrows => this.print_tree(alloc_id, show_unnamed),
+            BorrowTrackerMethod::TreeBorrows { .. } => this.print_tree(alloc_id, show_unnamed),
         }
     }
 
diff --git a/src/tools/miri/src/borrow_tracker/tree_borrows/mod.rs b/src/tools/miri/src/borrow_tracker/tree_borrows/mod.rs
index 411ae89da90..ce8fe03ee47 100644
--- a/src/tools/miri/src/borrow_tracker/tree_borrows/mod.rs
+++ b/src/tools/miri/src/borrow_tracker/tree_borrows/mod.rs
@@ -312,8 +312,6 @@ trait EvalContextPrivExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
         }
 
         let span = this.machine.current_span();
-        let alloc_extra = this.get_alloc_extra(alloc_id)?;
-        let mut tree_borrows = alloc_extra.borrow_tracker_tb().borrow_mut();
 
         // Store initial permissions and their corresponding range.
         let mut perms_map: RangeMap<LocationState> = RangeMap::new(
@@ -342,36 +340,83 @@ trait EvalContextPrivExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
         assert!(new_perm.freeze_access);
 
         let protected = new_perm.protector.is_some();
-        this.visit_freeze_sensitive(place, ptr_size, |range, frozen| {
-            has_unsafe_cell = has_unsafe_cell || !frozen;
-
-            // We are only ever `Frozen` inside the frozen bits.
-            let (perm, access) = if frozen {
+        let precise_interior_mut = this
+            .machine
+            .borrow_tracker
+            .as_mut()
+            .unwrap()
+            .get_mut()
+            .borrow_tracker_method
+            .get_tree_borrows_params()
+            .precise_interior_mut;
+
+        let default_perm = if !precise_interior_mut {
+            // NOTE: Using `ty_is_freeze` doesn't give the same result as going through the range
+            // and computing `has_unsafe_cell`.  This is because of zero-sized `UnsafeCell`, for which
+            // `has_unsafe_cell` is false, but `!ty_is_freeze` is true.
+            let ty_is_freeze = place.layout.ty.is_freeze(*this.tcx, this.typing_env());
+            let (perm, access) = if ty_is_freeze {
                 (new_perm.freeze_perm, new_perm.freeze_access)
             } else {
                 (new_perm.nonfreeze_perm, new_perm.nonfreeze_access)
             };
+            let sifa = perm.strongest_idempotent_foreign_access(protected);
+            let new_loc = if access {
+                LocationState::new_accessed(perm, sifa)
+            } else {
+                LocationState::new_non_accessed(perm, sifa)
+            };
+
+            for (_loc_range, loc) in perms_map.iter_mut_all() {
+                *loc = new_loc;
+            }
+
+            perm
+        } else {
+            this.visit_freeze_sensitive(place, ptr_size, |range, frozen| {
+                has_unsafe_cell = has_unsafe_cell || !frozen;
 
-            // Store initial permissions.
-            for (_loc_range, loc) in perms_map.iter_mut(range.start, range.size) {
+                // We are only ever `Frozen` inside the frozen bits.
+                let (perm, access) = if frozen {
+                    (new_perm.freeze_perm, new_perm.freeze_access)
+                } else {
+                    (new_perm.nonfreeze_perm, new_perm.nonfreeze_access)
+                };
                 let sifa = perm.strongest_idempotent_foreign_access(protected);
                 // NOTE: Currently, `access` is false if and only if `perm` is Cell, so this `if`
                 // doesn't not change whether any code is UB or not. We could just always use
                 // `new_accessed` and everything would stay the same. But that seems conceptually
                 // odd, so we keep the initial "accessed" bit of the `LocationState` in sync with whether
                 // a read access is performed below.
-                if access {
-                    *loc = LocationState::new_accessed(perm, sifa);
+                let new_loc = if access {
+                    LocationState::new_accessed(perm, sifa)
                 } else {
-                    *loc = LocationState::new_non_accessed(perm, sifa);
+                    LocationState::new_non_accessed(perm, sifa)
+                };
+
+                // Store initial permissions.
+                for (_loc_range, loc) in perms_map.iter_mut(range.start, range.size) {
+                    *loc = new_loc;
                 }
-            }
 
-            // Some reborrows incur a read access to the parent.
-            if access {
+                interp_ok(())
+            })?;
+
+            // Allow lazily writing to surrounding data if we found an `UnsafeCell`.
+            if has_unsafe_cell { new_perm.nonfreeze_perm } else { new_perm.freeze_perm }
+        };
+
+        let alloc_extra = this.get_alloc_extra(alloc_id)?;
+        let mut tree_borrows = alloc_extra.borrow_tracker_tb().borrow_mut();
+
+        for (perm_range, perm) in perms_map.iter_mut_all() {
+            if perm.is_accessed() {
+                // Some reborrows incur a read access to the parent.
                 // Adjust range to be relative to allocation start (rather than to `place`).
-                let mut range_in_alloc = range;
-                range_in_alloc.start += base_offset;
+                let range_in_alloc = AllocRange {
+                    start: Size::from_bytes(perm_range.start) + base_offset,
+                    size: Size::from_bytes(perm_range.end - perm_range.start),
+                };
 
                 tree_borrows.perform_access(
                     orig_tag,
@@ -382,7 +427,7 @@ trait EvalContextPrivExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
                 )?;
 
                 // Also inform the data race model (but only if any bytes are actually affected).
-                if range.size.bytes() > 0 {
+                if range_in_alloc.size.bytes() > 0 {
                     if let Some(data_race) = alloc_extra.data_race.as_vclocks_ref() {
                         data_race.read(
                             alloc_id,
@@ -394,8 +439,7 @@ trait EvalContextPrivExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
                     }
                 }
             }
-            interp_ok(())
-        })?;
+        }
 
         // Record the parent-child pair in the tree.
         tree_borrows.new_child(
@@ -403,8 +447,7 @@ trait EvalContextPrivExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
             orig_tag,
             new_tag,
             perms_map,
-            // Allow lazily writing to surrounding data if we found an `UnsafeCell`.
-            if has_unsafe_cell { new_perm.nonfreeze_perm } else { new_perm.freeze_perm },
+            default_perm,
             protected,
             span,
         )?;
diff --git a/src/tools/miri/src/concurrency/sync.rs b/src/tools/miri/src/concurrency/sync.rs
index 64f34d3e21c..74379d6438d 100644
--- a/src/tools/miri/src/concurrency/sync.rs
+++ b/src/tools/miri/src/concurrency/sync.rs
@@ -67,6 +67,11 @@ impl MutexRef {
     fn new() -> Self {
         MutexRef(Rc::new(RefCell::new(Mutex::default())))
     }
+
+    /// Get the id of the thread that currently owns this lock, or `None` if it is not locked.
+    pub fn owner(&self) -> Option<ThreadId> {
+        self.0.borrow().owner
+    }
 }
 
 impl VisitProvenance for MutexRef {
@@ -75,8 +80,6 @@ impl VisitProvenance for MutexRef {
     }
 }
 
-declare_id!(RwLockId);
-
 /// The read-write lock state.
 #[derive(Default, Debug)]
 struct RwLock {
@@ -111,6 +114,49 @@ struct RwLock {
     clock_current_readers: VClock,
 }
 
+impl RwLock {
+    #[inline]
+    /// Check if locked.
+    fn is_locked(&self) -> bool {
+        trace!(
+            "rwlock_is_locked: writer is {:?} and there are {} reader threads (some of which could hold multiple read locks)",
+            self.writer,
+            self.readers.len(),
+        );
+        self.writer.is_some() || self.readers.is_empty().not()
+    }
+
+    /// Check if write locked.
+    #[inline]
+    fn is_write_locked(&self) -> bool {
+        trace!("rwlock_is_write_locked: writer is {:?}", self.writer);
+        self.writer.is_some()
+    }
+}
+
+#[derive(Default, Clone, Debug)]
+pub struct RwLockRef(Rc<RefCell<RwLock>>);
+
+impl RwLockRef {
+    fn new() -> Self {
+        RwLockRef(Rc::new(RefCell::new(RwLock::default())))
+    }
+
+    pub fn is_locked(&self) -> bool {
+        self.0.borrow().is_locked()
+    }
+
+    pub fn is_write_locked(&self) -> bool {
+        self.0.borrow().is_write_locked()
+    }
+}
+
+impl VisitProvenance for RwLockRef {
+    fn visit_provenance(&self, _visit: &mut VisitWith<'_>) {
+        // RwLockRef contains no provenance.
+    }
+}
+
 declare_id!(CondvarId);
 
 /// The conditional variable state.
@@ -164,7 +210,6 @@ struct FutexWaiter {
 /// The state of all synchronization objects.
 #[derive(Default, Debug)]
 pub struct SynchronizationObjects {
-    rwlocks: IndexVec<RwLockId, RwLock>,
     condvars: IndexVec<CondvarId, Condvar>,
     pub(super) init_onces: IndexVec<InitOnceId, InitOnce>,
 }
@@ -174,17 +219,17 @@ impl<'tcx> EvalContextExtPriv<'tcx> for crate::MiriInterpCx<'tcx> {}
 pub(super) trait EvalContextExtPriv<'tcx>: crate::MiriInterpCxExt<'tcx> {
     fn condvar_reacquire_mutex(
         &mut self,
-        mutex_ref: &MutexRef,
+        mutex_ref: MutexRef,
         retval: Scalar,
         dest: MPlaceTy<'tcx>,
     ) -> InterpResult<'tcx> {
         let this = self.eval_context_mut();
-        if this.mutex_is_locked(mutex_ref) {
-            assert_ne!(this.mutex_get_owner(mutex_ref), this.active_thread());
+        if let Some(owner) = mutex_ref.owner() {
+            assert_ne!(owner, this.active_thread());
             this.mutex_enqueue_and_block(mutex_ref, Some((retval, dest)));
         } else {
             // We can have it right now!
-            this.mutex_lock(mutex_ref);
+            this.mutex_lock(&mutex_ref);
             // Don't forget to write the return value.
             this.write_scalar(retval, &dest)?;
         }
@@ -196,8 +241,8 @@ impl SynchronizationObjects {
     pub fn mutex_create(&mut self) -> MutexRef {
         MutexRef::new()
     }
-    pub fn rwlock_create(&mut self) -> RwLockId {
-        self.rwlocks.push(Default::default())
+    pub fn rwlock_create(&mut self) -> RwLockRef {
+        RwLockRef::new()
     }
 
     pub fn condvar_create(&mut self) -> CondvarId {
@@ -334,18 +379,6 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
         Some(alloc_extra.get_sync::<T>(offset).unwrap())
     }
 
-    #[inline]
-    /// Get the id of the thread that currently owns this lock.
-    fn mutex_get_owner(&self, mutex_ref: &MutexRef) -> ThreadId {
-        mutex_ref.0.borrow().owner.unwrap()
-    }
-
-    #[inline]
-    /// Check if locked.
-    fn mutex_is_locked(&self, mutex_ref: &MutexRef) -> bool {
-        mutex_ref.0.borrow().owner.is_some()
-    }
-
     /// Lock by setting the mutex owner and increasing the lock count.
     fn mutex_lock(&mut self, mutex_ref: &MutexRef) {
         let this = self.eval_context_mut();
@@ -413,14 +446,15 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
     #[inline]
     fn mutex_enqueue_and_block(
         &mut self,
-        mutex_ref: &MutexRef,
+        mutex_ref: MutexRef,
         retval_dest: Option<(Scalar, MPlaceTy<'tcx>)>,
     ) {
         let this = self.eval_context_mut();
-        assert!(this.mutex_is_locked(mutex_ref), "queuing on unlocked mutex");
         let thread = this.active_thread();
-        mutex_ref.0.borrow_mut().queue.push_back(thread);
-        let mutex_ref = mutex_ref.clone();
+        let mut mutex = mutex_ref.0.borrow_mut();
+        mutex.queue.push_back(thread);
+        assert!(mutex.owner.is_some(), "queuing on unlocked mutex");
+        drop(mutex);
         this.block_thread(
             BlockReason::Mutex,
             None,
@@ -432,7 +466,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
                 |this, unblock: UnblockKind| {
                     assert_eq!(unblock, UnblockKind::Ready);
 
-                    assert!(!this.mutex_is_locked(&mutex_ref));
+                    assert!(mutex_ref.owner().is_none());
                     this.mutex_lock(&mutex_ref);
 
                     if let Some((retval, dest)) = retval_dest {
@@ -445,37 +479,14 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
         );
     }
 
-    #[inline]
-    /// Check if locked.
-    fn rwlock_is_locked(&self, id: RwLockId) -> bool {
-        let this = self.eval_context_ref();
-        let rwlock = &this.machine.sync.rwlocks[id];
-        trace!(
-            "rwlock_is_locked: {:?} writer is {:?} and there are {} reader threads (some of which could hold multiple read locks)",
-            id,
-            rwlock.writer,
-            rwlock.readers.len(),
-        );
-        rwlock.writer.is_some() || rwlock.readers.is_empty().not()
-    }
-
-    /// Check if write locked.
-    #[inline]
-    fn rwlock_is_write_locked(&self, id: RwLockId) -> bool {
-        let this = self.eval_context_ref();
-        let rwlock = &this.machine.sync.rwlocks[id];
-        trace!("rwlock_is_write_locked: {:?} writer is {:?}", id, rwlock.writer);
-        rwlock.writer.is_some()
-    }
-
     /// Read-lock the lock by adding the `reader` the list of threads that own
     /// this lock.
-    fn rwlock_reader_lock(&mut self, id: RwLockId) {
+    fn rwlock_reader_lock(&mut self, rwlock_ref: &RwLockRef) {
         let this = self.eval_context_mut();
         let thread = this.active_thread();
-        assert!(!this.rwlock_is_write_locked(id), "the lock is write locked");
-        trace!("rwlock_reader_lock: {:?} now also held (one more time) by {:?}", id, thread);
-        let rwlock = &mut this.machine.sync.rwlocks[id];
+        trace!("rwlock_reader_lock: now also held (one more time) by {:?}", thread);
+        let mut rwlock = rwlock_ref.0.borrow_mut();
+        assert!(!rwlock.is_write_locked(), "the lock is write locked");
         let count = rwlock.readers.entry(thread).or_insert(0);
         *count = count.strict_add(1);
         if let Some(data_race) = this.machine.data_race.as_vclocks_ref() {
@@ -485,20 +496,20 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
 
     /// Try read-unlock the lock for the current threads and potentially give the lock to a new owner.
     /// Returns `true` if succeeded, `false` if this `reader` did not hold the lock.
-    fn rwlock_reader_unlock(&mut self, id: RwLockId) -> InterpResult<'tcx, bool> {
+    fn rwlock_reader_unlock(&mut self, rwlock_ref: &RwLockRef) -> InterpResult<'tcx, bool> {
         let this = self.eval_context_mut();
         let thread = this.active_thread();
-        let rwlock = &mut this.machine.sync.rwlocks[id];
+        let mut rwlock = rwlock_ref.0.borrow_mut();
         match rwlock.readers.entry(thread) {
             Entry::Occupied(mut entry) => {
                 let count = entry.get_mut();
                 assert!(*count > 0, "rwlock locked with count == 0");
                 *count -= 1;
                 if *count == 0 {
-                    trace!("rwlock_reader_unlock: {:?} no longer held by {:?}", id, thread);
+                    trace!("rwlock_reader_unlock: no longer held by {:?}", thread);
                     entry.remove();
                 } else {
-                    trace!("rwlock_reader_unlock: {:?} held one less time by {:?}", id, thread);
+                    trace!("rwlock_reader_unlock: held one less time by {:?}", thread);
                 }
             }
             Entry::Vacant(_) => return interp_ok(false), // we did not even own this lock
@@ -511,15 +522,16 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
         }
 
         // The thread was a reader. If the lock is not held any more, give it to a writer.
-        if this.rwlock_is_locked(id).not() {
+        if rwlock.is_locked().not() {
             // All the readers are finished, so set the writer data-race handle to the value
             // of the union of all reader data race handles, since the set of readers
             // happen-before the writers
-            let rwlock = &mut this.machine.sync.rwlocks[id];
-            rwlock.clock_unlocked.clone_from(&rwlock.clock_current_readers);
+            let rwlock_ref = &mut *rwlock;
+            rwlock_ref.clock_unlocked.clone_from(&rwlock_ref.clock_current_readers);
             // See if there is a thread to unblock.
-            if let Some(writer) = rwlock.writer_queue.pop_front() {
-                this.unblock_thread(writer, BlockReason::RwLock(id))?;
+            if let Some(writer) = rwlock_ref.writer_queue.pop_front() {
+                drop(rwlock); // make RefCell available for unblock callback
+                this.unblock_thread(writer, BlockReason::RwLock)?;
             }
         }
         interp_ok(true)
@@ -530,26 +542,28 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
     #[inline]
     fn rwlock_enqueue_and_block_reader(
         &mut self,
-        id: RwLockId,
+        rwlock_ref: RwLockRef,
         retval: Scalar,
         dest: MPlaceTy<'tcx>,
     ) {
         let this = self.eval_context_mut();
         let thread = this.active_thread();
-        assert!(this.rwlock_is_write_locked(id), "read-queueing on not write locked rwlock");
-        this.machine.sync.rwlocks[id].reader_queue.push_back(thread);
+        let mut rwlock = rwlock_ref.0.borrow_mut();
+        rwlock.reader_queue.push_back(thread);
+        assert!(rwlock.is_write_locked(), "read-queueing on not write locked rwlock");
+        drop(rwlock);
         this.block_thread(
-            BlockReason::RwLock(id),
+            BlockReason::RwLock,
             None,
             callback!(
                 @capture<'tcx> {
-                    id: RwLockId,
+                    rwlock_ref: RwLockRef,
                     retval: Scalar,
                     dest: MPlaceTy<'tcx>,
                 }
                 |this, unblock: UnblockKind| {
                     assert_eq!(unblock, UnblockKind::Ready);
-                    this.rwlock_reader_lock(id);
+                    this.rwlock_reader_lock(&rwlock_ref);
                     this.write_scalar(retval, &dest)?;
                     interp_ok(())
                 }
@@ -559,12 +573,13 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
 
     /// Lock by setting the writer that owns the lock.
     #[inline]
-    fn rwlock_writer_lock(&mut self, id: RwLockId) {
+    fn rwlock_writer_lock(&mut self, rwlock_ref: &RwLockRef) {
         let this = self.eval_context_mut();
         let thread = this.active_thread();
-        assert!(!this.rwlock_is_locked(id), "the rwlock is already locked");
-        trace!("rwlock_writer_lock: {:?} now held by {:?}", id, thread);
-        let rwlock = &mut this.machine.sync.rwlocks[id];
+        trace!("rwlock_writer_lock: now held by {:?}", thread);
+
+        let mut rwlock = rwlock_ref.0.borrow_mut();
+        assert!(!rwlock.is_locked(), "the rwlock is already locked");
         rwlock.writer = Some(thread);
         if let Some(data_race) = this.machine.data_race.as_vclocks_ref() {
             data_race.acquire_clock(&rwlock.clock_unlocked, &this.machine.threads);
@@ -574,35 +589,38 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
     /// Try to unlock an rwlock held by the current thread.
     /// Return `false` if it is held by another thread.
     #[inline]
-    fn rwlock_writer_unlock(&mut self, id: RwLockId) -> InterpResult<'tcx, bool> {
+    fn rwlock_writer_unlock(&mut self, rwlock_ref: &RwLockRef) -> InterpResult<'tcx, bool> {
         let this = self.eval_context_mut();
         let thread = this.active_thread();
-        let rwlock = &mut this.machine.sync.rwlocks[id];
+        let mut rwlock = rwlock_ref.0.borrow_mut();
         interp_ok(if let Some(current_writer) = rwlock.writer {
             if current_writer != thread {
                 // Only the owner can unlock the rwlock.
                 return interp_ok(false);
             }
             rwlock.writer = None;
-            trace!("rwlock_writer_unlock: {:?} unlocked by {:?}", id, thread);
+            trace!("rwlock_writer_unlock: unlocked by {:?}", thread);
             // Record release clock for next lock holder.
             if let Some(data_race) = this.machine.data_race.as_vclocks_ref() {
                 data_race.release_clock(&this.machine.threads, |clock| {
                     rwlock.clock_unlocked.clone_from(clock)
                 });
             }
+
             // The thread was a writer.
             //
             // We are prioritizing writers here against the readers. As a
             // result, not only readers can starve writers, but also writers can
             // starve readers.
             if let Some(writer) = rwlock.writer_queue.pop_front() {
-                this.unblock_thread(writer, BlockReason::RwLock(id))?;
+                drop(rwlock); // make RefCell available for unblock callback
+                this.unblock_thread(writer, BlockReason::RwLock)?;
             } else {
                 // Take the entire read queue and wake them all up.
                 let readers = std::mem::take(&mut rwlock.reader_queue);
+                drop(rwlock); // make RefCell available for unblock callback
                 for reader in readers {
-                    this.unblock_thread(reader, BlockReason::RwLock(id))?;
+                    this.unblock_thread(reader, BlockReason::RwLock)?;
                 }
             }
             true
@@ -616,26 +634,28 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
     #[inline]
     fn rwlock_enqueue_and_block_writer(
         &mut self,
-        id: RwLockId,
+        rwlock_ref: RwLockRef,
         retval: Scalar,
         dest: MPlaceTy<'tcx>,
     ) {
         let this = self.eval_context_mut();
-        assert!(this.rwlock_is_locked(id), "write-queueing on unlocked rwlock");
         let thread = this.active_thread();
-        this.machine.sync.rwlocks[id].writer_queue.push_back(thread);
+        let mut rwlock = rwlock_ref.0.borrow_mut();
+        rwlock.writer_queue.push_back(thread);
+        assert!(rwlock.is_locked(), "write-queueing on unlocked rwlock");
+        drop(rwlock);
         this.block_thread(
-            BlockReason::RwLock(id),
+            BlockReason::RwLock,
             None,
             callback!(
                 @capture<'tcx> {
-                    id: RwLockId,
+                    rwlock_ref: RwLockRef,
                     retval: Scalar,
                     dest: MPlaceTy<'tcx>,
                 }
                 |this, unblock: UnblockKind| {
                     assert_eq!(unblock, UnblockKind::Ready);
-                    this.rwlock_writer_lock(id);
+                    this.rwlock_writer_lock(&rwlock_ref);
                     this.write_scalar(retval, &dest)?;
                     interp_ok(())
                 }
@@ -700,7 +720,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
                             }
                             // Try to acquire the mutex.
                             // The timeout only applies to the first wait (until the signal), not for mutex acquisition.
-                            this.condvar_reacquire_mutex(&mutex_ref, retval_succ, dest)
+                            this.condvar_reacquire_mutex(mutex_ref, retval_succ, dest)
                         }
                         UnblockKind::TimedOut => {
                             // We have to remove the waiter from the queue again.
@@ -708,7 +728,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
                             let waiters = &mut this.machine.sync.condvars[condvar].waiters;
                             waiters.retain(|waiter| *waiter != thread);
                             // Now get back the lock.
-                            this.condvar_reacquire_mutex(&mutex_ref, retval_timeout, dest)
+                            this.condvar_reacquire_mutex(mutex_ref, retval_timeout, dest)
                         }
                     }
                 }
diff --git a/src/tools/miri/src/concurrency/thread.rs b/src/tools/miri/src/concurrency/thread.rs
index ba1436b77b8..38b5d4c0f06 100644
--- a/src/tools/miri/src/concurrency/thread.rs
+++ b/src/tools/miri/src/concurrency/thread.rs
@@ -99,7 +99,7 @@ pub enum BlockReason {
     /// Blocked on a condition variable.
     Condvar(CondvarId),
     /// Blocked on a reader-writer lock.
-    RwLock(RwLockId),
+    RwLock,
     /// Blocked on a Futex variable.
     Futex,
     /// Blocked on an InitOnce.
diff --git a/src/tools/miri/src/diagnostics.rs b/src/tools/miri/src/diagnostics.rs
index 1728a9cfd6d..54a7c1407ea 100644
--- a/src/tools/miri/src/diagnostics.rs
+++ b/src/tools/miri/src/diagnostics.rs
@@ -85,7 +85,7 @@ impl fmt::Display for TerminationInfo {
             DataRace { involves_non_atomic, ptr, op1, op2, .. } =>
                 write!(
                     f,
-                    "{} detected between (1) {} on {} and (2) {} on {} at {ptr:?}. (2) just happened here",
+                    "{} detected between (1) {} on {} and (2) {} on {} at {ptr:?}",
                     if *involves_non_atomic { "Data race" } else { "Race condition" },
                     op1.action,
                     op1.thread_info,
@@ -224,7 +224,7 @@ pub fn report_error<'tcx>(
     use InterpErrorKind::*;
     use UndefinedBehaviorInfo::*;
 
-    let mut msg = vec![];
+    let mut labels = vec![];
 
     let (title, helps) = if let MachineStop(info) = e.kind() {
         let info = info.downcast_ref::<TerminationInfo>().expect("invalid MachineStop payload");
@@ -237,7 +237,10 @@ pub fn report_error<'tcx>(
                 Some("unsupported operation"),
             StackedBorrowsUb { .. } | TreeBorrowsUb { .. } | DataRace { .. } =>
                 Some("Undefined Behavior"),
-            Deadlock => Some("deadlock"),
+            Deadlock => {
+                labels.push(format!("this thread got stuck here"));
+                None
+            }
             GenmcStuckExecution => {
                 // This case should only happen in GenMC mode. We treat it like a normal program exit.
                 assert!(ecx.machine.data_race.as_genmc_ref().is_some());
@@ -259,7 +262,7 @@ pub fn report_error<'tcx>(
                 ]
             }
             StackedBorrowsUb { help, history, .. } => {
-                msg.extend(help.clone());
+                labels.extend(help.clone());
                 let mut helps = vec![
                     note!("this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental"),
                     note!("see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information"),
@@ -297,6 +300,7 @@ pub fn report_error<'tcx>(
             Int2PtrWithStrictProvenance =>
                 vec![note!("use Strict Provenance APIs (https://doc.rust-lang.org/nightly/std/ptr/index.html#strict-provenance, https://crates.io/crates/sptr) instead")],
             DataRace { op1, extra, retag_explain, .. } => {
+                labels.push(format!("(2) just happened here"));
                 let mut helps = vec![note_span!(op1.span, "and (1) occurred earlier here")];
                 if let Some(extra) = extra {
                     helps.push(note!("{extra}"));
@@ -426,12 +430,20 @@ pub fn report_error<'tcx>(
         _ => {}
     }
 
-    msg.insert(0, format_interp_error(ecx.tcx.dcx(), e));
+    let mut primary_msg = String::new();
+    if let Some(title) = title {
+        write!(primary_msg, "{title}: ").unwrap();
+    }
+    write!(primary_msg, "{}", format_interp_error(ecx.tcx.dcx(), e)).unwrap();
+
+    if labels.is_empty() {
+        labels.push(format!("{} occurred here", title.unwrap_or("error")));
+    }
 
     report_msg(
         DiagLevel::Error,
-        if let Some(title) = title { format!("{title}: {}", msg[0]) } else { msg[0].clone() },
-        msg,
+        primary_msg,
+        labels,
         vec![],
         helps,
         &stacktrace,
@@ -449,8 +461,8 @@ pub fn report_error<'tcx>(
                 any_pruned |= was_pruned;
                 report_msg(
                     DiagLevel::Error,
-                    format!("deadlock: the evaluated program deadlocked"),
-                    vec![format!("the evaluated program deadlocked")],
+                    format!("the evaluated program deadlocked"),
+                    vec![format!("this thread got stuck here")],
                     vec![],
                     vec![],
                     &stacktrace,
@@ -611,7 +623,7 @@ impl<'tcx> MiriMachine<'tcx> {
         let stacktrace = Frame::generate_stacktrace_from_stack(self.threads.active_thread_stack());
         let (stacktrace, _was_pruned) = prune_stacktrace(stacktrace, self);
 
-        let (title, diag_level) = match &e {
+        let (label, diag_level) = match &e {
             RejectedIsolatedOp(_) =>
                 ("operation rejected by isolation".to_string(), DiagLevel::Warning),
             Int2Ptr { .. } => ("integer-to-pointer cast".to_string(), DiagLevel::Warning),
@@ -626,10 +638,10 @@ impl<'tcx> MiriMachine<'tcx> {
             | FreedAlloc(..)
             | ProgressReport { .. }
             | WeakMemoryOutdatedLoad { .. } =>
-                ("tracking was triggered".to_string(), DiagLevel::Note),
+                ("tracking was triggered here".to_string(), DiagLevel::Note),
         };
 
-        let msg = match &e {
+        let title = match &e {
             CreatedPointerTag(tag, None, _) => format!("created base tag {tag:?}"),
             CreatedPointerTag(tag, Some(perm), None) =>
                 format!("created {tag:?} with {perm} derived from unknown tag"),
@@ -682,7 +694,10 @@ impl<'tcx> MiriMachine<'tcx> {
                     ),
                 ];
                 if self.borrow_tracker.as_ref().is_some_and(|b| {
-                    matches!(b.borrow().borrow_tracker_method(), BorrowTrackerMethod::TreeBorrows)
+                    matches!(
+                        b.borrow().borrow_tracker_method(),
+                        BorrowTrackerMethod::TreeBorrows { .. }
+                    )
                 }) {
                     v.push(
                         note!("Tree Borrows does not support integer-to-pointer casts, so the program is likely to go wrong when this pointer gets used")
@@ -732,7 +747,7 @@ impl<'tcx> MiriMachine<'tcx> {
         report_msg(
             diag_level,
             title,
-            vec![msg],
+            vec![label],
             notes,
             helps,
             &stacktrace,
diff --git a/src/tools/miri/src/eval.rs b/src/tools/miri/src/eval.rs
index 5880e5fbc37..7a5f96ec177 100644
--- a/src/tools/miri/src/eval.rs
+++ b/src/tools/miri/src/eval.rs
@@ -148,9 +148,8 @@ pub struct MiriConfig {
     pub report_progress: Option<u32>,
     /// Whether Stacked Borrows and Tree Borrows retagging should recurse into fields of datatypes.
     pub retag_fields: RetagFields,
-    /// The location of a shared object file to load when calling external functions
-    /// FIXME! consider allowing users to specify paths to multiple files, or to a directory
-    pub native_lib: Option<PathBuf>,
+    /// The location of the shared object files to load when calling external functions
+    pub native_lib: Vec<PathBuf>,
     /// Run a garbage collector for BorTags every N basic blocks.
     pub gc_interval: u32,
     /// The number of CPUs to be reported by miri.
@@ -167,6 +166,8 @@ pub struct MiriConfig {
     pub fixed_scheduling: bool,
     /// Always prefer the intrinsic fallback body over the native Miri implementation.
     pub force_intrinsic_fallback: bool,
+    /// Whether floating-point operations can behave non-deterministically.
+    pub float_nondet: bool,
 }
 
 impl Default for MiriConfig {
@@ -197,7 +198,7 @@ impl Default for MiriConfig {
             preemption_rate: 0.01, // 1%
             report_progress: None,
             retag_fields: RetagFields::Yes,
-            native_lib: None,
+            native_lib: vec![],
             gc_interval: 10_000,
             num_cpus: 1,
             page_size: None,
@@ -206,6 +207,7 @@ impl Default for MiriConfig {
             address_reuse_cross_thread_rate: 0.1,
             fixed_scheduling: false,
             force_intrinsic_fallback: false,
+            float_nondet: true,
         }
     }
 }
diff --git a/src/tools/miri/src/intrinsics/mod.rs b/src/tools/miri/src/intrinsics/mod.rs
index a4882a20148..ec77a162cdb 100644
--- a/src/tools/miri/src/intrinsics/mod.rs
+++ b/src/tools/miri/src/intrinsics/mod.rs
@@ -3,17 +3,20 @@
 mod atomic;
 mod simd;
 
+use std::ops::Neg;
+
 use rand::Rng;
 use rustc_abi::Size;
-use rustc_apfloat::{Float, Round};
+use rustc_apfloat::ieee::{IeeeFloat, Semantics};
+use rustc_apfloat::{self, Float, Round};
 use rustc_middle::mir;
-use rustc_middle::ty::{self, FloatTy};
+use rustc_middle::ty::{self, FloatTy, ScalarInt};
 use rustc_span::{Symbol, sym};
 
 use self::atomic::EvalContextExt as _;
 use self::helpers::{ToHost, ToSoft, check_intrinsic_arg_count};
 use self::simd::EvalContextExt as _;
-use crate::math::apply_random_float_error_to_imm;
+use crate::math::{IeeeExt, apply_random_float_error_ulp};
 use crate::*;
 
 impl<'tcx> EvalContextExt<'tcx> for crate::MiriInterpCx<'tcx> {}
@@ -187,31 +190,39 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
             => {
                 let [f] = check_intrinsic_arg_count(args)?;
                 let f = this.read_scalar(f)?.to_f32()?;
-                // Using host floats (but it's fine, these operations do not have
-                // guaranteed precision).
-                let host = f.to_host();
-                let res = match intrinsic_name {
-                    "sinf32" => host.sin(),
-                    "cosf32" => host.cos(),
-                    "expf32" => host.exp(),
-                    "exp2f32" => host.exp2(),
-                    "logf32" => host.ln(),
-                    "log10f32" => host.log10(),
-                    "log2f32" => host.log2(),
-                    _ => bug!(),
-                };
-                let res = res.to_soft();
-                // Apply a relative error of 16ULP to introduce some non-determinism
-                // simulating imprecise implementations and optimizations.
-                // FIXME: temporarily disabled as it breaks std tests.
-                // let res = apply_random_float_error_ulp(
-                //     this,
-                //     res,
-                //     4, // log2(16)
-                // );
+
+                let res = fixed_float_value(intrinsic_name, &[f]).unwrap_or_else(||{
+                    // Using host floats (but it's fine, these operations do not have
+                    // guaranteed precision).
+                    let host = f.to_host();
+                    let res = match intrinsic_name {
+                        "sinf32" => host.sin(),
+                        "cosf32" => host.cos(),
+                        "expf32" => host.exp(),
+                        "exp2f32" => host.exp2(),
+                        "logf32" => host.ln(),
+                        "log10f32" => host.log10(),
+                        "log2f32" => host.log2(),
+                        _ => bug!(),
+                    };
+                    let res = res.to_soft();
+
+                    // Apply a relative error of 4ULP to introduce some non-determinism
+                    // simulating imprecise implementations and optimizations.
+                    let res = apply_random_float_error_ulp(
+                        this,
+                        res,
+                        2, // log2(4)
+                    );
+
+                    // Clamp the result to the guaranteed range of this function according to the C standard,
+                    // if any.
+                    clamp_float_value(intrinsic_name, res)
+                });
                 let res = this.adjust_nan(res, &[f]);
                 this.write_scalar(res, dest)?;
             }
+
             #[rustfmt::skip]
             | "sinf64"
             | "cosf64"
@@ -223,28 +234,35 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
             => {
                 let [f] = check_intrinsic_arg_count(args)?;
                 let f = this.read_scalar(f)?.to_f64()?;
-                // Using host floats (but it's fine, these operations do not have
-                // guaranteed precision).
-                let host = f.to_host();
-                let res = match intrinsic_name {
-                    "sinf64" => host.sin(),
-                    "cosf64" => host.cos(),
-                    "expf64" => host.exp(),
-                    "exp2f64" => host.exp2(),
-                    "logf64" => host.ln(),
-                    "log10f64" => host.log10(),
-                    "log2f64" => host.log2(),
-                    _ => bug!(),
-                };
-                let res = res.to_soft();
-                // Apply a relative error of 16ULP to introduce some non-determinism
-                // simulating imprecise implementations and optimizations.
-                // FIXME: temporarily disabled as it breaks std tests.
-                // let res = apply_random_float_error_ulp(
-                //     this,
-                //     res,
-                //     4, // log2(16)
-                // );
+
+                let res = fixed_float_value(intrinsic_name, &[f]).unwrap_or_else(||{
+                    // Using host floats (but it's fine, these operations do not have
+                    // guaranteed precision).
+                    let host = f.to_host();
+                    let res = match intrinsic_name {
+                        "sinf64" => host.sin(),
+                        "cosf64" => host.cos(),
+                        "expf64" => host.exp(),
+                        "exp2f64" => host.exp2(),
+                        "logf64" => host.ln(),
+                        "log10f64" => host.log10(),
+                        "log2f64" => host.log2(),
+                        _ => bug!(),
+                    };
+                    let res = res.to_soft();
+
+                    // Apply a relative error of 4ULP to introduce some non-determinism
+                    // simulating imprecise implementations and optimizations.
+                    let res = apply_random_float_error_ulp(
+                        this,
+                        res,
+                        2, // log2(4)
+                    );
+
+                    // Clamp the result to the guaranteed range of this function according to the C standard,
+                    // if any.
+                    clamp_float_value(intrinsic_name, res)
+                });
                 let res = this.adjust_nan(res, &[f]);
                 this.write_scalar(res, dest)?;
             }
@@ -254,8 +272,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
                 let a = this.read_scalar(a)?.to_f32()?;
                 let b = this.read_scalar(b)?.to_f32()?;
                 let c = this.read_scalar(c)?.to_f32()?;
-                // FIXME: Using host floats, to work around https://github.com/rust-lang/rustc_apfloat/issues/11
-                let res = a.to_host().mul_add(b.to_host(), c.to_host()).to_soft();
+                let res = a.mul_add(b, c).value;
                 let res = this.adjust_nan(res, &[a, b, c]);
                 this.write_scalar(res, dest)?;
             }
@@ -264,8 +281,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
                 let a = this.read_scalar(a)?.to_f64()?;
                 let b = this.read_scalar(b)?.to_f64()?;
                 let c = this.read_scalar(c)?.to_f64()?;
-                // FIXME: Using host floats, to work around https://github.com/rust-lang/rustc_apfloat/issues/11
-                let res = a.to_host().mul_add(b.to_host(), c.to_host()).to_soft();
+                let res = a.mul_add(b, c).value;
                 let res = this.adjust_nan(res, &[a, b, c]);
                 this.write_scalar(res, dest)?;
             }
@@ -275,13 +291,8 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
                 let a = this.read_scalar(a)?.to_f32()?;
                 let b = this.read_scalar(b)?.to_f32()?;
                 let c = this.read_scalar(c)?.to_f32()?;
-                let fuse: bool = this.machine.rng.get_mut().random();
-                let res = if fuse {
-                    // FIXME: Using host floats, to work around https://github.com/rust-lang/rustc_apfloat/issues/11
-                    a.to_host().mul_add(b.to_host(), c.to_host()).to_soft()
-                } else {
-                    ((a * b).value + c).value
-                };
+                let fuse: bool = this.machine.float_nondet && this.machine.rng.get_mut().random();
+                let res = if fuse { a.mul_add(b, c).value } else { ((a * b).value + c).value };
                 let res = this.adjust_nan(res, &[a, b, c]);
                 this.write_scalar(res, dest)?;
             }
@@ -290,55 +301,82 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
                 let a = this.read_scalar(a)?.to_f64()?;
                 let b = this.read_scalar(b)?.to_f64()?;
                 let c = this.read_scalar(c)?.to_f64()?;
-                let fuse: bool = this.machine.rng.get_mut().random();
-                let res = if fuse {
-                    // FIXME: Using host floats, to work around https://github.com/rust-lang/rustc_apfloat/issues/11
-                    a.to_host().mul_add(b.to_host(), c.to_host()).to_soft()
-                } else {
-                    ((a * b).value + c).value
-                };
+                let fuse: bool = this.machine.float_nondet && this.machine.rng.get_mut().random();
+                let res = if fuse { a.mul_add(b, c).value } else { ((a * b).value + c).value };
                 let res = this.adjust_nan(res, &[a, b, c]);
                 this.write_scalar(res, dest)?;
             }
 
             "powf32" => {
-                // FIXME: apply random relative error but without altering behaviour of powf
                 let [f1, f2] = check_intrinsic_arg_count(args)?;
                 let f1 = this.read_scalar(f1)?.to_f32()?;
                 let f2 = this.read_scalar(f2)?.to_f32()?;
-                // Using host floats (but it's fine, this operation does not have guaranteed precision).
-                let res = f1.to_host().powf(f2.to_host()).to_soft();
+
+                let res = fixed_float_value(intrinsic_name, &[f1, f2]).unwrap_or_else(|| {
+                    // Using host floats (but it's fine, this operation does not have guaranteed precision).
+                    let res = f1.to_host().powf(f2.to_host()).to_soft();
+
+                    // Apply a relative error of 4ULP to introduce some non-determinism
+                    // simulating imprecise implementations and optimizations.
+                    apply_random_float_error_ulp(
+                        this, res, 2, // log2(4)
+                    )
+                });
                 let res = this.adjust_nan(res, &[f1, f2]);
                 this.write_scalar(res, dest)?;
             }
             "powf64" => {
-                // FIXME: apply random relative error but without altering behaviour of powf
                 let [f1, f2] = check_intrinsic_arg_count(args)?;
                 let f1 = this.read_scalar(f1)?.to_f64()?;
                 let f2 = this.read_scalar(f2)?.to_f64()?;
-                // Using host floats (but it's fine, this operation does not have guaranteed precision).
-                let res = f1.to_host().powf(f2.to_host()).to_soft();
+
+                let res = fixed_float_value(intrinsic_name, &[f1, f2]).unwrap_or_else(|| {
+                    // Using host floats (but it's fine, this operation does not have guaranteed precision).
+                    let res = f1.to_host().powf(f2.to_host()).to_soft();
+
+                    // Apply a relative error of 4ULP to introduce some non-determinism
+                    // simulating imprecise implementations and optimizations.
+                    apply_random_float_error_ulp(
+                        this, res, 2, // log2(4)
+                    )
+                });
                 let res = this.adjust_nan(res, &[f1, f2]);
                 this.write_scalar(res, dest)?;
             }
 
             "powif32" => {
-                // FIXME: apply random relative error but without altering behaviour of powi
                 let [f, i] = check_intrinsic_arg_count(args)?;
                 let f = this.read_scalar(f)?.to_f32()?;
                 let i = this.read_scalar(i)?.to_i32()?;
-                // Using host floats (but it's fine, this operation does not have guaranteed precision).
-                let res = f.to_host().powi(i).to_soft();
+
+                let res = fixed_powi_float_value(f, i).unwrap_or_else(|| {
+                    // Using host floats (but it's fine, this operation does not have guaranteed precision).
+                    let res = f.to_host().powi(i).to_soft();
+
+                    // Apply a relative error of 4ULP to introduce some non-determinism
+                    // simulating imprecise implementations and optimizations.
+                    apply_random_float_error_ulp(
+                        this, res, 2, // log2(4)
+                    )
+                });
                 let res = this.adjust_nan(res, &[f]);
                 this.write_scalar(res, dest)?;
             }
             "powif64" => {
-                // FIXME: apply random relative error but without altering behaviour of powi
                 let [f, i] = check_intrinsic_arg_count(args)?;
                 let f = this.read_scalar(f)?.to_f64()?;
                 let i = this.read_scalar(i)?.to_i32()?;
-                // Using host floats (but it's fine, this operation does not have guaranteed precision).
-                let res = f.to_host().powi(i).to_soft();
+
+                let res = fixed_powi_float_value(f, i).unwrap_or_else(|| {
+                    // Using host floats (but it's fine, this operation does not have guaranteed precision).
+                    let res = f.to_host().powi(i).to_soft();
+
+                    // Apply a relative error of 4ULP to introduce some non-determinism
+                    // simulating imprecise implementations and optimizations.
+                    apply_random_float_error_ulp(
+                        this, res, 2, // log2(4)
+                    )
+                });
                 let res = this.adjust_nan(res, &[f]);
                 this.write_scalar(res, dest)?;
             }
@@ -425,3 +463,97 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
         interp_ok(EmulateItemResult::NeedsReturn)
     }
 }
+
+/// Applies a random ULP floating point error to `val` and returns the new value.
+/// So if you want an X ULP error, `ulp_exponent` should be log2(X).
+///
+/// Will fail if `val` is not a floating point number.
+fn apply_random_float_error_to_imm<'tcx>(
+    ecx: &mut MiriInterpCx<'tcx>,
+    val: ImmTy<'tcx>,
+    ulp_exponent: u32,
+) -> InterpResult<'tcx, ImmTy<'tcx>> {
+    let scalar = val.to_scalar_int()?;
+    let res: ScalarInt = match val.layout.ty.kind() {
+        ty::Float(FloatTy::F16) =>
+            apply_random_float_error_ulp(ecx, scalar.to_f16(), ulp_exponent).into(),
+        ty::Float(FloatTy::F32) =>
+            apply_random_float_error_ulp(ecx, scalar.to_f32(), ulp_exponent).into(),
+        ty::Float(FloatTy::F64) =>
+            apply_random_float_error_ulp(ecx, scalar.to_f64(), ulp_exponent).into(),
+        ty::Float(FloatTy::F128) =>
+            apply_random_float_error_ulp(ecx, scalar.to_f128(), ulp_exponent).into(),
+        _ => bug!("intrinsic called with non-float input type"),
+    };
+
+    interp_ok(ImmTy::from_scalar_int(res, val.layout))
+}
+
+/// For the intrinsics:
+/// - sinf32, sinf64
+/// - cosf32, cosf64
+/// - expf32, expf64, exp2f32, exp2f64
+/// - logf32, logf64, log2f32, log2f64, log10f32, log10f64
+/// - powf32, powf64
+///
+/// Returns `Some(output)` if the `intrinsic` results in a defined fixed `output` specified in the C standard
+/// (specifically, C23 annex F.10)  when given `args` as arguments. Outputs that are unaffected by a relative error
+/// (such as INF and zero) are not handled here, they are assumed to be handled by the underlying
+/// implementation. Returns `None` if no specific value is guaranteed.
+fn fixed_float_value<S: Semantics>(
+    intrinsic_name: &str,
+    args: &[IeeeFloat<S>],
+) -> Option<IeeeFloat<S>> {
+    let one = IeeeFloat::<S>::one();
+    match (intrinsic_name, args) {
+        // cos(+- 0) = 1
+        ("cosf32" | "cosf64", [input]) if input.is_zero() => Some(one),
+
+        // e^0 = 1
+        ("expf32" | "expf64" | "exp2f32" | "exp2f64", [input]) if input.is_zero() => Some(one),
+
+        // 1^y = 1 for any y, even a NaN.
+        ("powf32" | "powf64", [base, _]) if *base == one => Some(one),
+
+        // (-1)^(±INF) = 1
+        ("powf32" | "powf64", [base, exp]) if *base == -one && exp.is_infinite() => Some(one),
+
+        // FIXME(#4286): The C ecosystem is inconsistent with handling sNaN's, some return 1 others propogate
+        // the NaN. We should return either 1 or the NaN non-deterministically here.
+        // But for now, just handle them all the same.
+        // x^(±0) = 1 for any x, even a NaN
+        ("powf32" | "powf64", [_, exp]) if exp.is_zero() => Some(one),
+
+        // There are a lot of cases for fixed outputs according to the C Standard, but these are mainly INF or zero
+        // which are not affected by the applied error.
+        _ => None,
+    }
+}
+
+/// Returns `Some(output)` if `powi` (called `pown` in C) results in a fixed value specified in the C standard
+/// (specifically, C23 annex F.10.4.6) when doing `base^exp`. Otherwise, returns `None`.
+fn fixed_powi_float_value<S: Semantics>(base: IeeeFloat<S>, exp: i32) -> Option<IeeeFloat<S>> {
+    match (base.category(), exp) {
+        // x^0 = 1, if x is not a Signaling NaN
+        // FIXME(#4286): The C ecosystem is inconsistent with handling sNaN's, some return 1 others propogate
+        // the NaN. We should return either 1 or the NaN non-deterministically here.
+        // But for now, just handle them all the same.
+        (_, 0) => Some(IeeeFloat::<S>::one()),
+
+        _ => None,
+    }
+}
+
+/// Given an floating-point operation and a floating-point value, clamps the result to the output
+/// range of the given operation.
+fn clamp_float_value<S: Semantics>(intrinsic_name: &str, val: IeeeFloat<S>) -> IeeeFloat<S> {
+    match intrinsic_name {
+        // sin and cos: [-1, 1]
+        "sinf32" | "cosf32" | "sinf64" | "cosf64" =>
+            val.clamp(IeeeFloat::<S>::one().neg(), IeeeFloat::<S>::one()),
+        // exp: [0, +INF]
+        "expf32" | "exp2f32" | "expf64" | "exp2f64" =>
+            IeeeFloat::<S>::maximum(val, IeeeFloat::<S>::ZERO),
+        _ => val,
+    }
+}
diff --git a/src/tools/miri/src/intrinsics/simd.rs b/src/tools/miri/src/intrinsics/simd.rs
index b17fd4fb7f9..dbe193bdbda 100644
--- a/src/tools/miri/src/intrinsics/simd.rs
+++ b/src/tools/miri/src/intrinsics/simd.rs
@@ -306,7 +306,8 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
                     let c = this.read_scalar(&this.project_index(&c, i)?)?;
                     let dest = this.project_index(&dest, i)?;
 
-                    let fuse: bool = intrinsic_name == "fma" || this.machine.rng.get_mut().random();
+                    let fuse: bool = intrinsic_name == "fma"
+                        || (this.machine.float_nondet && this.machine.rng.get_mut().random());
 
                     // Works for f32 and f64.
                     // FIXME: using host floats to work around https://github.com/rust-lang/miri/issues/2468.
@@ -320,7 +321,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
                             let b = b.to_f32()?;
                             let c = c.to_f32()?;
                             let res = if fuse {
-                                a.to_host().mul_add(b.to_host(), c.to_host()).to_soft()
+                                a.mul_add(b, c).value
                             } else {
                                 ((a * b).value + c).value
                             };
@@ -332,7 +333,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
                             let b = b.to_f64()?;
                             let c = c.to_f64()?;
                             let res = if fuse {
-                                a.to_host().mul_add(b.to_host(), c.to_host()).to_soft()
+                                a.mul_add(b, c).value
                             } else {
                                 ((a * b).value + c).value
                             };
diff --git a/src/tools/miri/src/lib.rs b/src/tools/miri/src/lib.rs
index 51ec19af52a..e96c81d5b1d 100644
--- a/src/tools/miri/src/lib.rs
+++ b/src/tools/miri/src/lib.rs
@@ -16,6 +16,7 @@
 #![feature(unqualified_local_imports)]
 #![feature(derive_coerce_pointee)]
 #![feature(arbitrary_self_types)]
+#![cfg_attr(bootstrap, feature(file_lock))]
 // Configure clippy and other lints
 #![allow(
     clippy::collapsible_else_if,
@@ -113,7 +114,9 @@ pub use crate::borrow_tracker::stacked_borrows::{
     EvalContextExt as _, Item, Permission, Stack, Stacks,
 };
 pub use crate::borrow_tracker::tree_borrows::{EvalContextExt as _, Tree};
-pub use crate::borrow_tracker::{BorTag, BorrowTrackerMethod, EvalContextExt as _, RetagFields};
+pub use crate::borrow_tracker::{
+    BorTag, BorrowTrackerMethod, EvalContextExt as _, RetagFields, TreeBorrowsParams,
+};
 pub use crate::clock::{Instant, MonotonicClock};
 pub use crate::concurrency::cpu_affinity::MAX_CPUS;
 pub use crate::concurrency::data_race::{
@@ -121,7 +124,7 @@ pub use crate::concurrency::data_race::{
 };
 pub use crate::concurrency::init_once::{EvalContextExt as _, InitOnceId};
 pub use crate::concurrency::sync::{
-    CondvarId, EvalContextExt as _, MutexRef, RwLockId, SynchronizationObjects,
+    CondvarId, EvalContextExt as _, MutexRef, RwLockRef, SynchronizationObjects,
 };
 pub use crate::concurrency::thread::{
     BlockReason, DynUnblockCallback, EvalContextExt as _, StackEmptyCallback, ThreadId,
diff --git a/src/tools/miri/src/machine.rs b/src/tools/miri/src/machine.rs
index 15b3653d7ae..b4d7db34efa 100644
--- a/src/tools/miri/src/machine.rs
+++ b/src/tools/miri/src/machine.rs
@@ -558,9 +558,9 @@ pub struct MiriMachine<'tcx> {
 
     /// Handle of the optional shared object file for native functions.
     #[cfg(unix)]
-    pub native_lib: Option<(libloading::Library, std::path::PathBuf)>,
+    pub native_lib: Vec<(libloading::Library, std::path::PathBuf)>,
     #[cfg(not(unix))]
-    pub native_lib: Option<!>,
+    pub native_lib: Vec<!>,
 
     /// Run a garbage collector for BorTags every N basic blocks.
     pub(crate) gc_interval: u32,
@@ -618,6 +618,9 @@ pub struct MiriMachine<'tcx> {
 
     /// Always prefer the intrinsic fallback body over the native Miri implementation.
     pub force_intrinsic_fallback: bool,
+
+    /// Whether floating-point operations can behave non-deterministically.
+    pub float_nondet: bool,
 }
 
 impl<'tcx> MiriMachine<'tcx> {
@@ -720,7 +723,7 @@ impl<'tcx> MiriMachine<'tcx> {
             extern_statics: FxHashMap::default(),
             rng: RefCell::new(rng),
             #[cfg(target_os = "linux")]
-            allocator: if config.native_lib.is_some() {
+            allocator: if !config.native_lib.is_empty() {
                 Some(Rc::new(RefCell::new(crate::alloc::isolated_alloc::IsolatedAlloc::new())))
             } else { None },
             tracked_alloc_ids: config.tracked_alloc_ids.clone(),
@@ -732,7 +735,7 @@ impl<'tcx> MiriMachine<'tcx> {
             basic_block_count: 0,
             monotonic_clock: MonotonicClock::new(config.isolated_op == IsolatedOp::Allow),
             #[cfg(unix)]
-            native_lib: config.native_lib.as_ref().map(|lib_file_path| {
+            native_lib: config.native_lib.iter().map(|lib_file_path| {
                 let host_triple = rustc_session::config::host_tuple();
                 let target_triple = tcx.sess.opts.target_triple.tuple();
                 // Check if host target == the session target.
@@ -752,11 +755,11 @@ impl<'tcx> MiriMachine<'tcx> {
                     },
                     lib_file_path.clone(),
                 )
-            }),
+            }).collect(),
             #[cfg(not(unix))]
-            native_lib: config.native_lib.as_ref().map(|_| {
+            native_lib: config.native_lib.iter().map(|_| {
                 panic!("calling functions from native libraries via FFI is only supported on Unix")
-            }),
+            }).collect(),
             gc_interval: config.gc_interval,
             since_gc: 0,
             num_cpus: config.num_cpus,
@@ -778,6 +781,7 @@ impl<'tcx> MiriMachine<'tcx> {
             int2ptr_warned: Default::default(),
             mangle_internal_symbol_cache: Default::default(),
             force_intrinsic_fallback: config.force_intrinsic_fallback,
+            float_nondet: config.float_nondet,
         }
     }
 
@@ -956,6 +960,7 @@ impl VisitProvenance for MiriMachine<'_> {
             int2ptr_warned: _,
             mangle_internal_symbol_cache: _,
             force_intrinsic_fallback: _,
+            float_nondet: _,
         } = self;
 
         threads.visit_provenance(visit);
diff --git a/src/tools/miri/src/math.rs b/src/tools/miri/src/math.rs
index 2ff29c7ac1a..cf16a5676d6 100644
--- a/src/tools/miri/src/math.rs
+++ b/src/tools/miri/src/math.rs
@@ -15,6 +15,10 @@ pub(crate) fn apply_random_float_error<F: rustc_apfloat::Float>(
     val: F,
     err_scale: i32,
 ) -> F {
+    if !ecx.machine.float_nondet {
+        return val;
+    }
+
     let rng = ecx.machine.rng.get_mut();
     // Generate a random integer in the range [0, 2^PREC).
     // (When read as binary, the position of the first `1` determines the exponent,
@@ -151,6 +155,20 @@ pub(crate) fn sqrt<S: rustc_apfloat::ieee::Semantics>(x: IeeeFloat<S>) -> IeeeFl
     }
 }
 
+/// Extend functionality of rustc_apfloat softfloats
+pub trait IeeeExt: rustc_apfloat::Float {
+    #[inline]
+    fn one() -> Self {
+        Self::from_u128(1).value
+    }
+
+    #[inline]
+    fn clamp(self, min: Self, max: Self) -> Self {
+        self.maximum(min).minimum(max)
+    }
+}
+impl<S: rustc_apfloat::ieee::Semantics> IeeeExt for IeeeFloat<S> {}
+
 #[cfg(test)]
 mod tests {
     use rustc_apfloat::ieee::{DoubleS, HalfS, IeeeFloat, QuadS, SingleS};
diff --git a/src/tools/miri/src/operator.rs b/src/tools/miri/src/operator.rs
index 81f22b2d0b2..73d671121f6 100644
--- a/src/tools/miri/src/operator.rs
+++ b/src/tools/miri/src/operator.rs
@@ -76,6 +76,11 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
     }
 
     fn generate_nan<F1: Float + FloatConvert<F2>, F2: Float>(&self, inputs: &[F1]) -> F2 {
+        let this = self.eval_context_ref();
+        if !this.machine.float_nondet {
+            return F2::NAN;
+        }
+
         /// Make the given NaN a signaling NaN.
         /// Returns `None` if this would not result in a NaN.
         fn make_signaling<F: Float>(f: F) -> Option<F> {
@@ -89,7 +94,6 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
             if f.is_nan() { Some(f) } else { None }
         }
 
-        let this = self.eval_context_ref();
         let mut rand = this.machine.rng.borrow_mut();
         // Assemble an iterator of possible NaNs: preferred, quieting propagation, unchanged propagation.
         // On some targets there are more possibilities; for now we just generate those options that
@@ -118,6 +122,9 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
 
     fn equal_float_min_max<F: Float>(&self, a: F, b: F) -> F {
         let this = self.eval_context_ref();
+        if !this.machine.float_nondet {
+            return a;
+        }
         // Return one side non-deterministically.
         let mut rand = this.machine.rng.borrow_mut();
         if rand.random() { a } else { b }
diff --git a/src/tools/miri/src/shims/alloc.rs b/src/tools/miri/src/shims/alloc.rs
index d7bb16f0858..f05c5fbbe1d 100644
--- a/src/tools/miri/src/shims/alloc.rs
+++ b/src/tools/miri/src/shims/alloc.rs
@@ -15,11 +15,14 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
         // This is given by `alignof(max_align_t)`. The following list is taken from
         // `library/std/src/sys/alloc/mod.rs` (where this is called `MIN_ALIGN`) and should
         // be kept in sync.
+        let os = this.tcx.sess.target.os.as_ref();
         let max_fundamental_align = match this.tcx.sess.target.arch.as_ref() {
-            "x86" | "arm" | "loongarch32" | "mips" | "mips32r6" | "powerpc" | "powerpc64"
-            | "wasm32" => 8,
-            "x86_64" | "aarch64" | "mips64" | "mips64r6" | "s390x" | "sparc64" | "loongarch64" =>
-                16,
+            "riscv32" if matches!(os, "espidf" | "zkvm") => 4,
+            "xtensa" if matches!(os, "espidf") => 4,
+            "x86" | "arm" | "m68k" | "csky" | "loongarch32" | "mips" | "mips32r6" | "powerpc"
+            | "powerpc64" | "sparc" | "wasm32" | "hexagon" | "riscv32" | "xtensa" => 8,
+            "x86_64" | "aarch64" | "arm64ec" | "loongarch64" | "mips64" | "mips64r6" | "s390x"
+            | "sparc64" | "riscv64" | "wasm64" => 16,
             arch => bug!("unsupported target architecture for malloc: `{}`", arch),
         };
         // The C standard only requires sufficient alignment for any *type* with size less than or
diff --git a/src/tools/miri/src/shims/backtrace.rs b/src/tools/miri/src/shims/backtrace.rs
index 8606735c913..feb83ca8829 100644
--- a/src/tools/miri/src/shims/backtrace.rs
+++ b/src/tools/miri/src/shims/backtrace.rs
@@ -169,8 +169,14 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
             _ => throw_unsup_format!("unknown `miri_resolve_frame` flags {}", flags),
         }
 
-        this.write_scalar(Scalar::from_u32(lineno), &this.project_field(dest, FieldIdx::from_u32(2))?)?;
-        this.write_scalar(Scalar::from_u32(colno), &this.project_field(dest, FieldIdx::from_u32(3))?)?;
+        this.write_scalar(
+            Scalar::from_u32(lineno),
+            &this.project_field(dest, FieldIdx::from_u32(2))?,
+        )?;
+        this.write_scalar(
+            Scalar::from_u32(colno),
+            &this.project_field(dest, FieldIdx::from_u32(3))?,
+        )?;
 
         // Support a 4-field struct for now - this is deprecated
         // and slated for removal.
diff --git a/src/tools/miri/src/shims/foreign_items.rs b/src/tools/miri/src/shims/foreign_items.rs
index ae04ca018ab..39b930fdeb9 100644
--- a/src/tools/miri/src/shims/foreign_items.rs
+++ b/src/tools/miri/src/shims/foreign_items.rs
@@ -238,7 +238,7 @@ trait EvalContextExtPriv<'tcx>: crate::MiriInterpCxExt<'tcx> {
 
         // First deal with any external C functions in linked .so file.
         #[cfg(unix)]
-        if this.machine.native_lib.as_ref().is_some() {
+        if !this.machine.native_lib.is_empty() {
             use crate::shims::native_lib::EvalContextExt as _;
             // An Ok(false) here means that the function being called was not exported
             // by the specified `.so` file; we should continue and check if it corresponds to
diff --git a/src/tools/miri/src/shims/native_lib.rs b/src/tools/miri/src/shims/native_lib.rs
index 1e6c93333c1..030c2e36721 100644
--- a/src/tools/miri/src/shims/native_lib.rs
+++ b/src/tools/miri/src/shims/native_lib.rs
@@ -72,7 +72,7 @@ trait EvalContextExtPriv<'tcx>: crate::MiriInterpCxExt<'tcx> {
             }
             // Functions with no declared return type (i.e., the default return)
             // have the output_type `Tuple([])`.
-            ty::Tuple(t_list) if t_list.is_empty() => {
+            ty::Tuple(t_list) if (*t_list).deref().is_empty() => {
                 unsafe { ffi::call::<()>(ptr, libffi_args.as_slice()) };
                 return interp_ok(ImmTy::uninit(dest.layout));
             }
@@ -87,31 +87,35 @@ trait EvalContextExtPriv<'tcx>: crate::MiriInterpCxExt<'tcx> {
     }
 
     /// Get the pointer to the function of the specified name in the shared object file,
-    /// if it exists. The function must be in the shared object file specified: we do *not*
-    /// return pointers to functions in dependencies of the library.  
+    /// if it exists. The function must be in one of the shared object files specified:
+    /// we do *not* return pointers to functions in dependencies of libraries.
     fn get_func_ptr_explicitly_from_lib(&mut self, link_name: Symbol) -> Option<CodePtr> {
         let this = self.eval_context_mut();
-        // Try getting the function from the shared library.
-        let (lib, lib_path) = this.machine.native_lib.as_ref().unwrap();
-        let func: libloading::Symbol<'_, unsafe extern "C" fn()> =
-            unsafe { lib.get(link_name.as_str().as_bytes()).ok()? };
-        #[expect(clippy::as_conversions)] // fn-ptr to raw-ptr cast needs `as`.
-        let fn_ptr = *func.deref() as *mut std::ffi::c_void;
+        // Try getting the function from one of the shared libraries.
+        for (lib, lib_path) in &this.machine.native_lib {
+            let Ok(func): Result<libloading::Symbol<'_, unsafe extern "C" fn()>, _> =
+                (unsafe { lib.get(link_name.as_str().as_bytes()) })
+            else {
+                continue;
+            };
+            #[expect(clippy::as_conversions)] // fn-ptr to raw-ptr cast needs `as`.
+            let fn_ptr = *func.deref() as *mut std::ffi::c_void;
 
-        // FIXME: this is a hack!
-        // The `libloading` crate will automatically load system libraries like `libc`.
-        // On linux `libloading` is based on `dlsym`: https://docs.rs/libloading/0.7.3/src/libloading/os/unix/mod.rs.html#202
-        // and `dlsym`(https://linux.die.net/man/3/dlsym) looks through the dependency tree of the
-        // library if it can't find the symbol in the library itself.
-        // So, in order to check if the function was actually found in the specified
-        // `machine.external_so_lib` we need to check its `dli_fname` and compare it to
-        // the specified SO file path.
-        // This code is a reimplementation of the mechanism for getting `dli_fname` in `libloading`,
-        // from: https://docs.rs/libloading/0.7.3/src/libloading/os/unix/mod.rs.html#411
-        // using the `libc` crate where this interface is public.
-        let mut info = std::mem::MaybeUninit::<libc::Dl_info>::zeroed();
-        unsafe {
-            if libc::dladdr(fn_ptr, info.as_mut_ptr()) != 0 {
+            // FIXME: this is a hack!
+            // The `libloading` crate will automatically load system libraries like `libc`.
+            // On linux `libloading` is based on `dlsym`: https://docs.rs/libloading/0.7.3/src/libloading/os/unix/mod.rs.html#202
+            // and `dlsym`(https://linux.die.net/man/3/dlsym) looks through the dependency tree of the
+            // library if it can't find the symbol in the library itself.
+            // So, in order to check if the function was actually found in the specified
+            // `machine.external_so_lib` we need to check its `dli_fname` and compare it to
+            // the specified SO file path.
+            // This code is a reimplementation of the mechanism for getting `dli_fname` in `libloading`,
+            // from: https://docs.rs/libloading/0.7.3/src/libloading/os/unix/mod.rs.html#411
+            // using the `libc` crate where this interface is public.
+            let mut info = std::mem::MaybeUninit::<libc::Dl_info>::zeroed();
+            unsafe {
+                let res = libc::dladdr(fn_ptr, info.as_mut_ptr());
+                assert!(res != 0, "failed to load info about function we already loaded");
                 let info = info.assume_init();
                 #[cfg(target_os = "cygwin")]
                 let fname_ptr = info.dli_fname.as_ptr();
@@ -121,13 +125,15 @@ trait EvalContextExtPriv<'tcx>: crate::MiriInterpCxExt<'tcx> {
                 if std::ffi::CStr::from_ptr(fname_ptr).to_str().unwrap()
                     != lib_path.to_str().unwrap()
                 {
-                    return None;
+                    // The function is not actually in this .so, check the next one.
+                    continue;
                 }
             }
-        }
 
-        // Return a pointer to the function.
-        Some(CodePtr(fn_ptr))
+            // Return a pointer to the function.
+            return Some(CodePtr(fn_ptr));
+        }
+        None
     }
 }
 
diff --git a/src/tools/miri/src/shims/unix/fs.rs b/src/tools/miri/src/shims/unix/fs.rs
index 31cb269059c..0f7d453b296 100644
--- a/src/tools/miri/src/shims/unix/fs.rs
+++ b/src/tools/miri/src/shims/unix/fs.rs
@@ -2,7 +2,8 @@
 
 use std::borrow::Cow;
 use std::fs::{
-    DirBuilder, File, FileType, OpenOptions, ReadDir, read_dir, remove_dir, remove_file, rename,
+    DirBuilder, File, FileType, OpenOptions, ReadDir, TryLockError, read_dir, remove_dir,
+    remove_file, rename,
 };
 use std::io::{self, ErrorKind, Read, Seek, SeekFrom, Write};
 use std::path::{Path, PathBuf};
@@ -89,103 +90,27 @@ impl UnixFileDescription for FileHandle {
         communicate_allowed: bool,
         op: FlockOp,
     ) -> InterpResult<'tcx, io::Result<()>> {
-        // cfg(bootstrap)
-        macro_rules! cfg_select_dispatch {
-            ($($tokens:tt)*) => {
-                #[cfg(bootstrap)]
-                cfg_match! { $($tokens)* }
-
-                #[cfg(not(bootstrap))]
-                cfg_select! { $($tokens)* }
-            };
-        }
-
         assert!(communicate_allowed, "isolation should have prevented even opening a file");
-        cfg_select_dispatch! {
-            all(target_family = "unix", not(target_os = "solaris")) => {
-                use std::os::fd::AsRawFd;
-
-                use FlockOp::*;
-                // We always use non-blocking call to prevent interpreter from being blocked
-                let (host_op, lock_nb) = match op {
-                    SharedLock { nonblocking } => (libc::LOCK_SH | libc::LOCK_NB, nonblocking),
-                    ExclusiveLock { nonblocking } => (libc::LOCK_EX | libc::LOCK_NB, nonblocking),
-                    Unlock => (libc::LOCK_UN, false),
-                };
 
-                let fd = self.file.as_raw_fd();
-                let ret = unsafe { libc::flock(fd, host_op) };
-                let res = match ret {
-                    0 => Ok(()),
-                    -1 => {
-                        let err = io::Error::last_os_error();
-                        if !lock_nb && err.kind() == io::ErrorKind::WouldBlock {
-                            throw_unsup_format!("blocking `flock` is not currently supported");
-                        }
-                        Err(err)
-                    }
-                    ret => panic!("Unexpected return value from flock: {ret}"),
-                };
-                interp_ok(res)
+        use FlockOp::*;
+        // We must not block the interpreter loop, so we always `try_lock`.
+        let (res, nonblocking) = match op {
+            SharedLock { nonblocking } => (self.file.try_lock_shared(), nonblocking),
+            ExclusiveLock { nonblocking } => (self.file.try_lock(), nonblocking),
+            Unlock => {
+                return interp_ok(self.file.unlock());
             }
-            target_family = "windows" => {
-                use std::os::windows::io::AsRawHandle;
-
-                use windows_sys::Win32::Foundation::{
-                    ERROR_IO_PENDING, ERROR_LOCK_VIOLATION, FALSE, TRUE,
-                };
-                use windows_sys::Win32::Storage::FileSystem::{
-                    LOCKFILE_EXCLUSIVE_LOCK, LOCKFILE_FAIL_IMMEDIATELY, LockFileEx, UnlockFile,
-                };
-
-                let fh = self.file.as_raw_handle();
-
-                use FlockOp::*;
-                let (ret, lock_nb) = match op {
-                    SharedLock { nonblocking } | ExclusiveLock { nonblocking } => {
-                        // We always use non-blocking call to prevent interpreter from being blocked
-                        let mut flags = LOCKFILE_FAIL_IMMEDIATELY;
-                        if matches!(op, ExclusiveLock { .. }) {
-                            flags |= LOCKFILE_EXCLUSIVE_LOCK;
-                        }
-                        let ret = unsafe { LockFileEx(fh, flags, 0, !0, !0, &mut std::mem::zeroed()) };
-                        (ret, nonblocking)
-                    }
-                    Unlock => {
-                        let ret = unsafe { UnlockFile(fh, 0, 0, !0, !0) };
-                        (ret, false)
-                    }
-                };
+        };
 
-                let res = match ret {
-                    TRUE => Ok(()),
-                    FALSE => {
-                        let mut err = io::Error::last_os_error();
-                        // This only runs on Windows hosts so we can use `raw_os_error`.
-                        // We have to be careful not to forward that error code to target code.
-                        let code: u32 = err.raw_os_error().unwrap().try_into().unwrap();
-                        if matches!(code, ERROR_IO_PENDING | ERROR_LOCK_VIOLATION) {
-                            if lock_nb {
-                                // The io error mapping does not know about these error codes,
-                                // so we translate it to `WouldBlock` manually.
-                                let desc = format!("LockFileEx wouldblock error: {err}");
-                                err = io::Error::new(io::ErrorKind::WouldBlock, desc);
-                            } else {
-                                throw_unsup_format!("blocking `flock` is not currently supported");
-                            }
-                        }
-                        Err(err)
-                    }
-                    _ => panic!("Unexpected return value: {ret}"),
-                };
-                interp_ok(res)
-            }
-            _ => {
-                let _ = op;
-                throw_unsup_format!(
-                    "flock is supported only on UNIX (except Solaris) and Windows hosts"
-                );
-            }
+        match res {
+            Ok(()) => interp_ok(Ok(())),
+            Err(TryLockError::Error(err)) => interp_ok(Err(err)),
+            Err(TryLockError::WouldBlock) =>
+                if nonblocking {
+                    interp_ok(Err(ErrorKind::WouldBlock.into()))
+                } else {
+                    throw_unsup_format!("blocking `flock` is not currently supported");
+                },
         }
     }
 }
diff --git a/src/tools/miri/src/shims/unix/linux_like/epoll.rs b/src/tools/miri/src/shims/unix/linux_like/epoll.rs
index f971fb10b19..d460abc783d 100644
--- a/src/tools/miri/src/shims/unix/linux_like/epoll.rs
+++ b/src/tools/miri/src/shims/unix/linux_like/epoll.rs
@@ -286,7 +286,8 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
 
         if op == epoll_ctl_add || op == epoll_ctl_mod {
             // Read event bitmask and data from epoll_event passed by caller.
-            let mut events = this.read_scalar(&this.project_field(&event, FieldIdx::ZERO)?)?.to_u32()?;
+            let mut events =
+                this.read_scalar(&this.project_field(&event, FieldIdx::ZERO)?)?.to_u32()?;
             let data = this.read_scalar(&this.project_field(&event, FieldIdx::ONE)?)?.to_u64()?;
 
             // Unset the flag we support to discover if any unsupported flags are used.
diff --git a/src/tools/miri/src/shims/unix/macos/sync.rs b/src/tools/miri/src/shims/unix/macos/sync.rs
index 6ba52f2f57e..19f55e6c917 100644
--- a/src/tools/miri/src/shims/unix/macos/sync.rs
+++ b/src/tools/miri/src/shims/unix/macos/sync.rs
@@ -289,15 +289,15 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
         };
         let mutex_ref = mutex_ref.clone();
 
-        if this.mutex_is_locked(&mutex_ref) {
-            if this.mutex_get_owner(&mutex_ref) == this.active_thread() {
+        if let Some(owner) = mutex_ref.owner() {
+            if owner == this.active_thread() {
                 // Matching the current macOS implementation: abort on reentrant locking.
                 throw_machine_stop!(TerminationInfo::Abort(
                     "attempted to lock an os_unfair_lock that is already locked by the current thread".to_owned()
                 ));
             }
 
-            this.mutex_enqueue_and_block(&mutex_ref, None);
+            this.mutex_enqueue_and_block(mutex_ref, None);
         } else {
             this.mutex_lock(&mutex_ref);
         }
@@ -319,7 +319,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
         };
         let mutex_ref = mutex_ref.clone();
 
-        if this.mutex_is_locked(&mutex_ref) {
+        if mutex_ref.owner().is_some() {
             // Contrary to the blocking lock function, this does not check for
             // reentrancy.
             this.write_scalar(Scalar::from_bool(false), dest)?;
@@ -350,9 +350,9 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
             ));
         }
 
-        // If the lock is not locked by anyone now, it went quer.
+        // If the lock is not locked by anyone now, it went quiet.
         // Reset to zero so that it can be moved and initialized again for the next phase.
-        if !this.mutex_is_locked(&mutex_ref) {
+        if mutex_ref.owner().is_none() {
             let lock_place = this.deref_pointer_as(lock_op, this.machine.layouts.u32)?;
             this.write_scalar_atomic(Scalar::from_u32(0), &lock_place, AtomicWriteOrd::Relaxed)?;
         }
@@ -371,9 +371,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
         };
         let mutex_ref = mutex_ref.clone();
 
-        if !this.mutex_is_locked(&mutex_ref)
-            || this.mutex_get_owner(&mutex_ref) != this.active_thread()
-        {
+        if mutex_ref.owner().is_none_or(|o| o != this.active_thread()) {
             throw_machine_stop!(TerminationInfo::Abort(
                 "called os_unfair_lock_assert_owner on an os_unfair_lock not owned by the current thread".to_owned()
             ));
@@ -393,17 +391,15 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
         };
         let mutex_ref = mutex_ref.clone();
 
-        if this.mutex_is_locked(&mutex_ref)
-            && this.mutex_get_owner(&mutex_ref) == this.active_thread()
-        {
+        if mutex_ref.owner().is_some_and(|o| o == this.active_thread()) {
             throw_machine_stop!(TerminationInfo::Abort(
                 "called os_unfair_lock_assert_not_owner on an os_unfair_lock owned by the current thread".to_owned()
             ));
         }
 
-        // If the lock is not locked by anyone now, it went quer.
+        // If the lock is not locked by anyone now, it went quiet.
         // Reset to zero so that it can be moved and initialized again for the next phase.
-        if !this.mutex_is_locked(&mutex_ref) {
+        if mutex_ref.owner().is_none() {
             let lock_place = this.deref_pointer_as(lock_op, this.machine.layouts.u32)?;
             this.write_scalar_atomic(Scalar::from_u32(0), &lock_place, AtomicWriteOrd::Relaxed)?;
         }
diff --git a/src/tools/miri/src/shims/unix/sync.rs b/src/tools/miri/src/shims/unix/sync.rs
index 9f1fabfbf64..eee2bbcb903 100644
--- a/src/tools/miri/src/shims/unix/sync.rs
+++ b/src/tools/miri/src/shims/unix/sync.rs
@@ -229,9 +229,9 @@ fn mutex_kind_from_static_initializer<'tcx>(
 // We store some data directly inside the type, ignoring the platform layout:
 // - init: u32
 
-#[derive(Debug, Copy, Clone)]
+#[derive(Debug, Clone)]
 struct PthreadRwLock {
-    id: RwLockId,
+    rwlock_ref: RwLockRef,
 }
 
 fn rwlock_init_offset<'tcx>(ecx: &MiriInterpCx<'tcx>) -> InterpResult<'tcx, Size> {
@@ -278,8 +278,8 @@ where
             )? {
                 throw_unsup_format!("unsupported static initializer used for `pthread_rwlock_t`");
             }
-            let id = ecx.machine.sync.rwlock_create();
-            interp_ok(PthreadRwLock { id })
+            let rwlock_ref = ecx.machine.sync.rwlock_create();
+            interp_ok(PthreadRwLock { rwlock_ref })
         },
     )
 }
@@ -504,11 +504,10 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
 
         let mutex = mutex_get_data(this, mutex_op)?.clone();
 
-        let ret = if this.mutex_is_locked(&mutex.mutex_ref) {
-            let owner_thread = this.mutex_get_owner(&mutex.mutex_ref);
+        let ret = if let Some(owner_thread) = mutex.mutex_ref.owner() {
             if owner_thread != this.active_thread() {
                 this.mutex_enqueue_and_block(
-                    &mutex.mutex_ref,
+                    mutex.mutex_ref,
                     Some((Scalar::from_i32(0), dest.clone())),
                 );
                 return interp_ok(());
@@ -541,8 +540,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
 
         let mutex = mutex_get_data(this, mutex_op)?.clone();
 
-        interp_ok(Scalar::from_i32(if this.mutex_is_locked(&mutex.mutex_ref) {
-            let owner_thread = this.mutex_get_owner(&mutex.mutex_ref);
+        interp_ok(Scalar::from_i32(if let Some(owner_thread) = mutex.mutex_ref.owner() {
             if owner_thread != this.active_thread() {
                 this.eval_libc_i32("EBUSY")
             } else {
@@ -596,7 +594,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
         // since we make the field uninit below.
         let mutex = mutex_get_data(this, mutex_op)?.clone();
 
-        if this.mutex_is_locked(&mutex.mutex_ref) {
+        if mutex.mutex_ref.owner().is_some() {
             throw_ub_format!("destroyed a locked mutex");
         }
 
@@ -616,12 +614,16 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
     ) -> InterpResult<'tcx> {
         let this = self.eval_context_mut();
 
-        let id = rwlock_get_data(this, rwlock_op)?.id;
+        let rwlock = rwlock_get_data(this, rwlock_op)?.clone();
 
-        if this.rwlock_is_write_locked(id) {
-            this.rwlock_enqueue_and_block_reader(id, Scalar::from_i32(0), dest.clone());
+        if rwlock.rwlock_ref.is_write_locked() {
+            this.rwlock_enqueue_and_block_reader(
+                rwlock.rwlock_ref,
+                Scalar::from_i32(0),
+                dest.clone(),
+            );
         } else {
-            this.rwlock_reader_lock(id);
+            this.rwlock_reader_lock(&rwlock.rwlock_ref);
             this.write_null(dest)?;
         }
 
@@ -631,12 +633,12 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
     fn pthread_rwlock_tryrdlock(&mut self, rwlock_op: &OpTy<'tcx>) -> InterpResult<'tcx, Scalar> {
         let this = self.eval_context_mut();
 
-        let id = rwlock_get_data(this, rwlock_op)?.id;
+        let rwlock = rwlock_get_data(this, rwlock_op)?.clone();
 
-        if this.rwlock_is_write_locked(id) {
+        if rwlock.rwlock_ref.is_write_locked() {
             interp_ok(Scalar::from_i32(this.eval_libc_i32("EBUSY")))
         } else {
-            this.rwlock_reader_lock(id);
+            this.rwlock_reader_lock(&rwlock.rwlock_ref);
             interp_ok(Scalar::from_i32(0))
         }
     }
@@ -648,9 +650,9 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
     ) -> InterpResult<'tcx> {
         let this = self.eval_context_mut();
 
-        let id = rwlock_get_data(this, rwlock_op)?.id;
+        let rwlock = rwlock_get_data(this, rwlock_op)?.clone();
 
-        if this.rwlock_is_locked(id) {
+        if rwlock.rwlock_ref.is_locked() {
             // Note: this will deadlock if the lock is already locked by this
             // thread in any way.
             //
@@ -663,9 +665,13 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
             // report the deadlock only when no thread can continue execution,
             // but we could detect that this lock is already locked and report
             // an error.)
-            this.rwlock_enqueue_and_block_writer(id, Scalar::from_i32(0), dest.clone());
+            this.rwlock_enqueue_and_block_writer(
+                rwlock.rwlock_ref,
+                Scalar::from_i32(0),
+                dest.clone(),
+            );
         } else {
-            this.rwlock_writer_lock(id);
+            this.rwlock_writer_lock(&rwlock.rwlock_ref);
             this.write_null(dest)?;
         }
 
@@ -675,12 +681,12 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
     fn pthread_rwlock_trywrlock(&mut self, rwlock_op: &OpTy<'tcx>) -> InterpResult<'tcx, Scalar> {
         let this = self.eval_context_mut();
 
-        let id = rwlock_get_data(this, rwlock_op)?.id;
+        let rwlock = rwlock_get_data(this, rwlock_op)?.clone();
 
-        if this.rwlock_is_locked(id) {
+        if rwlock.rwlock_ref.is_locked() {
             interp_ok(Scalar::from_i32(this.eval_libc_i32("EBUSY")))
         } else {
-            this.rwlock_writer_lock(id);
+            this.rwlock_writer_lock(&rwlock.rwlock_ref);
             interp_ok(Scalar::from_i32(0))
         }
     }
@@ -688,9 +694,11 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
     fn pthread_rwlock_unlock(&mut self, rwlock_op: &OpTy<'tcx>) -> InterpResult<'tcx, ()> {
         let this = self.eval_context_mut();
 
-        let id = rwlock_get_data(this, rwlock_op)?.id;
+        let rwlock = rwlock_get_data(this, rwlock_op)?.clone();
 
-        if this.rwlock_reader_unlock(id)? || this.rwlock_writer_unlock(id)? {
+        if this.rwlock_reader_unlock(&rwlock.rwlock_ref)?
+            || this.rwlock_writer_unlock(&rwlock.rwlock_ref)?
+        {
             interp_ok(())
         } else {
             throw_ub_format!("unlocked an rwlock that was not locked by the active thread");
@@ -702,9 +710,9 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
 
         // Reading the field also has the side-effect that we detect double-`destroy`
         // since we make the field uninit below.
-        let id = rwlock_get_data(this, rwlock_op)?.id;
+        let rwlock = rwlock_get_data(this, rwlock_op)?.clone();
 
-        if this.rwlock_is_locked(id) {
+        if rwlock.rwlock_ref.is_locked() {
             throw_ub_format!("destroyed a locked rwlock");
         }
 
diff --git a/src/tools/miri/tests/fail-dep/concurrency/apple_os_unfair_lock_assert_not_owner.stderr b/src/tools/miri/tests/fail-dep/concurrency/apple_os_unfair_lock_assert_not_owner.stderr
index 3fd02d38aae..27bee79177e 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/apple_os_unfair_lock_assert_not_owner.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/apple_os_unfair_lock_assert_not_owner.stderr
@@ -2,7 +2,7 @@ error: abnormal termination: called os_unfair_lock_assert_not_owner on an os_unf
   --> tests/fail-dep/concurrency/apple_os_unfair_lock_assert_not_owner.rs:LL:CC
    |
 LL |         libc::os_unfair_lock_assert_not_owner(lock.get());
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ called os_unfair_lock_assert_not_owner on an os_unfair_lock owned by the current thread
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ abnormal termination occurred here
    |
    = note: BACKTRACE:
    = note: inside `main` at tests/fail-dep/concurrency/apple_os_unfair_lock_assert_not_owner.rs:LL:CC
diff --git a/src/tools/miri/tests/fail-dep/concurrency/apple_os_unfair_lock_assert_owner.stderr b/src/tools/miri/tests/fail-dep/concurrency/apple_os_unfair_lock_assert_owner.stderr
index 0b5dfe4ba61..be53ee61c4c 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/apple_os_unfair_lock_assert_owner.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/apple_os_unfair_lock_assert_owner.stderr
@@ -2,7 +2,7 @@ error: abnormal termination: called os_unfair_lock_assert_owner on an os_unfair_
   --> tests/fail-dep/concurrency/apple_os_unfair_lock_assert_owner.rs:LL:CC
    |
 LL |         libc::os_unfair_lock_assert_owner(lock.get());
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ called os_unfair_lock_assert_owner on an os_unfair_lock not owned by the current thread
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ abnormal termination occurred here
    |
    = note: BACKTRACE:
    = note: inside `main` at tests/fail-dep/concurrency/apple_os_unfair_lock_assert_owner.rs:LL:CC
diff --git a/src/tools/miri/tests/fail-dep/concurrency/apple_os_unfair_lock_move_deadlock.stderr b/src/tools/miri/tests/fail-dep/concurrency/apple_os_unfair_lock_move_deadlock.stderr
index f043c7074f0..d00da6d6d9f 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/apple_os_unfair_lock_move_deadlock.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/apple_os_unfair_lock_move_deadlock.stderr
@@ -1,8 +1,8 @@
-error: deadlock: the evaluated program deadlocked
+error: the evaluated program deadlocked
   --> tests/fail-dep/concurrency/apple_os_unfair_lock_move_deadlock.rs:LL:CC
    |
 LL |     unsafe { libc::os_unfair_lock_lock(lock.get()) };
-   |                                                  ^ the evaluated program deadlocked
+   |                                                  ^ this thread got stuck here
    |
    = note: BACKTRACE:
    = note: inside `main` at tests/fail-dep/concurrency/apple_os_unfair_lock_move_deadlock.rs:LL:CC
diff --git a/src/tools/miri/tests/fail-dep/concurrency/apple_os_unfair_lock_reentrant.stderr b/src/tools/miri/tests/fail-dep/concurrency/apple_os_unfair_lock_reentrant.stderr
index 3b02936b1f2..08696a9b261 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/apple_os_unfair_lock_reentrant.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/apple_os_unfair_lock_reentrant.stderr
@@ -2,7 +2,7 @@ error: abnormal termination: attempted to lock an os_unfair_lock that is already
   --> tests/fail-dep/concurrency/apple_os_unfair_lock_reentrant.rs:LL:CC
    |
 LL |         libc::os_unfair_lock_lock(lock.get());
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ attempted to lock an os_unfair_lock that is already locked by the current thread
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ abnormal termination occurred here
    |
    = note: BACKTRACE:
    = note: inside `main` at tests/fail-dep/concurrency/apple_os_unfair_lock_reentrant.rs:LL:CC
diff --git a/src/tools/miri/tests/fail-dep/concurrency/apple_os_unfair_lock_unowned.stderr b/src/tools/miri/tests/fail-dep/concurrency/apple_os_unfair_lock_unowned.stderr
index 192e1cdc475..aaeb73176bf 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/apple_os_unfair_lock_unowned.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/apple_os_unfair_lock_unowned.stderr
@@ -2,7 +2,7 @@ error: abnormal termination: attempted to unlock an os_unfair_lock not owned by
   --> tests/fail-dep/concurrency/apple_os_unfair_lock_unowned.rs:LL:CC
    |
 LL |         libc::os_unfair_lock_unlock(lock.get());
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ attempted to unlock an os_unfair_lock not owned by the current thread
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ abnormal termination occurred here
    |
    = note: BACKTRACE:
    = note: inside `main` at tests/fail-dep/concurrency/apple_os_unfair_lock_unowned.rs:LL:CC
diff --git a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_cond_double_destroy.stderr b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_cond_double_destroy.stderr
index 4cf1b4af12a..7abdfa87f75 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_cond_double_destroy.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_cond_double_destroy.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: using uninitialized data, but this operation requires
   --> tests/fail-dep/concurrency/libc_pthread_cond_double_destroy.rs:LL:CC
    |
 LL |         libc::pthread_cond_destroy(cond.as_mut_ptr());
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ using uninitialized data, but this operation requires initialized memory
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_cond_move.init.stderr b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_cond_move.init.stderr
index 9a8ddc0b523..9a7f0bb79e5 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_cond_move.init.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_cond_move.init.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `pthread_cond_t` can't be moved after first use
   --> tests/fail-dep/concurrency/libc_pthread_cond_move.rs:LL:CC
    |
 LL |         libc::pthread_cond_destroy(cond2.as_mut_ptr());
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `pthread_cond_t` can't be moved after first use
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_cond_move.static_initializer.stderr b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_cond_move.static_initializer.stderr
index 8a7c0dee127..ee1fafcf7cb 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_cond_move.static_initializer.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_cond_move.static_initializer.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `pthread_cond_t` can't be moved after first use
   --> tests/fail-dep/concurrency/libc_pthread_cond_move.rs:LL:CC
    |
 LL |         libc::pthread_cond_destroy(&mut cond2 as *mut _);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `pthread_cond_t` can't be moved after first use
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_condattr_double_destroy.stderr b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_condattr_double_destroy.stderr
index f2ddf9ae92e..28a66253ae8 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_condattr_double_destroy.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_condattr_double_destroy.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: using uninitialized data, but this operation requires
   --> tests/fail-dep/concurrency/libc_pthread_condattr_double_destroy.rs:LL:CC
    |
 LL |         libc::pthread_condattr_destroy(attr.as_mut_ptr());
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ using uninitialized data, but this operation requires initialized memory
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_create_too_few_args.stderr b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_create_too_few_args.stderr
index aa67420c753..4fa8a430c51 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_create_too_few_args.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_create_too_few_args.stderr
@@ -1,6 +1,6 @@
 error: Undefined Behavior: calling a function with more arguments than it expected
    |
-   = note: calling a function with more arguments than it expected
+   = note: Undefined Behavior occurred here
    = note: (no span available)
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_create_too_many_args.stderr b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_create_too_many_args.stderr
index 4de947b1694..d28cba140fb 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_create_too_many_args.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_create_too_many_args.stderr
@@ -1,6 +1,6 @@
 error: Undefined Behavior: calling a function with fewer arguments than it requires
    |
-   = note: calling a function with fewer arguments than it requires
+   = note: Undefined Behavior occurred here
    = note: (no span available)
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_join_detached.stderr b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_join_detached.stderr
index 327737a0b3f..ffae90db2f9 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_join_detached.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_join_detached.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: trying to join a detached thread
   --> tests/fail-dep/concurrency/libc_pthread_join_detached.rs:LL:CC
    |
 LL |         assert_eq!(libc::pthread_join(native, ptr::null_mut()), 0);
-   |                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ trying to join a detached thread
+   |                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_join_joined.stderr b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_join_joined.stderr
index 1dd1cb9f731..354ad5dfc60 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_join_joined.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_join_joined.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: trying to join an already joined thread
   --> tests/fail-dep/concurrency/libc_pthread_join_joined.rs:LL:CC
    |
 LL |         assert_eq!(libc::pthread_join(native, ptr::null_mut()), 0);
-   |                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ trying to join an already joined thread
+   |                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_join_main.stderr b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_join_main.stderr
index b04a18561fd..41190f3f903 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_join_main.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_join_main.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: trying to join a detached thread
   --> tests/fail-dep/concurrency/libc_pthread_join_main.rs:LL:CC
    |
 LL |             assert_eq!(libc::pthread_join(thread_id, ptr::null_mut()), 0);
-   |                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ trying to join a detached thread
+   |                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_join_multiple.stderr b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_join_multiple.stderr
index 1ada476811e..a73dc20360a 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_join_multiple.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_join_multiple.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: trying to join an already joined thread
   --> tests/fail-dep/concurrency/libc_pthread_join_multiple.rs:LL:CC
    |
 LL | ...   assert_eq!(libc::pthread_join(native_copy, ptr::null_mut()), 0);
-   |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ trying to join an already joined thread
+   |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_join_self.stderr b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_join_self.stderr
index 6aa85086a83..e3082935c34 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_join_self.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_join_self.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: trying to join itself
   --> tests/fail-dep/concurrency/libc_pthread_join_self.rs:LL:CC
    |
 LL |             assert_eq!(libc::pthread_join(native, ptr::null_mut()), 0);
-   |                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ trying to join itself
+   |                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_NULL_reentrant.stderr b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_NULL_reentrant.stderr
index 9455e704376..961c541c70a 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_NULL_reentrant.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_NULL_reentrant.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: trying to acquire default mutex already locked by the
   --> tests/fail-dep/concurrency/libc_pthread_mutex_NULL_reentrant.rs:LL:CC
    |
 LL |         libc::pthread_mutex_lock(&mut mutex as *mut _);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ trying to acquire default mutex already locked by the current thread
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_deadlock.stderr b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_deadlock.stderr
index 534cacaed59..bcec5557a3f 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_deadlock.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_deadlock.stderr
@@ -1,17 +1,17 @@
-error: deadlock: the evaluated program deadlocked
+error: the evaluated program deadlocked
   --> tests/fail-dep/concurrency/libc_pthread_mutex_deadlock.rs:LL:CC
    |
 LL |             assert_eq!(libc::pthread_mutex_lock(lock_copy.0.get() as *mut _), 0);
-   |                                                                            ^ the evaluated program deadlocked
+   |                                                                            ^ this thread got stuck here
    |
    = note: BACKTRACE on thread `unnamed-ID`:
    = note: inside closure at tests/fail-dep/concurrency/libc_pthread_mutex_deadlock.rs:LL:CC
 
-error: deadlock: the evaluated program deadlocked
+error: the evaluated program deadlocked
   --> RUSTLIB/std/src/sys/pal/PLATFORM/thread.rs:LL:CC
    |
 LL |         let ret = unsafe { libc::pthread_join(id, ptr::null_mut()) };
-   |                                                                  ^ the evaluated program deadlocked
+   |                                                                  ^ this thread got stuck here
    |
    = note: BACKTRACE:
    = note: inside `std::sys::pal::PLATFORM::thread::Thread::join` at RUSTLIB/std/src/sys/pal/PLATFORM/thread.rs:LL:CC
diff --git a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_default_reentrant.stderr b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_default_reentrant.stderr
index a9ffbde1b65..743bb1af65c 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_default_reentrant.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_default_reentrant.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: trying to acquire default mutex already locked by the
   --> tests/fail-dep/concurrency/libc_pthread_mutex_default_reentrant.rs:LL:CC
    |
 LL |         libc::pthread_mutex_lock(&mut mutex as *mut _);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ trying to acquire default mutex already locked by the current thread
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_destroy_locked.stderr b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_destroy_locked.stderr
index 38f38b4283a..c4dce0ccc82 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_destroy_locked.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_destroy_locked.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: destroyed a locked mutex
   --> tests/fail-dep/concurrency/libc_pthread_mutex_destroy_locked.rs:LL:CC
    |
 LL |         libc::pthread_mutex_destroy(&mut mutex as *mut _);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ destroyed a locked mutex
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_double_destroy.stderr b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_double_destroy.stderr
index 72ad2db75aa..e7a6dee0203 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_double_destroy.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_double_destroy.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: using uninitialized data, but this operation requires
   --> tests/fail-dep/concurrency/libc_pthread_mutex_double_destroy.rs:LL:CC
    |
 LL |         libc::pthread_mutex_destroy(mutex.as_mut_ptr());
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ using uninitialized data, but this operation requires initialized memory
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_move.init.stderr b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_move.init.stderr
index 7df8e8be580..2e8e411e186 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_move.init.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_move.init.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `pthread_mutex_t` can't be moved after first use
   --> tests/fail-dep/concurrency/libc_pthread_mutex_move.rs:LL:CC
    |
 LL |         libc::pthread_mutex_lock(&mut m2 as *mut _);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `pthread_mutex_t` can't be moved after first use
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_move.static_initializer.stderr b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_move.static_initializer.stderr
index acc018cb4ba..4fd3bd52ae1 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_move.static_initializer.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_move.static_initializer.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `pthread_mutex_t` can't be moved after first use
   --> tests/fail-dep/concurrency/libc_pthread_mutex_move.rs:LL:CC
    |
 LL |         libc::pthread_mutex_unlock(&mut m2 as *mut _);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `pthread_mutex_t` can't be moved after first use
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_normal_reentrant.rs b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_normal_reentrant.rs
index 9a88639edf7..b88257992a5 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_normal_reentrant.rs
+++ b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_normal_reentrant.rs
@@ -12,6 +12,6 @@ fn main() {
         assert_eq!(libc::pthread_mutex_lock(&mut mutex as *mut _), 0);
         // A "normal" mutex properly tries to acquire the lock even if its is already held
         // by the current thread -- and then we deadlock.
-        libc::pthread_mutex_lock(&mut mutex as *mut _); //~ ERROR: deadlock: the evaluated program deadlocked
+        libc::pthread_mutex_lock(&mut mutex as *mut _); //~ ERROR: the evaluated program deadlocked
     }
 }
diff --git a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_normal_reentrant.stderr b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_normal_reentrant.stderr
index f20b26297e2..fa0c26f987e 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_normal_reentrant.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_normal_reentrant.stderr
@@ -1,8 +1,8 @@
-error: deadlock: the evaluated program deadlocked
+error: the evaluated program deadlocked
   --> tests/fail-dep/concurrency/libc_pthread_mutex_normal_reentrant.rs:LL:CC
    |
 LL |         libc::pthread_mutex_lock(&mut mutex as *mut _);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the evaluated program deadlocked
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ this thread got stuck here
    |
    = note: BACKTRACE:
    = note: inside `main` at tests/fail-dep/concurrency/libc_pthread_mutex_normal_reentrant.rs:LL:CC
diff --git a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_normal_unlock_unlocked.stderr b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_normal_unlock_unlocked.stderr
index db08496889e..7db3885d3d1 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_normal_unlock_unlocked.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_normal_unlock_unlocked.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: unlocked a PTHREAD_MUTEX_NORMAL mutex that was not lo
   --> tests/fail-dep/concurrency/libc_pthread_mutex_normal_unlock_unlocked.rs:LL:CC
    |
 LL |         libc::pthread_mutex_unlock(&mut mutex as *mut _);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ unlocked a PTHREAD_MUTEX_NORMAL mutex that was not locked by the current thread
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_staticinit_reentrant.stderr b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_staticinit_reentrant.stderr
index 984bb07b728..677955fe14d 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_staticinit_reentrant.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_staticinit_reentrant.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: trying to acquire default mutex already locked by the
   --> tests/fail-dep/concurrency/libc_pthread_mutex_staticinit_reentrant.rs:LL:CC
    |
 LL |         libc::pthread_mutex_lock(&mut mutex as *mut _);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ trying to acquire default mutex already locked by the current thread
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_wrong_owner.stderr b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_wrong_owner.stderr
index 97c92e828e6..4a70e16f37f 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_wrong_owner.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutex_wrong_owner.stderr
@@ -1,8 +1,8 @@
 error: Undefined Behavior: unlocked a default mutex that was not locked by the current thread
   --> tests/fail-dep/concurrency/libc_pthread_mutex_wrong_owner.rs:LL:CC
    |
-LL | ...t_eq!(libc::pthread_mutex_unlock(lock_copy.0.get() as *mut _), 0);
-   |          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ unlocked a default mutex that was not locked by the current thread
+LL | ...   assert_eq!(libc::pthread_mutex_unlock(lock_copy.0.get() as *mut _), 0);
+   |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutexattr_double_destroy.stderr b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutexattr_double_destroy.stderr
index 4c39ca003ec..0c9ee71de45 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutexattr_double_destroy.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_mutexattr_double_destroy.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: using uninitialized data, but this operation requires
   --> tests/fail-dep/concurrency/libc_pthread_mutexattr_double_destroy.rs:LL:CC
    |
 LL |         libc::pthread_mutexattr_destroy(attr.as_mut_ptr());
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ using uninitialized data, but this operation requires initialized memory
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_destroy_read_locked.stderr b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_destroy_read_locked.stderr
index 0a964da82a6..163d54a02f4 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_destroy_read_locked.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_destroy_read_locked.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: destroyed a locked rwlock
   --> tests/fail-dep/concurrency/libc_pthread_rwlock_destroy_read_locked.rs:LL:CC
    |
 LL |         libc::pthread_rwlock_destroy(rw.get());
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ destroyed a locked rwlock
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_destroy_write_locked.stderr b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_destroy_write_locked.stderr
index cfdadbefe4e..cc263552024 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_destroy_write_locked.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_destroy_write_locked.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: destroyed a locked rwlock
   --> tests/fail-dep/concurrency/libc_pthread_rwlock_destroy_write_locked.rs:LL:CC
    |
 LL |         libc::pthread_rwlock_destroy(rw.get());
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ destroyed a locked rwlock
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_double_destroy.stderr b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_double_destroy.stderr
index 41c189f3efd..836f0d060bd 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_double_destroy.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_double_destroy.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: using uninitialized data, but this operation requires
   --> tests/fail-dep/concurrency/libc_pthread_rwlock_double_destroy.rs:LL:CC
    |
 LL |         libc::pthread_rwlock_destroy(&mut lock);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ using uninitialized data, but this operation requires initialized memory
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_read_write_deadlock_single_thread.stderr b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_read_write_deadlock_single_thread.stderr
index 5b5d35bf195..c88d08de555 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_read_write_deadlock_single_thread.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_read_write_deadlock_single_thread.stderr
@@ -1,8 +1,8 @@
-error: deadlock: the evaluated program deadlocked
+error: the evaluated program deadlocked
   --> tests/fail-dep/concurrency/libc_pthread_rwlock_read_write_deadlock_single_thread.rs:LL:CC
    |
 LL |         libc::pthread_rwlock_wrlock(rw.get());
-   |                                             ^ the evaluated program deadlocked
+   |                                             ^ this thread got stuck here
    |
    = note: BACKTRACE:
    = note: inside `main` at tests/fail-dep/concurrency/libc_pthread_rwlock_read_write_deadlock_single_thread.rs:LL:CC
diff --git a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_read_wrong_owner.stderr b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_read_wrong_owner.stderr
index d2fccfcc3f0..85d8e0e8572 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_read_wrong_owner.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_read_wrong_owner.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: unlocked an rwlock that was not locked by the active
   --> tests/fail-dep/concurrency/libc_pthread_rwlock_read_wrong_owner.rs:LL:CC
    |
 LL | ...   assert_eq!(libc::pthread_rwlock_unlock(lock_copy.0.get() as *mut _), 0);
-   |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ unlocked an rwlock that was not locked by the active thread
+   |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_unlock_unlocked.stderr b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_unlock_unlocked.stderr
index da2a650151d..fc7bd8991e6 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_unlock_unlocked.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_unlock_unlocked.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: unlocked an rwlock that was not locked by the active
   --> tests/fail-dep/concurrency/libc_pthread_rwlock_unlock_unlocked.rs:LL:CC
    |
 LL |         libc::pthread_rwlock_unlock(rw.get());
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ unlocked an rwlock that was not locked by the active thread
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_write_read_deadlock.stderr b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_write_read_deadlock.stderr
index ae77d79fcd4..51533cd17a8 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_write_read_deadlock.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_write_read_deadlock.stderr
@@ -1,17 +1,17 @@
-error: deadlock: the evaluated program deadlocked
+error: the evaluated program deadlocked
   --> tests/fail-dep/concurrency/libc_pthread_rwlock_write_read_deadlock.rs:LL:CC
    |
 LL |             assert_eq!(libc::pthread_rwlock_wrlock(lock_copy.0.get() as *mut _), 0);
-   |                                                                               ^ the evaluated program deadlocked
+   |                                                                               ^ this thread got stuck here
    |
    = note: BACKTRACE on thread `unnamed-ID`:
    = note: inside closure at tests/fail-dep/concurrency/libc_pthread_rwlock_write_read_deadlock.rs:LL:CC
 
-error: deadlock: the evaluated program deadlocked
+error: the evaluated program deadlocked
   --> RUSTLIB/std/src/sys/pal/PLATFORM/thread.rs:LL:CC
    |
 LL |         let ret = unsafe { libc::pthread_join(id, ptr::null_mut()) };
-   |                                                                  ^ the evaluated program deadlocked
+   |                                                                  ^ this thread got stuck here
    |
    = note: BACKTRACE:
    = note: inside `std::sys::pal::PLATFORM::thread::Thread::join` at RUSTLIB/std/src/sys/pal/PLATFORM/thread.rs:LL:CC
diff --git a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_write_read_deadlock_single_thread.stderr b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_write_read_deadlock_single_thread.stderr
index 24c1a993652..d7d9a2d3686 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_write_read_deadlock_single_thread.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_write_read_deadlock_single_thread.stderr
@@ -1,8 +1,8 @@
-error: deadlock: the evaluated program deadlocked
+error: the evaluated program deadlocked
   --> tests/fail-dep/concurrency/libc_pthread_rwlock_write_read_deadlock_single_thread.rs:LL:CC
    |
 LL |         libc::pthread_rwlock_rdlock(rw.get());
-   |                                             ^ the evaluated program deadlocked
+   |                                             ^ this thread got stuck here
    |
    = note: BACKTRACE:
    = note: inside `main` at tests/fail-dep/concurrency/libc_pthread_rwlock_write_read_deadlock_single_thread.rs:LL:CC
diff --git a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_write_write_deadlock.stderr b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_write_write_deadlock.stderr
index 4f463464130..63fc7ce346e 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_write_write_deadlock.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_write_write_deadlock.stderr
@@ -1,17 +1,17 @@
-error: deadlock: the evaluated program deadlocked
+error: the evaluated program deadlocked
   --> tests/fail-dep/concurrency/libc_pthread_rwlock_write_write_deadlock.rs:LL:CC
    |
 LL |             assert_eq!(libc::pthread_rwlock_wrlock(lock_copy.0.get() as *mut _), 0);
-   |                                                                               ^ the evaluated program deadlocked
+   |                                                                               ^ this thread got stuck here
    |
    = note: BACKTRACE on thread `unnamed-ID`:
    = note: inside closure at tests/fail-dep/concurrency/libc_pthread_rwlock_write_write_deadlock.rs:LL:CC
 
-error: deadlock: the evaluated program deadlocked
+error: the evaluated program deadlocked
   --> RUSTLIB/std/src/sys/pal/PLATFORM/thread.rs:LL:CC
    |
 LL |         let ret = unsafe { libc::pthread_join(id, ptr::null_mut()) };
-   |                                                                  ^ the evaluated program deadlocked
+   |                                                                  ^ this thread got stuck here
    |
    = note: BACKTRACE:
    = note: inside `std::sys::pal::PLATFORM::thread::Thread::join` at RUSTLIB/std/src/sys/pal/PLATFORM/thread.rs:LL:CC
diff --git a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_write_write_deadlock_single_thread.stderr b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_write_write_deadlock_single_thread.stderr
index e76ce84e757..846f1e73d08 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_write_write_deadlock_single_thread.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_write_write_deadlock_single_thread.stderr
@@ -1,8 +1,8 @@
-error: deadlock: the evaluated program deadlocked
+error: the evaluated program deadlocked
   --> tests/fail-dep/concurrency/libc_pthread_rwlock_write_write_deadlock_single_thread.rs:LL:CC
    |
 LL |         libc::pthread_rwlock_wrlock(rw.get());
-   |                                             ^ the evaluated program deadlocked
+   |                                             ^ this thread got stuck here
    |
    = note: BACKTRACE:
    = note: inside `main` at tests/fail-dep/concurrency/libc_pthread_rwlock_write_write_deadlock_single_thread.rs:LL:CC
diff --git a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_write_wrong_owner.stderr b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_write_wrong_owner.stderr
index 906311144e8..8161b0e72eb 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_write_wrong_owner.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/libc_pthread_rwlock_write_wrong_owner.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: unlocked an rwlock that was not locked by the active
   --> tests/fail-dep/concurrency/libc_pthread_rwlock_write_wrong_owner.rs:LL:CC
    |
 LL | ...   assert_eq!(libc::pthread_rwlock_unlock(lock_copy.0.get() as *mut _), 0);
-   |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ unlocked an rwlock that was not locked by the active thread
+   |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/concurrency/libx_pthread_rwlock_moved.stderr b/src/tools/miri/tests/fail-dep/concurrency/libx_pthread_rwlock_moved.stderr
index fbc9119f110..77d99ed6b0f 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/libx_pthread_rwlock_moved.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/libx_pthread_rwlock_moved.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `pthread_rwlock_t` can't be moved after first use
   --> tests/fail-dep/concurrency/libx_pthread_rwlock_moved.rs:LL:CC
    |
 LL |         libc::pthread_rwlock_unlock(&mut rw2 as *mut _);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `pthread_rwlock_t` can't be moved after first use
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/concurrency/windows_join_detached.stderr b/src/tools/miri/tests/fail-dep/concurrency/windows_join_detached.stderr
index 947d665b95a..d8a3e058da9 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/windows_join_detached.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/windows_join_detached.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: trying to join a detached thread
   --> RUSTLIB/std/src/sys/pal/PLATFORM/thread.rs:LL:CC
    |
 LL |         let rc = unsafe { c::WaitForSingleObject(self.handle.as_raw_handle(), c::INFINITE) };
-   |                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ trying to join a detached thread
+   |                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/concurrency/windows_join_main.rs b/src/tools/miri/tests/fail-dep/concurrency/windows_join_main.rs
index 2980d257a29..da549a8d117 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/windows_join_main.rs
+++ b/src/tools/miri/tests/fail-dep/concurrency/windows_join_main.rs
@@ -18,7 +18,7 @@ const MAIN_THREAD: HANDLE = (2i32 << 29) as HANDLE;
 fn main() {
     thread::spawn(|| {
         unsafe {
-            assert_eq!(WaitForSingleObject(MAIN_THREAD, INFINITE), WAIT_OBJECT_0); //~ ERROR: deadlock: the evaluated program deadlocked
+            assert_eq!(WaitForSingleObject(MAIN_THREAD, INFINITE), WAIT_OBJECT_0); //~ ERROR: deadlock
         }
     })
     .join()
diff --git a/src/tools/miri/tests/fail-dep/concurrency/windows_join_main.stderr b/src/tools/miri/tests/fail-dep/concurrency/windows_join_main.stderr
index 6540543d8da..079f01c0e54 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/windows_join_main.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/windows_join_main.stderr
@@ -1,18 +1,18 @@
-error: deadlock: the evaluated program deadlocked
+error: the evaluated program deadlocked
   --> tests/fail-dep/concurrency/windows_join_main.rs:LL:CC
    |
 LL |             assert_eq!(WaitForSingleObject(MAIN_THREAD, INFINITE), WAIT_OBJECT_0);
-   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the evaluated program deadlocked
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ this thread got stuck here
    |
    = note: BACKTRACE on thread `unnamed-ID`:
    = note: inside closure at RUSTLIB/core/src/macros/mod.rs:LL:CC
    = note: this error originates in the macro `assert_eq` (in Nightly builds, run with -Z macro-backtrace for more info)
 
-error: deadlock: the evaluated program deadlocked
+error: the evaluated program deadlocked
   --> RUSTLIB/std/src/sys/pal/PLATFORM/thread.rs:LL:CC
    |
 LL |         let rc = unsafe { c::WaitForSingleObject(self.handle.as_raw_handle(), c::INFINITE) };
-   |                                                                                          ^ the evaluated program deadlocked
+   |                                                                                          ^ this thread got stuck here
    |
    = note: BACKTRACE:
    = note: inside `std::sys::pal::PLATFORM::thread::Thread::join` at RUSTLIB/std/src/sys/pal/PLATFORM/thread.rs:LL:CC
diff --git a/src/tools/miri/tests/fail-dep/concurrency/windows_join_self.rs b/src/tools/miri/tests/fail-dep/concurrency/windows_join_self.rs
index 85672ec860f..db3615ad34e 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/windows_join_self.rs
+++ b/src/tools/miri/tests/fail-dep/concurrency/windows_join_self.rs
@@ -14,7 +14,7 @@ fn main() {
     thread::spawn(|| {
         unsafe {
             let native = GetCurrentThread();
-            assert_eq!(WaitForSingleObject(native, INFINITE), WAIT_OBJECT_0); //~ ERROR: deadlock: the evaluated program deadlocked
+            assert_eq!(WaitForSingleObject(native, INFINITE), WAIT_OBJECT_0); //~ ERROR: deadlock
         }
     })
     .join()
diff --git a/src/tools/miri/tests/fail-dep/concurrency/windows_join_self.stderr b/src/tools/miri/tests/fail-dep/concurrency/windows_join_self.stderr
index 4e640296dbe..70de94f56ba 100644
--- a/src/tools/miri/tests/fail-dep/concurrency/windows_join_self.stderr
+++ b/src/tools/miri/tests/fail-dep/concurrency/windows_join_self.stderr
@@ -1,17 +1,17 @@
-error: deadlock: the evaluated program deadlocked
+error: the evaluated program deadlocked
   --> tests/fail-dep/concurrency/windows_join_self.rs:LL:CC
    |
 LL |             assert_eq!(WaitForSingleObject(native, INFINITE), WAIT_OBJECT_0);
-   |                                                            ^ the evaluated program deadlocked
+   |                                                            ^ this thread got stuck here
    |
    = note: BACKTRACE on thread `unnamed-ID`:
    = note: inside closure at tests/fail-dep/concurrency/windows_join_self.rs:LL:CC
 
-error: deadlock: the evaluated program deadlocked
+error: the evaluated program deadlocked
   --> RUSTLIB/std/src/sys/pal/PLATFORM/thread.rs:LL:CC
    |
 LL |         let rc = unsafe { c::WaitForSingleObject(self.handle.as_raw_handle(), c::INFINITE) };
-   |                                                                                          ^ the evaluated program deadlocked
+   |                                                                                          ^ this thread got stuck here
    |
    = note: BACKTRACE:
    = note: inside `std::sys::pal::PLATFORM::thread::Thread::join` at RUSTLIB/std/src/sys/pal/PLATFORM/thread.rs:LL:CC
diff --git a/src/tools/miri/tests/fail-dep/libc/affinity.stderr b/src/tools/miri/tests/fail-dep/libc/affinity.stderr
index cc3daa47e00..e0b3bf16601 100644
--- a/src/tools/miri/tests/fail-dep/libc/affinity.stderr
+++ b/src/tools/miri/tests/fail-dep/libc/affinity.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: memory access failed: attempting to access 129 bytes,
   --> tests/fail-dep/libc/affinity.rs:LL:CC
    |
 LL |     let err = unsafe { sched_setaffinity(PID, size_of::<cpu_set_t>() + 1, &cpuset) };
-   |                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ memory access failed: attempting to access 129 bytes, but got ALLOC which is only 128 bytes from the end of the allocation
+   |                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/libc/env-set_var-data-race.stderr b/src/tools/miri/tests/fail-dep/libc/env-set_var-data-race.stderr
index 904a1677b80..7db2338cc87 100644
--- a/src/tools/miri/tests/fail-dep/libc/env-set_var-data-race.stderr
+++ b/src/tools/miri/tests/fail-dep/libc/env-set_var-data-race.stderr
@@ -1,8 +1,8 @@
-error: Undefined Behavior: Data race detected between (1) non-atomic write on thread `main` and (2) non-atomic read on thread `unnamed-ID` at ALLOC. (2) just happened here
+error: Undefined Behavior: Data race detected between (1) non-atomic write on thread `main` and (2) non-atomic read on thread `unnamed-ID` at ALLOC
   --> tests/fail-dep/libc/env-set_var-data-race.rs:LL:CC
    |
 LL |         libc::getenv(b"TZ/0".as_ptr().cast());
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Data race detected between (1) non-atomic write on thread `main` and (2) non-atomic read on thread `unnamed-ID` at ALLOC. (2) just happened here
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ (2) just happened here
    |
 help: and (1) occurred earlier here
   --> tests/fail-dep/libc/env-set_var-data-race.rs:LL:CC
diff --git a/src/tools/miri/tests/fail-dep/libc/eventfd_block_read_twice.stderr b/src/tools/miri/tests/fail-dep/libc/eventfd_block_read_twice.stderr
index bb235345c5e..4f3a56fef82 100644
--- a/src/tools/miri/tests/fail-dep/libc/eventfd_block_read_twice.stderr
+++ b/src/tools/miri/tests/fail-dep/libc/eventfd_block_read_twice.stderr
@@ -1,8 +1,8 @@
-error: deadlock: the evaluated program deadlocked
+error: the evaluated program deadlocked
   --> RUSTLIB/std/src/sys/pal/PLATFORM/thread.rs:LL:CC
    |
 LL |         let ret = unsafe { libc::pthread_join(id, ptr::null_mut()) };
-   |                                                                  ^ the evaluated program deadlocked
+   |                                                                  ^ this thread got stuck here
    |
    = note: BACKTRACE:
    = note: inside `std::sys::pal::PLATFORM::thread::Thread::join` at RUSTLIB/std/src/sys/pal/PLATFORM/thread.rs:LL:CC
@@ -14,24 +14,24 @@ note: inside `main`
 LL |     thread2.join().unwrap();
    |     ^^^^^^^^^^^^^^
 
-error: deadlock: the evaluated program deadlocked
+error: the evaluated program deadlocked
    |
-   = note: the evaluated program deadlocked
+   = note: this thread got stuck here
    = note: (no span available)
    = note: BACKTRACE on thread `unnamed-ID`:
 
-error: deadlock: the evaluated program deadlocked
+error: the evaluated program deadlocked
   --> tests/fail-dep/libc/eventfd_block_read_twice.rs:LL:CC
    |
 LL |         let res: i64 = unsafe { libc::read(fd, buf.as_mut_ptr().cast(), 8).try_into().unwrap() };
-   |                                                                          ^ the evaluated program deadlocked
+   |                                                                          ^ this thread got stuck here
    |
    = note: BACKTRACE on thread `unnamed-ID`:
    = note: inside closure at tests/fail-dep/libc/eventfd_block_read_twice.rs:LL:CC
 
-error: deadlock: the evaluated program deadlocked
+error: the evaluated program deadlocked
    |
-   = note: the evaluated program deadlocked
+   = note: this thread got stuck here
    = note: (no span available)
    = note: BACKTRACE on thread `unnamed-ID`:
 
diff --git a/src/tools/miri/tests/fail-dep/libc/eventfd_block_write_twice.stderr b/src/tools/miri/tests/fail-dep/libc/eventfd_block_write_twice.stderr
index d9163a5748c..5045badaa87 100644
--- a/src/tools/miri/tests/fail-dep/libc/eventfd_block_write_twice.stderr
+++ b/src/tools/miri/tests/fail-dep/libc/eventfd_block_write_twice.stderr
@@ -1,8 +1,8 @@
-error: deadlock: the evaluated program deadlocked
+error: the evaluated program deadlocked
   --> RUSTLIB/std/src/sys/pal/PLATFORM/thread.rs:LL:CC
    |
 LL |         let ret = unsafe { libc::pthread_join(id, ptr::null_mut()) };
-   |                                                                  ^ the evaluated program deadlocked
+   |                                                                  ^ this thread got stuck here
    |
    = note: BACKTRACE:
    = note: inside `std::sys::pal::PLATFORM::thread::Thread::join` at RUSTLIB/std/src/sys/pal/PLATFORM/thread.rs:LL:CC
@@ -14,24 +14,24 @@ note: inside `main`
 LL |     thread2.join().unwrap();
    |     ^^^^^^^^^^^^^^
 
-error: deadlock: the evaluated program deadlocked
+error: the evaluated program deadlocked
    |
-   = note: the evaluated program deadlocked
+   = note: this thread got stuck here
    = note: (no span available)
    = note: BACKTRACE on thread `unnamed-ID`:
 
-error: deadlock: the evaluated program deadlocked
+error: the evaluated program deadlocked
   --> tests/fail-dep/libc/eventfd_block_write_twice.rs:LL:CC
    |
 LL |             libc::write(fd, sized_8_data.as_ptr() as *const libc::c_void, 8).try_into().unwrap()
-   |                                                                            ^ the evaluated program deadlocked
+   |                                                                            ^ this thread got stuck here
    |
    = note: BACKTRACE on thread `unnamed-ID`:
    = note: inside closure at tests/fail-dep/libc/eventfd_block_write_twice.rs:LL:CC
 
-error: deadlock: the evaluated program deadlocked
+error: the evaluated program deadlocked
    |
-   = note: the evaluated program deadlocked
+   = note: this thread got stuck here
    = note: (no span available)
    = note: BACKTRACE on thread `unnamed-ID`:
 
diff --git a/src/tools/miri/tests/fail-dep/libc/fcntl_fsetfl_while_blocking.rs b/src/tools/miri/tests/fail-dep/libc/fcntl_fsetfl_while_blocking.rs
index eef32136a0a..cfebb7c6435 100644
--- a/src/tools/miri/tests/fail-dep/libc/fcntl_fsetfl_while_blocking.rs
+++ b/src/tools/miri/tests/fail-dep/libc/fcntl_fsetfl_while_blocking.rs
@@ -1,5 +1,5 @@
 //@ignore-target: windows # Sockets/pipes are not implemented yet
-//~^ ERROR: deadlock: the evaluated program deadlocked
+//~^ ERROR: the evaluated program deadlocked
 //@compile-flags: -Zmiri-deterministic-concurrency
 use std::thread;
 
@@ -16,5 +16,5 @@ fn main() {
     });
     // Main thread will block on read.
     let _res = unsafe { libc::read(fds[0], buf.as_mut_ptr().cast(), buf.len() as libc::size_t) };
-    //~^ ERROR: deadlock: the evaluated program deadlocked
+    //~^ ERROR: the evaluated program deadlocked
 }
diff --git a/src/tools/miri/tests/fail-dep/libc/fcntl_fsetfl_while_blocking.stderr b/src/tools/miri/tests/fail-dep/libc/fcntl_fsetfl_while_blocking.stderr
index 9ca5598abae..41cfe78540a 100644
--- a/src/tools/miri/tests/fail-dep/libc/fcntl_fsetfl_while_blocking.stderr
+++ b/src/tools/miri/tests/fail-dep/libc/fcntl_fsetfl_while_blocking.stderr
@@ -1,14 +1,14 @@
-error: deadlock: the evaluated program deadlocked
+error: the evaluated program deadlocked
    |
-   = note: the evaluated program deadlocked
+   = note: this thread got stuck here
    = note: (no span available)
    = note: BACKTRACE on thread `unnamed-ID`:
 
-error: deadlock: the evaluated program deadlocked
+error: the evaluated program deadlocked
   --> tests/fail-dep/libc/fcntl_fsetfl_while_blocking.rs:LL:CC
    |
 LL |     let _res = unsafe { libc::read(fds[0], buf.as_mut_ptr().cast(), buf.len() as libc::size_t) };
-   |                                                                                              ^ the evaluated program deadlocked
+   |                                                                                              ^ this thread got stuck here
    |
    = note: BACKTRACE:
    = note: inside `main` at tests/fail-dep/libc/fcntl_fsetfl_while_blocking.rs:LL:CC
diff --git a/src/tools/miri/tests/fail-dep/libc/fs/close_stdout.stderr b/src/tools/miri/tests/fail-dep/libc/fs/close_stdout.stderr
index 029eeab4044..add7812c450 100644
--- a/src/tools/miri/tests/fail-dep/libc/fs/close_stdout.stderr
+++ b/src/tools/miri/tests/fail-dep/libc/fs/close_stdout.stderr
@@ -2,7 +2,7 @@ error: unsupported operation: cannot close stdout
   --> tests/fail-dep/libc/fs/close_stdout.rs:LL:CC
    |
 LL |         libc::close(1);
-   |         ^^^^^^^^^^^^^^ cannot close stdout
+   |         ^^^^^^^^^^^^^^ unsupported operation occurred here
    |
    = help: this is likely not a bug in the program; it indicates that the program performed an operation that Miri does not support
    = note: BACKTRACE:
diff --git a/src/tools/miri/tests/fail-dep/libc/fs/mkstemp_immutable_arg.stderr b/src/tools/miri/tests/fail-dep/libc/fs/mkstemp_immutable_arg.stderr
index 9227bddf5a8..981f055e129 100644
--- a/src/tools/miri/tests/fail-dep/libc/fs/mkstemp_immutable_arg.stderr
+++ b/src/tools/miri/tests/fail-dep/libc/fs/mkstemp_immutable_arg.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: writing to ALLOC which is read-only
   --> tests/fail-dep/libc/fs/mkstemp_immutable_arg.rs:LL:CC
    |
 LL |     let _fd = unsafe { libc::mkstemp(s) };
-   |                        ^^^^^^^^^^^^^^^^ writing to ALLOC which is read-only
+   |                        ^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/libc/fs/read_from_stdout.stderr b/src/tools/miri/tests/fail-dep/libc/fs/read_from_stdout.stderr
index 1be2f08dd8c..69dc59cd66d 100644
--- a/src/tools/miri/tests/fail-dep/libc/fs/read_from_stdout.stderr
+++ b/src/tools/miri/tests/fail-dep/libc/fs/read_from_stdout.stderr
@@ -2,7 +2,7 @@ error: unsupported operation: cannot read from stdout
   --> tests/fail-dep/libc/fs/read_from_stdout.rs:LL:CC
    |
 LL |         libc::read(1, bytes.as_mut_ptr() as *mut libc::c_void, 512);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ cannot read from stdout
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ unsupported operation occurred here
    |
    = help: this is likely not a bug in the program; it indicates that the program performed an operation that Miri does not support
    = note: BACKTRACE:
diff --git a/src/tools/miri/tests/fail-dep/libc/fs/unix_open_missing_required_mode.stderr b/src/tools/miri/tests/fail-dep/libc/fs/unix_open_missing_required_mode.stderr
index f48b75460d4..298e67f1468 100644
--- a/src/tools/miri/tests/fail-dep/libc/fs/unix_open_missing_required_mode.stderr
+++ b/src/tools/miri/tests/fail-dep/libc/fs/unix_open_missing_required_mode.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: not enough variadic arguments for `open(pathname, O_C
   --> tests/fail-dep/libc/fs/unix_open_missing_required_mode.rs:LL:CC
    |
 LL |     let _fd = unsafe { libc::open(name_ptr, libc::O_CREAT) };
-   |                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ not enough variadic arguments for `open(pathname, O_CREAT, ...)`: got 0, expected at least 1
+   |                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/libc/fs/write_to_stdin.stderr b/src/tools/miri/tests/fail-dep/libc/fs/write_to_stdin.stderr
index 9726a1d2a97..72f2c0e8662 100644
--- a/src/tools/miri/tests/fail-dep/libc/fs/write_to_stdin.stderr
+++ b/src/tools/miri/tests/fail-dep/libc/fs/write_to_stdin.stderr
@@ -2,7 +2,7 @@ error: unsupported operation: cannot write to stdin
   --> tests/fail-dep/libc/fs/write_to_stdin.rs:LL:CC
    |
 LL |         libc::write(0, bytes.as_ptr() as *const libc::c_void, 5);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ cannot write to stdin
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ unsupported operation occurred here
    |
    = help: this is likely not a bug in the program; it indicates that the program performed an operation that Miri does not support
    = note: BACKTRACE:
diff --git a/src/tools/miri/tests/fail-dep/libc/libc-epoll-data-race.stderr b/src/tools/miri/tests/fail-dep/libc/libc-epoll-data-race.stderr
index a16c86f90ed..ae1d6887cb3 100644
--- a/src/tools/miri/tests/fail-dep/libc/libc-epoll-data-race.stderr
+++ b/src/tools/miri/tests/fail-dep/libc/libc-epoll-data-race.stderr
@@ -1,8 +1,8 @@
-error: Undefined Behavior: Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) non-atomic read on thread `main` at ALLOC. (2) just happened here
+error: Undefined Behavior: Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) non-atomic read on thread `main` at ALLOC
   --> tests/fail-dep/libc/libc-epoll-data-race.rs:LL:CC
    |
 LL |         assert_eq!({ VAL_TWO }, 51)
-   |                      ^^^^^^^ Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) non-atomic read on thread `main` at ALLOC. (2) just happened here
+   |                      ^^^^^^^ (2) just happened here
    |
 help: and (1) occurred earlier here
   --> tests/fail-dep/libc/libc-epoll-data-race.rs:LL:CC
diff --git a/src/tools/miri/tests/fail-dep/libc/libc-read-and-uninit-premature-eof.stderr b/src/tools/miri/tests/fail-dep/libc/libc-read-and-uninit-premature-eof.stderr
index 980d9810abc..fadb31e3a8f 100644
--- a/src/tools/miri/tests/fail-dep/libc/libc-read-and-uninit-premature-eof.stderr
+++ b/src/tools/miri/tests/fail-dep/libc/libc-read-and-uninit-premature-eof.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value at .value[3]: encountered
   --> tests/fail-dep/libc/libc-read-and-uninit-premature-eof.rs:LL:CC
    |
 LL | ...   buf.assume_init();
-   |       ^^^^^^^^^^^^^^^^^ constructing invalid value at .value[3]: encountered uninitialized memory, but expected an integer
+   |       ^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/libc/libc_epoll_block_two_thread.stderr b/src/tools/miri/tests/fail-dep/libc/libc_epoll_block_two_thread.stderr
index b29794f68dd..3713c8da392 100644
--- a/src/tools/miri/tests/fail-dep/libc/libc_epoll_block_two_thread.stderr
+++ b/src/tools/miri/tests/fail-dep/libc/libc_epoll_block_two_thread.stderr
@@ -1,14 +1,14 @@
-error: deadlock: the evaluated program deadlocked
+error: the evaluated program deadlocked
    |
-   = note: the evaluated program deadlocked
+   = note: this thread got stuck here
    = note: (no span available)
    = note: BACKTRACE on thread `unnamed-ID`:
 
-error: deadlock: the evaluated program deadlocked
+error: the evaluated program deadlocked
   --> RUSTLIB/std/src/sys/pal/PLATFORM/thread.rs:LL:CC
    |
 LL |         let ret = unsafe { libc::pthread_join(id, ptr::null_mut()) };
-   |                                                                  ^ the evaluated program deadlocked
+   |                                                                  ^ this thread got stuck here
    |
    = note: BACKTRACE:
    = note: inside `std::sys::pal::PLATFORM::thread::Thread::join` at RUSTLIB/std/src/sys/pal/PLATFORM/thread.rs:LL:CC
@@ -20,18 +20,18 @@ note: inside `main`
 LL |     thread1.join().unwrap();
    |     ^^^^^^^^^^^^^^
 
-error: deadlock: the evaluated program deadlocked
+error: the evaluated program deadlocked
   --> tests/fail-dep/libc/libc_epoll_block_two_thread.rs:LL:CC
    |
 LL |         check_epoll_wait::<TAG>(epfd, &[(expected_event, expected_value)], -1);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the evaluated program deadlocked
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ this thread got stuck here
    |
    = note: BACKTRACE on thread `unnamed-ID`:
    = note: inside closure at tests/fail-dep/libc/libc_epoll_block_two_thread.rs:LL:CC
 
-error: deadlock: the evaluated program deadlocked
+error: the evaluated program deadlocked
    |
-   = note: the evaluated program deadlocked
+   = note: this thread got stuck here
    = note: (no span available)
    = note: BACKTRACE on thread `unnamed-ID`:
 
diff --git a/src/tools/miri/tests/fail-dep/libc/libc_epoll_unsupported_fd.stderr b/src/tools/miri/tests/fail-dep/libc/libc_epoll_unsupported_fd.stderr
index 59797145c20..2f02372472e 100644
--- a/src/tools/miri/tests/fail-dep/libc/libc_epoll_unsupported_fd.stderr
+++ b/src/tools/miri/tests/fail-dep/libc/libc_epoll_unsupported_fd.stderr
@@ -2,7 +2,7 @@ error: unsupported operation: epoll: epoll does not support this file descriptio
   --> tests/fail-dep/libc/libc_epoll_unsupported_fd.rs:LL:CC
    |
 LL |     let res = unsafe { libc::epoll_ctl(epfd0, libc::EPOLL_CTL_ADD, epfd1, &mut ev) };
-   |                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ epoll: epoll does not support this file description
+   |                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ unsupported operation occurred here
    |
    = help: this is likely not a bug in the program; it indicates that the program performed an operation that Miri does not support
    = note: BACKTRACE:
diff --git a/src/tools/miri/tests/fail-dep/libc/malloc_zero_double_free.stderr b/src/tools/miri/tests/fail-dep/libc/malloc_zero_double_free.stderr
index d6337c059ba..4895771acbe 100644
--- a/src/tools/miri/tests/fail-dep/libc/malloc_zero_double_free.stderr
+++ b/src/tools/miri/tests/fail-dep/libc/malloc_zero_double_free.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: memory access failed: ALLOC has been freed, so this p
   --> tests/fail-dep/libc/malloc_zero_double_free.rs:LL:CC
    |
 LL |         libc::free(ptr);
-   |         ^^^^^^^^^^^^^^^ memory access failed: ALLOC has been freed, so this pointer is dangling
+   |         ^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/libc/memchr_null.stderr b/src/tools/miri/tests/fail-dep/libc/memchr_null.stderr
index 5690277a046..e6fd3788033 100644
--- a/src/tools/miri/tests/fail-dep/libc/memchr_null.stderr
+++ b/src/tools/miri/tests/fail-dep/libc/memchr_null.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: pointer not dereferenceable: pointer must point to so
   --> tests/fail-dep/libc/memchr_null.rs:LL:CC
    |
 LL |         libc::memchr(ptr::null(), 0, 0);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ pointer not dereferenceable: pointer must point to some allocation, but got null pointer
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/libc/memcmp_null.stderr b/src/tools/miri/tests/fail-dep/libc/memcmp_null.stderr
index bd3a0719fa3..a80dec23c3a 100644
--- a/src/tools/miri/tests/fail-dep/libc/memcmp_null.stderr
+++ b/src/tools/miri/tests/fail-dep/libc/memcmp_null.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: pointer not dereferenceable: pointer must point to so
   --> tests/fail-dep/libc/memcmp_null.rs:LL:CC
    |
 LL |         libc::memcmp(ptr::null(), ptr::null(), 0);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ pointer not dereferenceable: pointer must point to some allocation, but got null pointer
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/libc/memcmp_zero.stderr b/src/tools/miri/tests/fail-dep/libc/memcmp_zero.stderr
index 2044c154761..8b114703b33 100644
--- a/src/tools/miri/tests/fail-dep/libc/memcmp_zero.stderr
+++ b/src/tools/miri/tests/fail-dep/libc/memcmp_zero.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: pointer not dereferenceable: pointer must point to so
   --> tests/fail-dep/libc/memcmp_zero.rs:LL:CC
    |
 LL |         libc::memcmp(ptr.cast(), ptr.cast(), 0);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ pointer not dereferenceable: pointer must point to some allocation, but got 0x2a[noalloc] which is a dangling pointer (it has no provenance)
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/libc/memcpy_zero.stderr b/src/tools/miri/tests/fail-dep/libc/memcpy_zero.stderr
index 789e9daf43b..4c95e47fd22 100644
--- a/src/tools/miri/tests/fail-dep/libc/memcpy_zero.stderr
+++ b/src/tools/miri/tests/fail-dep/libc/memcpy_zero.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: pointer not dereferenceable: pointer must point to so
   --> tests/fail-dep/libc/memcpy_zero.rs:LL:CC
    |
 LL |         libc::memcpy(to.cast(), from.cast(), 0);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ pointer not dereferenceable: pointer must point to some allocation, but got 0x17[noalloc] which is a dangling pointer (it has no provenance)
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/libc/memrchr_null.stderr b/src/tools/miri/tests/fail-dep/libc/memrchr_null.stderr
index 27e7a9855d1..1a162681420 100644
--- a/src/tools/miri/tests/fail-dep/libc/memrchr_null.stderr
+++ b/src/tools/miri/tests/fail-dep/libc/memrchr_null.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: pointer not dereferenceable: pointer must point to so
   --> tests/fail-dep/libc/memrchr_null.rs:LL:CC
    |
 LL |         libc::memrchr(ptr::null(), 0, 0);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ pointer not dereferenceable: pointer must point to some allocation, but got null pointer
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/libc/mmap_invalid_dealloc.stderr b/src/tools/miri/tests/fail-dep/libc/mmap_invalid_dealloc.stderr
index 193c9f1eccc..ed9e5ebc29e 100644
--- a/src/tools/miri/tests/fail-dep/libc/mmap_invalid_dealloc.stderr
+++ b/src/tools/miri/tests/fail-dep/libc/mmap_invalid_dealloc.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: deallocating ALLOC, which is mmap memory, using C hea
   --> tests/fail-dep/libc/mmap_invalid_dealloc.rs:LL:CC
    |
 LL |         libc::free(ptr);
-   |         ^^^^^^^^^^^^^^^ deallocating ALLOC, which is mmap memory, using C heap deallocation operation
+   |         ^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/libc/mmap_use_after_munmap.stderr b/src/tools/miri/tests/fail-dep/libc/mmap_use_after_munmap.stderr
index 8404aeb5a7a..f25e74477a5 100644
--- a/src/tools/miri/tests/fail-dep/libc/mmap_use_after_munmap.stderr
+++ b/src/tools/miri/tests/fail-dep/libc/mmap_use_after_munmap.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: memory access failed: ALLOC has been freed, so this p
   --> tests/fail-dep/libc/mmap_use_after_munmap.rs:LL:CC
    |
 LL |         let _x = *(ptr as *mut u8);
-   |                  ^^^^^^^^^^^^^^^^^ memory access failed: ALLOC has been freed, so this pointer is dangling
+   |                  ^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/libc/munmap_partial.stderr b/src/tools/miri/tests/fail-dep/libc/munmap_partial.stderr
index 7b1703a968a..e1caf4a2dce 100644
--- a/src/tools/miri/tests/fail-dep/libc/munmap_partial.stderr
+++ b/src/tools/miri/tests/fail-dep/libc/munmap_partial.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: incorrect layout on deallocation: ALLOC has size SIZE
   --> tests/fail-dep/libc/munmap_partial.rs:LL:CC
    |
 LL |         libc::munmap(ptr, 1);
-   |         ^^^^^^^^^^^^^^^^^^^^ incorrect layout on deallocation: ALLOC has size SIZE and alignment ALIGN, but gave size SIZE and alignment ALIGN
+   |         ^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/libc/posix_memalign_size_zero_double_free.stderr b/src/tools/miri/tests/fail-dep/libc/posix_memalign_size_zero_double_free.stderr
index 1d73ec95754..9e3b861998a 100644
--- a/src/tools/miri/tests/fail-dep/libc/posix_memalign_size_zero_double_free.stderr
+++ b/src/tools/miri/tests/fail-dep/libc/posix_memalign_size_zero_double_free.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: memory access failed: ALLOC has been freed, so this p
   --> tests/fail-dep/libc/posix_memalign_size_zero_double_free.rs:LL:CC
    |
 LL |         libc::free(ptr);
-   |         ^^^^^^^^^^^^^^^ memory access failed: ALLOC has been freed, so this pointer is dangling
+   |         ^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/libc/realloc-zero.stderr b/src/tools/miri/tests/fail-dep/libc/realloc-zero.stderr
index 6f8095dbba1..45964551146 100644
--- a/src/tools/miri/tests/fail-dep/libc/realloc-zero.stderr
+++ b/src/tools/miri/tests/fail-dep/libc/realloc-zero.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `realloc` with a size of zero
   --> tests/fail-dep/libc/realloc-zero.rs:LL:CC
    |
 LL |         let p2 = libc::realloc(p1, 0);
-   |                  ^^^^^^^^^^^^^^^^^^^^ `realloc` with a size of zero
+   |                  ^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail-dep/libc/socketpair-close-while-blocked.stderr b/src/tools/miri/tests/fail-dep/libc/socketpair-close-while-blocked.stderr
index fe196f5d7d7..47fc889b001 100644
--- a/src/tools/miri/tests/fail-dep/libc/socketpair-close-while-blocked.stderr
+++ b/src/tools/miri/tests/fail-dep/libc/socketpair-close-while-blocked.stderr
@@ -1,8 +1,8 @@
-error: deadlock: the evaluated program deadlocked
+error: the evaluated program deadlocked
   --> RUSTLIB/std/src/sys/pal/PLATFORM/thread.rs:LL:CC
    |
 LL |         let ret = unsafe { libc::pthread_join(id, ptr::null_mut()) };
-   |                                                                  ^ the evaluated program deadlocked
+   |                                                                  ^ this thread got stuck here
    |
    = note: BACKTRACE:
    = note: inside `std::sys::pal::PLATFORM::thread::Thread::join` at RUSTLIB/std/src/sys/pal/PLATFORM/thread.rs:LL:CC
@@ -14,18 +14,18 @@ note: inside `main`
 LL |     thread1.join().unwrap();
    |     ^^^^^^^^^^^^^^
 
-error: deadlock: the evaluated program deadlocked
+error: the evaluated program deadlocked
   --> tests/fail-dep/libc/socketpair-close-while-blocked.rs:LL:CC
    |
 LL |             libc::read(fds[1], buf.as_mut_ptr().cast(), buf.len() as libc::size_t)
-   |                                                                                  ^ the evaluated program deadlocked
+   |                                                                                  ^ this thread got stuck here
    |
    = note: BACKTRACE on thread `unnamed-ID`:
    = note: inside closure at tests/fail-dep/libc/socketpair-close-while-blocked.rs:LL:CC
 
-error: deadlock: the evaluated program deadlocked
+error: the evaluated program deadlocked
    |
-   = note: the evaluated program deadlocked
+   = note: this thread got stuck here
    = note: (no span available)
    = note: BACKTRACE on thread `unnamed-ID`:
 
diff --git a/src/tools/miri/tests/fail-dep/libc/socketpair-data-race.stderr b/src/tools/miri/tests/fail-dep/libc/socketpair-data-race.stderr
index 6472c33727c..7fb08fe6f10 100644
--- a/src/tools/miri/tests/fail-dep/libc/socketpair-data-race.stderr
+++ b/src/tools/miri/tests/fail-dep/libc/socketpair-data-race.stderr
@@ -1,8 +1,8 @@
-error: Undefined Behavior: Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) non-atomic read on thread `main` at ALLOC. (2) just happened here
+error: Undefined Behavior: Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) non-atomic read on thread `main` at ALLOC
   --> tests/fail-dep/libc/socketpair-data-race.rs:LL:CC
    |
 LL |     unsafe { assert_eq!({ VAL }, 1) };
-   |                           ^^^ Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) non-atomic read on thread `main` at ALLOC. (2) just happened here
+   |                           ^^^ (2) just happened here
    |
 help: and (1) occurred earlier here
   --> tests/fail-dep/libc/socketpair-data-race.rs:LL:CC
diff --git a/src/tools/miri/tests/fail-dep/libc/socketpair_block_read_twice.stderr b/src/tools/miri/tests/fail-dep/libc/socketpair_block_read_twice.stderr
index ab807a579db..9f19a60e6ae 100644
--- a/src/tools/miri/tests/fail-dep/libc/socketpair_block_read_twice.stderr
+++ b/src/tools/miri/tests/fail-dep/libc/socketpair_block_read_twice.stderr
@@ -1,8 +1,8 @@
-error: deadlock: the evaluated program deadlocked
+error: the evaluated program deadlocked
   --> RUSTLIB/std/src/sys/pal/PLATFORM/thread.rs:LL:CC
    |
 LL |         let ret = unsafe { libc::pthread_join(id, ptr::null_mut()) };
-   |                                                                  ^ the evaluated program deadlocked
+   |                                                                  ^ this thread got stuck here
    |
    = note: BACKTRACE:
    = note: inside `std::sys::pal::PLATFORM::thread::Thread::join` at RUSTLIB/std/src/sys/pal/PLATFORM/thread.rs:LL:CC
@@ -14,24 +14,24 @@ note: inside `main`
 LL |     thread2.join().unwrap();
    |     ^^^^^^^^^^^^^^
 
-error: deadlock: the evaluated program deadlocked
+error: the evaluated program deadlocked
    |
-   = note: the evaluated program deadlocked
+   = note: this thread got stuck here
    = note: (no span available)
    = note: BACKTRACE on thread `unnamed-ID`:
 
-error: deadlock: the evaluated program deadlocked
+error: the evaluated program deadlocked
   --> tests/fail-dep/libc/socketpair_block_read_twice.rs:LL:CC
    |
 LL |         let res = unsafe { libc::read(fds[1], buf.as_mut_ptr().cast(), buf.len() as libc::size_t) };
-   |                                                                                                 ^ the evaluated program deadlocked
+   |                                                                                                 ^ this thread got stuck here
    |
    = note: BACKTRACE on thread `unnamed-ID`:
    = note: inside closure at tests/fail-dep/libc/socketpair_block_read_twice.rs:LL:CC
 
-error: deadlock: the evaluated program deadlocked
+error: the evaluated program deadlocked
    |
-   = note: the evaluated program deadlocked
+   = note: this thread got stuck here
    = note: (no span available)
    = note: BACKTRACE on thread `unnamed-ID`:
 
diff --git a/src/tools/miri/tests/fail-dep/libc/socketpair_block_write_twice.stderr b/src/tools/miri/tests/fail-dep/libc/socketpair_block_write_twice.stderr
index 44cda11102d..b29cd70f35e 100644
--- a/src/tools/miri/tests/fail-dep/libc/socketpair_block_write_twice.stderr
+++ b/src/tools/miri/tests/fail-dep/libc/socketpair_block_write_twice.stderr
@@ -1,8 +1,8 @@
-error: deadlock: the evaluated program deadlocked
+error: the evaluated program deadlocked
   --> RUSTLIB/std/src/sys/pal/PLATFORM/thread.rs:LL:CC
    |
 LL |         let ret = unsafe { libc::pthread_join(id, ptr::null_mut()) };
-   |                                                                  ^ the evaluated program deadlocked
+   |                                                                  ^ this thread got stuck here
    |
    = note: BACKTRACE:
    = note: inside `std::sys::pal::PLATFORM::thread::Thread::join` at RUSTLIB/std/src/sys/pal/PLATFORM/thread.rs:LL:CC
@@ -14,24 +14,24 @@ note: inside `main`
 LL |     thread2.join().unwrap();
    |     ^^^^^^^^^^^^^^
 
-error: deadlock: the evaluated program deadlocked
+error: the evaluated program deadlocked
    |
-   = note: the evaluated program deadlocked
+   = note: this thread got stuck here
    = note: (no span available)
    = note: BACKTRACE on thread `unnamed-ID`:
 
-error: deadlock: the evaluated program deadlocked
+error: the evaluated program deadlocked
   --> tests/fail-dep/libc/socketpair_block_write_twice.rs:LL:CC
    |
 LL |         let res = unsafe { libc::write(fds[0], data as *const libc::c_void, 3) };
-   |                                                                              ^ the evaluated program deadlocked
+   |                                                                              ^ this thread got stuck here
    |
    = note: BACKTRACE on thread `unnamed-ID`:
    = note: inside closure at tests/fail-dep/libc/socketpair_block_write_twice.rs:LL:CC
 
-error: deadlock: the evaluated program deadlocked
+error: the evaluated program deadlocked
    |
-   = note: the evaluated program deadlocked
+   = note: this thread got stuck here
    = note: (no span available)
    = note: BACKTRACE on thread `unnamed-ID`:
 
diff --git a/src/tools/miri/tests/fail-dep/libc/unsupported_incomplete_function.stderr b/src/tools/miri/tests/fail-dep/libc/unsupported_incomplete_function.stderr
index 52a93ab263d..161cb383cf7 100644
--- a/src/tools/miri/tests/fail-dep/libc/unsupported_incomplete_function.stderr
+++ b/src/tools/miri/tests/fail-dep/libc/unsupported_incomplete_function.stderr
@@ -2,7 +2,7 @@ error: unsupported operation: can't call foreign function `signal` on $OS
   --> tests/fail-dep/libc/unsupported_incomplete_function.rs:LL:CC
    |
 LL |         libc::signal(libc::SIGPIPE, libc::SIG_IGN);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ can't call foreign function `signal` on $OS
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ unsupported operation occurred here
    |
    = help: this means the program tried to do something Miri does not support; it does not indicate a bug in the program
    = note: BACKTRACE:
diff --git a/src/tools/miri/tests/fail/alloc/alloc_error_handler.stderr b/src/tools/miri/tests/fail/alloc/alloc_error_handler.stderr
index fa84da841fd..d67dabd6935 100644
--- a/src/tools/miri/tests/fail/alloc/alloc_error_handler.stderr
+++ b/src/tools/miri/tests/fail/alloc/alloc_error_handler.stderr
@@ -3,7 +3,7 @@ error: abnormal termination: the program aborted execution
   --> RUSTLIB/std/src/sys/pal/PLATFORM/mod.rs:LL:CC
    |
 LL | ABORT()
-   | ^ the program aborted execution
+   | ^ abnormal termination occurred here
    |
    = note: BACKTRACE:
    = note: inside `std::sys::pal::PLATFORM::abort_internal` at RUSTLIB/std/src/sys/pal/PLATFORM/mod.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/alloc/alloc_error_handler_custom.stderr b/src/tools/miri/tests/fail/alloc/alloc_error_handler_custom.stderr
index 7e8c198b6a3..29c56ca81f7 100644
--- a/src/tools/miri/tests/fail/alloc/alloc_error_handler_custom.stderr
+++ b/src/tools/miri/tests/fail/alloc/alloc_error_handler_custom.stderr
@@ -3,7 +3,7 @@ error: abnormal termination: the program aborted execution
   --> tests/fail/alloc/alloc_error_handler_custom.rs:LL:CC
    |
 LL |     core::intrinsics::abort();
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^ the program aborted execution
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^ abnormal termination occurred here
    |
    = note: BACKTRACE:
    = note: inside `alloc_error_handler` at tests/fail/alloc/alloc_error_handler_custom.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/alloc/alloc_error_handler_no_std.stderr b/src/tools/miri/tests/fail/alloc/alloc_error_handler_no_std.stderr
index 6b4266b9a8b..45ba366acae 100644
--- a/src/tools/miri/tests/fail/alloc/alloc_error_handler_no_std.stderr
+++ b/src/tools/miri/tests/fail/alloc/alloc_error_handler_no_std.stderr
@@ -5,7 +5,7 @@ error: abnormal termination: the program aborted execution
   --> tests/fail/alloc/alloc_error_handler_no_std.rs:LL:CC
    |
 LL |     core::intrinsics::abort();
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^ the program aborted execution
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^ abnormal termination occurred here
    |
    = note: BACKTRACE:
    = note: inside `panic_handler` at tests/fail/alloc/alloc_error_handler_no_std.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/alloc/deallocate-bad-alignment.stderr b/src/tools/miri/tests/fail/alloc/deallocate-bad-alignment.stderr
index f07db3c62c9..11e1eaa3852 100644
--- a/src/tools/miri/tests/fail/alloc/deallocate-bad-alignment.stderr
+++ b/src/tools/miri/tests/fail/alloc/deallocate-bad-alignment.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: incorrect layout on deallocation: ALLOC has size 1 an
   --> tests/fail/alloc/deallocate-bad-alignment.rs:LL:CC
    |
 LL |         dealloc(x, Layout::from_size_align_unchecked(1, 2));
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ incorrect layout on deallocation: ALLOC has size 1 and alignment ALIGN, but gave size 1 and alignment ALIGN
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/alloc/deallocate-bad-size.stderr b/src/tools/miri/tests/fail/alloc/deallocate-bad-size.stderr
index c913bde04cc..5e0e2f2da44 100644
--- a/src/tools/miri/tests/fail/alloc/deallocate-bad-size.stderr
+++ b/src/tools/miri/tests/fail/alloc/deallocate-bad-size.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: incorrect layout on deallocation: ALLOC has size 1 an
   --> tests/fail/alloc/deallocate-bad-size.rs:LL:CC
    |
 LL |         dealloc(x, Layout::from_size_align_unchecked(2, 1));
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ incorrect layout on deallocation: ALLOC has size 1 and alignment ALIGN, but gave size 2 and alignment ALIGN
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/alloc/deallocate-twice.stderr b/src/tools/miri/tests/fail/alloc/deallocate-twice.stderr
index 9e6ce3d45a7..715fe7b0f60 100644
--- a/src/tools/miri/tests/fail/alloc/deallocate-twice.stderr
+++ b/src/tools/miri/tests/fail/alloc/deallocate-twice.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: memory access failed: ALLOC has been freed, so this p
   --> tests/fail/alloc/deallocate-twice.rs:LL:CC
    |
 LL |         dealloc(x, Layout::from_size_align_unchecked(1, 1));
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ memory access failed: ALLOC has been freed, so this pointer is dangling
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/alloc/global_system_mixup.stderr b/src/tools/miri/tests/fail/alloc/global_system_mixup.stderr
index 4c355c511ef..5a5f7496237 100644
--- a/src/tools/miri/tests/fail/alloc/global_system_mixup.stderr
+++ b/src/tools/miri/tests/fail/alloc/global_system_mixup.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: deallocating ALLOC, which is Rust heap memory, using
   --> RUSTLIB/std/src/sys/alloc/PLATFORM.rs:LL:CC
    |
 LL |         FREE();
-   | ^ deallocating ALLOC, which is Rust heap memory, using PLATFORM heap deallocation operation
+   | ^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/alloc/no_global_allocator.stderr b/src/tools/miri/tests/fail/alloc/no_global_allocator.stderr
index e80a3646714..b2b688e0c9e 100644
--- a/src/tools/miri/tests/fail/alloc/no_global_allocator.stderr
+++ b/src/tools/miri/tests/fail/alloc/no_global_allocator.stderr
@@ -2,7 +2,7 @@ error: unsupported operation: can't call foreign function `__rust_alloc` on $OS
   --> tests/fail/alloc/no_global_allocator.rs:LL:CC
    |
 LL |         __rust_alloc(1, 1);
-   |         ^^^^^^^^^^^^^^^^^^ can't call foreign function `__rust_alloc` on $OS
+   |         ^^^^^^^^^^^^^^^^^^ unsupported operation occurred here
    |
    = help: this means the program tried to do something Miri does not support; it does not indicate a bug in the program
    = note: BACKTRACE:
diff --git a/src/tools/miri/tests/fail/alloc/reallocate-bad-size.stderr b/src/tools/miri/tests/fail/alloc/reallocate-bad-size.stderr
index 6f6c8850603..639ed069f08 100644
--- a/src/tools/miri/tests/fail/alloc/reallocate-bad-size.stderr
+++ b/src/tools/miri/tests/fail/alloc/reallocate-bad-size.stderr
@@ -1,8 +1,8 @@
 error: Undefined Behavior: incorrect layout on deallocation: ALLOC has size 1 and alignment ALIGN, but gave size 2 and alignment ALIGN
   --> tests/fail/alloc/reallocate-bad-size.rs:LL:CC
    |
-LL |         let _y = realloc(x, Layout::from_size_align_unchecked(2, 1), 1);
-   |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ incorrect layout on deallocation: ALLOC has size 1 and alignment ALIGN, but gave size 2 and alignment ALIGN
+LL | ...   let _y = realloc(x, Layout::from_size_align_unchecked(2, 1), 1);
+   |                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/alloc/reallocate-change-alloc.stderr b/src/tools/miri/tests/fail/alloc/reallocate-change-alloc.stderr
index 17b40fbdcdc..16e6a5b5b09 100644
--- a/src/tools/miri/tests/fail/alloc/reallocate-change-alloc.stderr
+++ b/src/tools/miri/tests/fail/alloc/reallocate-change-alloc.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: memory access failed: ALLOC has been freed, so this p
   --> tests/fail/alloc/reallocate-change-alloc.rs:LL:CC
    |
 LL |         let _z = *x;
-   |                  ^^ memory access failed: ALLOC has been freed, so this pointer is dangling
+   |                  ^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/alloc/reallocate-dangling.stderr b/src/tools/miri/tests/fail/alloc/reallocate-dangling.stderr
index 06960380f6c..e30a02ef9d7 100644
--- a/src/tools/miri/tests/fail/alloc/reallocate-dangling.stderr
+++ b/src/tools/miri/tests/fail/alloc/reallocate-dangling.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: memory access failed: ALLOC has been freed, so this p
   --> tests/fail/alloc/reallocate-dangling.rs:LL:CC
    |
 LL |         let _z = realloc(x, Layout::from_size_align_unchecked(1, 1), 1);
-   |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ memory access failed: ALLOC has been freed, so this pointer is dangling
+   |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/alloc/stack_free.stderr b/src/tools/miri/tests/fail/alloc/stack_free.stderr
index 7d7cee133c6..6e98a7abc76 100644
--- a/src/tools/miri/tests/fail/alloc/stack_free.stderr
+++ b/src/tools/miri/tests/fail/alloc/stack_free.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: deallocating ALLOC, which is stack variable memory, u
   --> RUSTLIB/alloc/src/boxed.rs:LL:CC
    |
 LL |                 self.1.deallocate(From::from(ptr.cast()), layout);
-   |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ deallocating ALLOC, which is stack variable memory, using Rust heap deallocation operation
+   |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/alloc/too_large.stderr b/src/tools/miri/tests/fail/alloc/too_large.stderr
index 03e54088e3b..dcfaeb737a8 100644
--- a/src/tools/miri/tests/fail/alloc/too_large.stderr
+++ b/src/tools/miri/tests/fail/alloc/too_large.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: creating an allocation larger than half the address s
   --> tests/fail/alloc/too_large.rs:LL:CC
    |
 LL |         __rust_alloc(bytes, 1);
-   |         ^^^^^^^^^^^^^^^^^^^^^^ creating an allocation larger than half the address space
+   |         ^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/alloc/unsupported_big_alignment.stderr b/src/tools/miri/tests/fail/alloc/unsupported_big_alignment.stderr
index 8eb71f5ce84..6c7ee17df35 100644
--- a/src/tools/miri/tests/fail/alloc/unsupported_big_alignment.stderr
+++ b/src/tools/miri/tests/fail/alloc/unsupported_big_alignment.stderr
@@ -2,7 +2,7 @@ error: unsupported operation: creating allocation with alignment ALIGN exceeding
   --> tests/fail/alloc/unsupported_big_alignment.rs:LL:CC
    |
 LL |         __rust_alloc(1, 1 << 30);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^ creating allocation with alignment ALIGN exceeding rustc's maximum supported value
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^ unsupported operation occurred here
    |
    = help: this is likely not a bug in the program; it indicates that the program performed an operation that Miri does not support
    = note: BACKTRACE:
diff --git a/src/tools/miri/tests/fail/alloc/unsupported_non_power_two_alignment.stderr b/src/tools/miri/tests/fail/alloc/unsupported_non_power_two_alignment.stderr
index 0a36d3d58b6..a0f853a4291 100644
--- a/src/tools/miri/tests/fail/alloc/unsupported_non_power_two_alignment.stderr
+++ b/src/tools/miri/tests/fail/alloc/unsupported_non_power_two_alignment.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: creating allocation with non-power-of-two alignment A
   --> tests/fail/alloc/unsupported_non_power_two_alignment.rs:LL:CC
    |
 LL |         __rust_alloc(1, 3);
-   |         ^^^^^^^^^^^^^^^^^^ creating allocation with non-power-of-two alignment ALIGN
+   |         ^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/async-shared-mutable.stack.stderr b/src/tools/miri/tests/fail/async-shared-mutable.stack.stderr
index 8f53a55cc3e..bc3db8c6801 100644
--- a/src/tools/miri/tests/fail/async-shared-mutable.stack.stderr
+++ b/src/tools/miri/tests/fail/async-shared-mutable.stack.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: attempting a write access using <TAG> at ALLOC[OFFSET
   --> tests/fail/async-shared-mutable.rs:LL:CC
    |
 LL |             *x = 1;
-   |             ^^^^^^
-   |             |
-   |             attempting a write access using <TAG> at ALLOC[OFFSET], but that tag does not exist in the borrow stack for this location
-   |             this error occurs as part of an access at ALLOC[OFFSET]
+   |             ^^^^^^ this error occurs as part of an access at ALLOC[OFFSET]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/async-shared-mutable.tree.stderr b/src/tools/miri/tests/fail/async-shared-mutable.tree.stderr
index d1e66a0d043..17efb10ceb0 100644
--- a/src/tools/miri/tests/fail/async-shared-mutable.tree.stderr
+++ b/src/tools/miri/tests/fail/async-shared-mutable.tree.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: write access through <TAG> at ALLOC[OFFSET] is forbid
   --> tests/fail/async-shared-mutable.rs:LL:CC
    |
 LL |             *x = 1;
-   |             ^^^^^^ write access through <TAG> at ALLOC[OFFSET] is forbidden
+   |             ^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> has state Frozen which forbids this child write access
diff --git a/src/tools/miri/tests/fail/both_borrows/alias_through_mutation.stack.stderr b/src/tools/miri/tests/fail/both_borrows/alias_through_mutation.stack.stderr
index d7e7c2bc039..70301db0fbb 100644
--- a/src/tools/miri/tests/fail/both_borrows/alias_through_mutation.stack.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/alias_through_mutation.stack.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: attempting a read access using <TAG> at ALLOC[0x0], b
   --> tests/fail/both_borrows/alias_through_mutation.rs:LL:CC
    |
 LL |     let _val = *target_alias;
-   |                ^^^^^^^^^^^^^
-   |                |
-   |                attempting a read access using <TAG> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
-   |                this error occurs as part of an access at ALLOC[0x0..0x4]
+   |                ^^^^^^^^^^^^^ this error occurs as part of an access at ALLOC[0x0..0x4]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/both_borrows/alias_through_mutation.tree.stderr b/src/tools/miri/tests/fail/both_borrows/alias_through_mutation.tree.stderr
index c146658d310..9e992f88f0c 100644
--- a/src/tools/miri/tests/fail/both_borrows/alias_through_mutation.tree.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/alias_through_mutation.tree.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: read access through <TAG> at ALLOC[0x0] is forbidden
   --> tests/fail/both_borrows/alias_through_mutation.rs:LL:CC
    |
 LL |     let _val = *target_alias;
-   |                ^^^^^^^^^^^^^ read access through <TAG> at ALLOC[0x0] is forbidden
+   |                ^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> has state Disabled which forbids this child read access
diff --git a/src/tools/miri/tests/fail/both_borrows/aliasing_mut1.stack.stderr b/src/tools/miri/tests/fail/both_borrows/aliasing_mut1.stack.stderr
index 170027d9f90..b7fdc7bc414 100644
--- a/src/tools/miri/tests/fail/both_borrows/aliasing_mut1.stack.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/aliasing_mut1.stack.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: not granting access to tag <TAG> because that would r
   --> tests/fail/both_borrows/aliasing_mut1.rs:LL:CC
    |
 LL | pub fn safe(x: &mut i32, y: &mut i32) {
-   |                          ^ not granting access to tag <TAG> because that would remove [Unique for <TAG>] which is strongly protected
+   |                          ^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/both_borrows/aliasing_mut1.tree.stderr b/src/tools/miri/tests/fail/both_borrows/aliasing_mut1.tree.stderr
index 62ab1c4f872..e331ff2406d 100644
--- a/src/tools/miri/tests/fail/both_borrows/aliasing_mut1.tree.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/aliasing_mut1.tree.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: write access through <TAG> at ALLOC[0x0] is forbidden
   --> tests/fail/both_borrows/aliasing_mut1.rs:LL:CC
    |
 LL |     *x = 1;
-   |     ^^^^^^ write access through <TAG> at ALLOC[0x0] is forbidden
+   |     ^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> has state Reserved (conflicted) which forbids this child write access
diff --git a/src/tools/miri/tests/fail/both_borrows/aliasing_mut2.stack.stderr b/src/tools/miri/tests/fail/both_borrows/aliasing_mut2.stack.stderr
index 274dc22a7e1..a13cbec6655 100644
--- a/src/tools/miri/tests/fail/both_borrows/aliasing_mut2.stack.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/aliasing_mut2.stack.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: not granting access to tag <TAG> because that would r
   --> tests/fail/both_borrows/aliasing_mut2.rs:LL:CC
    |
 LL | pub fn safe(x: &i32, y: &mut i32) {
-   |                      ^ not granting access to tag <TAG> because that would remove [SharedReadOnly for <TAG>] which is strongly protected
+   |                      ^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/both_borrows/aliasing_mut2.tree.stderr b/src/tools/miri/tests/fail/both_borrows/aliasing_mut2.tree.stderr
index f3d7a016825..a2191da0b4f 100644
--- a/src/tools/miri/tests/fail/both_borrows/aliasing_mut2.tree.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/aliasing_mut2.tree.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: write access through <TAG> at ALLOC[0x0] is forbidden
   --> tests/fail/both_borrows/aliasing_mut2.rs:LL:CC
    |
 LL |     *y = 2;
-   |     ^^^^^^ write access through <TAG> at ALLOC[0x0] is forbidden
+   |     ^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> has state Reserved (conflicted) which forbids this child write access
diff --git a/src/tools/miri/tests/fail/both_borrows/aliasing_mut3.stack.stderr b/src/tools/miri/tests/fail/both_borrows/aliasing_mut3.stack.stderr
index a89baa50ff3..0e9382be2e8 100644
--- a/src/tools/miri/tests/fail/both_borrows/aliasing_mut3.stack.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/aliasing_mut3.stack.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: trying to retag from <TAG> for SharedReadOnly permiss
   --> tests/fail/both_borrows/aliasing_mut3.rs:LL:CC
    |
 LL | pub fn safe(x: &mut i32, y: &i32) {
-   |                          ^
-   |                          |
-   |                          trying to retag from <TAG> for SharedReadOnly permission at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
-   |                          this error occurs as part of function-entry retag at ALLOC[0x0..0x4]
+   |                          ^ this error occurs as part of function-entry retag at ALLOC[0x0..0x4]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/both_borrows/aliasing_mut3.tree.stderr b/src/tools/miri/tests/fail/both_borrows/aliasing_mut3.tree.stderr
index ba9197a50d6..e92cad1777b 100644
--- a/src/tools/miri/tests/fail/both_borrows/aliasing_mut3.tree.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/aliasing_mut3.tree.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: write access through <TAG> at ALLOC[0x0] is forbidden
   --> tests/fail/both_borrows/aliasing_mut3.rs:LL:CC
    |
 LL |     *x = 1;
-   |     ^^^^^^ write access through <TAG> at ALLOC[0x0] is forbidden
+   |     ^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> has state Reserved (conflicted) which forbids this child write access
diff --git a/src/tools/miri/tests/fail/both_borrows/aliasing_mut4.stack.stderr b/src/tools/miri/tests/fail/both_borrows/aliasing_mut4.stack.stderr
index bdda7139490..c5ad269b39a 100644
--- a/src/tools/miri/tests/fail/both_borrows/aliasing_mut4.stack.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/aliasing_mut4.stack.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: not granting access to tag <TAG> because that would r
   --> tests/fail/both_borrows/aliasing_mut4.rs:LL:CC
    |
 LL | pub fn safe(x: &i32, y: &mut Cell<i32>) {
-   |                      ^ not granting access to tag <TAG> because that would remove [SharedReadOnly for <TAG>] which is strongly protected
+   |                      ^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/both_borrows/aliasing_mut4.tree.stderr b/src/tools/miri/tests/fail/both_borrows/aliasing_mut4.tree.stderr
index e8babf02163..e195b0a7e87 100644
--- a/src/tools/miri/tests/fail/both_borrows/aliasing_mut4.tree.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/aliasing_mut4.tree.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: write access through <TAG> at ALLOC[0x0] is forbidden
   --> RUSTLIB/core/src/mem/mod.rs:LL:CC
    |
 LL |         crate::intrinsics::write_via_move(dest, src);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ write access through <TAG> at ALLOC[0x0] is forbidden
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> is foreign to the protected tag <TAG> (i.e., it is not a child)
diff --git a/src/tools/miri/tests/fail/both_borrows/box_exclusive_violation1.stack.stderr b/src/tools/miri/tests/fail/both_borrows/box_exclusive_violation1.stack.stderr
index 0cffdcd21c4..009ec2dd4aa 100644
--- a/src/tools/miri/tests/fail/both_borrows/box_exclusive_violation1.stack.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/box_exclusive_violation1.stack.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: attempting a write access using <TAG> at ALLOC[0x0],
   --> tests/fail/both_borrows/box_exclusive_violation1.rs:LL:CC
    |
 LL |         *LEAK = 7;
-   |         ^^^^^^^^^
-   |         |
-   |         attempting a write access using <TAG> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
-   |         this error occurs as part of an access at ALLOC[0x0..0x4]
+   |         ^^^^^^^^^ this error occurs as part of an access at ALLOC[0x0..0x4]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/both_borrows/box_exclusive_violation1.tree.stderr b/src/tools/miri/tests/fail/both_borrows/box_exclusive_violation1.tree.stderr
index 075df9982c6..30832ae60ac 100644
--- a/src/tools/miri/tests/fail/both_borrows/box_exclusive_violation1.tree.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/box_exclusive_violation1.tree.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: write access through <TAG> at ALLOC[0x0] is forbidden
   --> tests/fail/both_borrows/box_exclusive_violation1.rs:LL:CC
    |
 LL |         *LEAK = 7;
-   |         ^^^^^^^^^ write access through <TAG> at ALLOC[0x0] is forbidden
+   |         ^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> has state Disabled which forbids this child write access
diff --git a/src/tools/miri/tests/fail/both_borrows/box_noalias_violation.stack.stderr b/src/tools/miri/tests/fail/both_borrows/box_noalias_violation.stack.stderr
index 3dc3f8c6619..cc6633eb24f 100644
--- a/src/tools/miri/tests/fail/both_borrows/box_noalias_violation.stack.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/box_noalias_violation.stack.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: not granting access to tag <TAG> because that would r
   --> tests/fail/both_borrows/box_noalias_violation.rs:LL:CC
    |
 LL |     *y
-   |     ^^ not granting access to tag <TAG> because that would remove [Unique for <TAG>] which is weakly protected
+   |     ^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/both_borrows/box_noalias_violation.tree.stderr b/src/tools/miri/tests/fail/both_borrows/box_noalias_violation.tree.stderr
index c788e455c8d..d7b865d57a8 100644
--- a/src/tools/miri/tests/fail/both_borrows/box_noalias_violation.tree.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/box_noalias_violation.tree.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: read access through <TAG> at ALLOC[0x0] is forbidden
   --> tests/fail/both_borrows/box_noalias_violation.rs:LL:CC
    |
 LL |     *y
-   |     ^^ read access through <TAG> at ALLOC[0x0] is forbidden
+   |     ^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> is foreign to the protected tag <TAG> (i.e., it is not a child)
diff --git a/src/tools/miri/tests/fail/both_borrows/buggy_as_mut_slice.stack.stderr b/src/tools/miri/tests/fail/both_borrows/buggy_as_mut_slice.stack.stderr
index 4e5355f5653..2e394297b0c 100644
--- a/src/tools/miri/tests/fail/both_borrows/buggy_as_mut_slice.stack.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/buggy_as_mut_slice.stack.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: attempting a write access using <TAG> at ALLOC[0x4],
   --> tests/fail/both_borrows/buggy_as_mut_slice.rs:LL:CC
    |
 LL |     v1[1] = 5;
-   |     ^^^^^^^^^
-   |     |
-   |     attempting a write access using <TAG> at ALLOC[0x4], but that tag does not exist in the borrow stack for this location
-   |     this error occurs as part of an access at ALLOC[0x4..0x8]
+   |     ^^^^^^^^^ this error occurs as part of an access at ALLOC[0x4..0x8]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/both_borrows/buggy_as_mut_slice.tree.stderr b/src/tools/miri/tests/fail/both_borrows/buggy_as_mut_slice.tree.stderr
index bad42343c00..ad5df3399c8 100644
--- a/src/tools/miri/tests/fail/both_borrows/buggy_as_mut_slice.tree.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/buggy_as_mut_slice.tree.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: write access through <TAG> at ALLOC[0x4] is forbidden
   --> tests/fail/both_borrows/buggy_as_mut_slice.rs:LL:CC
    |
 LL |     v2[1] = 7;
-   |     ^^^^^^^^^ write access through <TAG> at ALLOC[0x4] is forbidden
+   |     ^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> has state Disabled which forbids this child write access
diff --git a/src/tools/miri/tests/fail/both_borrows/buggy_split_at_mut.stack.stderr b/src/tools/miri/tests/fail/both_borrows/buggy_split_at_mut.stack.stderr
index 28be7607aa3..c4cb2c7ae4d 100644
--- a/src/tools/miri/tests/fail/both_borrows/buggy_split_at_mut.stack.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/buggy_split_at_mut.stack.stderr
@@ -7,7 +7,6 @@ LL | |                 from_raw_parts_mut(ptr.offset(mid as isize), len - mid),
 LL | |             )
    | |             ^
    | |             |
-   | |             trying to retag from <TAG> for Unique permission at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
    | |_____________this error occurs as part of retag (of a reference/box inside this compound value) at ALLOC[0x0..0x10]
    |               errors for retagging in fields are fairly new; please reach out to us (e.g. at <https://rust-lang.zulipchat.com/#narrow/stream/269128-miri>) if you find this error troubling
    |
diff --git a/src/tools/miri/tests/fail/both_borrows/buggy_split_at_mut.tree.stderr b/src/tools/miri/tests/fail/both_borrows/buggy_split_at_mut.tree.stderr
index c734f257a40..4ab49e75adb 100644
--- a/src/tools/miri/tests/fail/both_borrows/buggy_split_at_mut.tree.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/buggy_split_at_mut.tree.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: write access through <TAG> at ALLOC[0x4] is forbidden
   --> tests/fail/both_borrows/buggy_split_at_mut.rs:LL:CC
    |
 LL |     b[1] = 6;
-   |     ^^^^^^^^ write access through <TAG> at ALLOC[0x4] is forbidden
+   |     ^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> has state Disabled which forbids this child write access
diff --git a/src/tools/miri/tests/fail/both_borrows/illegal_write1.stack.stderr b/src/tools/miri/tests/fail/both_borrows/illegal_write1.stack.stderr
index 9df441cb956..55046dbbe67 100644
--- a/src/tools/miri/tests/fail/both_borrows/illegal_write1.stack.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/illegal_write1.stack.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: attempting a write access using <TAG> at ALLOC[0x0],
   --> tests/fail/both_borrows/illegal_write1.rs:LL:CC
    |
 LL |         unsafe { *x = 42 };
-   |                  ^^^^^^^
-   |                  |
-   |                  attempting a write access using <TAG> at ALLOC[0x0], but that tag only grants SharedReadOnly permission for this location
-   |                  this error occurs as part of an access at ALLOC[0x0..0x4]
+   |                  ^^^^^^^ this error occurs as part of an access at ALLOC[0x0..0x4]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/both_borrows/illegal_write1.tree.stderr b/src/tools/miri/tests/fail/both_borrows/illegal_write1.tree.stderr
index cd415ad6de9..b718e19ff5a 100644
--- a/src/tools/miri/tests/fail/both_borrows/illegal_write1.tree.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/illegal_write1.tree.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: write access through <TAG> at ALLOC[0x0] is forbidden
   --> tests/fail/both_borrows/illegal_write1.rs:LL:CC
    |
 LL |         unsafe { *x = 42 };
-   |                  ^^^^^^^ write access through <TAG> at ALLOC[0x0] is forbidden
+   |                  ^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> has state Frozen which forbids this child write access
diff --git a/src/tools/miri/tests/fail/both_borrows/illegal_write5.stack.stderr b/src/tools/miri/tests/fail/both_borrows/illegal_write5.stack.stderr
index 2a517941de5..4e39d9c083b 100644
--- a/src/tools/miri/tests/fail/both_borrows/illegal_write5.stack.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/illegal_write5.stack.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: attempting a read access using <TAG> at ALLOC[0x0], b
   --> tests/fail/both_borrows/illegal_write5.rs:LL:CC
    |
 LL |     let _val = *xref;
-   |                ^^^^^
-   |                |
-   |                attempting a read access using <TAG> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
-   |                this error occurs as part of an access at ALLOC[0x0..0x4]
+   |                ^^^^^ this error occurs as part of an access at ALLOC[0x0..0x4]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/both_borrows/illegal_write5.tree.stderr b/src/tools/miri/tests/fail/both_borrows/illegal_write5.tree.stderr
index 38bc957cc33..d4c78c4bd33 100644
--- a/src/tools/miri/tests/fail/both_borrows/illegal_write5.tree.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/illegal_write5.tree.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: read access through <TAG> at ALLOC[0x0] is forbidden
   --> tests/fail/both_borrows/illegal_write5.rs:LL:CC
    |
 LL |     let _val = *xref;
-   |                ^^^^^ read access through <TAG> at ALLOC[0x0] is forbidden
+   |                ^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> has state Disabled which forbids this child read access
diff --git a/src/tools/miri/tests/fail/both_borrows/illegal_write6.stack.stderr b/src/tools/miri/tests/fail/both_borrows/illegal_write6.stack.stderr
index e75334508ff..40b44d77e3d 100644
--- a/src/tools/miri/tests/fail/both_borrows/illegal_write6.stack.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/illegal_write6.stack.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: not granting access to tag <TAG> because that would r
   --> tests/fail/both_borrows/illegal_write6.rs:LL:CC
    |
 LL |     unsafe { *y = 2 };
-   |              ^^^^^^ not granting access to tag <TAG> because that would remove [Unique for <TAG>] which is strongly protected
+   |              ^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/both_borrows/illegal_write6.tree.stderr b/src/tools/miri/tests/fail/both_borrows/illegal_write6.tree.stderr
index 31599a767cf..e537bc18c05 100644
--- a/src/tools/miri/tests/fail/both_borrows/illegal_write6.tree.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/illegal_write6.tree.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: write access through <TAG> at ALLOC[0x0] is forbidden
   --> tests/fail/both_borrows/illegal_write6.rs:LL:CC
    |
 LL |     unsafe { *y = 2 };
-   |              ^^^^^^ write access through <TAG> at ALLOC[0x0] is forbidden
+   |              ^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> is foreign to the protected tag <TAG> (i.e., it is not a child)
diff --git a/src/tools/miri/tests/fail/both_borrows/invalidate_against_protector2.stack.stderr b/src/tools/miri/tests/fail/both_borrows/invalidate_against_protector2.stack.stderr
index b5df1653289..ef531be496a 100644
--- a/src/tools/miri/tests/fail/both_borrows/invalidate_against_protector2.stack.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/invalidate_against_protector2.stack.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: not granting access to tag <TAG> because that would r
   --> tests/fail/both_borrows/invalidate_against_protector2.rs:LL:CC
    |
 LL |     unsafe { *x = 0 };
-   |              ^^^^^^ not granting access to tag <TAG> because that would remove [SharedReadOnly for <TAG>] which is strongly protected
+   |              ^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/both_borrows/invalidate_against_protector2.tree.stderr b/src/tools/miri/tests/fail/both_borrows/invalidate_against_protector2.tree.stderr
index c3b836a8aa7..af90e75d384 100644
--- a/src/tools/miri/tests/fail/both_borrows/invalidate_against_protector2.tree.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/invalidate_against_protector2.tree.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: write access through <TAG> at ALLOC[0x0] is forbidden
   --> tests/fail/both_borrows/invalidate_against_protector2.rs:LL:CC
    |
 LL |     unsafe { *x = 0 };
-   |              ^^^^^^ write access through <TAG> at ALLOC[0x0] is forbidden
+   |              ^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> is foreign to the protected tag <TAG> (i.e., it is not a child)
diff --git a/src/tools/miri/tests/fail/both_borrows/invalidate_against_protector3.stack.stderr b/src/tools/miri/tests/fail/both_borrows/invalidate_against_protector3.stack.stderr
index 0010ce0e4ed..caf2b702fec 100644
--- a/src/tools/miri/tests/fail/both_borrows/invalidate_against_protector3.stack.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/invalidate_against_protector3.stack.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: not granting access to tag <TAG> because that would r
   --> tests/fail/both_borrows/invalidate_against_protector3.rs:LL:CC
    |
 LL |     unsafe { *x = 0 };
-   |              ^^^^^^ not granting access to tag <TAG> because that would remove [SharedReadOnly for <TAG>] which is strongly protected
+   |              ^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/both_borrows/invalidate_against_protector3.tree.stderr b/src/tools/miri/tests/fail/both_borrows/invalidate_against_protector3.tree.stderr
index b47fb81f5f4..5d5f5e59ead 100644
--- a/src/tools/miri/tests/fail/both_borrows/invalidate_against_protector3.tree.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/invalidate_against_protector3.tree.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: write access through <TAG> (root of the allocation) a
   --> tests/fail/both_borrows/invalidate_against_protector3.rs:LL:CC
    |
 LL |     unsafe { *x = 0 };
-   |              ^^^^^^ write access through <TAG> (root of the allocation) at ALLOC[0x0] is forbidden
+   |              ^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> (root of the allocation) is foreign to the protected tag <TAG> (i.e., it is not a child)
diff --git a/src/tools/miri/tests/fail/both_borrows/issue-miri-1050-1.stack.stderr b/src/tools/miri/tests/fail/both_borrows/issue-miri-1050-1.stack.stderr
index 0e6d838dfff..9927d90c646 100644
--- a/src/tools/miri/tests/fail/both_borrows/issue-miri-1050-1.stack.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/issue-miri-1050-1.stack.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: pointer not dereferenceable: pointer must be derefere
   --> RUSTLIB/alloc/src/boxed.rs:LL:CC
    |
 LL |         Box(unsafe { Unique::new_unchecked(raw) }, alloc)
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ pointer not dereferenceable: pointer must be dereferenceable for 4 bytes, but got ALLOC which is only 2 bytes from the end of the allocation
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/both_borrows/issue-miri-1050-1.tree.stderr b/src/tools/miri/tests/fail/both_borrows/issue-miri-1050-1.tree.stderr
index 0e6d838dfff..9927d90c646 100644
--- a/src/tools/miri/tests/fail/both_borrows/issue-miri-1050-1.tree.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/issue-miri-1050-1.tree.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: pointer not dereferenceable: pointer must be derefere
   --> RUSTLIB/alloc/src/boxed.rs:LL:CC
    |
 LL |         Box(unsafe { Unique::new_unchecked(raw) }, alloc)
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ pointer not dereferenceable: pointer must be dereferenceable for 4 bytes, but got ALLOC which is only 2 bytes from the end of the allocation
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/both_borrows/issue-miri-1050-2.stack.stderr b/src/tools/miri/tests/fail/both_borrows/issue-miri-1050-2.stack.stderr
index 861173f5496..c704085f958 100644
--- a/src/tools/miri/tests/fail/both_borrows/issue-miri-1050-2.stack.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/issue-miri-1050-2.stack.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: pointer not dereferenceable: pointer must be derefere
   --> RUSTLIB/alloc/src/boxed.rs:LL:CC
    |
 LL |         Box(unsafe { Unique::new_unchecked(raw) }, alloc)
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ pointer not dereferenceable: pointer must be dereferenceable for 4 bytes, but got 0x4[noalloc] which is a dangling pointer (it has no provenance)
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/both_borrows/issue-miri-1050-2.tree.stderr b/src/tools/miri/tests/fail/both_borrows/issue-miri-1050-2.tree.stderr
index 861173f5496..c704085f958 100644
--- a/src/tools/miri/tests/fail/both_borrows/issue-miri-1050-2.tree.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/issue-miri-1050-2.tree.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: pointer not dereferenceable: pointer must be derefere
   --> RUSTLIB/alloc/src/boxed.rs:LL:CC
    |
 LL |         Box(unsafe { Unique::new_unchecked(raw) }, alloc)
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ pointer not dereferenceable: pointer must be dereferenceable for 4 bytes, but got 0x4[noalloc] which is a dangling pointer (it has no provenance)
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/both_borrows/load_invalid_shr.stack.stderr b/src/tools/miri/tests/fail/both_borrows/load_invalid_shr.stack.stderr
index ffc73ee43de..e7915d93a26 100644
--- a/src/tools/miri/tests/fail/both_borrows/load_invalid_shr.stack.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/load_invalid_shr.stack.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: trying to retag from <TAG> for SharedReadOnly permiss
   --> tests/fail/both_borrows/load_invalid_shr.rs:LL:CC
    |
 LL |     let _val = *xref_in_mem;
-   |                ^^^^^^^^^^^^
-   |                |
-   |                trying to retag from <TAG> for SharedReadOnly permission at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
-   |                this error occurs as part of retag at ALLOC[0x0..0x4]
+   |                ^^^^^^^^^^^^ this error occurs as part of retag at ALLOC[0x0..0x4]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/both_borrows/load_invalid_shr.tree.stderr b/src/tools/miri/tests/fail/both_borrows/load_invalid_shr.tree.stderr
index 4610739739c..86c12603c07 100644
--- a/src/tools/miri/tests/fail/both_borrows/load_invalid_shr.tree.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/load_invalid_shr.tree.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: reborrow through <TAG> at ALLOC[0x0] is forbidden
   --> tests/fail/both_borrows/load_invalid_shr.rs:LL:CC
    |
 LL |     let _val = *xref_in_mem;
-   |                ^^^^^^^^^^^^ reborrow through <TAG> at ALLOC[0x0] is forbidden
+   |                ^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> has state Disabled which forbids this reborrow (acting as a child read access)
diff --git a/src/tools/miri/tests/fail/both_borrows/mut_exclusive_violation1.stack.stderr b/src/tools/miri/tests/fail/both_borrows/mut_exclusive_violation1.stack.stderr
index 92df9bcbe38..3c8316ca5bc 100644
--- a/src/tools/miri/tests/fail/both_borrows/mut_exclusive_violation1.stack.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/mut_exclusive_violation1.stack.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: attempting a write access using <TAG> at ALLOC[0x0],
   --> tests/fail/both_borrows/mut_exclusive_violation1.rs:LL:CC
    |
 LL |         *LEAK = 7;
-   |         ^^^^^^^^^
-   |         |
-   |         attempting a write access using <TAG> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
-   |         this error occurs as part of an access at ALLOC[0x0..0x4]
+   |         ^^^^^^^^^ this error occurs as part of an access at ALLOC[0x0..0x4]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/both_borrows/mut_exclusive_violation1.tree.stderr b/src/tools/miri/tests/fail/both_borrows/mut_exclusive_violation1.tree.stderr
index 46660d31295..5f14f23e8d6 100644
--- a/src/tools/miri/tests/fail/both_borrows/mut_exclusive_violation1.tree.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/mut_exclusive_violation1.tree.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: write access through <TAG> at ALLOC[0x0] is forbidden
   --> tests/fail/both_borrows/mut_exclusive_violation1.rs:LL:CC
    |
 LL |         *LEAK = 7;
-   |         ^^^^^^^^^ write access through <TAG> at ALLOC[0x0] is forbidden
+   |         ^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> has state Disabled which forbids this child write access
diff --git a/src/tools/miri/tests/fail/both_borrows/mut_exclusive_violation2.stack.stderr b/src/tools/miri/tests/fail/both_borrows/mut_exclusive_violation2.stack.stderr
index 42e30cf10c9..21690d6c4c2 100644
--- a/src/tools/miri/tests/fail/both_borrows/mut_exclusive_violation2.stack.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/mut_exclusive_violation2.stack.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: attempting a read access using <TAG> at ALLOC[0x0], b
   --> tests/fail/both_borrows/mut_exclusive_violation2.rs:LL:CC
    |
 LL |         let _val = *raw1;
-   |                    ^^^^^
-   |                    |
-   |                    attempting a read access using <TAG> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
-   |                    this error occurs as part of an access at ALLOC[0x0..0x4]
+   |                    ^^^^^ this error occurs as part of an access at ALLOC[0x0..0x4]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/both_borrows/mut_exclusive_violation2.tree.stderr b/src/tools/miri/tests/fail/both_borrows/mut_exclusive_violation2.tree.stderr
index a9b1b49e385..edc72b0abbf 100644
--- a/src/tools/miri/tests/fail/both_borrows/mut_exclusive_violation2.tree.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/mut_exclusive_violation2.tree.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: write access through <TAG> at ALLOC[0x0] is forbidden
   --> tests/fail/both_borrows/mut_exclusive_violation2.rs:LL:CC
    |
 LL |         *raw1 = 3;
-   |         ^^^^^^^^^ write access through <TAG> at ALLOC[0x0] is forbidden
+   |         ^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> has state Disabled which forbids this child write access
diff --git a/src/tools/miri/tests/fail/both_borrows/newtype_pair_retagging.stack.stderr b/src/tools/miri/tests/fail/both_borrows/newtype_pair_retagging.stack.stderr
index f428447230a..7cee5fb1369 100644
--- a/src/tools/miri/tests/fail/both_borrows/newtype_pair_retagging.stack.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/newtype_pair_retagging.stack.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: not granting access to tag <TAG> because that would r
   --> RUSTLIB/alloc/src/boxed.rs:LL:CC
    |
 LL |         Box(unsafe { Unique::new_unchecked(raw) }, alloc)
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ not granting access to tag <TAG> because that would remove [Unique for <TAG>] which is strongly protected
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/both_borrows/newtype_pair_retagging.tree.stderr b/src/tools/miri/tests/fail/both_borrows/newtype_pair_retagging.tree.stderr
index ef1aa74ddf4..1984a6a0746 100644
--- a/src/tools/miri/tests/fail/both_borrows/newtype_pair_retagging.tree.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/newtype_pair_retagging.tree.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: deallocation through <TAG> at ALLOC[0x0] is forbidden
   --> RUSTLIB/alloc/src/boxed.rs:LL:CC
    |
 LL |                 self.1.deallocate(From::from(ptr.cast()), layout);
-   |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ deallocation through <TAG> at ALLOC[0x0] is forbidden
+   |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> is foreign to the protected tag <TAG> (i.e., it is not a child)
diff --git a/src/tools/miri/tests/fail/both_borrows/newtype_retagging.stack.stderr b/src/tools/miri/tests/fail/both_borrows/newtype_retagging.stack.stderr
index 0410c2488db..7bd42fc20ce 100644
--- a/src/tools/miri/tests/fail/both_borrows/newtype_retagging.stack.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/newtype_retagging.stack.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: not granting access to tag <TAG> because that would r
   --> RUSTLIB/alloc/src/boxed.rs:LL:CC
    |
 LL |         Box(unsafe { Unique::new_unchecked(raw) }, alloc)
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ not granting access to tag <TAG> because that would remove [Unique for <TAG>] which is strongly protected
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/both_borrows/newtype_retagging.tree.stderr b/src/tools/miri/tests/fail/both_borrows/newtype_retagging.tree.stderr
index 28fcd1411f9..7bd0cd14d79 100644
--- a/src/tools/miri/tests/fail/both_borrows/newtype_retagging.tree.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/newtype_retagging.tree.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: deallocation through <TAG> at ALLOC[0x0] is forbidden
   --> RUSTLIB/alloc/src/boxed.rs:LL:CC
    |
 LL |                 self.1.deallocate(From::from(ptr.cast()), layout);
-   |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ deallocation through <TAG> at ALLOC[0x0] is forbidden
+   |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> is foreign to the protected tag <TAG> (i.e., it is not a child)
diff --git a/src/tools/miri/tests/fail/both_borrows/outdated_local.stack.stderr b/src/tools/miri/tests/fail/both_borrows/outdated_local.stack.stderr
index 79d3538e920..8c1de1a38f0 100644
--- a/src/tools/miri/tests/fail/both_borrows/outdated_local.stack.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/outdated_local.stack.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: attempting a read access using <TAG> at ALLOC[0x0], b
   --> tests/fail/both_borrows/outdated_local.rs:LL:CC
    |
 LL |     assert_eq!(unsafe { *y }, 1);
-   |                         ^^
-   |                         |
-   |                         attempting a read access using <TAG> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
-   |                         this error occurs as part of an access at ALLOC[0x0..0x4]
+   |                         ^^ this error occurs as part of an access at ALLOC[0x0..0x4]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/both_borrows/outdated_local.tree.stderr b/src/tools/miri/tests/fail/both_borrows/outdated_local.tree.stderr
index fffa83a9628..8cb44d2635f 100644
--- a/src/tools/miri/tests/fail/both_borrows/outdated_local.tree.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/outdated_local.tree.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: read access through <TAG> at ALLOC[0x0] is forbidden
   --> tests/fail/both_borrows/outdated_local.rs:LL:CC
    |
 LL |     assert_eq!(unsafe { *y }, 1);
-   |                         ^^ read access through <TAG> at ALLOC[0x0] is forbidden
+   |                         ^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> has state Disabled which forbids this child read access
diff --git a/src/tools/miri/tests/fail/both_borrows/pass_invalid_shr.stack.stderr b/src/tools/miri/tests/fail/both_borrows/pass_invalid_shr.stack.stderr
index 108c78abef5..712764d25ee 100644
--- a/src/tools/miri/tests/fail/both_borrows/pass_invalid_shr.stack.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/pass_invalid_shr.stack.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: trying to retag from <TAG> for SharedReadOnly permiss
   --> tests/fail/both_borrows/pass_invalid_shr.rs:LL:CC
    |
 LL |     foo(xref);
-   |         ^^^^
-   |         |
-   |         trying to retag from <TAG> for SharedReadOnly permission at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
-   |         this error occurs as part of retag at ALLOC[0x0..0x4]
+   |         ^^^^ this error occurs as part of retag at ALLOC[0x0..0x4]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/both_borrows/pass_invalid_shr.tree.stderr b/src/tools/miri/tests/fail/both_borrows/pass_invalid_shr.tree.stderr
index 59750d56470..1bd760426da 100644
--- a/src/tools/miri/tests/fail/both_borrows/pass_invalid_shr.tree.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/pass_invalid_shr.tree.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: reborrow through <TAG> at ALLOC[0x0] is forbidden
   --> tests/fail/both_borrows/pass_invalid_shr.rs:LL:CC
    |
 LL |     foo(xref);
-   |         ^^^^ reborrow through <TAG> at ALLOC[0x0] is forbidden
+   |         ^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> has state Disabled which forbids this reborrow (acting as a child read access)
diff --git a/src/tools/miri/tests/fail/both_borrows/pass_invalid_shr_option.stack.stderr b/src/tools/miri/tests/fail/both_borrows/pass_invalid_shr_option.stack.stderr
index 5aca026cb76..5845f6d5077 100644
--- a/src/tools/miri/tests/fail/both_borrows/pass_invalid_shr_option.stack.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/pass_invalid_shr_option.stack.stderr
@@ -4,7 +4,6 @@ error: Undefined Behavior: trying to retag from <TAG> for SharedReadOnly permiss
 LL |     foo(some_xref);
    |         ^^^^^^^^^
    |         |
-   |         trying to retag from <TAG> for SharedReadOnly permission at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
    |         this error occurs as part of retag (of a reference/box inside this compound value) at ALLOC[0x0..0x4]
    |         errors for retagging in fields are fairly new; please reach out to us (e.g. at <https://rust-lang.zulipchat.com/#narrow/stream/269128-miri>) if you find this error troubling
    |
diff --git a/src/tools/miri/tests/fail/both_borrows/pass_invalid_shr_option.tree.stderr b/src/tools/miri/tests/fail/both_borrows/pass_invalid_shr_option.tree.stderr
index de63c9609a6..2f999a8aae0 100644
--- a/src/tools/miri/tests/fail/both_borrows/pass_invalid_shr_option.tree.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/pass_invalid_shr_option.tree.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: reborrow through <TAG> at ALLOC[0x0] is forbidden
   --> tests/fail/both_borrows/pass_invalid_shr_option.rs:LL:CC
    |
 LL |     foo(some_xref);
-   |         ^^^^^^^^^ reborrow through <TAG> at ALLOC[0x0] is forbidden
+   |         ^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> has state Disabled which forbids this reborrow (acting as a child read access)
diff --git a/src/tools/miri/tests/fail/both_borrows/pass_invalid_shr_tuple.stack.stderr b/src/tools/miri/tests/fail/both_borrows/pass_invalid_shr_tuple.stack.stderr
index 16c2af081ad..41842daa947 100644
--- a/src/tools/miri/tests/fail/both_borrows/pass_invalid_shr_tuple.stack.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/pass_invalid_shr_tuple.stack.stderr
@@ -4,7 +4,6 @@ error: Undefined Behavior: trying to retag from <TAG> for SharedReadOnly permiss
 LL |     foo(pair_xref);
    |         ^^^^^^^^^
    |         |
-   |         trying to retag from <TAG> for SharedReadOnly permission at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
    |         this error occurs as part of retag (of a reference/box inside this compound value) at ALLOC[0x0..0x4]
    |         errors for retagging in fields are fairly new; please reach out to us (e.g. at <https://rust-lang.zulipchat.com/#narrow/stream/269128-miri>) if you find this error troubling
    |
diff --git a/src/tools/miri/tests/fail/both_borrows/pass_invalid_shr_tuple.tree.stderr b/src/tools/miri/tests/fail/both_borrows/pass_invalid_shr_tuple.tree.stderr
index d2a727a920d..b30bda598d2 100644
--- a/src/tools/miri/tests/fail/both_borrows/pass_invalid_shr_tuple.tree.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/pass_invalid_shr_tuple.tree.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: reborrow through <TAG> at ALLOC[0x0] is forbidden
   --> tests/fail/both_borrows/pass_invalid_shr_tuple.rs:LL:CC
    |
 LL |     foo(pair_xref);
-   |         ^^^^^^^^^ reborrow through <TAG> at ALLOC[0x0] is forbidden
+   |         ^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> has state Disabled which forbids this reborrow (acting as a child read access)
diff --git a/src/tools/miri/tests/fail/both_borrows/retag_data_race_write.stack.stderr b/src/tools/miri/tests/fail/both_borrows/retag_data_race_write.stack.stderr
index 6bc66f24192..d97850d7a44 100644
--- a/src/tools/miri/tests/fail/both_borrows/retag_data_race_write.stack.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/retag_data_race_write.stack.stderr
@@ -1,8 +1,8 @@
-error: Undefined Behavior: Data race detected between (1) retag write on thread `unnamed-ID` and (2) non-atomic write on thread `unnamed-ID` at ALLOC. (2) just happened here
+error: Undefined Behavior: Data race detected between (1) retag write on thread `unnamed-ID` and (2) non-atomic write on thread `unnamed-ID` at ALLOC
   --> tests/fail/both_borrows/retag_data_race_write.rs:LL:CC
    |
-LL |         *p = 5;
-   |         ^^^^^^ Data race detected between (1) retag write on thread `unnamed-ID` and (2) non-atomic write on thread `unnamed-ID` at ALLOC. (2) just happened here
+LL | ...   *p = 5;
+   |       ^^^^^^ (2) just happened here
    |
 help: and (1) occurred earlier here
   --> tests/fail/both_borrows/retag_data_race_write.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/both_borrows/retag_data_race_write.tree.stderr b/src/tools/miri/tests/fail/both_borrows/retag_data_race_write.tree.stderr
index 510e592539f..c1b37f8a9bf 100644
--- a/src/tools/miri/tests/fail/both_borrows/retag_data_race_write.tree.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/retag_data_race_write.tree.stderr
@@ -1,8 +1,8 @@
-error: Undefined Behavior: Data race detected between (1) retag read on thread `unnamed-ID` and (2) non-atomic write on thread `unnamed-ID` at ALLOC. (2) just happened here
+error: Undefined Behavior: Data race detected between (1) retag read on thread `unnamed-ID` and (2) non-atomic write on thread `unnamed-ID` at ALLOC
   --> tests/fail/both_borrows/retag_data_race_write.rs:LL:CC
    |
-LL |         *p = 5;
-   |         ^^^^^^ Data race detected between (1) retag read on thread `unnamed-ID` and (2) non-atomic write on thread `unnamed-ID` at ALLOC. (2) just happened here
+LL | ...   *p = 5;
+   |       ^^^^^^ (2) just happened here
    |
 help: and (1) occurred earlier here
   --> tests/fail/both_borrows/retag_data_race_write.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/both_borrows/return_invalid_shr.stack.stderr b/src/tools/miri/tests/fail/both_borrows/return_invalid_shr.stack.stderr
index 0ac3ed9db35..d52143500c4 100644
--- a/src/tools/miri/tests/fail/both_borrows/return_invalid_shr.stack.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/return_invalid_shr.stack.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: trying to retag from <TAG> for SharedReadOnly permiss
   --> tests/fail/both_borrows/return_invalid_shr.rs:LL:CC
    |
 LL |     ret
-   |     ^^^
-   |     |
-   |     trying to retag from <TAG> for SharedReadOnly permission at ALLOC[0x4], but that tag does not exist in the borrow stack for this location
-   |     this error occurs as part of retag at ALLOC[0x4..0x8]
+   |     ^^^ this error occurs as part of retag at ALLOC[0x4..0x8]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/both_borrows/return_invalid_shr.tree.stderr b/src/tools/miri/tests/fail/both_borrows/return_invalid_shr.tree.stderr
index cc51f4c77ee..2b2650a254d 100644
--- a/src/tools/miri/tests/fail/both_borrows/return_invalid_shr.tree.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/return_invalid_shr.tree.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: reborrow through <TAG> at ALLOC[0x4] is forbidden
   --> tests/fail/both_borrows/return_invalid_shr.rs:LL:CC
    |
 LL |     ret
-   |     ^^^ reborrow through <TAG> at ALLOC[0x4] is forbidden
+   |     ^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> has state Disabled which forbids this reborrow (acting as a child read access)
diff --git a/src/tools/miri/tests/fail/both_borrows/return_invalid_shr_option.stack.stderr b/src/tools/miri/tests/fail/both_borrows/return_invalid_shr_option.stack.stderr
index d8e0f52ff02..d66c8eeb1af 100644
--- a/src/tools/miri/tests/fail/both_borrows/return_invalid_shr_option.stack.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/return_invalid_shr_option.stack.stderr
@@ -4,7 +4,6 @@ error: Undefined Behavior: trying to retag from <TAG> for SharedReadOnly permiss
 LL |     ret
    |     ^^^
    |     |
-   |     trying to retag from <TAG> for SharedReadOnly permission at ALLOC[0x4], but that tag does not exist in the borrow stack for this location
    |     this error occurs as part of retag (of a reference/box inside this compound value) at ALLOC[0x4..0x8]
    |     errors for retagging in fields are fairly new; please reach out to us (e.g. at <https://rust-lang.zulipchat.com/#narrow/stream/269128-miri>) if you find this error troubling
    |
diff --git a/src/tools/miri/tests/fail/both_borrows/return_invalid_shr_option.tree.stderr b/src/tools/miri/tests/fail/both_borrows/return_invalid_shr_option.tree.stderr
index 7a7d8f20fa8..b8e963f87d9 100644
--- a/src/tools/miri/tests/fail/both_borrows/return_invalid_shr_option.tree.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/return_invalid_shr_option.tree.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: reborrow through <TAG> at ALLOC[0x4] is forbidden
   --> tests/fail/both_borrows/return_invalid_shr_option.rs:LL:CC
    |
 LL |     ret
-   |     ^^^ reborrow through <TAG> at ALLOC[0x4] is forbidden
+   |     ^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> has state Disabled which forbids this reborrow (acting as a child read access)
diff --git a/src/tools/miri/tests/fail/both_borrows/return_invalid_shr_tuple.stack.stderr b/src/tools/miri/tests/fail/both_borrows/return_invalid_shr_tuple.stack.stderr
index 38b8758964b..727b52ec729 100644
--- a/src/tools/miri/tests/fail/both_borrows/return_invalid_shr_tuple.stack.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/return_invalid_shr_tuple.stack.stderr
@@ -4,7 +4,6 @@ error: Undefined Behavior: trying to retag from <TAG> for SharedReadOnly permiss
 LL |     ret
    |     ^^^
    |     |
-   |     trying to retag from <TAG> for SharedReadOnly permission at ALLOC[0x4], but that tag does not exist in the borrow stack for this location
    |     this error occurs as part of retag (of a reference/box inside this compound value) at ALLOC[0x4..0x8]
    |     errors for retagging in fields are fairly new; please reach out to us (e.g. at <https://rust-lang.zulipchat.com/#narrow/stream/269128-miri>) if you find this error troubling
    |
diff --git a/src/tools/miri/tests/fail/both_borrows/return_invalid_shr_tuple.tree.stderr b/src/tools/miri/tests/fail/both_borrows/return_invalid_shr_tuple.tree.stderr
index 57b4f5fbe2d..8e499369f08 100644
--- a/src/tools/miri/tests/fail/both_borrows/return_invalid_shr_tuple.tree.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/return_invalid_shr_tuple.tree.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: reborrow through <TAG> at ALLOC[0x4] is forbidden
   --> tests/fail/both_borrows/return_invalid_shr_tuple.rs:LL:CC
    |
 LL |     ret
-   |     ^^^ reborrow through <TAG> at ALLOC[0x4] is forbidden
+   |     ^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> has state Disabled which forbids this reborrow (acting as a child read access)
diff --git a/src/tools/miri/tests/fail/both_borrows/shr_frozen_violation1.stack.stderr b/src/tools/miri/tests/fail/both_borrows/shr_frozen_violation1.stack.stderr
index 22efda1efae..eed8c0273ab 100644
--- a/src/tools/miri/tests/fail/both_borrows/shr_frozen_violation1.stack.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/shr_frozen_violation1.stack.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: attempting a write access using <TAG> at ALLOC[0x0],
   --> tests/fail/both_borrows/shr_frozen_violation1.rs:LL:CC
    |
 LL |         *(x as *const i32 as *mut i32) = 7;
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |         |
-   |         attempting a write access using <TAG> at ALLOC[0x0], but that tag only grants SharedReadOnly permission for this location
-   |         this error occurs as part of an access at ALLOC[0x0..0x4]
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ this error occurs as part of an access at ALLOC[0x0..0x4]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/both_borrows/shr_frozen_violation1.tree.stderr b/src/tools/miri/tests/fail/both_borrows/shr_frozen_violation1.tree.stderr
index 2e544583cb2..a28754f5412 100644
--- a/src/tools/miri/tests/fail/both_borrows/shr_frozen_violation1.tree.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/shr_frozen_violation1.tree.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: write access through <TAG> at ALLOC[0x0] is forbidden
   --> tests/fail/both_borrows/shr_frozen_violation1.rs:LL:CC
    |
 LL |         *(x as *const i32 as *mut i32) = 7;
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ write access through <TAG> at ALLOC[0x0] is forbidden
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> has state Frozen which forbids this child write access
diff --git a/src/tools/miri/tests/fail/both_borrows/shr_frozen_violation2.stack.stderr b/src/tools/miri/tests/fail/both_borrows/shr_frozen_violation2.stack.stderr
index 7e6d057a4b6..39a21e60a1b 100644
--- a/src/tools/miri/tests/fail/both_borrows/shr_frozen_violation2.stack.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/shr_frozen_violation2.stack.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: attempting a read access using <TAG> at ALLOC[0x0], b
   --> tests/fail/both_borrows/shr_frozen_violation2.rs:LL:CC
    |
 LL |         let _val = *frozen;
-   |                    ^^^^^^^
-   |                    |
-   |                    attempting a read access using <TAG> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
-   |                    this error occurs as part of an access at ALLOC[0x0..0x4]
+   |                    ^^^^^^^ this error occurs as part of an access at ALLOC[0x0..0x4]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/both_borrows/shr_frozen_violation2.tree.stderr b/src/tools/miri/tests/fail/both_borrows/shr_frozen_violation2.tree.stderr
index 17c4542e195..0eb2dc3df77 100644
--- a/src/tools/miri/tests/fail/both_borrows/shr_frozen_violation2.tree.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/shr_frozen_violation2.tree.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: read access through <TAG> at ALLOC[0x0] is forbidden
   --> tests/fail/both_borrows/shr_frozen_violation2.rs:LL:CC
    |
 LL |         let _val = *frozen;
-   |                    ^^^^^^^ read access through <TAG> at ALLOC[0x0] is forbidden
+   |                    ^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> has state Disabled which forbids this child read access
diff --git a/src/tools/miri/tests/fail/both_borrows/zero-sized-protected.stack.stderr b/src/tools/miri/tests/fail/both_borrows/zero-sized-protected.stack.stderr
index c01fa2a86c2..3e4a7ccac36 100644
--- a/src/tools/miri/tests/fail/both_borrows/zero-sized-protected.stack.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/zero-sized-protected.stack.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: entering unreachable code
   --> tests/fail/both_borrows/zero-sized-protected.rs:LL:CC
    |
 LL |     unsafe { std::hint::unreachable_unchecked() };
-   |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ entering unreachable code
+   |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/both_borrows/zero-sized-protected.tree.stderr b/src/tools/miri/tests/fail/both_borrows/zero-sized-protected.tree.stderr
index 18d1fb69395..2a9a9afb0f0 100644
--- a/src/tools/miri/tests/fail/both_borrows/zero-sized-protected.tree.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/zero-sized-protected.tree.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: deallocation through <TAG> (root of the allocation) a
   --> tests/fail/both_borrows/zero-sized-protected.rs:LL:CC
    |
 LL |     unsafe { dealloc(ptr, l) };
-   |              ^^^^^^^^^^^^^^^ deallocation through <TAG> (root of the allocation) at ALLOC[0x0] is forbidden
+   |              ^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the allocation of the accessed tag <TAG> (root of the allocation) also contains the strongly protected tag <TAG>
diff --git a/src/tools/miri/tests/fail/box-cell-alias.stderr b/src/tools/miri/tests/fail/box-cell-alias.stderr
index f9cc6003dc6..8e1e9370c70 100644
--- a/src/tools/miri/tests/fail/box-cell-alias.stderr
+++ b/src/tools/miri/tests/fail/box-cell-alias.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: trying to retag from <TAG> for SharedReadWrite permis
   --> tests/fail/box-cell-alias.rs:LL:CC
    |
 LL |     unsafe { (*ptr).set(20) };
-   |              ^^^^^^
-   |              |
-   |              trying to retag from <TAG> for SharedReadWrite permission at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
-   |              this error occurs as part of retag at ALLOC[0x0..0x1]
+   |              ^^^^^^ this error occurs as part of retag at ALLOC[0x0..0x1]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/branchless-select-i128-pointer.stderr b/src/tools/miri/tests/fail/branchless-select-i128-pointer.stderr
index d9de23dc912..3f44ef789e9 100644
--- a/src/tools/miri/tests/fail/branchless-select-i128-pointer.stderr
+++ b/src/tools/miri/tests/fail/branchless-select-i128-pointer.stderr
@@ -6,7 +6,7 @@ LL | |
 LL | |                 !mask & transmute::<_, TwoPtrs>("false !")
 LL | |                     | mask & transmute::<_, TwoPtrs>("true !"),
 LL | |             )
-   | |_____________^ constructing invalid value: encountered a dangling reference ($HEX[noalloc] has no provenance)
+   | |_____________^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/breakpoint.stderr b/src/tools/miri/tests/fail/breakpoint.stderr
index f203cb0c15f..1963e9c9ec1 100644
--- a/src/tools/miri/tests/fail/breakpoint.stderr
+++ b/src/tools/miri/tests/fail/breakpoint.stderr
@@ -2,7 +2,7 @@ error: abnormal termination: trace/breakpoint trap
   --> tests/fail/breakpoint.rs:LL:CC
    |
 LL |     core::intrinsics::breakpoint();
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ trace/breakpoint trap
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ abnormal termination occurred here
    |
    = note: BACKTRACE:
    = note: inside `main` at tests/fail/breakpoint.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/concurrency/mutex-leak-move-deadlock.stderr b/src/tools/miri/tests/fail/concurrency/mutex-leak-move-deadlock.stderr
index 0ca8b3558d4..cc487c62d08 100644
--- a/src/tools/miri/tests/fail/concurrency/mutex-leak-move-deadlock.stderr
+++ b/src/tools/miri/tests/fail/concurrency/mutex-leak-move-deadlock.stderr
@@ -1,8 +1,8 @@
-error: deadlock: the evaluated program deadlocked
+error: the evaluated program deadlocked
   --> RUSTLIB/std/$FILE:LL:CC
    |
 LL | $CODE
-   | ^ the evaluated program deadlocked
+   | ^ this thread got stuck here
    |
 note: inside `main`
   --> tests/fail/concurrency/mutex-leak-move-deadlock.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/concurrency/read_only_atomic_cmpxchg.stderr b/src/tools/miri/tests/fail/concurrency/read_only_atomic_cmpxchg.stderr
index 62ade0a6793..9010033ca70 100644
--- a/src/tools/miri/tests/fail/concurrency/read_only_atomic_cmpxchg.stderr
+++ b/src/tools/miri/tests/fail/concurrency/read_only_atomic_cmpxchg.stderr
@@ -3,8 +3,7 @@ error: Undefined Behavior: atomic store and read-modify-write operations cannot
   --> tests/fail/concurrency/read_only_atomic_cmpxchg.rs:LL:CC
    |
 LL |     x.compare_exchange(1, 2, Ordering::Relaxed, Ordering::Relaxed).unwrap_err();
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ atomic store and read-modify-write operations cannot be performed on read-only memory
-see <https://doc.rust-lang.org/nightly/std/sync/atomic/index.html#atomic-accesses-to-read-only-memory> for more information
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/concurrency/read_only_atomic_load_acquire.stderr b/src/tools/miri/tests/fail/concurrency/read_only_atomic_load_acquire.stderr
index 6a3776feba6..b9e492f89be 100644
--- a/src/tools/miri/tests/fail/concurrency/read_only_atomic_load_acquire.stderr
+++ b/src/tools/miri/tests/fail/concurrency/read_only_atomic_load_acquire.stderr
@@ -4,9 +4,7 @@ error: Undefined Behavior: non-relaxed atomic load operations cannot be performe
   --> tests/fail/concurrency/read_only_atomic_load_acquire.rs:LL:CC
    |
 LL |     x.load(Ordering::Acquire);
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^ non-relaxed atomic load operations cannot be performed on read-only memory
-these operations sometimes have to be implemented using read-modify-write operations, which require writeable memory
-see <https://doc.rust-lang.org/nightly/std/sync/atomic/index.html#atomic-accesses-to-read-only-memory> for more information
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/concurrency/read_only_atomic_load_large.stderr b/src/tools/miri/tests/fail/concurrency/read_only_atomic_load_large.stderr
index f4cec9879b7..1fcc88f8735 100644
--- a/src/tools/miri/tests/fail/concurrency/read_only_atomic_load_large.stderr
+++ b/src/tools/miri/tests/fail/concurrency/read_only_atomic_load_large.stderr
@@ -4,9 +4,7 @@ error: Undefined Behavior: large atomic load operations cannot be performed on r
   --> tests/fail/concurrency/read_only_atomic_load_large.rs:LL:CC
    |
 LL |     x.load(Ordering::Relaxed);
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^ large atomic load operations cannot be performed on read-only memory
-these operations often have to be implemented using read-modify-write operations, which require writeable memory
-see <https://doc.rust-lang.org/nightly/std/sync/atomic/index.html#atomic-accesses-to-read-only-memory> for more information
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/coroutine-pinned-moved.stderr b/src/tools/miri/tests/fail/coroutine-pinned-moved.stderr
index 9b4890c7cc6..70ecfa9379a 100644
--- a/src/tools/miri/tests/fail/coroutine-pinned-moved.stderr
+++ b/src/tools/miri/tests/fail/coroutine-pinned-moved.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: memory access failed: ALLOC has been freed, so this p
   --> tests/fail/coroutine-pinned-moved.rs:LL:CC
    |
 LL |         *num += 1;
-   |         ^^^^^^^^^ memory access failed: ALLOC has been freed, so this pointer is dangling
+   |         ^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/dangling_pointers/dangling_pointer_deref.stderr b/src/tools/miri/tests/fail/dangling_pointers/dangling_pointer_deref.stderr
index 7613552b4b0..7ddb5be5425 100644
--- a/src/tools/miri/tests/fail/dangling_pointers/dangling_pointer_deref.stderr
+++ b/src/tools/miri/tests/fail/dangling_pointers/dangling_pointer_deref.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: memory access failed: ALLOC has been freed, so this p
   --> tests/fail/dangling_pointers/dangling_pointer_deref.rs:LL:CC
    |
 LL |     let x = unsafe { *p };
-   |                      ^^ memory access failed: ALLOC has been freed, so this pointer is dangling
+   |                      ^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/dangling_pointers/dangling_pointer_deref_match_never.stderr b/src/tools/miri/tests/fail/dangling_pointers/dangling_pointer_deref_match_never.stderr
index 032cbccaf9b..735e90328d7 100644
--- a/src/tools/miri/tests/fail/dangling_pointers/dangling_pointer_deref_match_never.stderr
+++ b/src/tools/miri/tests/fail/dangling_pointers/dangling_pointer_deref_match_never.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: entering unreachable code
   --> tests/fail/dangling_pointers/dangling_pointer_deref_match_never.rs:LL:CC
    |
 LL |         match *p {}
-   |               ^^ entering unreachable code
+   |               ^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/dangling_pointers/dangling_pointer_offset.stderr b/src/tools/miri/tests/fail/dangling_pointers/dangling_pointer_offset.stderr
index fd1a5e7faaf..2b34001ddf3 100644
--- a/src/tools/miri/tests/fail/dangling_pointers/dangling_pointer_offset.stderr
+++ b/src/tools/miri/tests/fail/dangling_pointers/dangling_pointer_offset.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: in-bounds pointer arithmetic failed: ALLOC has been f
   --> tests/fail/dangling_pointers/dangling_pointer_offset.rs:LL:CC
    |
 LL |     let x = unsafe { p.offset(42) };
-   |                      ^^^^^^^^^^^^ in-bounds pointer arithmetic failed: ALLOC has been freed, so this pointer is dangling
+   |                      ^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/dangling_pointers/dangling_pointer_project_underscore_let.stderr b/src/tools/miri/tests/fail/dangling_pointers/dangling_pointer_project_underscore_let.stderr
index ffb8bc9507b..04ac535448b 100644
--- a/src/tools/miri/tests/fail/dangling_pointers/dangling_pointer_project_underscore_let.stderr
+++ b/src/tools/miri/tests/fail/dangling_pointers/dangling_pointer_project_underscore_let.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: in-bounds pointer arithmetic failed: ALLOC has been f
   --> tests/fail/dangling_pointers/dangling_pointer_project_underscore_let.rs:LL:CC
    |
 LL |         let _ = (*p).1;
-   |                 ^^^^^^ in-bounds pointer arithmetic failed: ALLOC has been freed, so this pointer is dangling
+   |                 ^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/dangling_pointers/dangling_pointer_project_underscore_let_type_annotation.stderr b/src/tools/miri/tests/fail/dangling_pointers/dangling_pointer_project_underscore_let_type_annotation.stderr
index cf3e1db13d3..cd44f728bf6 100644
--- a/src/tools/miri/tests/fail/dangling_pointers/dangling_pointer_project_underscore_let_type_annotation.stderr
+++ b/src/tools/miri/tests/fail/dangling_pointers/dangling_pointer_project_underscore_let_type_annotation.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: in-bounds pointer arithmetic failed: ALLOC has been f
   --> tests/fail/dangling_pointers/dangling_pointer_project_underscore_let_type_annotation.rs:LL:CC
    |
 LL |         let _: u8 = (*p).1;
-   |                     ^^^^^^ in-bounds pointer arithmetic failed: ALLOC has been freed, so this pointer is dangling
+   |                     ^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/dangling_pointers/dangling_pointer_project_underscore_match.stderr b/src/tools/miri/tests/fail/dangling_pointers/dangling_pointer_project_underscore_match.stderr
index e2d04433b63..c49e663fd42 100644
--- a/src/tools/miri/tests/fail/dangling_pointers/dangling_pointer_project_underscore_match.stderr
+++ b/src/tools/miri/tests/fail/dangling_pointers/dangling_pointer_project_underscore_match.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: in-bounds pointer arithmetic failed: ALLOC has been f
   --> tests/fail/dangling_pointers/dangling_pointer_project_underscore_match.rs:LL:CC
    |
 LL |         match (*p).1 {
-   |               ^^^^^^ in-bounds pointer arithmetic failed: ALLOC has been freed, so this pointer is dangling
+   |               ^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/dangling_pointers/dangling_pointer_to_raw_pointer.stderr b/src/tools/miri/tests/fail/dangling_pointers/dangling_pointer_to_raw_pointer.stderr
index 5a2b85696ab..df2b227c809 100644
--- a/src/tools/miri/tests/fail/dangling_pointers/dangling_pointer_to_raw_pointer.stderr
+++ b/src/tools/miri/tests/fail/dangling_pointers/dangling_pointer_to_raw_pointer.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: pointer not dereferenceable: pointer must be derefere
   --> tests/fail/dangling_pointers/dangling_pointer_to_raw_pointer.rs:LL:CC
    |
 LL |     unsafe { &(*x).0 as *const i32 }
-   |              ^^^^^^^ pointer not dereferenceable: pointer must be dereferenceable for 4 bytes, but got 0x10[noalloc] which is a dangling pointer (it has no provenance)
+   |              ^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/dangling_pointers/dangling_primitive.stderr b/src/tools/miri/tests/fail/dangling_pointers/dangling_primitive.stderr
index 2d7456c15b9..d89f79ec1d5 100644
--- a/src/tools/miri/tests/fail/dangling_pointers/dangling_primitive.stderr
+++ b/src/tools/miri/tests/fail/dangling_pointers/dangling_primitive.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: memory access failed: ALLOC has been freed, so this p
   --> tests/fail/dangling_pointers/dangling_primitive.rs:LL:CC
    |
 LL |         dbg!(*ptr);
-   |         ^^^^^^^^^^ memory access failed: ALLOC has been freed, so this pointer is dangling
+   |         ^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/dangling_pointers/deref-invalid-ptr.stderr b/src/tools/miri/tests/fail/dangling_pointers/deref-invalid-ptr.stderr
index ad4280c2d74..228c259d675 100644
--- a/src/tools/miri/tests/fail/dangling_pointers/deref-invalid-ptr.stderr
+++ b/src/tools/miri/tests/fail/dangling_pointers/deref-invalid-ptr.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: pointer not dereferenceable: pointer must be derefere
   --> tests/fail/dangling_pointers/deref-invalid-ptr.rs:LL:CC
    |
 LL |     let _y = unsafe { &*x as *const u32 };
-   |                       ^^^ pointer not dereferenceable: pointer must be dereferenceable for 4 bytes, but got 0x10[noalloc] which is a dangling pointer (it has no provenance)
+   |                       ^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/dangling_pointers/deref_dangling_box.stderr b/src/tools/miri/tests/fail/dangling_pointers/deref_dangling_box.stderr
index 82802f02b99..8c84975a703 100644
--- a/src/tools/miri/tests/fail/dangling_pointers/deref_dangling_box.stderr
+++ b/src/tools/miri/tests/fail/dangling_pointers/deref_dangling_box.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value: encountered a dangling bo
   --> tests/fail/dangling_pointers/deref_dangling_box.rs:LL:CC
    |
 LL |     let _val = unsafe { addr_of_mut!(**outer) };
-   |                         ^^^^^^^^^^^^^^^^^^^^^ constructing invalid value: encountered a dangling box (0x18[noalloc] has no provenance)
+   |                         ^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/dangling_pointers/deref_dangling_ref.stderr b/src/tools/miri/tests/fail/dangling_pointers/deref_dangling_ref.stderr
index 364d193b0c5..8458a35ef21 100644
--- a/src/tools/miri/tests/fail/dangling_pointers/deref_dangling_ref.stderr
+++ b/src/tools/miri/tests/fail/dangling_pointers/deref_dangling_ref.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value: encountered a dangling re
   --> tests/fail/dangling_pointers/deref_dangling_ref.rs:LL:CC
    |
 LL |     let _val = unsafe { addr_of_mut!(**outer) };
-   |                         ^^^^^^^^^^^^^^^^^^^^^ constructing invalid value: encountered a dangling reference (0x18[noalloc] has no provenance)
+   |                         ^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/dangling_pointers/dyn_size.stderr b/src/tools/miri/tests/fail/dangling_pointers/dyn_size.stderr
index f3596347f61..5ea0d022c3d 100644
--- a/src/tools/miri/tests/fail/dangling_pointers/dyn_size.stderr
+++ b/src/tools/miri/tests/fail/dangling_pointers/dyn_size.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value: encountered a dangling re
   --> tests/fail/dangling_pointers/dyn_size.rs:LL:CC
    |
 LL |     let _ptr = unsafe { &*ptr };
-   |                         ^^^^^ constructing invalid value: encountered a dangling reference (going beyond the bounds of its allocation)
+   |                         ^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/dangling_pointers/null_pointer_deref.stderr b/src/tools/miri/tests/fail/dangling_pointers/null_pointer_deref.stderr
index 3135db9dc6d..d46d2c33122 100644
--- a/src/tools/miri/tests/fail/dangling_pointers/null_pointer_deref.stderr
+++ b/src/tools/miri/tests/fail/dangling_pointers/null_pointer_deref.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: memory access failed: attempting to access 4 bytes, b
   --> tests/fail/dangling_pointers/null_pointer_deref.rs:LL:CC
    |
 LL |     let x: i32 = unsafe { *std::ptr::null() };
-   |                           ^^^^^^^^^^^^^^^^^ memory access failed: attempting to access 4 bytes, but got null pointer
+   |                           ^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/dangling_pointers/null_pointer_write.stderr b/src/tools/miri/tests/fail/dangling_pointers/null_pointer_write.stderr
index 012b38ee5a6..bb12031a3f2 100644
--- a/src/tools/miri/tests/fail/dangling_pointers/null_pointer_write.stderr
+++ b/src/tools/miri/tests/fail/dangling_pointers/null_pointer_write.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: memory access failed: attempting to access 4 bytes, b
   --> tests/fail/dangling_pointers/null_pointer_write.rs:LL:CC
    |
 LL |     unsafe { *std::ptr::null_mut() = 0i32 };
-   |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ memory access failed: attempting to access 4 bytes, but got null pointer
+   |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/dangling_pointers/out_of_bounds_project.stderr b/src/tools/miri/tests/fail/dangling_pointers/out_of_bounds_project.stderr
index c11ccdb45a7..bd531c94dd0 100644
--- a/src/tools/miri/tests/fail/dangling_pointers/out_of_bounds_project.stderr
+++ b/src/tools/miri/tests/fail/dangling_pointers/out_of_bounds_project.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: in-bounds pointer arithmetic failed: attempting to of
   --> tests/fail/dangling_pointers/out_of_bounds_project.rs:LL:CC
    |
 LL |         let _field = addr_of!((*ptr).2);
-   |                      ^^^^^^^^^^^^^^^^^^ in-bounds pointer arithmetic failed: attempting to offset pointer by 8 bytes, but got ALLOC which is only 4 bytes from the end of the allocation
+   |                      ^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/dangling_pointers/out_of_bounds_read.stderr b/src/tools/miri/tests/fail/dangling_pointers/out_of_bounds_read.stderr
index 1de4b806da2..df83190c29f 100644
--- a/src/tools/miri/tests/fail/dangling_pointers/out_of_bounds_read.stderr
+++ b/src/tools/miri/tests/fail/dangling_pointers/out_of_bounds_read.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: memory access failed: attempting to access 2 bytes, b
   --> tests/fail/dangling_pointers/out_of_bounds_read.rs:LL:CC
    |
 LL |     let x = unsafe { *v.as_ptr().wrapping_byte_add(5) };
-   |                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ memory access failed: attempting to access 2 bytes, but got ALLOC+0x5 which is at or beyond the end of the allocation of size 4 bytes
+   |                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/dangling_pointers/out_of_bounds_write.stderr b/src/tools/miri/tests/fail/dangling_pointers/out_of_bounds_write.stderr
index db16d70704e..5c0485a848d 100644
--- a/src/tools/miri/tests/fail/dangling_pointers/out_of_bounds_write.stderr
+++ b/src/tools/miri/tests/fail/dangling_pointers/out_of_bounds_write.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: memory access failed: attempting to access 2 bytes, b
   --> tests/fail/dangling_pointers/out_of_bounds_write.rs:LL:CC
    |
 LL |     unsafe { *v.as_mut_ptr().wrapping_byte_add(5) = 0 };
-   |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ memory access failed: attempting to access 2 bytes, but got ALLOC+0x5 which is at or beyond the end of the allocation of size 4 bytes
+   |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/dangling_pointers/stack_temporary.stderr b/src/tools/miri/tests/fail/dangling_pointers/stack_temporary.stderr
index c617dfdb3a6..79cb8e9f8fa 100644
--- a/src/tools/miri/tests/fail/dangling_pointers/stack_temporary.stderr
+++ b/src/tools/miri/tests/fail/dangling_pointers/stack_temporary.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: memory access failed: ALLOC has been freed, so this p
   --> tests/fail/dangling_pointers/stack_temporary.rs:LL:CC
    |
 LL |         let val = *x;
-   |                   ^^ memory access failed: ALLOC has been freed, so this pointer is dangling
+   |                   ^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/dangling_pointers/storage_dead_dangling.stderr b/src/tools/miri/tests/fail/dangling_pointers/storage_dead_dangling.stderr
index e97427ab7eb..3a3133049b2 100644
--- a/src/tools/miri/tests/fail/dangling_pointers/storage_dead_dangling.stderr
+++ b/src/tools/miri/tests/fail/dangling_pointers/storage_dead_dangling.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: pointer not dereferenceable: pointer must be derefere
   --> tests/fail/dangling_pointers/storage_dead_dangling.rs:LL:CC
    |
 LL |     let _ref = unsafe { &mut *(LEAK as *mut i32) };
-   |                         ^^^^^^^^^^^^^^^^^^^^^^^^ pointer not dereferenceable: pointer must be dereferenceable for 4 bytes, but got $HEX[noalloc] which is a dangling pointer (it has no provenance)
+   |                         ^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/dangling_pointers/wild_pointer_deref.stderr b/src/tools/miri/tests/fail/dangling_pointers/wild_pointer_deref.stderr
index 79e27fa3461..8a8dd9b8f42 100644
--- a/src/tools/miri/tests/fail/dangling_pointers/wild_pointer_deref.stderr
+++ b/src/tools/miri/tests/fail/dangling_pointers/wild_pointer_deref.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: memory access failed: attempting to access 4 bytes, b
   --> tests/fail/dangling_pointers/wild_pointer_deref.rs:LL:CC
    |
 LL |     let x = unsafe { *p };
-   |                      ^^ memory access failed: attempting to access 4 bytes, but got 0x2c[noalloc] which is a dangling pointer (it has no provenance)
+   |                      ^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/data_race/alloc_read_race.stderr b/src/tools/miri/tests/fail/data_race/alloc_read_race.stderr
index e6ee9ce81fd..5e4a09dd0d0 100644
--- a/src/tools/miri/tests/fail/data_race/alloc_read_race.stderr
+++ b/src/tools/miri/tests/fail/data_race/alloc_read_race.stderr
@@ -1,8 +1,8 @@
-error: Undefined Behavior: Data race detected between (1) creating a new allocation on thread `unnamed-ID` and (2) non-atomic read on thread `unnamed-ID` at ALLOC. (2) just happened here
+error: Undefined Behavior: Data race detected between (1) creating a new allocation on thread `unnamed-ID` and (2) non-atomic read on thread `unnamed-ID` at ALLOC
   --> tests/fail/data_race/alloc_read_race.rs:LL:CC
    |
-LL |             *pointer.load(Ordering::Relaxed)
-   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Data race detected between (1) creating a new allocation on thread `unnamed-ID` and (2) non-atomic read on thread `unnamed-ID` at ALLOC. (2) just happened here
+LL | ...   *pointer.load(Ordering::Relaxed)
+   |       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ (2) just happened here
    |
 help: and (1) occurred earlier here
   --> tests/fail/data_race/alloc_read_race.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/data_race/alloc_write_race.stderr b/src/tools/miri/tests/fail/data_race/alloc_write_race.stderr
index 97b54609ade..69bfc33f377 100644
--- a/src/tools/miri/tests/fail/data_race/alloc_write_race.stderr
+++ b/src/tools/miri/tests/fail/data_race/alloc_write_race.stderr
@@ -1,8 +1,8 @@
-error: Undefined Behavior: Data race detected between (1) creating a new allocation on thread `unnamed-ID` and (2) non-atomic write on thread `unnamed-ID` at ALLOC. (2) just happened here
+error: Undefined Behavior: Data race detected between (1) creating a new allocation on thread `unnamed-ID` and (2) non-atomic write on thread `unnamed-ID` at ALLOC
   --> tests/fail/data_race/alloc_write_race.rs:LL:CC
    |
-LL |             *pointer.load(Ordering::Relaxed) = 2;
-   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Data race detected between (1) creating a new allocation on thread `unnamed-ID` and (2) non-atomic write on thread `unnamed-ID` at ALLOC. (2) just happened here
+LL | ...   *pointer.load(Ordering::Relaxed) = 2;
+   |       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ (2) just happened here
    |
 help: and (1) occurred earlier here
   --> tests/fail/data_race/alloc_write_race.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/data_race/atomic_read_na_write_race1.stderr b/src/tools/miri/tests/fail/data_race/atomic_read_na_write_race1.stderr
index d3d6ed2e311..0da4914d411 100644
--- a/src/tools/miri/tests/fail/data_race/atomic_read_na_write_race1.stderr
+++ b/src/tools/miri/tests/fail/data_race/atomic_read_na_write_race1.stderr
@@ -1,8 +1,8 @@
-error: Undefined Behavior: Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) atomic load on thread `unnamed-ID` at ALLOC. (2) just happened here
+error: Undefined Behavior: Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) atomic load on thread `unnamed-ID` at ALLOC
   --> tests/fail/data_race/atomic_read_na_write_race1.rs:LL:CC
    |
-LL |             (&*c.0).load(Ordering::SeqCst)
-   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) atomic load on thread `unnamed-ID` at ALLOC. (2) just happened here
+LL | ...   (&*c.0).load(Ordering::SeqCst)
+   |       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ (2) just happened here
    |
 help: and (1) occurred earlier here
   --> tests/fail/data_race/atomic_read_na_write_race1.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/data_race/atomic_read_na_write_race2.stderr b/src/tools/miri/tests/fail/data_race/atomic_read_na_write_race2.stderr
index ea535ddac4f..a30d3f74906 100644
--- a/src/tools/miri/tests/fail/data_race/atomic_read_na_write_race2.stderr
+++ b/src/tools/miri/tests/fail/data_race/atomic_read_na_write_race2.stderr
@@ -1,8 +1,8 @@
-error: Undefined Behavior: Data race detected between (1) atomic load on thread `unnamed-ID` and (2) non-atomic write on thread `unnamed-ID` at ALLOC. (2) just happened here
+error: Undefined Behavior: Data race detected between (1) atomic load on thread `unnamed-ID` and (2) non-atomic write on thread `unnamed-ID` at ALLOC
   --> tests/fail/data_race/atomic_read_na_write_race2.rs:LL:CC
    |
-LL |             *atomic_ref.get_mut() = 32;
-   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^ Data race detected between (1) atomic load on thread `unnamed-ID` and (2) non-atomic write on thread `unnamed-ID` at ALLOC. (2) just happened here
+LL | ...   *atomic_ref.get_mut() = 32;
+   |       ^^^^^^^^^^^^^^^^^^^^^^^^^^ (2) just happened here
    |
 help: and (1) occurred earlier here
   --> tests/fail/data_race/atomic_read_na_write_race2.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/data_race/atomic_write_na_read_race1.stderr b/src/tools/miri/tests/fail/data_race/atomic_write_na_read_race1.stderr
index fe65eca4bc6..dad28c38c17 100644
--- a/src/tools/miri/tests/fail/data_race/atomic_write_na_read_race1.stderr
+++ b/src/tools/miri/tests/fail/data_race/atomic_write_na_read_race1.stderr
@@ -1,8 +1,8 @@
-error: Undefined Behavior: Data race detected between (1) atomic store on thread `unnamed-ID` and (2) non-atomic read on thread `unnamed-ID` at ALLOC. (2) just happened here
+error: Undefined Behavior: Data race detected between (1) atomic store on thread `unnamed-ID` and (2) non-atomic read on thread `unnamed-ID` at ALLOC
   --> tests/fail/data_race/atomic_write_na_read_race1.rs:LL:CC
    |
-LL |             *atomic_ref.get_mut()
-   |             ^^^^^^^^^^^^^^^^^^^^^ Data race detected between (1) atomic store on thread `unnamed-ID` and (2) non-atomic read on thread `unnamed-ID` at ALLOC. (2) just happened here
+LL | ...   *atomic_ref.get_mut()
+   |       ^^^^^^^^^^^^^^^^^^^^^ (2) just happened here
    |
 help: and (1) occurred earlier here
   --> tests/fail/data_race/atomic_write_na_read_race1.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/data_race/atomic_write_na_read_race2.stderr b/src/tools/miri/tests/fail/data_race/atomic_write_na_read_race2.stderr
index 4393cc3c093..b2b121b3188 100644
--- a/src/tools/miri/tests/fail/data_race/atomic_write_na_read_race2.stderr
+++ b/src/tools/miri/tests/fail/data_race/atomic_write_na_read_race2.stderr
@@ -1,8 +1,8 @@
-error: Undefined Behavior: Data race detected between (1) non-atomic read on thread `unnamed-ID` and (2) atomic store on thread `unnamed-ID` at ALLOC. (2) just happened here
+error: Undefined Behavior: Data race detected between (1) non-atomic read on thread `unnamed-ID` and (2) atomic store on thread `unnamed-ID` at ALLOC
   --> tests/fail/data_race/atomic_write_na_read_race2.rs:LL:CC
    |
-LL |             (&*c.0).store(32, Ordering::SeqCst);
-   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Data race detected between (1) non-atomic read on thread `unnamed-ID` and (2) atomic store on thread `unnamed-ID` at ALLOC. (2) just happened here
+LL | ...   (&*c.0).store(32, Ordering::SeqCst);
+   |       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ (2) just happened here
    |
 help: and (1) occurred earlier here
   --> tests/fail/data_race/atomic_write_na_read_race2.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/data_race/atomic_write_na_write_race1.stderr b/src/tools/miri/tests/fail/data_race/atomic_write_na_write_race1.stderr
index 5a7f90447f0..2a115cb51d6 100644
--- a/src/tools/miri/tests/fail/data_race/atomic_write_na_write_race1.stderr
+++ b/src/tools/miri/tests/fail/data_race/atomic_write_na_write_race1.stderr
@@ -1,8 +1,8 @@
-error: Undefined Behavior: Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) atomic store on thread `unnamed-ID` at ALLOC. (2) just happened here
+error: Undefined Behavior: Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) atomic store on thread `unnamed-ID` at ALLOC
   --> tests/fail/data_race/atomic_write_na_write_race1.rs:LL:CC
    |
-LL |             (&*c.0).store(64, Ordering::SeqCst);
-   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) atomic store on thread `unnamed-ID` at ALLOC. (2) just happened here
+LL | ...   (&*c.0).store(64, Ordering::SeqCst);
+   |       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ (2) just happened here
    |
 help: and (1) occurred earlier here
   --> tests/fail/data_race/atomic_write_na_write_race1.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/data_race/atomic_write_na_write_race2.stderr b/src/tools/miri/tests/fail/data_race/atomic_write_na_write_race2.stderr
index 9ee4f16d0d5..54ad60cad1b 100644
--- a/src/tools/miri/tests/fail/data_race/atomic_write_na_write_race2.stderr
+++ b/src/tools/miri/tests/fail/data_race/atomic_write_na_write_race2.stderr
@@ -1,8 +1,8 @@
-error: Undefined Behavior: Data race detected between (1) atomic store on thread `unnamed-ID` and (2) non-atomic write on thread `unnamed-ID` at ALLOC. (2) just happened here
+error: Undefined Behavior: Data race detected between (1) atomic store on thread `unnamed-ID` and (2) non-atomic write on thread `unnamed-ID` at ALLOC
   --> tests/fail/data_race/atomic_write_na_write_race2.rs:LL:CC
    |
-LL |             *atomic_ref.get_mut() = 32;
-   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^ Data race detected between (1) atomic store on thread `unnamed-ID` and (2) non-atomic write on thread `unnamed-ID` at ALLOC. (2) just happened here
+LL | ...   *atomic_ref.get_mut() = 32;
+   |       ^^^^^^^^^^^^^^^^^^^^^^^^^^ (2) just happened here
    |
 help: and (1) occurred earlier here
   --> tests/fail/data_race/atomic_write_na_write_race2.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/data_race/dangling_thread_async_race.stderr b/src/tools/miri/tests/fail/data_race/dangling_thread_async_race.stderr
index 1051a1c51f2..0d026dddf81 100644
--- a/src/tools/miri/tests/fail/data_race/dangling_thread_async_race.stderr
+++ b/src/tools/miri/tests/fail/data_race/dangling_thread_async_race.stderr
@@ -1,8 +1,8 @@
-error: Undefined Behavior: Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) non-atomic write on thread `unnamed-ID` at ALLOC. (2) just happened here
+error: Undefined Behavior: Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) non-atomic write on thread `unnamed-ID` at ALLOC
   --> tests/fail/data_race/dangling_thread_async_race.rs:LL:CC
    |
-LL |             *c.0 = 64;
-   |             ^^^^^^^^^ Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) non-atomic write on thread `unnamed-ID` at ALLOC. (2) just happened here
+LL | ...   *c.0 = 64;
+   |       ^^^^^^^^^ (2) just happened here
    |
 help: and (1) occurred earlier here
   --> tests/fail/data_race/dangling_thread_async_race.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/data_race/dangling_thread_race.stderr b/src/tools/miri/tests/fail/data_race/dangling_thread_race.stderr
index 23a99ff6c8a..1c4e03a3257 100644
--- a/src/tools/miri/tests/fail/data_race/dangling_thread_race.stderr
+++ b/src/tools/miri/tests/fail/data_race/dangling_thread_race.stderr
@@ -1,8 +1,8 @@
-error: Undefined Behavior: Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) non-atomic write on thread `main` at ALLOC. (2) just happened here
+error: Undefined Behavior: Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) non-atomic write on thread `main` at ALLOC
   --> tests/fail/data_race/dangling_thread_race.rs:LL:CC
    |
-LL |         *c.0 = 64;
-   |         ^^^^^^^^^ Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) non-atomic write on thread `main` at ALLOC. (2) just happened here
+LL | ...   *c.0 = 64;
+   |       ^^^^^^^^^ (2) just happened here
    |
 help: and (1) occurred earlier here
   --> tests/fail/data_race/dangling_thread_race.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/data_race/dealloc_read_race1.stderr b/src/tools/miri/tests/fail/data_race/dealloc_read_race1.stderr
index 8eb4ebbcf72..55e4c4a0d9e 100644
--- a/src/tools/miri/tests/fail/data_race/dealloc_read_race1.stderr
+++ b/src/tools/miri/tests/fail/data_race/dealloc_read_race1.stderr
@@ -1,4 +1,4 @@
-error: Undefined Behavior: Data race detected between (1) non-atomic read on thread `unnamed-ID` and (2) deallocation on thread `unnamed-ID` at ALLOC. (2) just happened here
+error: Undefined Behavior: Data race detected between (1) non-atomic read on thread `unnamed-ID` and (2) deallocation on thread `unnamed-ID` at ALLOC
   --> tests/fail/data_race/dealloc_read_race1.rs:LL:CC
    |
 LL | /             __rust_dealloc(
@@ -7,7 +7,7 @@ LL | |                 ptr.0 as *mut _,
 LL | |                 std::mem::size_of::<usize>(),
 LL | |                 std::mem::align_of::<usize>(),
 LL | |             );
-   | |_____________^ Data race detected between (1) non-atomic read on thread `unnamed-ID` and (2) deallocation on thread `unnamed-ID` at ALLOC. (2) just happened here
+   | |_____________^ (2) just happened here
    |
 help: and (1) occurred earlier here
   --> tests/fail/data_race/dealloc_read_race1.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/data_race/dealloc_read_race2.stderr b/src/tools/miri/tests/fail/data_race/dealloc_read_race2.stderr
index 1a2b048572a..30d1fbbf6d8 100644
--- a/src/tools/miri/tests/fail/data_race/dealloc_read_race2.stderr
+++ b/src/tools/miri/tests/fail/data_race/dealloc_read_race2.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: memory access failed: ALLOC has been freed, so this p
   --> tests/fail/data_race/dealloc_read_race2.rs:LL:CC
    |
 LL |             *ptr.0
-   |             ^^^^^^ memory access failed: ALLOC has been freed, so this pointer is dangling
+   |             ^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/data_race/dealloc_read_race_stack.stderr b/src/tools/miri/tests/fail/data_race/dealloc_read_race_stack.stderr
index ce9719b1d46..ea8fd73393c 100644
--- a/src/tools/miri/tests/fail/data_race/dealloc_read_race_stack.stderr
+++ b/src/tools/miri/tests/fail/data_race/dealloc_read_race_stack.stderr
@@ -1,8 +1,8 @@
-error: Undefined Behavior: Data race detected between (1) non-atomic read on thread `unnamed-ID` and (2) deallocation on thread `unnamed-ID` at ALLOC. (2) just happened here
+error: Undefined Behavior: Data race detected between (1) non-atomic read on thread `unnamed-ID` and (2) deallocation on thread `unnamed-ID` at ALLOC
   --> tests/fail/data_race/dealloc_read_race_stack.rs:LL:CC
    |
 LL |             }
-   |             ^ Data race detected between (1) non-atomic read on thread `unnamed-ID` and (2) deallocation on thread `unnamed-ID` at ALLOC. (2) just happened here
+   |             ^ (2) just happened here
    |
 help: and (1) occurred earlier here
   --> tests/fail/data_race/dealloc_read_race_stack.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/data_race/dealloc_write_race1.stderr b/src/tools/miri/tests/fail/data_race/dealloc_write_race1.stderr
index 48d974241aa..b306f181231 100644
--- a/src/tools/miri/tests/fail/data_race/dealloc_write_race1.stderr
+++ b/src/tools/miri/tests/fail/data_race/dealloc_write_race1.stderr
@@ -1,4 +1,4 @@
-error: Undefined Behavior: Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) deallocation on thread `unnamed-ID` at ALLOC. (2) just happened here
+error: Undefined Behavior: Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) deallocation on thread `unnamed-ID` at ALLOC
   --> tests/fail/data_race/dealloc_write_race1.rs:LL:CC
    |
 LL | /             __rust_dealloc(
@@ -7,7 +7,7 @@ LL | |                 ptr.0 as *mut _,
 LL | |                 std::mem::size_of::<usize>(),
 LL | |                 std::mem::align_of::<usize>(),
 LL | |             );
-   | |_____________^ Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) deallocation on thread `unnamed-ID` at ALLOC. (2) just happened here
+   | |_____________^ (2) just happened here
    |
 help: and (1) occurred earlier here
   --> tests/fail/data_race/dealloc_write_race1.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/data_race/dealloc_write_race2.stderr b/src/tools/miri/tests/fail/data_race/dealloc_write_race2.stderr
index 077d4588266..8a337dbc77c 100644
--- a/src/tools/miri/tests/fail/data_race/dealloc_write_race2.stderr
+++ b/src/tools/miri/tests/fail/data_race/dealloc_write_race2.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: memory access failed: ALLOC has been freed, so this p
   --> tests/fail/data_race/dealloc_write_race2.rs:LL:CC
    |
 LL |             *ptr.0 = 2;
-   |             ^^^^^^^^^^ memory access failed: ALLOC has been freed, so this pointer is dangling
+   |             ^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/data_race/dealloc_write_race_stack.stderr b/src/tools/miri/tests/fail/data_race/dealloc_write_race_stack.stderr
index 2b531b6440c..f3a8707ed14 100644
--- a/src/tools/miri/tests/fail/data_race/dealloc_write_race_stack.stderr
+++ b/src/tools/miri/tests/fail/data_race/dealloc_write_race_stack.stderr
@@ -1,8 +1,8 @@
-error: Undefined Behavior: Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) deallocation on thread `unnamed-ID` at ALLOC. (2) just happened here
+error: Undefined Behavior: Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) deallocation on thread `unnamed-ID` at ALLOC
   --> tests/fail/data_race/dealloc_write_race_stack.rs:LL:CC
    |
 LL |             }
-   |             ^ Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) deallocation on thread `unnamed-ID` at ALLOC. (2) just happened here
+   |             ^ (2) just happened here
    |
 help: and (1) occurred earlier here
   --> tests/fail/data_race/dealloc_write_race_stack.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/data_race/enable_after_join_to_main.stderr b/src/tools/miri/tests/fail/data_race/enable_after_join_to_main.stderr
index 5d5d1c8cc68..c6db02fa5ae 100644
--- a/src/tools/miri/tests/fail/data_race/enable_after_join_to_main.stderr
+++ b/src/tools/miri/tests/fail/data_race/enable_after_join_to_main.stderr
@@ -1,8 +1,8 @@
-error: Undefined Behavior: Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) non-atomic write on thread `unnamed-ID` at ALLOC. (2) just happened here
+error: Undefined Behavior: Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) non-atomic write on thread `unnamed-ID` at ALLOC
   --> tests/fail/data_race/enable_after_join_to_main.rs:LL:CC
    |
-LL |             *c.0 = 64;
-   |             ^^^^^^^^^ Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) non-atomic write on thread `unnamed-ID` at ALLOC. (2) just happened here
+LL | ...   *c.0 = 64;
+   |       ^^^^^^^^^ (2) just happened here
    |
 help: and (1) occurred earlier here
   --> tests/fail/data_race/enable_after_join_to_main.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/data_race/fence_after_load.stderr b/src/tools/miri/tests/fail/data_race/fence_after_load.stderr
index 03b3c6f8f0b..890bacd58d4 100644
--- a/src/tools/miri/tests/fail/data_race/fence_after_load.stderr
+++ b/src/tools/miri/tests/fail/data_race/fence_after_load.stderr
@@ -1,8 +1,8 @@
-error: Undefined Behavior: Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) non-atomic write on thread `main` at ALLOC. (2) just happened here
+error: Undefined Behavior: Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) non-atomic write on thread `main` at ALLOC
   --> tests/fail/data_race/fence_after_load.rs:LL:CC
    |
 LL |     unsafe { V = 2 }
-   |              ^^^^^ Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) non-atomic write on thread `main` at ALLOC. (2) just happened here
+   |              ^^^^^ (2) just happened here
    |
 help: and (1) occurred earlier here
   --> tests/fail/data_race/fence_after_load.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/data_race/local_variable_alloc_race.stderr b/src/tools/miri/tests/fail/data_race/local_variable_alloc_race.stderr
index 51a4c5cea30..ea2bf3fc9f2 100644
--- a/src/tools/miri/tests/fail/data_race/local_variable_alloc_race.stderr
+++ b/src/tools/miri/tests/fail/data_race/local_variable_alloc_race.stderr
@@ -1,8 +1,8 @@
-error: Undefined Behavior: Data race detected between (1) creating a new allocation on thread `main` and (2) non-atomic write on thread `unnamed-ID` at ALLOC. (2) just happened here
+error: Undefined Behavior: Data race detected between (1) creating a new allocation on thread `main` and (2) non-atomic write on thread `unnamed-ID` at ALLOC
   --> tests/fail/data_race/local_variable_alloc_race.rs:LL:CC
    |
 LL |             *ptr = 127;
-   |             ^^^^^^^^^^ Data race detected between (1) creating a new allocation on thread `main` and (2) non-atomic write on thread `unnamed-ID` at ALLOC. (2) just happened here
+   |             ^^^^^^^^^^ (2) just happened here
    |
 help: and (1) occurred earlier here
   --> tests/fail/data_race/local_variable_alloc_race.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/data_race/local_variable_read_race.stderr b/src/tools/miri/tests/fail/data_race/local_variable_read_race.stderr
index 3faffd4131e..215842d1815 100644
--- a/src/tools/miri/tests/fail/data_race/local_variable_read_race.stderr
+++ b/src/tools/miri/tests/fail/data_race/local_variable_read_race.stderr
@@ -1,8 +1,8 @@
-error: Undefined Behavior: Data race detected between (1) non-atomic read on thread `main` and (2) non-atomic write on thread `unnamed-ID` at ALLOC. (2) just happened here
+error: Undefined Behavior: Data race detected between (1) non-atomic read on thread `main` and (2) non-atomic write on thread `unnamed-ID` at ALLOC
   --> tests/fail/data_race/local_variable_read_race.rs:LL:CC
    |
 LL |             *ptr = 127;
-   |             ^^^^^^^^^^ Data race detected between (1) non-atomic read on thread `main` and (2) non-atomic write on thread `unnamed-ID` at ALLOC. (2) just happened here
+   |             ^^^^^^^^^^ (2) just happened here
    |
 help: and (1) occurred earlier here
   --> tests/fail/data_race/local_variable_read_race.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/data_race/local_variable_write_race.stderr b/src/tools/miri/tests/fail/data_race/local_variable_write_race.stderr
index 24bbe227f9e..ce0c22561da 100644
--- a/src/tools/miri/tests/fail/data_race/local_variable_write_race.stderr
+++ b/src/tools/miri/tests/fail/data_race/local_variable_write_race.stderr
@@ -1,8 +1,8 @@
-error: Undefined Behavior: Data race detected between (1) non-atomic write on thread `main` and (2) non-atomic write on thread `unnamed-ID` at ALLOC. (2) just happened here
+error: Undefined Behavior: Data race detected between (1) non-atomic write on thread `main` and (2) non-atomic write on thread `unnamed-ID` at ALLOC
   --> tests/fail/data_race/local_variable_write_race.rs:LL:CC
    |
 LL |             *ptr = 127;
-   |             ^^^^^^^^^^ Data race detected between (1) non-atomic write on thread `main` and (2) non-atomic write on thread `unnamed-ID` at ALLOC. (2) just happened here
+   |             ^^^^^^^^^^ (2) just happened here
    |
 help: and (1) occurred earlier here
   --> tests/fail/data_race/local_variable_write_race.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/data_race/mixed_size_read_read_write.match_first_load.stderr b/src/tools/miri/tests/fail/data_race/mixed_size_read_read_write.match_first_load.stderr
index b829627c00a..ba714868d01 100644
--- a/src/tools/miri/tests/fail/data_race/mixed_size_read_read_write.match_first_load.stderr
+++ b/src/tools/miri/tests/fail/data_race/mixed_size_read_read_write.match_first_load.stderr
@@ -1,8 +1,8 @@
-error: Undefined Behavior: Race condition detected between (1) multiple differently-sized atomic loads, including one load on thread `unnamed-ID` and (2) 2-byte atomic store on thread `unnamed-ID` at ALLOC. (2) just happened here
+error: Undefined Behavior: Race condition detected between (1) multiple differently-sized atomic loads, including one load on thread `unnamed-ID` and (2) 2-byte atomic store on thread `unnamed-ID` at ALLOC
   --> tests/fail/data_race/mixed_size_read_read_write.rs:LL:CC
    |
 LL |                 a16.store(0, Ordering::SeqCst);
-   |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Race condition detected between (1) multiple differently-sized atomic loads, including one load on thread `unnamed-ID` and (2) 2-byte atomic store on thread `unnamed-ID` at ALLOC. (2) just happened here
+   |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ (2) just happened here
    |
 help: and (1) occurred earlier here
   --> tests/fail/data_race/mixed_size_read_read_write.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/data_race/mixed_size_read_read_write.match_second_load.stderr b/src/tools/miri/tests/fail/data_race/mixed_size_read_read_write.match_second_load.stderr
index 6bc38b14cb2..13749cc349e 100644
--- a/src/tools/miri/tests/fail/data_race/mixed_size_read_read_write.match_second_load.stderr
+++ b/src/tools/miri/tests/fail/data_race/mixed_size_read_read_write.match_second_load.stderr
@@ -1,8 +1,8 @@
-error: Undefined Behavior: Race condition detected between (1) multiple differently-sized atomic loads, including one load on thread `unnamed-ID` and (2) 1-byte atomic store on thread `unnamed-ID` at ALLOC. (2) just happened here
+error: Undefined Behavior: Race condition detected between (1) multiple differently-sized atomic loads, including one load on thread `unnamed-ID` and (2) 1-byte atomic store on thread `unnamed-ID` at ALLOC
   --> tests/fail/data_race/mixed_size_read_read_write.rs:LL:CC
    |
 LL |                 a8[0].store(0, Ordering::SeqCst);
-   |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Race condition detected between (1) multiple differently-sized atomic loads, including one load on thread `unnamed-ID` and (2) 1-byte atomic store on thread `unnamed-ID` at ALLOC. (2) just happened here
+   |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ (2) just happened here
    |
 help: and (1) occurred earlier here
   --> tests/fail/data_race/mixed_size_read_read_write.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/data_race/mixed_size_read_write.read_write.stderr b/src/tools/miri/tests/fail/data_race/mixed_size_read_write.read_write.stderr
index 6f8dbd38ca8..11c66554fae 100644
--- a/src/tools/miri/tests/fail/data_race/mixed_size_read_write.read_write.stderr
+++ b/src/tools/miri/tests/fail/data_race/mixed_size_read_write.read_write.stderr
@@ -1,8 +1,8 @@
-error: Undefined Behavior: Race condition detected between (1) 1-byte atomic load on thread `unnamed-ID` and (2) 2-byte atomic store on thread `unnamed-ID` at ALLOC. (2) just happened here
+error: Undefined Behavior: Race condition detected between (1) 1-byte atomic load on thread `unnamed-ID` and (2) 2-byte atomic store on thread `unnamed-ID` at ALLOC
   --> tests/fail/data_race/mixed_size_read_write.rs:LL:CC
    |
 LL |             a16.store(1, Ordering::SeqCst);
-   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Race condition detected between (1) 1-byte atomic load on thread `unnamed-ID` and (2) 2-byte atomic store on thread `unnamed-ID` at ALLOC. (2) just happened here
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ (2) just happened here
    |
 help: and (1) occurred earlier here
   --> tests/fail/data_race/mixed_size_read_write.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/data_race/mixed_size_read_write.write_read.stderr b/src/tools/miri/tests/fail/data_race/mixed_size_read_write.write_read.stderr
index 990d2058bca..4fa08032f44 100644
--- a/src/tools/miri/tests/fail/data_race/mixed_size_read_write.write_read.stderr
+++ b/src/tools/miri/tests/fail/data_race/mixed_size_read_write.write_read.stderr
@@ -1,8 +1,8 @@
-error: Undefined Behavior: Race condition detected between (1) 2-byte atomic store on thread `unnamed-ID` and (2) 1-byte atomic load on thread `unnamed-ID` at ALLOC. (2) just happened here
+error: Undefined Behavior: Race condition detected between (1) 2-byte atomic store on thread `unnamed-ID` and (2) 1-byte atomic load on thread `unnamed-ID` at ALLOC
   --> tests/fail/data_race/mixed_size_read_write.rs:LL:CC
    |
 LL |             a8[0].load(Ordering::SeqCst);
-   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Race condition detected between (1) 2-byte atomic store on thread `unnamed-ID` and (2) 1-byte atomic load on thread `unnamed-ID` at ALLOC. (2) just happened here
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ (2) just happened here
    |
 help: and (1) occurred earlier here
   --> tests/fail/data_race/mixed_size_read_write.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/data_race/mixed_size_write_write.fst.stderr b/src/tools/miri/tests/fail/data_race/mixed_size_write_write.fst.stderr
index a353910dcc9..26eddd3f193 100644
--- a/src/tools/miri/tests/fail/data_race/mixed_size_write_write.fst.stderr
+++ b/src/tools/miri/tests/fail/data_race/mixed_size_write_write.fst.stderr
@@ -1,8 +1,8 @@
-error: Undefined Behavior: Race condition detected between (1) 2-byte atomic store on thread `unnamed-ID` and (2) 1-byte atomic store on thread `unnamed-ID` at ALLOC. (2) just happened here
+error: Undefined Behavior: Race condition detected between (1) 2-byte atomic store on thread `unnamed-ID` and (2) 1-byte atomic store on thread `unnamed-ID` at ALLOC
   --> tests/fail/data_race/mixed_size_write_write.rs:LL:CC
    |
 LL |             a8[idx].store(1, Ordering::SeqCst);
-   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Race condition detected between (1) 2-byte atomic store on thread `unnamed-ID` and (2) 1-byte atomic store on thread `unnamed-ID` at ALLOC. (2) just happened here
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ (2) just happened here
    |
 help: and (1) occurred earlier here
   --> tests/fail/data_race/mixed_size_write_write.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/data_race/mixed_size_write_write.snd.stderr b/src/tools/miri/tests/fail/data_race/mixed_size_write_write.snd.stderr
index 3b9c0491502..e0ca0145606 100644
--- a/src/tools/miri/tests/fail/data_race/mixed_size_write_write.snd.stderr
+++ b/src/tools/miri/tests/fail/data_race/mixed_size_write_write.snd.stderr
@@ -1,8 +1,8 @@
-error: Undefined Behavior: Race condition detected between (1) 2-byte atomic store on thread `unnamed-ID` and (2) 1-byte atomic store on thread `unnamed-ID` at ALLOC+0x1. (2) just happened here
+error: Undefined Behavior: Race condition detected between (1) 2-byte atomic store on thread `unnamed-ID` and (2) 1-byte atomic store on thread `unnamed-ID` at ALLOC+0x1
   --> tests/fail/data_race/mixed_size_write_write.rs:LL:CC
    |
 LL |             a8[idx].store(1, Ordering::SeqCst);
-   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Race condition detected between (1) 2-byte atomic store on thread `unnamed-ID` and (2) 1-byte atomic store on thread `unnamed-ID` at ALLOC+0x1. (2) just happened here
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ (2) just happened here
    |
 help: and (1) occurred earlier here
   --> tests/fail/data_race/mixed_size_write_write.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/data_race/read_write_race.stderr b/src/tools/miri/tests/fail/data_race/read_write_race.stderr
index eac5a0c8a6c..c0754f6db4c 100644
--- a/src/tools/miri/tests/fail/data_race/read_write_race.stderr
+++ b/src/tools/miri/tests/fail/data_race/read_write_race.stderr
@@ -1,8 +1,8 @@
-error: Undefined Behavior: Data race detected between (1) non-atomic read on thread `unnamed-ID` and (2) non-atomic write on thread `unnamed-ID` at ALLOC. (2) just happened here
+error: Undefined Behavior: Data race detected between (1) non-atomic read on thread `unnamed-ID` and (2) non-atomic write on thread `unnamed-ID` at ALLOC
   --> tests/fail/data_race/read_write_race.rs:LL:CC
    |
-LL |             *c.0 = 64;
-   |             ^^^^^^^^^ Data race detected between (1) non-atomic read on thread `unnamed-ID` and (2) non-atomic write on thread `unnamed-ID` at ALLOC. (2) just happened here
+LL | ...   *c.0 = 64;
+   |       ^^^^^^^^^ (2) just happened here
    |
 help: and (1) occurred earlier here
   --> tests/fail/data_race/read_write_race.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/data_race/read_write_race_stack.stderr b/src/tools/miri/tests/fail/data_race/read_write_race_stack.stderr
index 9af78bc79a3..3f6b042de56 100644
--- a/src/tools/miri/tests/fail/data_race/read_write_race_stack.stderr
+++ b/src/tools/miri/tests/fail/data_race/read_write_race_stack.stderr
@@ -1,8 +1,8 @@
-error: Undefined Behavior: Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) non-atomic read on thread `unnamed-ID` at ALLOC. (2) just happened here
+error: Undefined Behavior: Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) non-atomic read on thread `unnamed-ID` at ALLOC
   --> tests/fail/data_race/read_write_race_stack.rs:LL:CC
    |
-LL |             stack_var
-   |             ^^^^^^^^^ Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) non-atomic read on thread `unnamed-ID` at ALLOC. (2) just happened here
+LL | ...   stack_var
+   |       ^^^^^^^^^ (2) just happened here
    |
 help: and (1) occurred earlier here
   --> tests/fail/data_race/read_write_race_stack.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/data_race/relax_acquire_race.stderr b/src/tools/miri/tests/fail/data_race/relax_acquire_race.stderr
index a358d8da364..fdd8971f607 100644
--- a/src/tools/miri/tests/fail/data_race/relax_acquire_race.stderr
+++ b/src/tools/miri/tests/fail/data_race/relax_acquire_race.stderr
@@ -1,8 +1,8 @@
-error: Undefined Behavior: Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) non-atomic read on thread `unnamed-ID` at ALLOC. (2) just happened here
+error: Undefined Behavior: Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) non-atomic read on thread `unnamed-ID` at ALLOC
   --> tests/fail/data_race/relax_acquire_race.rs:LL:CC
    |
-LL |                 *c.0
-   |                 ^^^^ Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) non-atomic read on thread `unnamed-ID` at ALLOC. (2) just happened here
+LL | ...   *c.0
+   |       ^^^^ (2) just happened here
    |
 help: and (1) occurred earlier here
   --> tests/fail/data_race/relax_acquire_race.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/data_race/release_seq_race.stderr b/src/tools/miri/tests/fail/data_race/release_seq_race.stderr
index f47e463dd63..2ee859dc45c 100644
--- a/src/tools/miri/tests/fail/data_race/release_seq_race.stderr
+++ b/src/tools/miri/tests/fail/data_race/release_seq_race.stderr
@@ -1,8 +1,8 @@
-error: Undefined Behavior: Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) non-atomic read on thread `unnamed-ID` at ALLOC. (2) just happened here
+error: Undefined Behavior: Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) non-atomic read on thread `unnamed-ID` at ALLOC
   --> tests/fail/data_race/release_seq_race.rs:LL:CC
    |
-LL |                 *c.0
-   |                 ^^^^ Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) non-atomic read on thread `unnamed-ID` at ALLOC. (2) just happened here
+LL | ...   *c.0
+   |       ^^^^ (2) just happened here
    |
 help: and (1) occurred earlier here
   --> tests/fail/data_race/release_seq_race.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/data_race/release_seq_race_same_thread.stderr b/src/tools/miri/tests/fail/data_race/release_seq_race_same_thread.stderr
index 2d26d4cf68a..74b84468913 100644
--- a/src/tools/miri/tests/fail/data_race/release_seq_race_same_thread.stderr
+++ b/src/tools/miri/tests/fail/data_race/release_seq_race_same_thread.stderr
@@ -1,8 +1,8 @@
-error: Undefined Behavior: Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) non-atomic read on thread `unnamed-ID` at ALLOC. (2) just happened here
+error: Undefined Behavior: Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) non-atomic read on thread `unnamed-ID` at ALLOC
   --> tests/fail/data_race/release_seq_race_same_thread.rs:LL:CC
    |
-LL |                 *c.0
-   |                 ^^^^ Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) non-atomic read on thread `unnamed-ID` at ALLOC. (2) just happened here
+LL | ...   *c.0
+   |       ^^^^ (2) just happened here
    |
 help: and (1) occurred earlier here
   --> tests/fail/data_race/release_seq_race_same_thread.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/data_race/rmw_race.stderr b/src/tools/miri/tests/fail/data_race/rmw_race.stderr
index 4a991db32d6..a9a97a3a3e7 100644
--- a/src/tools/miri/tests/fail/data_race/rmw_race.stderr
+++ b/src/tools/miri/tests/fail/data_race/rmw_race.stderr
@@ -1,8 +1,8 @@
-error: Undefined Behavior: Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) non-atomic read on thread `unnamed-ID` at ALLOC. (2) just happened here
+error: Undefined Behavior: Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) non-atomic read on thread `unnamed-ID` at ALLOC
   --> tests/fail/data_race/rmw_race.rs:LL:CC
    |
-LL |                 *c.0
-   |                 ^^^^ Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) non-atomic read on thread `unnamed-ID` at ALLOC. (2) just happened here
+LL | ...   *c.0
+   |       ^^^^ (2) just happened here
    |
 help: and (1) occurred earlier here
   --> tests/fail/data_race/rmw_race.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/data_race/stack_pop_race.stderr b/src/tools/miri/tests/fail/data_race/stack_pop_race.stderr
index 721b7563044..3ba949bf967 100644
--- a/src/tools/miri/tests/fail/data_race/stack_pop_race.stderr
+++ b/src/tools/miri/tests/fail/data_race/stack_pop_race.stderr
@@ -1,8 +1,8 @@
-error: Undefined Behavior: Data race detected between (1) non-atomic read on thread `unnamed-ID` and (2) deallocation on thread `main` at ALLOC. (2) just happened here
+error: Undefined Behavior: Data race detected between (1) non-atomic read on thread `unnamed-ID` and (2) deallocation on thread `main` at ALLOC
   --> tests/fail/data_race/stack_pop_race.rs:LL:CC
    |
 LL |     race(0);
-   |     ^^^^^^^ Data race detected between (1) non-atomic read on thread `unnamed-ID` and (2) deallocation on thread `main` at ALLOC. (2) just happened here
+   |     ^^^^^^^ (2) just happened here
    |
 help: and (1) occurred earlier here
   --> tests/fail/data_race/stack_pop_race.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/data_race/write_write_race.stderr b/src/tools/miri/tests/fail/data_race/write_write_race.stderr
index 2ea54421b89..314ea608190 100644
--- a/src/tools/miri/tests/fail/data_race/write_write_race.stderr
+++ b/src/tools/miri/tests/fail/data_race/write_write_race.stderr
@@ -1,8 +1,8 @@
-error: Undefined Behavior: Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) non-atomic write on thread `unnamed-ID` at ALLOC. (2) just happened here
+error: Undefined Behavior: Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) non-atomic write on thread `unnamed-ID` at ALLOC
   --> tests/fail/data_race/write_write_race.rs:LL:CC
    |
-LL |             *c.0 = 64;
-   |             ^^^^^^^^^ Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) non-atomic write on thread `unnamed-ID` at ALLOC. (2) just happened here
+LL | ...   *c.0 = 64;
+   |       ^^^^^^^^^ (2) just happened here
    |
 help: and (1) occurred earlier here
   --> tests/fail/data_race/write_write_race.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/data_race/write_write_race_stack.stderr b/src/tools/miri/tests/fail/data_race/write_write_race_stack.stderr
index 0cd9de11318..71334019f6b 100644
--- a/src/tools/miri/tests/fail/data_race/write_write_race_stack.stderr
+++ b/src/tools/miri/tests/fail/data_race/write_write_race_stack.stderr
@@ -1,8 +1,8 @@
-error: Undefined Behavior: Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) non-atomic write on thread `unnamed-ID` at ALLOC. (2) just happened here
+error: Undefined Behavior: Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) non-atomic write on thread `unnamed-ID` at ALLOC
   --> tests/fail/data_race/write_write_race_stack.rs:LL:CC
    |
-LL |             stack_var = 1usize;
-   |             ^^^^^^^^^^^^^^^^^^ Data race detected between (1) non-atomic write on thread `unnamed-ID` and (2) non-atomic write on thread `unnamed-ID` at ALLOC. (2) just happened here
+LL | ...   stack_var = 1usize;
+   |       ^^^^^^^^^^^^^^^^^^ (2) just happened here
    |
 help: and (1) occurred earlier here
   --> tests/fail/data_race/write_write_race_stack.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/dyn-call-trait-mismatch.stderr b/src/tools/miri/tests/fail/dyn-call-trait-mismatch.stderr
index 37d102c8713..3cb917d39fd 100644
--- a/src/tools/miri/tests/fail/dyn-call-trait-mismatch.stderr
+++ b/src/tools/miri/tests/fail/dyn-call-trait-mismatch.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: using vtable for `T1` but `T2` was expected
   --> tests/fail/dyn-call-trait-mismatch.rs:LL:CC
    |
 LL |     r2.method2();
-   |     ^^^^^^^^^^^^ using vtable for `T1` but `T2` was expected
+   |     ^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/dyn-upcast-nop-wrong-trait.stderr b/src/tools/miri/tests/fail/dyn-upcast-nop-wrong-trait.stderr
index 54d9d385e96..bf7fc7ed8a2 100644
--- a/src/tools/miri/tests/fail/dyn-upcast-nop-wrong-trait.stderr
+++ b/src/tools/miri/tests/fail/dyn-upcast-nop-wrong-trait.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value: wrong trait in wide point
   --> tests/fail/dyn-upcast-nop-wrong-trait.rs:LL:CC
    |
 LL |     let ptr: *const (dyn fmt::Debug + Send + Sync) = unsafe { std::mem::transmute(ptr) };
-   |                                                               ^^^^^^^^^^^^^^^^^^^^^^^^ constructing invalid value: wrong trait in wide pointer vtable: expected `std::fmt::Debug + std::marker::Send + std::marker::Sync`, but encountered `std::fmt::Display`
+   |                                                               ^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/dyn-upcast-trait-mismatch.stderr b/src/tools/miri/tests/fail/dyn-upcast-trait-mismatch.stderr
index d0fd0e6fcc1..f5e72e6ee0f 100644
--- a/src/tools/miri/tests/fail/dyn-upcast-trait-mismatch.stderr
+++ b/src/tools/miri/tests/fail/dyn-upcast-trait-mismatch.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: using vtable for `Baz` but `Bar` was expected
   --> tests/fail/dyn-upcast-trait-mismatch.rs:LL:CC
    |
 LL |         let _err = baz_fake as *const dyn Foo;
-   |                    ^^^^^^^^^^^^^^^^^^^^^^^^^^ using vtable for `Baz` but `Bar` was expected
+   |                    ^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/enum-set-discriminant-niche-variant-wrong.stderr b/src/tools/miri/tests/fail/enum-set-discriminant-niche-variant-wrong.stderr
index 4e2b9c03eae..f3ec20837d3 100644
--- a/src/tools/miri/tests/fail/enum-set-discriminant-niche-variant-wrong.stderr
+++ b/src/tools/miri/tests/fail/enum-set-discriminant-niche-variant-wrong.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: trying to set discriminant of a Option<std::num::NonZ
   --> tests/fail/enum-set-discriminant-niche-variant-wrong.rs:LL:CC
    |
 LL |             SetDiscriminant(*ptr, 1);
-   |             ^^^^^^^^^^^^^^^^^^^^^^^^ trying to set discriminant of a Option<std::num::NonZero<i32>> to the niched variant, but the value does not match
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/enum-untagged-variant-invalid-encoding.stderr b/src/tools/miri/tests/fail/enum-untagged-variant-invalid-encoding.stderr
index 759dbc36380..2099041c6ce 100644
--- a/src/tools/miri/tests/fail/enum-untagged-variant-invalid-encoding.stderr
+++ b/src/tools/miri/tests/fail/enum-untagged-variant-invalid-encoding.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: enum value has invalid tag: 0x03
   --> tests/fail/enum-untagged-variant-invalid-encoding.rs:LL:CC
    |
 LL |         assert!(matches!(invalid, Foo::Var2(_)));
-   |                          ^^^^^^^ enum value has invalid tag: 0x03
+   |                          ^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/environ-gets-deallocated.stderr b/src/tools/miri/tests/fail/environ-gets-deallocated.stderr
index bb3fe1cec73..fcc5a8d2c80 100644
--- a/src/tools/miri/tests/fail/environ-gets-deallocated.stderr
+++ b/src/tools/miri/tests/fail/environ-gets-deallocated.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: memory access failed: ALLOC has been freed, so this p
   --> tests/fail/environ-gets-deallocated.rs:LL:CC
    |
 LL |     let _y = unsafe { *pointer };
-   |                       ^^^^^^^^ memory access failed: ALLOC has been freed, so this pointer is dangling
+   |                       ^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/extern-type-field-offset.stderr b/src/tools/miri/tests/fail/extern-type-field-offset.stderr
index 1ed440c7a33..90f104ec298 100644
--- a/src/tools/miri/tests/fail/extern-type-field-offset.stderr
+++ b/src/tools/miri/tests/fail/extern-type-field-offset.stderr
@@ -1,8 +1,8 @@
-warning: reborrow of reference to `extern type`
+warning: reborrow of a reference to `extern type` is not properly supported
   --> tests/fail/extern-type-field-offset.rs:LL:CC
    |
 LL |     let x: &Newtype = unsafe { &*(&buf as *const _ as *const Newtype) };
-   |                                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ reborrow of a reference to `extern type` is not properly supported
+   |                                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ reborrow of reference to `extern type`
    |
    = help: `extern type` are not compatible with the Stacked Borrows aliasing model implemented by Miri; Miri may miss bugs in this code
    = help: try running with `MIRIFLAGS=-Zmiri-tree-borrows` to use the more permissive but also even more experimental Tree Borrows aliasing checks instead
@@ -13,7 +13,7 @@ error: unsupported operation: `extern type` field does not have a known offset
   --> tests/fail/extern-type-field-offset.rs:LL:CC
    |
 LL |     let _field = &x.a;
-   |                  ^^^^ `extern type` field does not have a known offset
+   |                  ^^^^ unsupported operation occurred here
    |
    = help: this is likely not a bug in the program; it indicates that the program performed an operation that Miri does not support
    = note: BACKTRACE:
diff --git a/src/tools/miri/tests/fail/extern_static.stderr b/src/tools/miri/tests/fail/extern_static.stderr
index c0bedbbcbf9..5bc835cfcc0 100644
--- a/src/tools/miri/tests/fail/extern_static.stderr
+++ b/src/tools/miri/tests/fail/extern_static.stderr
@@ -2,7 +2,7 @@ error: unsupported operation: extern static `FOO` is not supported by Miri
   --> tests/fail/extern_static.rs:LL:CC
    |
 LL |     let _val = std::ptr::addr_of!(FOO);
-   |                                   ^^^ extern static `FOO` is not supported by Miri
+   |                                   ^^^ unsupported operation occurred here
    |
    = help: this is likely not a bug in the program; it indicates that the program performed an operation that Miri does not support
    = note: BACKTRACE:
diff --git a/src/tools/miri/tests/fail/extern_static_in_const.stderr b/src/tools/miri/tests/fail/extern_static_in_const.stderr
index 067a2a2b643..deca69060ac 100644
--- a/src/tools/miri/tests/fail/extern_static_in_const.stderr
+++ b/src/tools/miri/tests/fail/extern_static_in_const.stderr
@@ -2,7 +2,7 @@ error: unsupported operation: extern static `E` is not supported by Miri
   --> tests/fail/extern_static_in_const.rs:LL:CC
    |
 LL |     let _val = X;
-   |                ^ extern static `E` is not supported by Miri
+   |                ^ unsupported operation occurred here
    |
    = help: this is likely not a bug in the program; it indicates that the program performed an operation that Miri does not support
    = note: BACKTRACE:
diff --git a/src/tools/miri/tests/fail/extern_static_wrong_size.stderr b/src/tools/miri/tests/fail/extern_static_wrong_size.stderr
index 1af84e23682..fce4ff9ad1f 100644
--- a/src/tools/miri/tests/fail/extern_static_wrong_size.stderr
+++ b/src/tools/miri/tests/fail/extern_static_wrong_size.stderr
@@ -2,7 +2,7 @@ error: unsupported operation: extern static `environ` has been declared as `exte
   --> tests/fail/extern_static_wrong_size.rs:LL:CC
    |
 LL |     let _val = unsafe { environ };
-   |                         ^^^^^^^ extern static `environ` has been declared as `extern_static_wrong_size::environ` with a size of 1 bytes and alignment of 1 bytes, but Miri emulates it via an extern static shim with a size of N bytes and alignment of N bytes
+   |                         ^^^^^^^ unsupported operation occurred here
    |
    = help: this is likely not a bug in the program; it indicates that the program performed an operation that Miri does not support
    = note: BACKTRACE:
diff --git a/src/tools/miri/tests/fail/function_calls/arg_inplace_mutate.stack.stderr b/src/tools/miri/tests/fail/function_calls/arg_inplace_mutate.stack.stderr
index 2875a5be285..8a454bedb28 100644
--- a/src/tools/miri/tests/fail/function_calls/arg_inplace_mutate.stack.stderr
+++ b/src/tools/miri/tests/fail/function_calls/arg_inplace_mutate.stack.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: not granting access to tag <TAG> because that would r
   --> tests/fail/function_calls/arg_inplace_mutate.rs:LL:CC
    |
 LL |     unsafe { ptr.write(S(0)) };
-   |              ^^^^^^^^^^^^^^^ not granting access to tag <TAG> because that would remove [Unique for <TAG>] which is strongly protected
+   |              ^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/function_calls/arg_inplace_mutate.tree.stderr b/src/tools/miri/tests/fail/function_calls/arg_inplace_mutate.tree.stderr
index c699987b796..2f1dc1988f5 100644
--- a/src/tools/miri/tests/fail/function_calls/arg_inplace_mutate.tree.stderr
+++ b/src/tools/miri/tests/fail/function_calls/arg_inplace_mutate.tree.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: write access through <TAG> (root of the allocation) a
   --> tests/fail/function_calls/arg_inplace_mutate.rs:LL:CC
    |
 LL |     unsafe { ptr.write(S(0)) };
-   |              ^^^^^^^^^^^^^^^ write access through <TAG> (root of the allocation) at ALLOC[0x0] is forbidden
+   |              ^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> (root of the allocation) is foreign to the protected tag <TAG> (i.e., it is not a child)
diff --git a/src/tools/miri/tests/fail/function_calls/arg_inplace_observe_after.stderr b/src/tools/miri/tests/fail/function_calls/arg_inplace_observe_after.stderr
index 7fd71c60847..6a7d9a495f9 100644
--- a/src/tools/miri/tests/fail/function_calls/arg_inplace_observe_after.stderr
+++ b/src/tools/miri/tests/fail/function_calls/arg_inplace_observe_after.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: using uninitialized data, but this operation requires
   --> tests/fail/function_calls/arg_inplace_observe_after.rs:LL:CC
    |
 LL |             _observe = non_copy.0;
-   |             ^^^^^^^^^^^^^^^^^^^^^ using uninitialized data, but this operation requires initialized memory
+   |             ^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/function_calls/arg_inplace_observe_during.none.stderr b/src/tools/miri/tests/fail/function_calls/arg_inplace_observe_during.none.stderr
index 032bbfa8f18..0fc634bb7fc 100644
--- a/src/tools/miri/tests/fail/function_calls/arg_inplace_observe_during.none.stderr
+++ b/src/tools/miri/tests/fail/function_calls/arg_inplace_observe_during.none.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: using uninitialized data, but this operation requires
   --> tests/fail/function_calls/arg_inplace_observe_during.rs:LL:CC
    |
 LL |     unsafe { ptr.read() };
-   |              ^^^^^^^^^^ using uninitialized data, but this operation requires initialized memory
+   |              ^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/function_calls/arg_inplace_observe_during.stack.stderr b/src/tools/miri/tests/fail/function_calls/arg_inplace_observe_during.stack.stderr
index f20ec00f97b..609599ef6ca 100644
--- a/src/tools/miri/tests/fail/function_calls/arg_inplace_observe_during.stack.stderr
+++ b/src/tools/miri/tests/fail/function_calls/arg_inplace_observe_during.stack.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: not granting access to tag <TAG> because that would r
   --> tests/fail/function_calls/arg_inplace_observe_during.rs:LL:CC
    |
 LL |     unsafe { ptr.read() };
-   |              ^^^^^^^^^^ not granting access to tag <TAG> because that would remove [Unique for <TAG>] which is strongly protected
+   |              ^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/function_calls/arg_inplace_observe_during.tree.stderr b/src/tools/miri/tests/fail/function_calls/arg_inplace_observe_during.tree.stderr
index 8996c3643db..5db5a6cac4d 100644
--- a/src/tools/miri/tests/fail/function_calls/arg_inplace_observe_during.tree.stderr
+++ b/src/tools/miri/tests/fail/function_calls/arg_inplace_observe_during.tree.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: read access through <TAG> (root of the allocation) at
   --> tests/fail/function_calls/arg_inplace_observe_during.rs:LL:CC
    |
 LL |     unsafe { ptr.read() };
-   |              ^^^^^^^^^^ read access through <TAG> (root of the allocation) at ALLOC[0x0] is forbidden
+   |              ^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> (root of the allocation) is foreign to the protected tag <TAG> (i.e., it is not a child)
diff --git a/src/tools/miri/tests/fail/function_calls/check_arg_abi.stderr b/src/tools/miri/tests/fail/function_calls/check_arg_abi.stderr
index 78730182923..83d3e6d3d1e 100644
--- a/src/tools/miri/tests/fail/function_calls/check_arg_abi.stderr
+++ b/src/tools/miri/tests/fail/function_calls/check_arg_abi.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: calling a function with calling convention "C" using
   --> tests/fail/function_calls/check_arg_abi.rs:LL:CC
    |
 LL |         let _ = malloc(0);
-   |                 ^^^^^^^^^ calling a function with calling convention "C" using caller calling convention "Rust"
+   |                 ^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/function_calls/check_arg_count_abort.stderr b/src/tools/miri/tests/fail/function_calls/check_arg_count_abort.stderr
index 3c81ba4e141..739507fde0e 100644
--- a/src/tools/miri/tests/fail/function_calls/check_arg_count_abort.stderr
+++ b/src/tools/miri/tests/fail/function_calls/check_arg_count_abort.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: incorrect number of arguments for `abort`: got 1, exp
   --> tests/fail/function_calls/check_arg_count_abort.rs:LL:CC
    |
 LL |         abort(1);
-   |         ^^^^^^^^ incorrect number of arguments for `abort`: got 1, expected 0
+   |         ^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/function_calls/check_arg_count_too_few_args.stderr b/src/tools/miri/tests/fail/function_calls/check_arg_count_too_few_args.stderr
index eacd4045ae0..ad1dbb03476 100644
--- a/src/tools/miri/tests/fail/function_calls/check_arg_count_too_few_args.stderr
+++ b/src/tools/miri/tests/fail/function_calls/check_arg_count_too_few_args.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: incorrect number of arguments for `malloc`: got 0, ex
   --> tests/fail/function_calls/check_arg_count_too_few_args.rs:LL:CC
    |
 LL |         let _ = malloc();
-   |                 ^^^^^^^^ incorrect number of arguments for `malloc`: got 0, expected 1
+   |                 ^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/function_calls/check_arg_count_too_many_args.stderr b/src/tools/miri/tests/fail/function_calls/check_arg_count_too_many_args.stderr
index 42d5e98c01a..9dae9a02a16 100644
--- a/src/tools/miri/tests/fail/function_calls/check_arg_count_too_many_args.stderr
+++ b/src/tools/miri/tests/fail/function_calls/check_arg_count_too_many_args.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: incorrect number of arguments for `malloc`: got 2, ex
   --> tests/fail/function_calls/check_arg_count_too_many_args.rs:LL:CC
    |
 LL |         let _ = malloc(1, 2);
-   |                 ^^^^^^^^^^^^ incorrect number of arguments for `malloc`: got 2, expected 1
+   |                 ^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/function_calls/check_callback_abi.stderr b/src/tools/miri/tests/fail/function_calls/check_callback_abi.stderr
index 20182ac9236..cbca7e920b7 100644
--- a/src/tools/miri/tests/fail/function_calls/check_callback_abi.stderr
+++ b/src/tools/miri/tests/fail/function_calls/check_callback_abi.stderr
@@ -7,7 +7,7 @@ LL | |             std::mem::transmute::<extern "C" fn(*mut u8), _>(try_fn),
 LL | |             std::ptr::null_mut(),
 LL | |             |_, _| unreachable!(),
 LL | |         );
-   | |_________^ calling a function with calling convention "C" using calling convention "Rust"
+   | |_________^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/function_calls/exported_symbol_abi_mismatch.cache.stderr b/src/tools/miri/tests/fail/function_calls/exported_symbol_abi_mismatch.cache.stderr
index 46a32d1487e..6a8f444b37c 100644
--- a/src/tools/miri/tests/fail/function_calls/exported_symbol_abi_mismatch.cache.stderr
+++ b/src/tools/miri/tests/fail/function_calls/exported_symbol_abi_mismatch.cache.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: calling a function with calling convention "Rust" usi
   --> tests/fail/function_calls/exported_symbol_abi_mismatch.rs:LL:CC
    |
 LL |             foo();
-   |             ^^^^^ calling a function with calling convention "Rust" using calling convention "C"
+   |             ^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/function_calls/exported_symbol_abi_mismatch.fn_ptr.stderr b/src/tools/miri/tests/fail/function_calls/exported_symbol_abi_mismatch.fn_ptr.stderr
index 38725289919..07bd5e0effc 100644
--- a/src/tools/miri/tests/fail/function_calls/exported_symbol_abi_mismatch.fn_ptr.stderr
+++ b/src/tools/miri/tests/fail/function_calls/exported_symbol_abi_mismatch.fn_ptr.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: calling a function with calling convention "Rust" usi
   --> tests/fail/function_calls/exported_symbol_abi_mismatch.rs:LL:CC
    |
 LL |         std::mem::transmute::<unsafe fn(), unsafe extern "C" fn()>(foo)();
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ calling a function with calling convention "Rust" using calling convention "C"
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/function_calls/exported_symbol_abi_mismatch.no_cache.stderr b/src/tools/miri/tests/fail/function_calls/exported_symbol_abi_mismatch.no_cache.stderr
index 46a32d1487e..6a8f444b37c 100644
--- a/src/tools/miri/tests/fail/function_calls/exported_symbol_abi_mismatch.no_cache.stderr
+++ b/src/tools/miri/tests/fail/function_calls/exported_symbol_abi_mismatch.no_cache.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: calling a function with calling convention "Rust" usi
   --> tests/fail/function_calls/exported_symbol_abi_mismatch.rs:LL:CC
    |
 LL |             foo();
-   |             ^^^^^ calling a function with calling convention "Rust" using calling convention "C"
+   |             ^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/function_calls/exported_symbol_bad_unwind1.stderr b/src/tools/miri/tests/fail/function_calls/exported_symbol_bad_unwind1.stderr
index 8e63d78d759..9e6abf219f1 100644
--- a/src/tools/miri/tests/fail/function_calls/exported_symbol_bad_unwind1.stderr
+++ b/src/tools/miri/tests/fail/function_calls/exported_symbol_bad_unwind1.stderr
@@ -7,7 +7,7 @@ error: Undefined Behavior: unwinding past a stack frame that does not allow unwi
   --> tests/fail/function_calls/exported_symbol_bad_unwind1.rs:LL:CC
    |
 LL |     unsafe { unwind() }
-   |              ^^^^^^^^ unwinding past a stack frame that does not allow unwinding
+   |              ^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/function_calls/exported_symbol_bad_unwind2.both.stderr b/src/tools/miri/tests/fail/function_calls/exported_symbol_bad_unwind2.both.stderr
index 7cb2bf99678..deec81f7e51 100644
--- a/src/tools/miri/tests/fail/function_calls/exported_symbol_bad_unwind2.both.stderr
+++ b/src/tools/miri/tests/fail/function_calls/exported_symbol_bad_unwind2.both.stderr
@@ -12,7 +12,7 @@ error: abnormal termination: the program aborted execution
   --> RUSTLIB/std/src/sys/pal/PLATFORM/mod.rs:LL:CC
    |
 LL | ABORT()
-   | ^ the program aborted execution
+   | ^ abnormal termination occurred here
    |
    = note: BACKTRACE:
    = note: inside `std::sys::pal::PLATFORM::abort_internal` at RUSTLIB/std/src/sys/pal/PLATFORM/mod.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/function_calls/exported_symbol_bad_unwind2.definition.stderr b/src/tools/miri/tests/fail/function_calls/exported_symbol_bad_unwind2.definition.stderr
index 7cb2bf99678..deec81f7e51 100644
--- a/src/tools/miri/tests/fail/function_calls/exported_symbol_bad_unwind2.definition.stderr
+++ b/src/tools/miri/tests/fail/function_calls/exported_symbol_bad_unwind2.definition.stderr
@@ -12,7 +12,7 @@ error: abnormal termination: the program aborted execution
   --> RUSTLIB/std/src/sys/pal/PLATFORM/mod.rs:LL:CC
    |
 LL | ABORT()
-   | ^ the program aborted execution
+   | ^ abnormal termination occurred here
    |
    = note: BACKTRACE:
    = note: inside `std::sys::pal::PLATFORM::abort_internal` at RUSTLIB/std/src/sys/pal/PLATFORM/mod.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/function_calls/exported_symbol_bad_unwind2.extern_block.stderr b/src/tools/miri/tests/fail/function_calls/exported_symbol_bad_unwind2.extern_block.stderr
index 767fd929fd4..5a3d5b4a5eb 100644
--- a/src/tools/miri/tests/fail/function_calls/exported_symbol_bad_unwind2.extern_block.stderr
+++ b/src/tools/miri/tests/fail/function_calls/exported_symbol_bad_unwind2.extern_block.stderr
@@ -7,7 +7,7 @@ error: Undefined Behavior: unwinding past a stack frame that does not allow unwi
   --> tests/fail/function_calls/exported_symbol_bad_unwind2.rs:LL:CC
    |
 LL |     unsafe { nounwind() }
-   | ^ unwinding past a stack frame that does not allow unwinding
+   | ^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/function_calls/exported_symbol_clashing.stderr b/src/tools/miri/tests/fail/function_calls/exported_symbol_clashing.stderr
index e9e580ffc86..50ca5c611de 100644
--- a/src/tools/miri/tests/fail/function_calls/exported_symbol_clashing.stderr
+++ b/src/tools/miri/tests/fail/function_calls/exported_symbol_clashing.stderr
@@ -2,7 +2,7 @@ error: multiple definitions of symbol `foo`
   --> tests/fail/function_calls/exported_symbol_clashing.rs:LL:CC
    |
 LL |     unsafe { foo() }
-   |              ^^^^^ multiple definitions of symbol `foo`
+   |              ^^^^^ error occurred here
    |
 help: it's first defined here, in crate `exported_symbol_clashing`
   --> tests/fail/function_calls/exported_symbol_clashing.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/function_calls/exported_symbol_shim_clashing.stderr b/src/tools/miri/tests/fail/function_calls/exported_symbol_shim_clashing.stderr
index fb9cc47c7a8..ea3b73f8724 100644
--- a/src/tools/miri/tests/fail/function_calls/exported_symbol_shim_clashing.stderr
+++ b/src/tools/miri/tests/fail/function_calls/exported_symbol_shim_clashing.stderr
@@ -2,7 +2,7 @@ error: found `malloc` symbol definition that clashes with a built-in shim
   --> tests/fail/function_calls/exported_symbol_shim_clashing.rs:LL:CC
    |
 LL |         malloc(0);
-   |         ^^^^^^^^^ found `malloc` symbol definition that clashes with a built-in shim
+   |         ^^^^^^^^^ error occurred here
    |
 help: the `malloc` symbol is defined here
   --> tests/fail/function_calls/exported_symbol_shim_clashing.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/function_calls/exported_symbol_wrong_arguments.stderr b/src/tools/miri/tests/fail/function_calls/exported_symbol_wrong_arguments.stderr
index 1ff9aa36f1e..6699e5fea13 100644
--- a/src/tools/miri/tests/fail/function_calls/exported_symbol_wrong_arguments.stderr
+++ b/src/tools/miri/tests/fail/function_calls/exported_symbol_wrong_arguments.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: calling a function with more arguments than it expect
   --> tests/fail/function_calls/exported_symbol_wrong_arguments.rs:LL:CC
    |
 LL |     unsafe { foo(1) }
-   |              ^^^^^^ calling a function with more arguments than it expected
+   |              ^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/function_calls/exported_symbol_wrong_type.stderr b/src/tools/miri/tests/fail/function_calls/exported_symbol_wrong_type.stderr
index 29c87e8c437..7a4f3f17f6f 100644
--- a/src/tools/miri/tests/fail/function_calls/exported_symbol_wrong_type.stderr
+++ b/src/tools/miri/tests/fail/function_calls/exported_symbol_wrong_type.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: attempt to call an exported symbol that is not define
   --> tests/fail/function_calls/exported_symbol_wrong_type.rs:LL:CC
    |
 LL |     unsafe { FOO() }
-   |              ^^^^^ attempt to call an exported symbol that is not defined as a function
+   |              ^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/function_calls/return_pointer_aliasing_read.none.stderr b/src/tools/miri/tests/fail/function_calls/return_pointer_aliasing_read.none.stderr
index 9da2c3589da..746ab2e59ca 100644
--- a/src/tools/miri/tests/fail/function_calls/return_pointer_aliasing_read.none.stderr
+++ b/src/tools/miri/tests/fail/function_calls/return_pointer_aliasing_read.none.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: using uninitialized data, but this operation requires
   --> tests/fail/function_calls/return_pointer_aliasing_read.rs:LL:CC
    |
 LL |     unsafe { ptr.read() };
-   |              ^^^^^^^^^^ using uninitialized data, but this operation requires initialized memory
+   |              ^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/function_calls/return_pointer_aliasing_read.stack.stderr b/src/tools/miri/tests/fail/function_calls/return_pointer_aliasing_read.stack.stderr
index 47e5ee48292..77cc0332a1c 100644
--- a/src/tools/miri/tests/fail/function_calls/return_pointer_aliasing_read.stack.stderr
+++ b/src/tools/miri/tests/fail/function_calls/return_pointer_aliasing_read.stack.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: not granting access to tag <TAG> because that would r
   --> tests/fail/function_calls/return_pointer_aliasing_read.rs:LL:CC
    |
 LL |     unsafe { ptr.read() };
-   |              ^^^^^^^^^^ not granting access to tag <TAG> because that would remove [Unique for <TAG>] which is strongly protected
+   |              ^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/function_calls/return_pointer_aliasing_read.tree.stderr b/src/tools/miri/tests/fail/function_calls/return_pointer_aliasing_read.tree.stderr
index 7eb237ca1a7..bae3819c979 100644
--- a/src/tools/miri/tests/fail/function_calls/return_pointer_aliasing_read.tree.stderr
+++ b/src/tools/miri/tests/fail/function_calls/return_pointer_aliasing_read.tree.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: read access through <TAG> (root of the allocation) at
   --> tests/fail/function_calls/return_pointer_aliasing_read.rs:LL:CC
    |
 LL |     unsafe { ptr.read() };
-   |              ^^^^^^^^^^ read access through <TAG> (root of the allocation) at ALLOC[0x0] is forbidden
+   |              ^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> (root of the allocation) is foreign to the protected tag <TAG> (i.e., it is not a child)
diff --git a/src/tools/miri/tests/fail/function_calls/return_pointer_aliasing_write.stack.stderr b/src/tools/miri/tests/fail/function_calls/return_pointer_aliasing_write.stack.stderr
index 813042f06a6..828b2339f8c 100644
--- a/src/tools/miri/tests/fail/function_calls/return_pointer_aliasing_write.stack.stderr
+++ b/src/tools/miri/tests/fail/function_calls/return_pointer_aliasing_write.stack.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: not granting access to tag <TAG> because that would r
   --> tests/fail/function_calls/return_pointer_aliasing_write.rs:LL:CC
    |
 LL |     unsafe { ptr.write(0) };
-   |              ^^^^^^^^^^^^ not granting access to tag <TAG> because that would remove [Unique for <TAG>] which is strongly protected
+   |              ^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/function_calls/return_pointer_aliasing_write.tree.stderr b/src/tools/miri/tests/fail/function_calls/return_pointer_aliasing_write.tree.stderr
index 5090ec06b78..e0df9370fee 100644
--- a/src/tools/miri/tests/fail/function_calls/return_pointer_aliasing_write.tree.stderr
+++ b/src/tools/miri/tests/fail/function_calls/return_pointer_aliasing_write.tree.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: write access through <TAG> (root of the allocation) a
   --> tests/fail/function_calls/return_pointer_aliasing_write.rs:LL:CC
    |
 LL |     unsafe { ptr.write(0) };
-   |              ^^^^^^^^^^^^ write access through <TAG> (root of the allocation) at ALLOC[0x0] is forbidden
+   |              ^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> (root of the allocation) is foreign to the protected tag <TAG> (i.e., it is not a child)
diff --git a/src/tools/miri/tests/fail/function_calls/return_pointer_aliasing_write_tail_call.stack.stderr b/src/tools/miri/tests/fail/function_calls/return_pointer_aliasing_write_tail_call.stack.stderr
index a6a0362a226..f5183cfaf5b 100644
--- a/src/tools/miri/tests/fail/function_calls/return_pointer_aliasing_write_tail_call.stack.stderr
+++ b/src/tools/miri/tests/fail/function_calls/return_pointer_aliasing_write_tail_call.stack.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: not granting access to tag <TAG> because that would r
   --> tests/fail/function_calls/return_pointer_aliasing_write_tail_call.rs:LL:CC
    |
 LL |     unsafe { ptr.write(0) };
-   |              ^^^^^^^^^^^^ not granting access to tag <TAG> because that would remove [Unique for <TAG>] which is strongly protected
+   |              ^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/function_calls/return_pointer_aliasing_write_tail_call.tree.stderr b/src/tools/miri/tests/fail/function_calls/return_pointer_aliasing_write_tail_call.tree.stderr
index 26a54fe8748..fa03ed6869b 100644
--- a/src/tools/miri/tests/fail/function_calls/return_pointer_aliasing_write_tail_call.tree.stderr
+++ b/src/tools/miri/tests/fail/function_calls/return_pointer_aliasing_write_tail_call.tree.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: write access through <TAG> (root of the allocation) a
   --> tests/fail/function_calls/return_pointer_aliasing_write_tail_call.rs:LL:CC
    |
 LL |     unsafe { ptr.write(0) };
-   |              ^^^^^^^^^^^^ write access through <TAG> (root of the allocation) at ALLOC[0x0] is forbidden
+   |              ^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> (root of the allocation) is foreign to the protected tag <TAG> (i.e., it is not a child)
diff --git a/src/tools/miri/tests/fail/function_calls/return_pointer_on_unwind.stderr b/src/tools/miri/tests/fail/function_calls/return_pointer_on_unwind.stderr
index e2a3d1600ea..7747a75d1cf 100644
--- a/src/tools/miri/tests/fail/function_calls/return_pointer_on_unwind.stderr
+++ b/src/tools/miri/tests/fail/function_calls/return_pointer_on_unwind.stderr
@@ -7,7 +7,7 @@ error: Undefined Behavior: using uninitialized data, but this operation requires
   --> tests/fail/function_calls/return_pointer_on_unwind.rs:LL:CC
    |
 LL |     dbg!(x.0);
-   |     ^^^^^^^^^ using uninitialized data, but this operation requires initialized memory
+   |     ^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/function_calls/simd_feature_flag_difference.stderr b/src/tools/miri/tests/fail/function_calls/simd_feature_flag_difference.stderr
index 1d5b331be6c..755bc3e7c2c 100644
--- a/src/tools/miri/tests/fail/function_calls/simd_feature_flag_difference.stderr
+++ b/src/tools/miri/tests/fail/function_calls/simd_feature_flag_difference.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: calling a function that requires unavailable target f
   --> tests/fail/function_calls/simd_feature_flag_difference.rs:LL:CC
    |
 LL |     unsafe { foo(0.0, x) }
-   |              ^^^^^^^^^^^ calling a function that requires unavailable target features: avx
+   |              ^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/function_calls/target_feature.stderr b/src/tools/miri/tests/fail/function_calls/target_feature.stderr
index 937bd4a5951..e80e2234663 100644
--- a/src/tools/miri/tests/fail/function_calls/target_feature.stderr
+++ b/src/tools/miri/tests/fail/function_calls/target_feature.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: calling a function that requires unavailable target f
   --> tests/fail/function_calls/target_feature.rs:LL:CC
    |
 LL |         ssse3_fn();
-   |         ^^^^^^^^^^ calling a function that requires unavailable target features: ssse3
+   |         ^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/function_calls/target_feature_wasm.stderr b/src/tools/miri/tests/fail/function_calls/target_feature_wasm.stderr
index 9cc81546531..a89c5912345 100644
--- a/src/tools/miri/tests/fail/function_calls/target_feature_wasm.stderr
+++ b/src/tools/miri/tests/fail/function_calls/target_feature_wasm.stderr
@@ -2,7 +2,7 @@ error: abnormal termination: calling a function that requires unavailable target
   --> tests/fail/function_calls/target_feature_wasm.rs:LL:CC
    |
 LL |     simd128_fn();
-   |     ^^^^^^^^^^^^ calling a function that requires unavailable target features: simd128
+   |     ^^^^^^^^^^^^ abnormal termination occurred here
    |
    = note: BACKTRACE:
    = note: inside `main` at tests/fail/function_calls/target_feature_wasm.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/function_pointers/abi_mismatch_array_vs_struct.stderr b/src/tools/miri/tests/fail/function_pointers/abi_mismatch_array_vs_struct.stderr
index 521cececc37..cabefa8bee9 100644
--- a/src/tools/miri/tests/fail/function_pointers/abi_mismatch_array_vs_struct.stderr
+++ b/src/tools/miri/tests/fail/function_pointers/abi_mismatch_array_vs_struct.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: calling a function with argument of type S passing da
   --> tests/fail/function_pointers/abi_mismatch_array_vs_struct.rs:LL:CC
    |
 LL |     g(Default::default())
-   |     ^^^^^^^^^^^^^^^^^^^^^ calling a function with argument of type S passing data of type [i32; 4]
+   |     ^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/function_pointers/abi_mismatch_int_vs_float.stderr b/src/tools/miri/tests/fail/function_pointers/abi_mismatch_int_vs_float.stderr
index 20704299257..52cc48d58ce 100644
--- a/src/tools/miri/tests/fail/function_pointers/abi_mismatch_int_vs_float.stderr
+++ b/src/tools/miri/tests/fail/function_pointers/abi_mismatch_int_vs_float.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: calling a function with argument of type f32 passing
   --> tests/fail/function_pointers/abi_mismatch_int_vs_float.rs:LL:CC
    |
 LL |     g(42)
-   |     ^^^^^ calling a function with argument of type f32 passing data of type i32
+   |     ^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/function_pointers/abi_mismatch_raw_pointer.stderr b/src/tools/miri/tests/fail/function_pointers/abi_mismatch_raw_pointer.stderr
index 3e3d07e1484..2fbb0408c59 100644
--- a/src/tools/miri/tests/fail/function_pointers/abi_mismatch_raw_pointer.stderr
+++ b/src/tools/miri/tests/fail/function_pointers/abi_mismatch_raw_pointer.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: calling a function with argument of type *const [i32]
   --> tests/fail/function_pointers/abi_mismatch_raw_pointer.rs:LL:CC
    |
 LL |     g(&42 as *const i32)
-   |     ^^^^^^^^^^^^^^^^^^^^ calling a function with argument of type *const [i32] passing data of type *const i32
+   |     ^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/function_pointers/abi_mismatch_repr_C.stderr b/src/tools/miri/tests/fail/function_pointers/abi_mismatch_repr_C.stderr
index 6b92824494a..2c1ac0ee702 100644
--- a/src/tools/miri/tests/fail/function_pointers/abi_mismatch_repr_C.stderr
+++ b/src/tools/miri/tests/fail/function_pointers/abi_mismatch_repr_C.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: calling a function with argument of type S2 passing d
   --> tests/fail/function_pointers/abi_mismatch_repr_C.rs:LL:CC
    |
 LL |     fnptr(S1(NonZero::new(1).unwrap()));
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ calling a function with argument of type S2 passing data of type S1
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/function_pointers/abi_mismatch_return_type.stderr b/src/tools/miri/tests/fail/function_pointers/abi_mismatch_return_type.stderr
index 51539b078ae..28c676ad482 100644
--- a/src/tools/miri/tests/fail/function_pointers/abi_mismatch_return_type.stderr
+++ b/src/tools/miri/tests/fail/function_pointers/abi_mismatch_return_type.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: calling a function with return type u32 passing retur
   --> tests/fail/function_pointers/abi_mismatch_return_type.rs:LL:CC
    |
 LL |     g()
-   |     ^^^ calling a function with return type u32 passing return place of type ()
+   |     ^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/function_pointers/abi_mismatch_simple.stderr b/src/tools/miri/tests/fail/function_pointers/abi_mismatch_simple.stderr
index 16a83b8e342..e45ad12ec05 100644
--- a/src/tools/miri/tests/fail/function_pointers/abi_mismatch_simple.stderr
+++ b/src/tools/miri/tests/fail/function_pointers/abi_mismatch_simple.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: calling a function with argument of type (i32, i32) p
   --> tests/fail/function_pointers/abi_mismatch_simple.rs:LL:CC
    |
 LL |     g(42)
-   |     ^^^^^ calling a function with argument of type (i32, i32) passing data of type i32
+   |     ^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/function_pointers/abi_mismatch_too_few_args.stderr b/src/tools/miri/tests/fail/function_pointers/abi_mismatch_too_few_args.stderr
index 760826805c7..a03e596bba1 100644
--- a/src/tools/miri/tests/fail/function_pointers/abi_mismatch_too_few_args.stderr
+++ b/src/tools/miri/tests/fail/function_pointers/abi_mismatch_too_few_args.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: calling a function with fewer arguments than it requi
   --> tests/fail/function_pointers/abi_mismatch_too_few_args.rs:LL:CC
    |
 LL |     g()
-   |     ^^^ calling a function with fewer arguments than it requires
+   |     ^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/function_pointers/abi_mismatch_too_many_args.stderr b/src/tools/miri/tests/fail/function_pointers/abi_mismatch_too_many_args.stderr
index 9552250546b..eb681a10e43 100644
--- a/src/tools/miri/tests/fail/function_pointers/abi_mismatch_too_many_args.stderr
+++ b/src/tools/miri/tests/fail/function_pointers/abi_mismatch_too_many_args.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: calling a function with more arguments than it expect
   --> tests/fail/function_pointers/abi_mismatch_too_many_args.rs:LL:CC
    |
 LL |     g(42)
-   |     ^^^^^ calling a function with more arguments than it expected
+   |     ^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/function_pointers/abi_mismatch_vector.stderr b/src/tools/miri/tests/fail/function_pointers/abi_mismatch_vector.stderr
index 021be890d25..bad2495cb39 100644
--- a/src/tools/miri/tests/fail/function_pointers/abi_mismatch_vector.stderr
+++ b/src/tools/miri/tests/fail/function_pointers/abi_mismatch_vector.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: calling a function with argument of type std::simd::S
   --> tests/fail/function_pointers/abi_mismatch_vector.rs:LL:CC
    |
 LL |     g(Default::default())
-   |     ^^^^^^^^^^^^^^^^^^^^^ calling a function with argument of type std::simd::Simd<u32, 8> passing data of type std::simd::Simd<u64, 4>
+   |     ^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/function_pointers/cast_box_int_to_fn_ptr.stderr b/src/tools/miri/tests/fail/function_pointers/cast_box_int_to_fn_ptr.stderr
index 6112e92c939..6330f17b2b2 100644
--- a/src/tools/miri/tests/fail/function_pointers/cast_box_int_to_fn_ptr.stderr
+++ b/src/tools/miri/tests/fail/function_pointers/cast_box_int_to_fn_ptr.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: using ALLOC as function pointer but it does not point
   --> tests/fail/function_pointers/cast_box_int_to_fn_ptr.rs:LL:CC
    |
 LL |     (*g)(42)
-   |     ^^^^^^^^ using ALLOC as function pointer but it does not point to a function
+   |     ^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/function_pointers/cast_int_to_fn_ptr.stderr b/src/tools/miri/tests/fail/function_pointers/cast_int_to_fn_ptr.stderr
index 37d3beefcd7..de4c037a8b1 100644
--- a/src/tools/miri/tests/fail/function_pointers/cast_int_to_fn_ptr.stderr
+++ b/src/tools/miri/tests/fail/function_pointers/cast_int_to_fn_ptr.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: pointer not dereferenceable: pointer must point to so
   --> tests/fail/function_pointers/cast_int_to_fn_ptr.rs:LL:CC
    |
 LL |     g(42)
-   |     ^^^^^ pointer not dereferenceable: pointer must point to some allocation, but got 0x2a[noalloc] which is a dangling pointer (it has no provenance)
+   |     ^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/function_pointers/deref_fn_ptr.stderr b/src/tools/miri/tests/fail/function_pointers/deref_fn_ptr.stderr
index f7cc82b80df..c9144aa5298 100644
--- a/src/tools/miri/tests/fail/function_pointers/deref_fn_ptr.stderr
+++ b/src/tools/miri/tests/fail/function_pointers/deref_fn_ptr.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: accessing ALLOC which contains a function
   --> tests/fail/function_pointers/deref_fn_ptr.rs:LL:CC
    |
 LL |         *std::mem::transmute::<fn(), *const u8>(f)
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ accessing ALLOC which contains a function
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/function_pointers/execute_memory.stderr b/src/tools/miri/tests/fail/function_pointers/execute_memory.stderr
index e0573184282..52d03ae1733 100644
--- a/src/tools/miri/tests/fail/function_pointers/execute_memory.stderr
+++ b/src/tools/miri/tests/fail/function_pointers/execute_memory.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: using ALLOC as function pointer but it does not point
   --> tests/fail/function_pointers/execute_memory.rs:LL:CC
    |
 LL |         f()
-   |         ^^^ using ALLOC as function pointer but it does not point to a function
+   |         ^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/function_pointers/fn_ptr_offset.stderr b/src/tools/miri/tests/fail/function_pointers/fn_ptr_offset.stderr
index 4ed09683c63..f558251bea3 100644
--- a/src/tools/miri/tests/fail/function_pointers/fn_ptr_offset.stderr
+++ b/src/tools/miri/tests/fail/function_pointers/fn_ptr_offset.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: using ALLOC+0x1 as function pointer but it does not p
   --> tests/fail/function_pointers/fn_ptr_offset.rs:LL:CC
    |
 LL |     x();
-   |     ^^^ using ALLOC+0x1 as function pointer but it does not point to a function
+   |     ^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsic_fallback_is_spec.stderr b/src/tools/miri/tests/fail/intrinsic_fallback_is_spec.stderr
index a36b0fca802..a115aa2d5b5 100644
--- a/src/tools/miri/tests/fail/intrinsic_fallback_is_spec.stderr
+++ b/src/tools/miri/tests/fail/intrinsic_fallback_is_spec.stderr
@@ -2,7 +2,7 @@ error: unsupported operation: Miri can only use intrinsic fallback bodies that e
   --> tests/fail/intrinsic_fallback_is_spec.rs:LL:CC
    |
 LL |     ptr_guaranteed_cmp::<()>(std::ptr::null(), std::ptr::null());
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Miri can only use intrinsic fallback bodies that exactly reflect the specification: they fully check for UB and are as non-deterministic as possible. After verifying that `ptr_guaranteed_cmp` does so, add the `#[miri::intrinsic_fallback_is_spec]` attribute to it; also ping @rust-lang/miri when you do that
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ unsupported operation occurred here
    |
    = help: this is likely not a bug in the program; it indicates that the program performed an operation that Miri does not support
    = note: BACKTRACE:
diff --git a/src/tools/miri/tests/fail/intrinsics/assume.stderr b/src/tools/miri/tests/fail/intrinsics/assume.stderr
index eadbd2c0d58..3e7ad34f54e 100644
--- a/src/tools/miri/tests/fail/intrinsics/assume.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/assume.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `assume` called with `false`
   --> tests/fail/intrinsics/assume.rs:LL:CC
    |
 LL |         std::intrinsics::assume(x > 42);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `assume` called with `false`
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/copy_overflow.stderr b/src/tools/miri/tests/fail/intrinsics/copy_overflow.stderr
index c50c7c1ef43..486b00c4d23 100644
--- a/src/tools/miri/tests/fail/intrinsics/copy_overflow.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/copy_overflow.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: overflow computing total size of `copy`
   --> tests/fail/intrinsics/copy_overflow.rs:LL:CC
    |
 LL |         (&mut y as *mut i32).copy_from(&x, 1usize << (mem::size_of::<usize>() * 8 - 1));
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ overflow computing total size of `copy`
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/copy_overlapping.stderr b/src/tools/miri/tests/fail/intrinsics/copy_overlapping.stderr
index 9b60a48703b..aee22698fd1 100644
--- a/src/tools/miri/tests/fail/intrinsics/copy_overlapping.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/copy_overlapping.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `copy_nonoverlapping` called on overlapping ranges
   --> tests/fail/intrinsics/copy_overlapping.rs:LL:CC
    |
 LL |         std::intrinsics::copy_nonoverlapping(a, b, 2);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `copy_nonoverlapping` called on overlapping ranges
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/copy_unaligned.stderr b/src/tools/miri/tests/fail/intrinsics/copy_unaligned.stderr
index 65dbdb3bbb6..f561e502b51 100644
--- a/src/tools/miri/tests/fail/intrinsics/copy_unaligned.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/copy_unaligned.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: accessing memory with alignment ALIGN, but alignment
   --> tests/fail/intrinsics/copy_unaligned.rs:LL:CC
    |
 LL |         std::intrinsics::copy_nonoverlapping(&data[5], ptr, 0);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ accessing memory with alignment ALIGN, but alignment ALIGN is required
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/ctlz_nonzero.stderr b/src/tools/miri/tests/fail/intrinsics/ctlz_nonzero.stderr
index 5ad3b8ad2a8..2f766ba7743 100644
--- a/src/tools/miri/tests/fail/intrinsics/ctlz_nonzero.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/ctlz_nonzero.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `ctlz_nonzero` called on 0
   --> tests/fail/intrinsics/ctlz_nonzero.rs:LL:CC
    |
 LL |         ctlz_nonzero(0u8);
-   |         ^^^^^^^^^^^^^^^^^ `ctlz_nonzero` called on 0
+   |         ^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/cttz_nonzero.stderr b/src/tools/miri/tests/fail/intrinsics/cttz_nonzero.stderr
index d0263ac1e45..66d0bac7302 100644
--- a/src/tools/miri/tests/fail/intrinsics/cttz_nonzero.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/cttz_nonzero.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `cttz_nonzero` called on 0
   --> tests/fail/intrinsics/cttz_nonzero.rs:LL:CC
    |
 LL |         cttz_nonzero(0u8);
-   |         ^^^^^^^^^^^^^^^^^ `cttz_nonzero` called on 0
+   |         ^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/disjoint_bitor.stderr b/src/tools/miri/tests/fail/intrinsics/disjoint_bitor.stderr
index 82502953118..80b27adfca8 100644
--- a/src/tools/miri/tests/fail/intrinsics/disjoint_bitor.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/disjoint_bitor.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `assume` called with `false`
   --> tests/fail/intrinsics/disjoint_bitor.rs:LL:CC
    |
 LL |     unsafe { std::intrinsics::disjoint_bitor(0b01101001_u8, 0b10001110) };
-   |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `assume` called with `false`
+   |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/div-by-zero.stderr b/src/tools/miri/tests/fail/intrinsics/div-by-zero.stderr
index e276874ba25..ec83f4a96e9 100644
--- a/src/tools/miri/tests/fail/intrinsics/div-by-zero.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/div-by-zero.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: dividing by zero
   --> tests/fail/intrinsics/div-by-zero.rs:LL:CC
    |
 LL |         let _n = unchecked_div(1i64, 0);
-   |                  ^^^^^^^^^^^^^^^^^^^^^^ dividing by zero
+   |                  ^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/exact_div1.stderr b/src/tools/miri/tests/fail/intrinsics/exact_div1.stderr
index f133baecfa2..c05dee7f6f5 100644
--- a/src/tools/miri/tests/fail/intrinsics/exact_div1.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/exact_div1.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: calculating the remainder with a divisor of zero
   --> tests/fail/intrinsics/exact_div1.rs:LL:CC
    |
 LL |     unsafe { std::intrinsics::exact_div(2, 0) };
-   |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ calculating the remainder with a divisor of zero
+   |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/exact_div2.stderr b/src/tools/miri/tests/fail/intrinsics/exact_div2.stderr
index 315417fe8df..349e30d7bfd 100644
--- a/src/tools/miri/tests/fail/intrinsics/exact_div2.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/exact_div2.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: exact_div: 2_u16 cannot be divided by 3_u16 without r
   --> tests/fail/intrinsics/exact_div2.rs:LL:CC
    |
 LL |     unsafe { std::intrinsics::exact_div(2u16, 3) };
-   |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ exact_div: 2_u16 cannot be divided by 3_u16 without remainder
+   |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/exact_div3.stderr b/src/tools/miri/tests/fail/intrinsics/exact_div3.stderr
index 42f52540a4c..e8292bbd4b4 100644
--- a/src/tools/miri/tests/fail/intrinsics/exact_div3.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/exact_div3.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: exact_div: -19_i8 cannot be divided by 2_i8 without r
   --> tests/fail/intrinsics/exact_div3.rs:LL:CC
    |
 LL |     unsafe { std::intrinsics::exact_div(-19i8, 2) };
-   |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ exact_div: -19_i8 cannot be divided by 2_i8 without remainder
+   |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/exact_div4.stderr b/src/tools/miri/tests/fail/intrinsics/exact_div4.stderr
index 723ed4e49ed..9e6ccf599a1 100644
--- a/src/tools/miri/tests/fail/intrinsics/exact_div4.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/exact_div4.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: overflow in signed remainder (dividing MIN by -1)
   --> tests/fail/intrinsics/exact_div4.rs:LL:CC
    |
 LL |     unsafe { std::intrinsics::exact_div(i64::MIN, -1) };
-   |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ overflow in signed remainder (dividing MIN by -1)
+   |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/fast_math_both.stderr b/src/tools/miri/tests/fail/intrinsics/fast_math_both.stderr
index 7579a81e3e1..c889dd01b85 100644
--- a/src/tools/miri/tests/fail/intrinsics/fast_math_both.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/fast_math_both.stderr
@@ -1,8 +1,8 @@
 error: Undefined Behavior: `fsub_fast` intrinsic called with non-finite value as both parameters
   --> tests/fail/intrinsics/fast_math_both.rs:LL:CC
    |
-LL | ...: f32 = core::intrinsics::fsub_fast(f32::NAN, f32::NAN);
-   |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `fsub_fast` intrinsic called with non-finite value as both parameters
+LL | ...   let _x: f32 = core::intrinsics::fsub_fast(f32::NAN, f32::NAN);
+   |                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/fast_math_first.stderr b/src/tools/miri/tests/fail/intrinsics/fast_math_first.stderr
index 8295ec1089f..e9c4f34ab37 100644
--- a/src/tools/miri/tests/fail/intrinsics/fast_math_first.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/fast_math_first.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `frem_fast` intrinsic called with non-finite value as
   --> tests/fail/intrinsics/fast_math_first.rs:LL:CC
    |
 LL | ...   let _x: f32 = core::intrinsics::frem_fast(f32::NAN, 3.2);
-   |                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `frem_fast` intrinsic called with non-finite value as first parameter
+   |                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/fast_math_result.stderr b/src/tools/miri/tests/fail/intrinsics/fast_math_result.stderr
index 8ddbd4cc19e..cf7198c91fd 100644
--- a/src/tools/miri/tests/fail/intrinsics/fast_math_result.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/fast_math_result.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `fdiv_fast` intrinsic produced non-finite value as re
   --> tests/fail/intrinsics/fast_math_result.rs:LL:CC
    |
 LL |         let _x: f32 = core::intrinsics::fdiv_fast(1.0, 0.0);
-   |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `fdiv_fast` intrinsic produced non-finite value as result
+   |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/fast_math_second.stderr b/src/tools/miri/tests/fail/intrinsics/fast_math_second.stderr
index 0fde006b3bd..e1323b0b515 100644
--- a/src/tools/miri/tests/fail/intrinsics/fast_math_second.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/fast_math_second.stderr
@@ -1,8 +1,8 @@
 error: Undefined Behavior: `fmul_fast` intrinsic called with non-finite value as second parameter
   --> tests/fail/intrinsics/fast_math_second.rs:LL:CC
    |
-LL | ...f32 = core::intrinsics::fmul_fast(3.4f32, f32::INFINITY);
-   |          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `fmul_fast` intrinsic called with non-finite value as second parameter
+LL | ...   let _x: f32 = core::intrinsics::fmul_fast(3.4f32, f32::INFINITY);
+   |                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/float_to_int_32_inf1.stderr b/src/tools/miri/tests/fail/intrinsics/float_to_int_32_inf1.stderr
index bcc8ff667ff..5cce3fe8592 100644
--- a/src/tools/miri/tests/fail/intrinsics/float_to_int_32_inf1.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/float_to_int_32_inf1.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `float_to_int_unchecked` intrinsic called on +Inf_f32
   --> tests/fail/intrinsics/float_to_int_32_inf1.rs:LL:CC
    |
 LL |         float_to_int_unchecked::<f32, i32>(f32::INFINITY);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `float_to_int_unchecked` intrinsic called on +Inf_f32 which cannot be represented in target type `i32`
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/float_to_int_32_infneg1.stderr b/src/tools/miri/tests/fail/intrinsics/float_to_int_32_infneg1.stderr
index 9ac910c8d2f..49e804a82ae 100644
--- a/src/tools/miri/tests/fail/intrinsics/float_to_int_32_infneg1.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/float_to_int_32_infneg1.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `float_to_int_unchecked` intrinsic called on -Inf_f32
   --> tests/fail/intrinsics/float_to_int_32_infneg1.rs:LL:CC
    |
 LL |         float_to_int_unchecked::<f32, i32>(f32::NEG_INFINITY);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `float_to_int_unchecked` intrinsic called on -Inf_f32 which cannot be represented in target type `i32`
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/float_to_int_32_nan.stderr b/src/tools/miri/tests/fail/intrinsics/float_to_int_32_nan.stderr
index b377b701361..b8cb2186eff 100644
--- a/src/tools/miri/tests/fail/intrinsics/float_to_int_32_nan.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/float_to_int_32_nan.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `float_to_int_unchecked` intrinsic called on NaN_f32
   --> tests/fail/intrinsics/float_to_int_32_nan.rs:LL:CC
    |
 LL |         float_to_int_unchecked::<f32, u32>(f32::NAN);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `float_to_int_unchecked` intrinsic called on NaN_f32 which cannot be represented in target type `u32`
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/float_to_int_32_nanneg.stderr b/src/tools/miri/tests/fail/intrinsics/float_to_int_32_nanneg.stderr
index 2a0dcdfaeef..4af308057b5 100644
--- a/src/tools/miri/tests/fail/intrinsics/float_to_int_32_nanneg.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/float_to_int_32_nanneg.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `float_to_int_unchecked` intrinsic called on NaN_f32
   --> tests/fail/intrinsics/float_to_int_32_nanneg.rs:LL:CC
    |
 LL |         float_to_int_unchecked::<f32, u32>(-f32::NAN);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `float_to_int_unchecked` intrinsic called on NaN_f32 which cannot be represented in target type `u32`
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/float_to_int_32_neg.stderr b/src/tools/miri/tests/fail/intrinsics/float_to_int_32_neg.stderr
index 45be75e2f02..efdee0814b8 100644
--- a/src/tools/miri/tests/fail/intrinsics/float_to_int_32_neg.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/float_to_int_32_neg.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `float_to_int_unchecked` intrinsic called on -1f32 wh
   --> tests/fail/intrinsics/float_to_int_32_neg.rs:LL:CC
    |
 LL |         float_to_int_unchecked::<f32, u32>(-1.000000001f32);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `float_to_int_unchecked` intrinsic called on -1f32 which cannot be represented in target type `u32`
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/float_to_int_32_too_big1.stderr b/src/tools/miri/tests/fail/intrinsics/float_to_int_32_too_big1.stderr
index 8597dc0b072..e5663a8a5f4 100644
--- a/src/tools/miri/tests/fail/intrinsics/float_to_int_32_too_big1.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/float_to_int_32_too_big1.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `float_to_int_unchecked` intrinsic called on 2.147483
   --> tests/fail/intrinsics/float_to_int_32_too_big1.rs:LL:CC
    |
 LL |         float_to_int_unchecked::<f32, i32>(2147483648.0f32);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `float_to_int_unchecked` intrinsic called on 2.14748365E+9f32 which cannot be represented in target type `i32`
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/float_to_int_32_too_big2.stderr b/src/tools/miri/tests/fail/intrinsics/float_to_int_32_too_big2.stderr
index d79004e6429..2aab07cd816 100644
--- a/src/tools/miri/tests/fail/intrinsics/float_to_int_32_too_big2.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/float_to_int_32_too_big2.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `float_to_int_unchecked` intrinsic called on 4.294967
   --> tests/fail/intrinsics/float_to_int_32_too_big2.rs:LL:CC
    |
 LL |         float_to_int_unchecked::<f32, u32>((u32::MAX - 127) as f32);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `float_to_int_unchecked` intrinsic called on 4.2949673E+9f32 which cannot be represented in target type `u32`
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/float_to_int_32_too_small1.stderr b/src/tools/miri/tests/fail/intrinsics/float_to_int_32_too_small1.stderr
index 6a1d48f4807..dbd99d12c51 100644
--- a/src/tools/miri/tests/fail/intrinsics/float_to_int_32_too_small1.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/float_to_int_32_too_small1.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `float_to_int_unchecked` intrinsic called on -2.14748
   --> tests/fail/intrinsics/float_to_int_32_too_small1.rs:LL:CC
    |
 LL |         float_to_int_unchecked::<f32, i32>(-2147483904.0f32);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `float_to_int_unchecked` intrinsic called on -2.1474839E+9f32 which cannot be represented in target type `i32`
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/float_to_int_64_inf1.stderr b/src/tools/miri/tests/fail/intrinsics/float_to_int_64_inf1.stderr
index d77544cb37f..f3348d89719 100644
--- a/src/tools/miri/tests/fail/intrinsics/float_to_int_64_inf1.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/float_to_int_64_inf1.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `float_to_int_unchecked` intrinsic called on +Inf_f64
   --> tests/fail/intrinsics/float_to_int_64_inf1.rs:LL:CC
    |
 LL |         float_to_int_unchecked::<f64, u128>(f64::INFINITY);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `float_to_int_unchecked` intrinsic called on +Inf_f64 which cannot be represented in target type `u128`
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/float_to_int_64_infneg1.stderr b/src/tools/miri/tests/fail/intrinsics/float_to_int_64_infneg1.stderr
index c6f9eb41138..b568408e53d 100644
--- a/src/tools/miri/tests/fail/intrinsics/float_to_int_64_infneg1.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/float_to_int_64_infneg1.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `float_to_int_unchecked` intrinsic called on -Inf_f64
   --> tests/fail/intrinsics/float_to_int_64_infneg1.rs:LL:CC
    |
 LL |         float_to_int_unchecked::<f64, u128>(f64::NEG_INFINITY);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `float_to_int_unchecked` intrinsic called on -Inf_f64 which cannot be represented in target type `u128`
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/float_to_int_64_infneg2.stderr b/src/tools/miri/tests/fail/intrinsics/float_to_int_64_infneg2.stderr
index fc80f1679ce..5faa13409b0 100644
--- a/src/tools/miri/tests/fail/intrinsics/float_to_int_64_infneg2.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/float_to_int_64_infneg2.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `float_to_int_unchecked` intrinsic called on -Inf_f64
   --> tests/fail/intrinsics/float_to_int_64_infneg2.rs:LL:CC
    |
 LL |         float_to_int_unchecked::<f64, i128>(f64::NEG_INFINITY);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `float_to_int_unchecked` intrinsic called on -Inf_f64 which cannot be represented in target type `i128`
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/float_to_int_64_nan.stderr b/src/tools/miri/tests/fail/intrinsics/float_to_int_64_nan.stderr
index 01059ed5a73..ed0e1582802 100644
--- a/src/tools/miri/tests/fail/intrinsics/float_to_int_64_nan.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/float_to_int_64_nan.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `float_to_int_unchecked` intrinsic called on NaN_f64
   --> tests/fail/intrinsics/float_to_int_64_nan.rs:LL:CC
    |
 LL |         float_to_int_unchecked::<f64, u32>(f64::NAN);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `float_to_int_unchecked` intrinsic called on NaN_f64 which cannot be represented in target type `u32`
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/float_to_int_64_neg.stderr b/src/tools/miri/tests/fail/intrinsics/float_to_int_64_neg.stderr
index f17d502d51c..754b5d514ce 100644
--- a/src/tools/miri/tests/fail/intrinsics/float_to_int_64_neg.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/float_to_int_64_neg.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `float_to_int_unchecked` intrinsic called on -1.00000
   --> tests/fail/intrinsics/float_to_int_64_neg.rs:LL:CC
    |
 LL |         float_to_int_unchecked::<f64, u128>(-1.0000000000001f64);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `float_to_int_unchecked` intrinsic called on -1.0000000000000999f64 which cannot be represented in target type `u128`
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/float_to_int_64_too_big1.stderr b/src/tools/miri/tests/fail/intrinsics/float_to_int_64_too_big1.stderr
index 9379be3f82f..717475704f1 100644
--- a/src/tools/miri/tests/fail/intrinsics/float_to_int_64_too_big1.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/float_to_int_64_too_big1.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `float_to_int_unchecked` intrinsic called on 21474836
   --> tests/fail/intrinsics/float_to_int_64_too_big1.rs:LL:CC
    |
 LL |         float_to_int_unchecked::<f64, i32>(2147483648.0f64);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `float_to_int_unchecked` intrinsic called on 2147483648f64 which cannot be represented in target type `i32`
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/float_to_int_64_too_big2.stderr b/src/tools/miri/tests/fail/intrinsics/float_to_int_64_too_big2.stderr
index 1c0a0e0e88b..595f427b512 100644
--- a/src/tools/miri/tests/fail/intrinsics/float_to_int_64_too_big2.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/float_to_int_64_too_big2.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `float_to_int_unchecked` intrinsic called on 9.223372
   --> tests/fail/intrinsics/float_to_int_64_too_big2.rs:LL:CC
    |
 LL |         float_to_int_unchecked::<f64, i64>(9223372036854775808.0f64);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `float_to_int_unchecked` intrinsic called on 9.2233720368547758E+18f64 which cannot be represented in target type `i64`
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/float_to_int_64_too_big3.stderr b/src/tools/miri/tests/fail/intrinsics/float_to_int_64_too_big3.stderr
index 54ff73d5961..0e180869370 100644
--- a/src/tools/miri/tests/fail/intrinsics/float_to_int_64_too_big3.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/float_to_int_64_too_big3.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `float_to_int_unchecked` intrinsic called on 1.844674
   --> tests/fail/intrinsics/float_to_int_64_too_big3.rs:LL:CC
    |
 LL |         float_to_int_unchecked::<f64, u64>(18446744073709551616.0f64);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `float_to_int_unchecked` intrinsic called on 1.8446744073709552E+19f64 which cannot be represented in target type `u64`
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/float_to_int_64_too_big4.stderr b/src/tools/miri/tests/fail/intrinsics/float_to_int_64_too_big4.stderr
index b622867c097..0dd317d4b77 100644
--- a/src/tools/miri/tests/fail/intrinsics/float_to_int_64_too_big4.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/float_to_int_64_too_big4.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `float_to_int_unchecked` intrinsic called on 3.402823
   --> tests/fail/intrinsics/float_to_int_64_too_big4.rs:LL:CC
    |
 LL |         float_to_int_unchecked::<f64, u128>(u128::MAX as f64);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `float_to_int_unchecked` intrinsic called on 3.4028236692093846E+38f64 which cannot be represented in target type `u128`
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/float_to_int_64_too_big5.stderr b/src/tools/miri/tests/fail/intrinsics/float_to_int_64_too_big5.stderr
index ffb8b0d1743..ac8a2a85889 100644
--- a/src/tools/miri/tests/fail/intrinsics/float_to_int_64_too_big5.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/float_to_int_64_too_big5.stderr
@@ -1,8 +1,8 @@
 error: Undefined Behavior: `float_to_int_unchecked` intrinsic called on 2.4028236692093845E+38f64 which cannot be represented in target type `i128`
   --> tests/fail/intrinsics/float_to_int_64_too_big5.rs:LL:CC
    |
-LL |         float_to_int_unchecked::<f64, i128>(240282366920938463463374607431768211455.0f64);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `float_to_int_unchecked` intrinsic called on 2.4028236692093845E+38f64 which cannot be represented in target type `i128`
+LL | ...   float_to_int_unchecked::<f64, i128>(240282366920938463463374607431768211455.0f64);
+   |       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/float_to_int_64_too_big6.stderr b/src/tools/miri/tests/fail/intrinsics/float_to_int_64_too_big6.stderr
index 8c5d81e01c2..e6e4618c13d 100644
--- a/src/tools/miri/tests/fail/intrinsics/float_to_int_64_too_big6.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/float_to_int_64_too_big6.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `float_to_int_unchecked` intrinsic called on 1.797693
   --> tests/fail/intrinsics/float_to_int_64_too_big6.rs:LL:CC
    |
 LL |         float_to_int_unchecked::<f64, u128>(f64::MAX);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `float_to_int_unchecked` intrinsic called on 1.7976931348623157E+308f64 which cannot be represented in target type `u128`
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/float_to_int_64_too_big7.stderr b/src/tools/miri/tests/fail/intrinsics/float_to_int_64_too_big7.stderr
index 237540e2a64..b82a7f1a4c7 100644
--- a/src/tools/miri/tests/fail/intrinsics/float_to_int_64_too_big7.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/float_to_int_64_too_big7.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `float_to_int_unchecked` intrinsic called on -1.79769
   --> tests/fail/intrinsics/float_to_int_64_too_big7.rs:LL:CC
    |
 LL |         float_to_int_unchecked::<f64, i128>(f64::MIN);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `float_to_int_unchecked` intrinsic called on -1.7976931348623157E+308f64 which cannot be represented in target type `i128`
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/float_to_int_64_too_small1.stderr b/src/tools/miri/tests/fail/intrinsics/float_to_int_64_too_small1.stderr
index d1b9076d14b..37b7cae320d 100644
--- a/src/tools/miri/tests/fail/intrinsics/float_to_int_64_too_small1.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/float_to_int_64_too_small1.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `float_to_int_unchecked` intrinsic called on -2147483
   --> tests/fail/intrinsics/float_to_int_64_too_small1.rs:LL:CC
    |
 LL |         float_to_int_unchecked::<f64, i32>(-2147483649.0f64);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `float_to_int_unchecked` intrinsic called on -2147483649f64 which cannot be represented in target type `i32`
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/float_to_int_64_too_small2.stderr b/src/tools/miri/tests/fail/intrinsics/float_to_int_64_too_small2.stderr
index bc167cd0693..63050939ef9 100644
--- a/src/tools/miri/tests/fail/intrinsics/float_to_int_64_too_small2.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/float_to_int_64_too_small2.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `float_to_int_unchecked` intrinsic called on -9.22337
   --> tests/fail/intrinsics/float_to_int_64_too_small2.rs:LL:CC
    |
 LL |         float_to_int_unchecked::<f64, i64>(-9223372036854777856.0f64);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `float_to_int_unchecked` intrinsic called on -9.2233720368547778E+18f64 which cannot be represented in target type `i64`
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/float_to_int_64_too_small3.stderr b/src/tools/miri/tests/fail/intrinsics/float_to_int_64_too_small3.stderr
index 60c637b02de..c3776e221e8 100644
--- a/src/tools/miri/tests/fail/intrinsics/float_to_int_64_too_small3.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/float_to_int_64_too_small3.stderr
@@ -1,8 +1,8 @@
 error: Undefined Behavior: `float_to_int_unchecked` intrinsic called on -2.4028236692093845E+38f64 which cannot be represented in target type `i128`
   --> tests/fail/intrinsics/float_to_int_64_too_small3.rs:LL:CC
    |
-LL |         float_to_int_unchecked::<f64, i128>(-240282366920938463463374607431768211455.0f64);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `float_to_int_unchecked` intrinsic called on -2.4028236692093845E+38f64 which cannot be represented in target type `i128`
+LL | ...   float_to_int_unchecked::<f64, i128>(-240282366920938463463374607431768211455.0f64);
+   |       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/intrinsic_target_feature.stderr b/src/tools/miri/tests/fail/intrinsics/intrinsic_target_feature.stderr
index a846fc5dec3..11c3c85be9c 100644
--- a/src/tools/miri/tests/fail/intrinsics/intrinsic_target_feature.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/intrinsic_target_feature.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: attempted to call intrinsic `llvm.x86.sse41.dpps` tha
   --> tests/fail/intrinsics/intrinsic_target_feature.rs:LL:CC
    |
 LL |         dpps(_mm_setzero_ps(), _mm_setzero_ps(), 0);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ attempted to call intrinsic `llvm.x86.sse41.dpps` that requires missing target feature sse4.1
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/ptr_metadata_uninit_slice_data.stderr b/src/tools/miri/tests/fail/intrinsics/ptr_metadata_uninit_slice_data.stderr
index 16708ec275e..1c22876ba43 100644
--- a/src/tools/miri/tests/fail/intrinsics/ptr_metadata_uninit_slice_data.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/ptr_metadata_uninit_slice_data.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: using uninitialized data, but this operation requires
   --> tests/fail/intrinsics/ptr_metadata_uninit_slice_data.rs:LL:CC
    |
 LL |             RET = PtrMetadata(*p);
-   |             ^^^^^^^^^^^^^^^^^^^^^ using uninitialized data, but this operation requires initialized memory
+   |             ^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/ptr_metadata_uninit_slice_len.stderr b/src/tools/miri/tests/fail/intrinsics/ptr_metadata_uninit_slice_len.stderr
index ed7acfaa1e0..00e63b1275f 100644
--- a/src/tools/miri/tests/fail/intrinsics/ptr_metadata_uninit_slice_len.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/ptr_metadata_uninit_slice_len.stderr
@@ -16,7 +16,7 @@ error: Undefined Behavior: using uninitialized data, but this operation requires
   --> tests/fail/intrinsics/ptr_metadata_uninit_slice_len.rs:LL:CC
    |
 LL |             RET = PtrMetadata(*p);
-   |             ^^^^^^^^^^^^^^^^^^^^^ using uninitialized data, but this operation requires initialized memory
+   |             ^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/ptr_metadata_uninit_thin.stderr b/src/tools/miri/tests/fail/intrinsics/ptr_metadata_uninit_thin.stderr
index 4e0b8d9a429..24066953d79 100644
--- a/src/tools/miri/tests/fail/intrinsics/ptr_metadata_uninit_thin.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/ptr_metadata_uninit_thin.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: using uninitialized data, but this operation requires
   --> tests/fail/intrinsics/ptr_metadata_uninit_thin.rs:LL:CC
    |
 LL |             RET = PtrMetadata(*p);
-   |             ^^^^^^^^^^^^^^^^^^^^^ using uninitialized data, but this operation requires initialized memory
+   |             ^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/ptr_offset_from_different_allocs.stderr b/src/tools/miri/tests/fail/intrinsics/ptr_offset_from_different_allocs.stderr
index 34d7c6a8021..4922afc8d10 100644
--- a/src/tools/miri/tests/fail/intrinsics/ptr_offset_from_different_allocs.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/ptr_offset_from_different_allocs.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `ptr_offset_from` called on two different pointers th
   --> tests/fail/intrinsics/ptr_offset_from_different_allocs.rs:LL:CC
    |
 LL |         (&1_u8 as *const u8).offset_from(&2_u8);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `ptr_offset_from` called on two different pointers that are not both derived from the same allocation
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/ptr_offset_from_different_ints.stderr b/src/tools/miri/tests/fail/intrinsics/ptr_offset_from_different_ints.stderr
index 897945d6d5d..41567e7ec99 100644
--- a/src/tools/miri/tests/fail/intrinsics/ptr_offset_from_different_ints.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/ptr_offset_from_different_ints.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `ptr_offset_from` called on two different pointers th
   --> tests/fail/intrinsics/ptr_offset_from_different_ints.rs:LL:CC
    |
 LL |         let _ = p1.byte_offset_from(p2);
-   |                 ^^^^^^^^^^^^^^^^^^^^^^^ `ptr_offset_from` called on two different pointers that are not both derived from the same allocation
+   |                 ^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/ptr_offset_from_oob.stderr b/src/tools/miri/tests/fail/intrinsics/ptr_offset_from_oob.stderr
index 67df633bef5..f380416af69 100644
--- a/src/tools/miri/tests/fail/intrinsics/ptr_offset_from_oob.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/ptr_offset_from_oob.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `ptr_offset_from` called on two different pointers wh
   --> tests/fail/intrinsics/ptr_offset_from_oob.rs:LL:CC
    |
 LL |         ptr.wrapping_add(4).offset_from(ptr);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `ptr_offset_from` called on two different pointers where the memory range between them is not in-bounds of an allocation
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/ptr_offset_from_unsigned_neg.stderr b/src/tools/miri/tests/fail/intrinsics/ptr_offset_from_unsigned_neg.stderr
index 80e3f2c22a1..a74c697df41 100644
--- a/src/tools/miri/tests/fail/intrinsics/ptr_offset_from_unsigned_neg.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/ptr_offset_from_unsigned_neg.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `ptr_offset_from_unsigned` called when first pointer
   --> tests/fail/intrinsics/ptr_offset_from_unsigned_neg.rs:LL:CC
    |
 LL |     let _val = unsafe { ptr1.offset_from_unsigned(ptr2) };
-   |                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `ptr_offset_from_unsigned` called when first pointer has smaller address than second: $ADDR < $ADDR
+   |                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/ptr_offset_int_plus_int.stderr b/src/tools/miri/tests/fail/intrinsics/ptr_offset_int_plus_int.stderr
index b7ed36f6428..6e49617839b 100644
--- a/src/tools/miri/tests/fail/intrinsics/ptr_offset_int_plus_int.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/ptr_offset_int_plus_int.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: in-bounds pointer arithmetic failed: attempting to of
   --> tests/fail/intrinsics/ptr_offset_int_plus_int.rs:LL:CC
    |
 LL |         let _val = (1 as *mut u8).offset(1);
-   |                    ^^^^^^^^^^^^^^^^^^^^^^^^ in-bounds pointer arithmetic failed: attempting to offset pointer by 1 byte, but got 0x1[noalloc] which is a dangling pointer (it has no provenance)
+   |                    ^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/ptr_offset_int_plus_ptr.stderr b/src/tools/miri/tests/fail/intrinsics/ptr_offset_int_plus_ptr.stderr
index 29d9e1c64bd..ace3d61499f 100644
--- a/src/tools/miri/tests/fail/intrinsics/ptr_offset_int_plus_ptr.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/ptr_offset_int_plus_ptr.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: in-bounds pointer arithmetic failed: attempting to of
   --> tests/fail/intrinsics/ptr_offset_int_plus_ptr.rs:LL:CC
    |
 LL |         let _val = (1 as *mut u8).offset(ptr as isize);
-   |                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ in-bounds pointer arithmetic failed: attempting to offset pointer by $BYTES bytes, but got 0x1[noalloc] which is a dangling pointer (it has no provenance)
+   |                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/ptr_offset_out_of_bounds.stderr b/src/tools/miri/tests/fail/intrinsics/ptr_offset_out_of_bounds.stderr
index 143fae8587b..b2039a792e9 100644
--- a/src/tools/miri/tests/fail/intrinsics/ptr_offset_out_of_bounds.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/ptr_offset_out_of_bounds.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: in-bounds pointer arithmetic failed: attempting to of
   --> tests/fail/intrinsics/ptr_offset_out_of_bounds.rs:LL:CC
    |
 LL |     let x = unsafe { x.offset(5) };
-   |                      ^^^^^^^^^^^ in-bounds pointer arithmetic failed: attempting to offset pointer by 5 bytes, but got ALLOC which is only 4 bytes from the end of the allocation
+   |                      ^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/ptr_offset_out_of_bounds_neg.stderr b/src/tools/miri/tests/fail/intrinsics/ptr_offset_out_of_bounds_neg.stderr
index 14163d92404..f2e6f2b9e26 100644
--- a/src/tools/miri/tests/fail/intrinsics/ptr_offset_out_of_bounds_neg.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/ptr_offset_out_of_bounds_neg.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: in-bounds pointer arithmetic failed: attempting to of
   --> tests/fail/intrinsics/ptr_offset_out_of_bounds_neg.rs:LL:CC
    |
 LL |     let x = unsafe { x.offset(-1) };
-   |                      ^^^^^^^^^^^^ in-bounds pointer arithmetic failed: attempting to offset pointer by -1 bytes, but got ALLOC which is at the beginning of the allocation
+   |                      ^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/ptr_offset_overflow.stderr b/src/tools/miri/tests/fail/intrinsics/ptr_offset_overflow.stderr
index af08bfb3c94..741dd91b355 100644
--- a/src/tools/miri/tests/fail/intrinsics/ptr_offset_overflow.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/ptr_offset_overflow.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: in-bounds pointer arithmetic failed: attempting to of
   --> tests/fail/intrinsics/ptr_offset_overflow.rs:LL:CC
    |
 LL |     let x = unsafe { x.offset(isize::MIN) };
-   |                      ^^^^^^^^^^^^^^^^^^^^ in-bounds pointer arithmetic failed: attempting to offset pointer by -$BYTES bytes, but got ALLOC which is at the beginning of the allocation
+   |                      ^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/ptr_offset_unsigned_overflow.stderr b/src/tools/miri/tests/fail/intrinsics/ptr_offset_unsigned_overflow.stderr
index e03bdfdb85d..eb00c369f99 100644
--- a/src/tools/miri/tests/fail/intrinsics/ptr_offset_unsigned_overflow.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/ptr_offset_unsigned_overflow.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: overflowing pointer arithmetic: the total offset in b
   --> tests/fail/intrinsics/ptr_offset_unsigned_overflow.rs:LL:CC
    |
 LL |     let _ = unsafe { x.byte_add(usize::MAX) };
-   |                      ^^^^^^^^^^^^^^^^^^^^^^ overflowing pointer arithmetic: the total offset in bytes does not fit in an `isize`
+   |                      ^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/rem-by-zero.stderr b/src/tools/miri/tests/fail/intrinsics/rem-by-zero.stderr
index cb5ddc80dda..1864efbfee5 100644
--- a/src/tools/miri/tests/fail/intrinsics/rem-by-zero.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/rem-by-zero.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: calculating the remainder with a divisor of zero
   --> tests/fail/intrinsics/rem-by-zero.rs:LL:CC
    |
 LL |         let _n = unchecked_rem(3u32, 0);
-   |                  ^^^^^^^^^^^^^^^^^^^^^^ calculating the remainder with a divisor of zero
+   |                  ^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/simd-div-by-zero.stderr b/src/tools/miri/tests/fail/intrinsics/simd-div-by-zero.stderr
index b3579758f8f..7bea1799468 100644
--- a/src/tools/miri/tests/fail/intrinsics/simd-div-by-zero.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/simd-div-by-zero.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: dividing by zero
   --> tests/fail/intrinsics/simd-div-by-zero.rs:LL:CC
    |
 LL |         simd_div(x, y);
-   |         ^^^^^^^^^^^^^^ dividing by zero
+   |         ^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/simd-div-overflow.stderr b/src/tools/miri/tests/fail/intrinsics/simd-div-overflow.stderr
index 1144f8cf706..459212a9119 100644
--- a/src/tools/miri/tests/fail/intrinsics/simd-div-overflow.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/simd-div-overflow.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: overflow in signed division (dividing MIN by -1)
   --> tests/fail/intrinsics/simd-div-overflow.rs:LL:CC
    |
 LL |         simd_div(x, y);
-   |         ^^^^^^^^^^^^^^ overflow in signed division (dividing MIN by -1)
+   |         ^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/simd-extract.stderr b/src/tools/miri/tests/fail/intrinsics/simd-extract.stderr
index fdf08e8303f..bd9dafb6864 100644
--- a/src/tools/miri/tests/fail/intrinsics/simd-extract.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/simd-extract.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `simd_extract` index 4 is out-of-bounds of vector wit
   --> tests/fail/intrinsics/simd-extract.rs:LL:CC
    |
 LL |     let _x: i32 = unsafe { std::intrinsics::simd::simd_extract(v, 4) };
-   |                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `simd_extract` index 4 is out-of-bounds of vector with length 4
+   |                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/simd-float-to-int.stderr b/src/tools/miri/tests/fail/intrinsics/simd-float-to-int.stderr
index e34ebd3d7f7..04e9cb338cd 100644
--- a/src/tools/miri/tests/fail/intrinsics/simd-float-to-int.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/simd-float-to-int.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `simd_cast` intrinsic called on 3.40282347E+38f32 whi
   --> tests/fail/intrinsics/simd-float-to-int.rs:LL:CC
    |
 LL |         let _x: i32x2 = f32x2::from_array([f32::MAX, f32::MIN]).to_int_unchecked();
-   |                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `simd_cast` intrinsic called on 3.40282347E+38f32 which cannot be represented in target type `i32`
+   |                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/simd-gather.stderr b/src/tools/miri/tests/fail/intrinsics/simd-gather.stderr
index e91d5d2185f..d70f406e45b 100644
--- a/src/tools/miri/tests/fail/intrinsics/simd-gather.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/simd-gather.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: memory access failed: attempting to access 1 byte, bu
   --> tests/fail/intrinsics/simd-gather.rs:LL:CC
    |
 LL |         let _result = Simd::gather_select_unchecked(&vec, Mask::splat(true), idxs, Simd::splat(0));
-   |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ memory access failed: attempting to access 1 byte, but got ALLOC+0x9 which is at or beyond the end of the allocation of size 9 bytes
+   |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/simd-reduce-invalid-bool.stderr b/src/tools/miri/tests/fail/intrinsics/simd-reduce-invalid-bool.stderr
index db76897faed..0d8b96b7985 100644
--- a/src/tools/miri/tests/fail/intrinsics/simd-reduce-invalid-bool.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/simd-reduce-invalid-bool.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: each element of a SIMD mask must be all-0-bits or all
   --> tests/fail/intrinsics/simd-reduce-invalid-bool.rs:LL:CC
    |
 LL |         simd_reduce_any(x);
-   |         ^^^^^^^^^^^^^^^^^^ each element of a SIMD mask must be all-0-bits or all-1-bits
+   |         ^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/simd-rem-by-zero.stderr b/src/tools/miri/tests/fail/intrinsics/simd-rem-by-zero.stderr
index ec136a62ff2..c58731fab8c 100644
--- a/src/tools/miri/tests/fail/intrinsics/simd-rem-by-zero.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/simd-rem-by-zero.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: calculating the remainder with a divisor of zero
   --> tests/fail/intrinsics/simd-rem-by-zero.rs:LL:CC
    |
 LL |         simd_rem(x, y);
-   |         ^^^^^^^^^^^^^^ calculating the remainder with a divisor of zero
+   |         ^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/simd-scatter.stderr b/src/tools/miri/tests/fail/intrinsics/simd-scatter.stderr
index 56c8e7b38b6..52032254aff 100644
--- a/src/tools/miri/tests/fail/intrinsics/simd-scatter.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/simd-scatter.stderr
@@ -7,7 +7,7 @@ LL | |             &mut vec,
 LL | |             Mask::splat(true),
 LL | |             idxs,
 LL | |         );
-   | |_________^ memory access failed: attempting to access 1 byte, but got ALLOC+0x9 which is at or beyond the end of the allocation of size 9 bytes
+   | |_________^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/simd-select-invalid-bool.stderr b/src/tools/miri/tests/fail/intrinsics/simd-select-invalid-bool.stderr
index 52b497046d0..9a681173a17 100644
--- a/src/tools/miri/tests/fail/intrinsics/simd-select-invalid-bool.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/simd-select-invalid-bool.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: each element of a SIMD mask must be all-0-bits or all
   --> tests/fail/intrinsics/simd-select-invalid-bool.rs:LL:CC
    |
 LL |         simd_select(x, x, x);
-   |         ^^^^^^^^^^^^^^^^^^^^ each element of a SIMD mask must be all-0-bits or all-1-bits
+   |         ^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/simd-shl-too-far.stderr b/src/tools/miri/tests/fail/intrinsics/simd-shl-too-far.stderr
index f7dfd0743f1..f1387e2c27f 100644
--- a/src/tools/miri/tests/fail/intrinsics/simd-shl-too-far.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/simd-shl-too-far.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: overflowing shift by 100 in `simd_shl` in lane 0
   --> tests/fail/intrinsics/simd-shl-too-far.rs:LL:CC
    |
 LL |         simd_shl(x, y);
-   |         ^^^^^^^^^^^^^^ overflowing shift by 100 in `simd_shl` in lane 0
+   |         ^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/simd-shr-too-far.stderr b/src/tools/miri/tests/fail/intrinsics/simd-shr-too-far.stderr
index 52259635d21..3c14b7fb4a2 100644
--- a/src/tools/miri/tests/fail/intrinsics/simd-shr-too-far.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/simd-shr-too-far.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: overflowing shift by 40 in `simd_shr` in lane 1
   --> tests/fail/intrinsics/simd-shr-too-far.rs:LL:CC
    |
 LL |         simd_shr(x, y);
-   |         ^^^^^^^^^^^^^^ overflowing shift by 40 in `simd_shr` in lane 1
+   |         ^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/typed-swap-invalid-array.stderr b/src/tools/miri/tests/fail/intrinsics/typed-swap-invalid-array.stderr
index 5884d13a2ad..7db79582992 100644
--- a/src/tools/miri/tests/fail/intrinsics/typed-swap-invalid-array.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/typed-swap-invalid-array.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value at [0]: encountered 0x02,
   --> tests/fail/intrinsics/typed-swap-invalid-array.rs:LL:CC
    |
 LL |         typed_swap_nonoverlapping(a, b);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ constructing invalid value at [0]: encountered 0x02, but expected a boolean
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/typed-swap-invalid-scalar.left.stderr b/src/tools/miri/tests/fail/intrinsics/typed-swap-invalid-scalar.left.stderr
index 9804233c7fa..7edf72205d9 100644
--- a/src/tools/miri/tests/fail/intrinsics/typed-swap-invalid-scalar.left.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/typed-swap-invalid-scalar.left.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value: encountered 0x02, but exp
   --> tests/fail/intrinsics/typed-swap-invalid-scalar.rs:LL:CC
    |
 LL |         typed_swap_nonoverlapping(a, b);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ constructing invalid value: encountered 0x02, but expected a boolean
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/typed-swap-invalid-scalar.right.stderr b/src/tools/miri/tests/fail/intrinsics/typed-swap-invalid-scalar.right.stderr
index 54b21f155ca..aece0b6cb98 100644
--- a/src/tools/miri/tests/fail/intrinsics/typed-swap-invalid-scalar.right.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/typed-swap-invalid-scalar.right.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value: encountered 0x03, but exp
   --> tests/fail/intrinsics/typed-swap-invalid-scalar.rs:LL:CC
    |
 LL |         typed_swap_nonoverlapping(a, b);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ constructing invalid value: encountered 0x03, but expected a boolean
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/typed-swap-overlap.stderr b/src/tools/miri/tests/fail/intrinsics/typed-swap-overlap.stderr
index 6d578841fe5..fb50db74a20 100644
--- a/src/tools/miri/tests/fail/intrinsics/typed-swap-overlap.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/typed-swap-overlap.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `copy_nonoverlapping` called on overlapping ranges
   --> tests/fail/intrinsics/typed-swap-overlap.rs:LL:CC
    |
 LL |         typed_swap_nonoverlapping(a, a);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `copy_nonoverlapping` called on overlapping ranges
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/unchecked_add1.stderr b/src/tools/miri/tests/fail/intrinsics/unchecked_add1.stderr
index f6fe453587f..649009cade9 100644
--- a/src/tools/miri/tests/fail/intrinsics/unchecked_add1.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/unchecked_add1.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: arithmetic overflow in `unchecked_add`
   --> tests/fail/intrinsics/unchecked_add1.rs:LL:CC
    |
 LL |     let _val = unsafe { 40000u16.unchecked_add(30000) };
-   |                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ arithmetic overflow in `unchecked_add`
+   |                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/unchecked_add2.stderr b/src/tools/miri/tests/fail/intrinsics/unchecked_add2.stderr
index 0fd1e8ff91c..eec74a304ad 100644
--- a/src/tools/miri/tests/fail/intrinsics/unchecked_add2.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/unchecked_add2.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: arithmetic overflow in `unchecked_add`
   --> tests/fail/intrinsics/unchecked_add2.rs:LL:CC
    |
 LL |     let _val = unsafe { (-30000i16).unchecked_add(-8000) };
-   |                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ arithmetic overflow in `unchecked_add`
+   |                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/unchecked_div1.stderr b/src/tools/miri/tests/fail/intrinsics/unchecked_div1.stderr
index f7aef4914e2..5f3422f19b3 100644
--- a/src/tools/miri/tests/fail/intrinsics/unchecked_div1.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/unchecked_div1.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: overflow in signed division (dividing MIN by -1)
   --> tests/fail/intrinsics/unchecked_div1.rs:LL:CC
    |
 LL |         std::intrinsics::unchecked_div(i16::MIN, -1);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ overflow in signed division (dividing MIN by -1)
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/unchecked_mul1.stderr b/src/tools/miri/tests/fail/intrinsics/unchecked_mul1.stderr
index ad7bbaebeec..f9d5a4db933 100644
--- a/src/tools/miri/tests/fail/intrinsics/unchecked_mul1.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/unchecked_mul1.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: arithmetic overflow in `unchecked_mul`
   --> tests/fail/intrinsics/unchecked_mul1.rs:LL:CC
    |
 LL |     let _val = unsafe { 300u16.unchecked_mul(250u16) };
-   |                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ arithmetic overflow in `unchecked_mul`
+   |                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/unchecked_mul2.stderr b/src/tools/miri/tests/fail/intrinsics/unchecked_mul2.stderr
index 75de5d2338d..a2c19043f92 100644
--- a/src/tools/miri/tests/fail/intrinsics/unchecked_mul2.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/unchecked_mul2.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: arithmetic overflow in `unchecked_mul`
   --> tests/fail/intrinsics/unchecked_mul2.rs:LL:CC
    |
 LL |     let _val = unsafe { 1_000_000_000i32.unchecked_mul(-4) };
-   |                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ arithmetic overflow in `unchecked_mul`
+   |                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/unchecked_shl.stderr b/src/tools/miri/tests/fail/intrinsics/unchecked_shl.stderr
index fcf6e1aea0c..94d0bc0d111 100644
--- a/src/tools/miri/tests/fail/intrinsics/unchecked_shl.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/unchecked_shl.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: overflowing shift by 8 in `unchecked_shl`
   --> tests/fail/intrinsics/unchecked_shl.rs:LL:CC
    |
 LL |         let _n = 1i8.unchecked_shl(8);
-   |                  ^^^^^^^^^^^^^^^^^^^^ overflowing shift by 8 in `unchecked_shl`
+   |                  ^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/unchecked_shl2.stderr b/src/tools/miri/tests/fail/intrinsics/unchecked_shl2.stderr
index c38139e4c29..8c79a1980b7 100644
--- a/src/tools/miri/tests/fail/intrinsics/unchecked_shl2.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/unchecked_shl2.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: overflowing shift by -1 in `unchecked_shl`
   --> tests/fail/intrinsics/unchecked_shl2.rs:LL:CC
    |
 LL |         let _n = intrinsics::unchecked_shl(1i8, -1);
-   |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ overflowing shift by -1 in `unchecked_shl`
+   |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/unchecked_shr.stderr b/src/tools/miri/tests/fail/intrinsics/unchecked_shr.stderr
index e95227fe89f..4067437bf0f 100644
--- a/src/tools/miri/tests/fail/intrinsics/unchecked_shr.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/unchecked_shr.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: overflowing shift by 64 in `unchecked_shr`
   --> tests/fail/intrinsics/unchecked_shr.rs:LL:CC
    |
 LL |         let _n = 1i64.unchecked_shr(64);
-   |                  ^^^^^^^^^^^^^^^^^^^^^^ overflowing shift by 64 in `unchecked_shr`
+   |                  ^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/unchecked_sub1.stderr b/src/tools/miri/tests/fail/intrinsics/unchecked_sub1.stderr
index fdd30186c3c..b5914137a1c 100644
--- a/src/tools/miri/tests/fail/intrinsics/unchecked_sub1.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/unchecked_sub1.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: arithmetic overflow in `unchecked_sub`
   --> tests/fail/intrinsics/unchecked_sub1.rs:LL:CC
    |
 LL |     let _val = unsafe { 14u32.unchecked_sub(22) };
-   |                         ^^^^^^^^^^^^^^^^^^^^^^^ arithmetic overflow in `unchecked_sub`
+   |                         ^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/unchecked_sub2.stderr b/src/tools/miri/tests/fail/intrinsics/unchecked_sub2.stderr
index c27bb32c9da..34227ddc051 100644
--- a/src/tools/miri/tests/fail/intrinsics/unchecked_sub2.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/unchecked_sub2.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: arithmetic overflow in `unchecked_sub`
   --> tests/fail/intrinsics/unchecked_sub2.rs:LL:CC
    |
 LL |     let _val = unsafe { 30000i16.unchecked_sub(-7000) };
-   |                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ arithmetic overflow in `unchecked_sub`
+   |                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/uninit_uninhabited_type.stderr b/src/tools/miri/tests/fail/intrinsics/uninit_uninhabited_type.stderr
index ba96e595bee..3db8a5be205 100644
--- a/src/tools/miri/tests/fail/intrinsics/uninit_uninhabited_type.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/uninit_uninhabited_type.stderr
@@ -8,7 +8,7 @@ error: abnormal termination: the program aborted execution
   --> RUSTLIB/std/src/sys/pal/PLATFORM/mod.rs:LL:CC
    |
 LL | ABORT()
-   | ^ the program aborted execution
+   | ^ abnormal termination occurred here
    |
    = note: BACKTRACE:
    = note: inside `std::sys::pal::PLATFORM::abort_internal` at RUSTLIB/std/src/sys/pal/PLATFORM/mod.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/intrinsics/write_bytes_overflow.stderr b/src/tools/miri/tests/fail/intrinsics/write_bytes_overflow.stderr
index 71f53a31992..e8c23463e86 100644
--- a/src/tools/miri/tests/fail/intrinsics/write_bytes_overflow.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/write_bytes_overflow.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: overflow computing total size of `write_bytes`
   --> tests/fail/intrinsics/write_bytes_overflow.rs:LL:CC
    |
 LL |         (&mut y as *mut i32).write_bytes(0u8, 1usize << (mem::size_of::<usize>() * 8 - 1));
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ overflow computing total size of `write_bytes`
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/intrinsics/zero_fn_ptr.stderr b/src/tools/miri/tests/fail/intrinsics/zero_fn_ptr.stderr
index 7e1f4160cc0..a1e476328b0 100644
--- a/src/tools/miri/tests/fail/intrinsics/zero_fn_ptr.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/zero_fn_ptr.stderr
@@ -8,7 +8,7 @@ error: abnormal termination: the program aborted execution
   --> RUSTLIB/std/src/sys/pal/PLATFORM/mod.rs:LL:CC
    |
 LL | ABORT()
-   | ^ the program aborted execution
+   | ^ abnormal termination occurred here
    |
    = note: BACKTRACE:
    = note: inside `std::sys::pal::PLATFORM::abort_internal` at RUSTLIB/std/src/sys/pal/PLATFORM/mod.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/issue-miri-1112.stderr b/src/tools/miri/tests/fail/issue-miri-1112.stderr
index ffbbd269216..98f04ff1af6 100644
--- a/src/tools/miri/tests/fail/issue-miri-1112.stderr
+++ b/src/tools/miri/tests/fail/issue-miri-1112.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value: encountered $HEX[ALLOC]<T
   --> tests/fail/issue-miri-1112.rs:LL:CC
    |
 LL |         let obj = std::mem::transmute::<FatPointer, *mut FunnyPointer>(obj);
-   |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ constructing invalid value: encountered $HEX[ALLOC]<TAG>, but expected a vtable pointer
+   |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/issue-miri-3288-ice-symbolic-alignment-extern-static.stderr b/src/tools/miri/tests/fail/issue-miri-3288-ice-symbolic-alignment-extern-static.stderr
index 91f90959550..3d62d02559d 100644
--- a/src/tools/miri/tests/fail/issue-miri-3288-ice-symbolic-alignment-extern-static.stderr
+++ b/src/tools/miri/tests/fail/issue-miri-3288-ice-symbolic-alignment-extern-static.stderr
@@ -2,7 +2,7 @@ error: unsupported operation: extern static `_dispatch_queue_attr_concurrent` is
   --> tests/fail/issue-miri-3288-ice-symbolic-alignment-extern-static.rs:LL:CC
    |
 LL |     let _val = *DISPATCH_QUEUE_CONCURRENT;
-   |                 ^^^^^^^^^^^^^^^^^^^^^^^^^ extern static `_dispatch_queue_attr_concurrent` is not supported by Miri
+   |                 ^^^^^^^^^^^^^^^^^^^^^^^^^ unsupported operation occurred here
    |
    = help: this is likely not a bug in the program; it indicates that the program performed an operation that Miri does not support
    = note: BACKTRACE:
diff --git a/src/tools/miri/tests/fail/layout_cycle.stderr b/src/tools/miri/tests/fail/layout_cycle.stderr
index 9f53de35239..c233f85063c 100644
--- a/src/tools/miri/tests/fail/layout_cycle.stderr
+++ b/src/tools/miri/tests/fail/layout_cycle.stderr
@@ -8,7 +8,7 @@ error: post-monomorphization error: a cycle occurred during layout computation
   --> RUSTLIB/core/src/mem/mod.rs:LL:CC
    |
 LL |     intrinsics::size_of::<T>()
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^ a cycle occurred during layout computation
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^ post-monomorphization error occurred here
    |
    = note: BACKTRACE:
    = note: inside `std::mem::size_of::<S<S<()>>>` at RUSTLIB/core/src/mem/mod.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/modifying_constants.stderr b/src/tools/miri/tests/fail/modifying_constants.stderr
index 2d8e4dfd8a5..80026a81a57 100644
--- a/src/tools/miri/tests/fail/modifying_constants.stderr
+++ b/src/tools/miri/tests/fail/modifying_constants.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: writing to ALLOC which is read-only
   --> tests/fail/modifying_constants.rs:LL:CC
    |
 LL |     *y = 42;
-   |     ^^^^^^^ writing to ALLOC which is read-only
+   |     ^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/never_match_never.stderr b/src/tools/miri/tests/fail/never_match_never.stderr
index e59a028b15b..c29a4f6b2d1 100644
--- a/src/tools/miri/tests/fail/never_match_never.stderr
+++ b/src/tools/miri/tests/fail/never_match_never.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: entering unreachable code
   --> tests/fail/never_match_never.rs:LL:CC
    |
 LL |     unsafe { match (*ptr).1 {} }
-   |                    ^^^^^^^^ entering unreachable code
+   |                    ^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/never_say_never.stderr b/src/tools/miri/tests/fail/never_say_never.stderr
index 7d2952003b2..c8fefa462d3 100644
--- a/src/tools/miri/tests/fail/never_say_never.stderr
+++ b/src/tools/miri/tests/fail/never_say_never.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: entering unreachable code
   --> tests/fail/never_say_never.rs:LL:CC
    |
 LL |     f(x)
-   |     ^^^^ entering unreachable code
+   |     ^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/never_transmute_humans.stderr b/src/tools/miri/tests/fail/never_transmute_humans.stderr
index a00c244841e..5c968dfbaea 100644
--- a/src/tools/miri/tests/fail/never_transmute_humans.stderr
+++ b/src/tools/miri/tests/fail/never_transmute_humans.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: entering unreachable code
   --> tests/fail/never_transmute_humans.rs:LL:CC
    |
 LL |         std::mem::transmute::<Human, !>(Human)
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ entering unreachable code
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/never_transmute_void.stderr b/src/tools/miri/tests/fail/never_transmute_void.stderr
index 1906a68bffe..10ef783f220 100644
--- a/src/tools/miri/tests/fail/never_transmute_void.stderr
+++ b/src/tools/miri/tests/fail/never_transmute_void.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: entering unreachable code
   --> tests/fail/never_transmute_void.rs:LL:CC
    |
 LL |         match v.0 {}
-   |               ^^^ entering unreachable code
+   |               ^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/overlapping_assignment.stderr b/src/tools/miri/tests/fail/overlapping_assignment.stderr
index 0ce2e4a0981..a479e8be648 100644
--- a/src/tools/miri/tests/fail/overlapping_assignment.stderr
+++ b/src/tools/miri/tests/fail/overlapping_assignment.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: `copy_nonoverlapping` called on overlapping ranges
   --> tests/fail/overlapping_assignment.rs:LL:CC
    |
 LL |             *ptr1 = *ptr2;
-   |             ^^^^^^^^^^^^^ `copy_nonoverlapping` called on overlapping ranges
+   |             ^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/panic/abort_unwind.stderr b/src/tools/miri/tests/fail/panic/abort_unwind.stderr
index e6668b09f66..81d560c27ec 100644
--- a/src/tools/miri/tests/fail/panic/abort_unwind.stderr
+++ b/src/tools/miri/tests/fail/panic/abort_unwind.stderr
@@ -12,7 +12,7 @@ error: abnormal termination: the program aborted execution
   --> RUSTLIB/std/src/sys/pal/PLATFORM/mod.rs:LL:CC
    |
 LL | ABORT()
-   | ^ the program aborted execution
+   | ^ abnormal termination occurred here
    |
    = note: BACKTRACE:
    = note: inside `std::sys::pal::PLATFORM::abort_internal` at RUSTLIB/std/src/sys/pal/PLATFORM/mod.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/panic/bad_unwind.stderr b/src/tools/miri/tests/fail/panic/bad_unwind.stderr
index 8c269eae62a..b8404c4e457 100644
--- a/src/tools/miri/tests/fail/panic/bad_unwind.stderr
+++ b/src/tools/miri/tests/fail/panic/bad_unwind.stderr
@@ -7,7 +7,7 @@ error: Undefined Behavior: unwinding past a stack frame that does not allow unwi
   --> tests/fail/panic/bad_unwind.rs:LL:CC
    |
 LL |     std::panic::catch_unwind(|| unwind()).unwrap_err();
-   |                                 ^^^^^^^^ unwinding past a stack frame that does not allow unwinding
+   |                                 ^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/panic/double_panic.stderr b/src/tools/miri/tests/fail/panic/double_panic.stderr
index 67f88955def..bc6cce93d41 100644
--- a/src/tools/miri/tests/fail/panic/double_panic.stderr
+++ b/src/tools/miri/tests/fail/panic/double_panic.stderr
@@ -15,7 +15,7 @@ error: abnormal termination: the program aborted execution
   --> RUSTLIB/std/src/sys/pal/PLATFORM/mod.rs:LL:CC
    |
 LL | ABORT()
-   | ^ the program aborted execution
+   | ^ abnormal termination occurred here
    |
    = note: BACKTRACE:
    = note: inside `std::sys::pal::PLATFORM::abort_internal` at RUSTLIB/std/src/sys/pal/PLATFORM/mod.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/panic/no_std.stderr b/src/tools/miri/tests/fail/panic/no_std.stderr
index b1d98ffc7a9..dbd29e43069 100644
--- a/src/tools/miri/tests/fail/panic/no_std.stderr
+++ b/src/tools/miri/tests/fail/panic/no_std.stderr
@@ -4,7 +4,7 @@ error: abnormal termination: the program aborted execution
   --> tests/fail/panic/no_std.rs:LL:CC
    |
 LL |     core::intrinsics::abort();
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^ the program aborted execution
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^ abnormal termination occurred here
    |
    = note: BACKTRACE:
    = note: inside `panic_handler` at tests/fail/panic/no_std.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/panic/panic_abort1.stderr b/src/tools/miri/tests/fail/panic/panic_abort1.stderr
index 6d56874ebde..61bc9a7a495 100644
--- a/src/tools/miri/tests/fail/panic/panic_abort1.stderr
+++ b/src/tools/miri/tests/fail/panic/panic_abort1.stderr
@@ -7,7 +7,7 @@ error: abnormal termination: the program aborted execution
   --> RUSTLIB/std/src/sys/pal/PLATFORM/mod.rs:LL:CC
    |
 LL | ABORT()
-   | ^ the program aborted execution
+   | ^ abnormal termination occurred here
    |
    = note: BACKTRACE:
    = note: inside `std::sys::pal::PLATFORM::abort_internal` at RUSTLIB/std/src/sys/pal/PLATFORM/mod.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/panic/panic_abort2.stderr b/src/tools/miri/tests/fail/panic/panic_abort2.stderr
index dbb56f13f48..a7a42f8174e 100644
--- a/src/tools/miri/tests/fail/panic/panic_abort2.stderr
+++ b/src/tools/miri/tests/fail/panic/panic_abort2.stderr
@@ -7,7 +7,7 @@ error: abnormal termination: the program aborted execution
   --> RUSTLIB/std/src/sys/pal/PLATFORM/mod.rs:LL:CC
    |
 LL | ABORT()
-   | ^ the program aborted execution
+   | ^ abnormal termination occurred here
    |
    = note: BACKTRACE:
    = note: inside `std::sys::pal::PLATFORM::abort_internal` at RUSTLIB/std/src/sys/pal/PLATFORM/mod.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/panic/panic_abort3.stderr b/src/tools/miri/tests/fail/panic/panic_abort3.stderr
index 7f0564879e4..ba1f11065ea 100644
--- a/src/tools/miri/tests/fail/panic/panic_abort3.stderr
+++ b/src/tools/miri/tests/fail/panic/panic_abort3.stderr
@@ -7,7 +7,7 @@ error: abnormal termination: the program aborted execution
   --> RUSTLIB/std/src/sys/pal/PLATFORM/mod.rs:LL:CC
    |
 LL | ABORT()
-   | ^ the program aborted execution
+   | ^ abnormal termination occurred here
    |
    = note: BACKTRACE:
    = note: inside `std::sys::pal::PLATFORM::abort_internal` at RUSTLIB/std/src/sys/pal/PLATFORM/mod.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/panic/panic_abort4.stderr b/src/tools/miri/tests/fail/panic/panic_abort4.stderr
index ce6910b9933..1464c1fcc7c 100644
--- a/src/tools/miri/tests/fail/panic/panic_abort4.stderr
+++ b/src/tools/miri/tests/fail/panic/panic_abort4.stderr
@@ -7,7 +7,7 @@ error: abnormal termination: the program aborted execution
   --> RUSTLIB/std/src/sys/pal/PLATFORM/mod.rs:LL:CC
    |
 LL | ABORT()
-   | ^ the program aborted execution
+   | ^ abnormal termination occurred here
    |
    = note: BACKTRACE:
    = note: inside `std::sys::pal::PLATFORM::abort_internal` at RUSTLIB/std/src/sys/pal/PLATFORM/mod.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/panic/unwind_panic_abort.stderr b/src/tools/miri/tests/fail/panic/unwind_panic_abort.stderr
index 7291f5bce8d..289cbb43bcf 100644
--- a/src/tools/miri/tests/fail/panic/unwind_panic_abort.stderr
+++ b/src/tools/miri/tests/fail/panic/unwind_panic_abort.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: unwinding past a stack frame that does not allow unwi
   --> tests/fail/panic/unwind_panic_abort.rs:LL:CC
    |
 LL |         miri_start_unwind(&mut 0);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^ unwinding past a stack frame that does not allow unwinding
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/provenance/int_copy_looses_provenance0.stderr b/src/tools/miri/tests/fail/provenance/int_copy_looses_provenance0.stderr
index 24a8d787407..97bda83d05a 100644
--- a/src/tools/miri/tests/fail/provenance/int_copy_looses_provenance0.stderr
+++ b/src/tools/miri/tests/fail/provenance/int_copy_looses_provenance0.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value: encountered a dangling re
   --> tests/fail/provenance/int_copy_looses_provenance0.rs:LL:CC
    |
 LL |     let _val = unsafe { *ptr.read() };
-   |                          ^^^^^^^^^^ constructing invalid value: encountered a dangling reference ($HEX[noalloc] has no provenance)
+   |                          ^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/provenance/int_copy_looses_provenance1.stderr b/src/tools/miri/tests/fail/provenance/int_copy_looses_provenance1.stderr
index 14855a723b4..a4d725f9ae1 100644
--- a/src/tools/miri/tests/fail/provenance/int_copy_looses_provenance1.stderr
+++ b/src/tools/miri/tests/fail/provenance/int_copy_looses_provenance1.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value: encountered a dangling re
   --> tests/fail/provenance/int_copy_looses_provenance1.rs:LL:CC
    |
 LL |     let _val = unsafe { *ptr.read() };
-   |                          ^^^^^^^^^^ constructing invalid value: encountered a dangling reference ($HEX[noalloc] has no provenance)
+   |                          ^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/provenance/int_copy_looses_provenance2.stderr b/src/tools/miri/tests/fail/provenance/int_copy_looses_provenance2.stderr
index 2d5b9783098..f00eccf0719 100644
--- a/src/tools/miri/tests/fail/provenance/int_copy_looses_provenance2.stderr
+++ b/src/tools/miri/tests/fail/provenance/int_copy_looses_provenance2.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value: encountered a dangling re
   --> tests/fail/provenance/int_copy_looses_provenance2.rs:LL:CC
    |
 LL |     let _val = unsafe { *ptr.read() };
-   |                          ^^^^^^^^^^ constructing invalid value: encountered a dangling reference ($HEX[noalloc] has no provenance)
+   |                          ^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/provenance/int_copy_looses_provenance3.stderr b/src/tools/miri/tests/fail/provenance/int_copy_looses_provenance3.stderr
index 4e741fe8329..432d869af9b 100644
--- a/src/tools/miri/tests/fail/provenance/int_copy_looses_provenance3.stderr
+++ b/src/tools/miri/tests/fail/provenance/int_copy_looses_provenance3.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: memory access failed: attempting to access 4 bytes, b
   --> tests/fail/provenance/int_copy_looses_provenance3.rs:LL:CC
    |
 LL |     let _val = unsafe { *ptr };
-   |                         ^^^^ memory access failed: attempting to access 4 bytes, but got $HEX[noalloc] which is a dangling pointer (it has no provenance)
+   |                         ^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/provenance/pointer_partial_overwrite.stderr b/src/tools/miri/tests/fail/provenance/pointer_partial_overwrite.stderr
index 370f9463b73..e1d990771f2 100644
--- a/src/tools/miri/tests/fail/provenance/pointer_partial_overwrite.stderr
+++ b/src/tools/miri/tests/fail/provenance/pointer_partial_overwrite.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: memory access failed: attempting to access 4 bytes, b
   --> tests/fail/provenance/pointer_partial_overwrite.rs:LL:CC
    |
 LL |     let x = *p;
-   |             ^^ memory access failed: attempting to access 4 bytes, but got $HEX[noalloc] which is a dangling pointer (it has no provenance)
+   |             ^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/provenance/provenance_transmute.stderr b/src/tools/miri/tests/fail/provenance/provenance_transmute.stderr
index 38e2e19009a..013c39a2246 100644
--- a/src/tools/miri/tests/fail/provenance/provenance_transmute.stderr
+++ b/src/tools/miri/tests/fail/provenance/provenance_transmute.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: memory access failed: attempting to access 1 byte, bu
   --> tests/fail/provenance/provenance_transmute.rs:LL:CC
    |
 LL |         let _val = *left_ptr;
-   |                    ^^^^^^^^^ memory access failed: attempting to access 1 byte, but got $HEX[noalloc] which is a dangling pointer (it has no provenance)
+   |                    ^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/provenance/ptr_copy_loses_partial_provenance0.stderr b/src/tools/miri/tests/fail/provenance/ptr_copy_loses_partial_provenance0.stderr
index 5225ab32865..0c97c990f92 100644
--- a/src/tools/miri/tests/fail/provenance/ptr_copy_loses_partial_provenance0.stderr
+++ b/src/tools/miri/tests/fail/provenance/ptr_copy_loses_partial_provenance0.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: memory access failed: attempting to access 4 bytes, b
   --> tests/fail/provenance/ptr_copy_loses_partial_provenance0.rs:LL:CC
    |
 LL |         let _val = *ptr;
-   |                    ^^^^ memory access failed: attempting to access 4 bytes, but got $HEX[noalloc] which is a dangling pointer (it has no provenance)
+   |                    ^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/provenance/ptr_copy_loses_partial_provenance1.stderr b/src/tools/miri/tests/fail/provenance/ptr_copy_loses_partial_provenance1.stderr
index c17c98fa105..c29cf2df811 100644
--- a/src/tools/miri/tests/fail/provenance/ptr_copy_loses_partial_provenance1.stderr
+++ b/src/tools/miri/tests/fail/provenance/ptr_copy_loses_partial_provenance1.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: memory access failed: attempting to access 4 bytes, b
   --> tests/fail/provenance/ptr_copy_loses_partial_provenance1.rs:LL:CC
    |
 LL |         let _val = *ptr;
-   |                    ^^^^ memory access failed: attempting to access 4 bytes, but got $HEX[noalloc] which is a dangling pointer (it has no provenance)
+   |                    ^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/provenance/ptr_int_unexposed.stderr b/src/tools/miri/tests/fail/provenance/ptr_int_unexposed.stderr
index 78290d4ed63..23c2fce8403 100644
--- a/src/tools/miri/tests/fail/provenance/ptr_int_unexposed.stderr
+++ b/src/tools/miri/tests/fail/provenance/ptr_int_unexposed.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: memory access failed: attempting to access 4 bytes, b
   --> tests/fail/provenance/ptr_int_unexposed.rs:LL:CC
    |
 LL |     assert_eq!(unsafe { *ptr }, 3);
-   |                         ^^^^ memory access failed: attempting to access 4 bytes, but got $HEX[noalloc] which is a dangling pointer (it has no provenance)
+   |                         ^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/provenance/ptr_invalid.stderr b/src/tools/miri/tests/fail/provenance/ptr_invalid.stderr
index ff73fbb9d1b..dffaf236bed 100644
--- a/src/tools/miri/tests/fail/provenance/ptr_invalid.stderr
+++ b/src/tools/miri/tests/fail/provenance/ptr_invalid.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: memory access failed: attempting to access 4 bytes, b
   --> tests/fail/provenance/ptr_invalid.rs:LL:CC
    |
 LL |     let _val = unsafe { *xptr_invalid };
-   |                         ^^^^^^^^^^^^^ memory access failed: attempting to access 4 bytes, but got $HEX[noalloc] which is a dangling pointer (it has no provenance)
+   |                         ^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/provenance/ptr_invalid_offset.stderr b/src/tools/miri/tests/fail/provenance/ptr_invalid_offset.stderr
index 07556540f13..fab5fe0f60c 100644
--- a/src/tools/miri/tests/fail/provenance/ptr_invalid_offset.stderr
+++ b/src/tools/miri/tests/fail/provenance/ptr_invalid_offset.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: in-bounds pointer arithmetic failed: attempting to of
   --> tests/fail/provenance/ptr_invalid_offset.rs:LL:CC
    |
 LL |     let _ = unsafe { roundtrip.offset(1) };
-   |                      ^^^^^^^^^^^^^^^^^^^ in-bounds pointer arithmetic failed: attempting to offset pointer by 1 byte, but got $HEX[noalloc] which is a dangling pointer (it has no provenance)
+   |                      ^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/provenance/strict_provenance_cast.stderr b/src/tools/miri/tests/fail/provenance/strict_provenance_cast.stderr
index ab7d8db1a31..e203911c667 100644
--- a/src/tools/miri/tests/fail/provenance/strict_provenance_cast.stderr
+++ b/src/tools/miri/tests/fail/provenance/strict_provenance_cast.stderr
@@ -2,7 +2,7 @@ error: unsupported operation: integer-to-pointer casts and `ptr::with_exposed_pr
   --> tests/fail/provenance/strict_provenance_cast.rs:LL:CC
    |
 LL |     let _ptr = std::ptr::with_exposed_provenance::<i32>(addr);
-   |                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ integer-to-pointer casts and `ptr::with_exposed_provenance` are not supported with `-Zmiri-strict-provenance`
+   |                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ unsupported operation occurred here
    |
    = help: use Strict Provenance APIs (https://doc.rust-lang.org/nightly/std/ptr/index.html#strict-provenance, https://crates.io/crates/sptr) instead
    = note: BACKTRACE:
diff --git a/src/tools/miri/tests/fail/ptr_swap_nonoverlapping.stderr b/src/tools/miri/tests/fail/ptr_swap_nonoverlapping.stderr
index b4dadeecaa8..b893220426c 100644
--- a/src/tools/miri/tests/fail/ptr_swap_nonoverlapping.stderr
+++ b/src/tools/miri/tests/fail/ptr_swap_nonoverlapping.stderr
@@ -10,7 +10,7 @@ error: abnormal termination: the program aborted execution
   --> RUSTLIB/std/src/sys/pal/PLATFORM/mod.rs:LL:CC
    |
 LL | ABORT()
-   | ^ the program aborted execution
+   | ^ abnormal termination occurred here
    |
    = note: BACKTRACE:
    = note: inside `std::sys::pal::PLATFORM::abort_internal` at RUSTLIB/std/src/sys/pal/PLATFORM/mod.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/rc_as_ptr.stderr b/src/tools/miri/tests/fail/rc_as_ptr.stderr
index e1d0e5780a0..5c6bda35af6 100644
--- a/src/tools/miri/tests/fail/rc_as_ptr.stderr
+++ b/src/tools/miri/tests/fail/rc_as_ptr.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: pointer not dereferenceable: ALLOC has been freed, so
   --> tests/fail/rc_as_ptr.rs:LL:CC
    |
 LL |     assert_eq!(42, **unsafe { &*Weak::as_ptr(&weak) });
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ pointer not dereferenceable: ALLOC has been freed, so this pointer is dangling
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/read_from_trivial_switch.stderr b/src/tools/miri/tests/fail/read_from_trivial_switch.stderr
index 6b3d4539b96..923d836ee0c 100644
--- a/src/tools/miri/tests/fail/read_from_trivial_switch.stderr
+++ b/src/tools/miri/tests/fail/read_from_trivial_switch.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: using uninitialized data, but this operation requires
   --> tests/fail/read_from_trivial_switch.rs:LL:CC
    |
 LL |     let &(0 | _) = bad_ref;
-   |         ^^^^^^^^ using uninitialized data, but this operation requires initialized memory
+   |         ^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/reading_half_a_pointer.stderr b/src/tools/miri/tests/fail/reading_half_a_pointer.stderr
index 61fb9cd4e52..fe2bc6da2f8 100644
--- a/src/tools/miri/tests/fail/reading_half_a_pointer.stderr
+++ b/src/tools/miri/tests/fail/reading_half_a_pointer.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: memory access failed: attempting to access 1 byte, bu
   --> tests/fail/reading_half_a_pointer.rs:LL:CC
    |
 LL |         let _val = *x;
-   |                    ^^ memory access failed: attempting to access 1 byte, but got $HEX[noalloc] which is a dangling pointer (it has no provenance)
+   |                    ^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/shims/backtrace/bad-backtrace-decl.stderr b/src/tools/miri/tests/fail/shims/backtrace/bad-backtrace-decl.stderr
index 346cc77df1b..266e941436d 100644
--- a/src/tools/miri/tests/fail/shims/backtrace/bad-backtrace-decl.stderr
+++ b/src/tools/miri/tests/fail/shims/backtrace/bad-backtrace-decl.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: bad declaration of miri_resolve_frame - should return
   --> tests/fail/shims/backtrace/bad-backtrace-decl.rs:LL:CC
    |
 LL | ...   miri_resolve_frame(*frame, 0);
-   |       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ bad declaration of miri_resolve_frame - should return a struct with 5 fields
+   |       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/shims/backtrace/bad-backtrace-flags.stderr b/src/tools/miri/tests/fail/shims/backtrace/bad-backtrace-flags.stderr
index a8d531c5123..dd2b1900321 100644
--- a/src/tools/miri/tests/fail/shims/backtrace/bad-backtrace-flags.stderr
+++ b/src/tools/miri/tests/fail/shims/backtrace/bad-backtrace-flags.stderr
@@ -2,7 +2,7 @@ error: unsupported operation: unknown `miri_get_backtrace` flags 2
   --> tests/fail/shims/backtrace/bad-backtrace-flags.rs:LL:CC
    |
 LL |         miri_get_backtrace(2, std::ptr::null_mut());
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ unknown `miri_get_backtrace` flags 2
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ unsupported operation occurred here
    |
    = help: this is likely not a bug in the program; it indicates that the program performed an operation that Miri does not support
    = note: BACKTRACE:
diff --git a/src/tools/miri/tests/fail/shims/backtrace/bad-backtrace-ptr.stderr b/src/tools/miri/tests/fail/shims/backtrace/bad-backtrace-ptr.stderr
index 126f41fbb0e..2274b1098aa 100644
--- a/src/tools/miri/tests/fail/shims/backtrace/bad-backtrace-ptr.stderr
+++ b/src/tools/miri/tests/fail/shims/backtrace/bad-backtrace-ptr.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: pointer not dereferenceable: pointer must point to so
   --> tests/fail/shims/backtrace/bad-backtrace-ptr.rs:LL:CC
    |
 LL |         miri_resolve_frame(std::ptr::null_mut(), 0);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ pointer not dereferenceable: pointer must point to some allocation, but got null pointer
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/shims/backtrace/bad-backtrace-resolve-flags.stderr b/src/tools/miri/tests/fail/shims/backtrace/bad-backtrace-resolve-flags.stderr
index d79ae1ec414..ba9ea5ce3a4 100644
--- a/src/tools/miri/tests/fail/shims/backtrace/bad-backtrace-resolve-flags.stderr
+++ b/src/tools/miri/tests/fail/shims/backtrace/bad-backtrace-resolve-flags.stderr
@@ -2,7 +2,7 @@ error: unsupported operation: unknown `miri_resolve_frame` flags 2
   --> tests/fail/shims/backtrace/bad-backtrace-resolve-flags.rs:LL:CC
    |
 LL |         miri_resolve_frame(buf[0], 2);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ unknown `miri_resolve_frame` flags 2
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ unsupported operation occurred here
    |
    = help: this is likely not a bug in the program; it indicates that the program performed an operation that Miri does not support
    = note: BACKTRACE:
diff --git a/src/tools/miri/tests/fail/shims/backtrace/bad-backtrace-resolve-names-flags.stderr b/src/tools/miri/tests/fail/shims/backtrace/bad-backtrace-resolve-names-flags.stderr
index ff3176a789b..e0498586a03 100644
--- a/src/tools/miri/tests/fail/shims/backtrace/bad-backtrace-resolve-names-flags.stderr
+++ b/src/tools/miri/tests/fail/shims/backtrace/bad-backtrace-resolve-names-flags.stderr
@@ -2,7 +2,7 @@ error: unsupported operation: unknown `miri_resolve_frame_names` flags 2
   --> tests/fail/shims/backtrace/bad-backtrace-resolve-names-flags.rs:LL:CC
    |
 LL | ...   miri_resolve_frame_names(buf[0], 2, std::ptr::null_mut(), std::ptr::null_mut());
-   |       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ unknown `miri_resolve_frame_names` flags 2
+   |       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ unsupported operation occurred here
    |
    = help: this is likely not a bug in the program; it indicates that the program performed an operation that Miri does not support
    = note: BACKTRACE:
diff --git a/src/tools/miri/tests/fail/shims/backtrace/bad-backtrace-size-flags.stderr b/src/tools/miri/tests/fail/shims/backtrace/bad-backtrace-size-flags.stderr
index da287e564e3..5846fbb769f 100644
--- a/src/tools/miri/tests/fail/shims/backtrace/bad-backtrace-size-flags.stderr
+++ b/src/tools/miri/tests/fail/shims/backtrace/bad-backtrace-size-flags.stderr
@@ -2,7 +2,7 @@ error: unsupported operation: unknown `miri_backtrace_size` flags 2
   --> tests/fail/shims/backtrace/bad-backtrace-size-flags.rs:LL:CC
    |
 LL |         miri_backtrace_size(2);
-   |         ^^^^^^^^^^^^^^^^^^^^^^ unknown `miri_backtrace_size` flags 2
+   |         ^^^^^^^^^^^^^^^^^^^^^^ unsupported operation occurred here
    |
    = help: this is likely not a bug in the program; it indicates that the program performed an operation that Miri does not support
    = note: BACKTRACE:
diff --git a/src/tools/miri/tests/fail/shims/fs/isolated_file.stderr b/src/tools/miri/tests/fail/shims/fs/isolated_file.stderr
index 75167ab5b38..f08909d4427 100644
--- a/src/tools/miri/tests/fail/shims/fs/isolated_file.stderr
+++ b/src/tools/miri/tests/fail/shims/fs/isolated_file.stderr
@@ -2,7 +2,7 @@ error: unsupported operation: `open` not available when isolation is enabled
   --> RUSTLIB/std/src/sys/fs/PLATFORM.rs:LL:CC
    |
 LL |         let fd = cvt_r(|| unsafe { open64(path.as_ptr(), flags, opts.mode as c_int) })?;
-   |                                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `open` not available when isolation is enabled
+   |                                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ unsupported operation occurred here
    |
    = help: set `MIRIFLAGS=-Zmiri-disable-isolation` to disable isolation;
    = help: or set `MIRIFLAGS=-Zmiri-isolation-error=warn` to make Miri return an error code from isolated operations (if supported for that operation) and continue with a warning
diff --git a/src/tools/miri/tests/fail/shims/input_arg_mismatch.stderr b/src/tools/miri/tests/fail/shims/input_arg_mismatch.stderr
index 90d4ce78ad4..ce00b624a42 100644
--- a/src/tools/miri/tests/fail/shims/input_arg_mismatch.stderr
+++ b/src/tools/miri/tests/fail/shims/input_arg_mismatch.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: calling a function with argument of type i32 passing
   --> tests/fail/shims/input_arg_mismatch.rs:LL:CC
    |
 LL |         close(fd);
-   |         ^^^^^^^^^ calling a function with argument of type i32 passing data of type u32
+   |         ^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/shims/isolated_stdin.stderr b/src/tools/miri/tests/fail/shims/isolated_stdin.stderr
index 1a4d7e96329..5fda90b46ef 100644
--- a/src/tools/miri/tests/fail/shims/isolated_stdin.stderr
+++ b/src/tools/miri/tests/fail/shims/isolated_stdin.stderr
@@ -1,7 +1,7 @@
 error: unsupported operation: `read` from stdin not available when isolation is enabled
   --> RUSTLIB/std/$FILE:LL:CC
    |
-   | ^ `read` from stdin not available when isolation is enabled
+   | ^ unsupported operation occurred here
    |
    = help: set `MIRIFLAGS=-Zmiri-disable-isolation` to disable isolation;
    = help: or set `MIRIFLAGS=-Zmiri-isolation-error=warn` to make Miri return an error code from isolated operations (if supported for that operation) and continue with a warning
diff --git a/src/tools/miri/tests/fail/shims/non_vararg_signature_mismatch.stderr b/src/tools/miri/tests/fail/shims/non_vararg_signature_mismatch.stderr
index 43813af9a3c..e01ba235f89 100644
--- a/src/tools/miri/tests/fail/shims/non_vararg_signature_mismatch.stderr
+++ b/src/tools/miri/tests/fail/shims/non_vararg_signature_mismatch.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: calling a variadic function with a non-variadic calle
   --> tests/fail/shims/non_vararg_signature_mismatch.rs:LL:CC
    |
 LL |         open(c_path.as_ptr(), /* value does not matter */ 0)
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ calling a variadic function with a non-variadic caller-side signature
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/shims/return_type_mismatch.stderr b/src/tools/miri/tests/fail/shims/return_type_mismatch.stderr
index 062aa7b4927..18ff3067fa0 100644
--- a/src/tools/miri/tests/fail/shims/return_type_mismatch.stderr
+++ b/src/tools/miri/tests/fail/shims/return_type_mismatch.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: calling a function with return type i32 passing retur
   --> tests/fail/shims/return_type_mismatch.rs:LL:CC
    |
 LL |         close(fd);
-   |         ^^^^^^^^^ calling a function with return type i32 passing return place of type i16
+   |         ^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/shims/shim_arg_size.stderr b/src/tools/miri/tests/fail/shims/shim_arg_size.stderr
index e17fe9019ff..688272df263 100644
--- a/src/tools/miri/tests/fail/shims/shim_arg_size.stderr
+++ b/src/tools/miri/tests/fail/shims/shim_arg_size.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: scalar size mismatch: expected 4 bytes but got 1 byte
   --> tests/fail/shims/shim_arg_size.rs:LL:CC
    |
 LL |         memchr(std::ptr::null(), 0, 0);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ scalar size mismatch: expected 4 bytes but got 1 bytes instead
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/shims/vararg_caller_signature_mismatch.stderr b/src/tools/miri/tests/fail/shims/vararg_caller_signature_mismatch.stderr
index 0f642aca322..a7b8be9b36d 100644
--- a/src/tools/miri/tests/fail/shims/vararg_caller_signature_mismatch.stderr
+++ b/src/tools/miri/tests/fail/shims/vararg_caller_signature_mismatch.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: ABI mismatch: calling a non-variadic function with a
   --> tests/fail/shims/vararg_caller_signature_mismatch.rs:LL:CC
    |
 LL |     let res = unsafe { pipe(fds.as_mut_ptr()) };
-   |                        ^^^^^^^^^^^^^^^^^^^^^^ ABI mismatch: calling a non-variadic function with a variadic caller-side signature
+   |                        ^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/shims/wrong_fixed_arg_count.stderr b/src/tools/miri/tests/fail/shims/wrong_fixed_arg_count.stderr
index 12e464813cf..fcec61a9e7e 100644
--- a/src/tools/miri/tests/fail/shims/wrong_fixed_arg_count.stderr
+++ b/src/tools/miri/tests/fail/shims/wrong_fixed_arg_count.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: incorrect number of fixed arguments for variadic func
   --> tests/fail/shims/wrong_fixed_arg_count.rs:LL:CC
    |
 LL |         open(c_path.as_ptr(), /* value does not matter */ 0)
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ incorrect number of fixed arguments for variadic function `open`: got 1, expected 2
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/stacked_borrows/deallocate_against_protector1.stderr b/src/tools/miri/tests/fail/stacked_borrows/deallocate_against_protector1.stderr
index f4cfa49c156..8d18e5a7d60 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/deallocate_against_protector1.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/deallocate_against_protector1.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: deallocating while item [Unique for <TAG>] is strongl
   --> RUSTLIB/alloc/src/boxed.rs:LL:CC
    |
 LL |                 self.1.deallocate(From::from(ptr.cast()), layout);
-   |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ deallocating while item [Unique for <TAG>] is strongly protected
+   |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/stacked_borrows/disable_mut_does_not_merge_srw.stderr b/src/tools/miri/tests/fail/stacked_borrows/disable_mut_does_not_merge_srw.stderr
index 2d0209d1a2a..7e9fb3f3c88 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/disable_mut_does_not_merge_srw.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/disable_mut_does_not_merge_srw.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: attempting a read access using <TAG> at ALLOC[0x0], b
   --> tests/fail/stacked_borrows/disable_mut_does_not_merge_srw.rs:LL:CC
    |
 LL |         let _val = *raw;
-   |                    ^^^^
-   |                    |
-   |                    attempting a read access using <TAG> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
-   |                    this error occurs as part of an access at ALLOC[0x0..0x4]
+   |                    ^^^^ this error occurs as part of an access at ALLOC[0x0..0x4]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/stacked_borrows/drop_in_place_protector.stderr b/src/tools/miri/tests/fail/stacked_borrows/drop_in_place_protector.stderr
index f107ea2023d..464c44802ec 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/drop_in_place_protector.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/drop_in_place_protector.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: not granting access to tag <TAG> because that would r
   --> tests/fail/stacked_borrows/drop_in_place_protector.rs:LL:CC
    |
 LL |             let _val = *P;
-   |                        ^^ not granting access to tag <TAG> because that would remove [Unique for <TAG>] which is strongly protected
+   |                        ^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/stacked_borrows/drop_in_place_retag.stderr b/src/tools/miri/tests/fail/stacked_borrows/drop_in_place_retag.stderr
index eebedf842ef..ec578db2d0a 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/drop_in_place_retag.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/drop_in_place_retag.stderr
@@ -1,11 +1,8 @@
 error: Undefined Behavior: trying to retag from <TAG> for Unique permission at ALLOC[0x0], but that tag only grants SharedReadOnly permission for this location
   --> RUSTLIB/core/src/ptr/mod.rs:LL:CC
    |
-LL | pub unsafe fn drop_in_place<T: ?Sized>(to_drop: *mut T) {
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   | |
-   | trying to retag from <TAG> for Unique permission at ALLOC[0x0], but that tag only grants SharedReadOnly permission for this location
-   | this error occurs as part of retag at ALLOC[0x0..0x1]
+LL | pub unsafe fn drop_in_place<T: PointeeSized>(to_drop: *mut T) {
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ this error occurs as part of retag at ALLOC[0x0..0x1]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/stacked_borrows/exposed_only_ro.stderr b/src/tools/miri/tests/fail/stacked_borrows/exposed_only_ro.stderr
index 861dd75bb22..07662573f61 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/exposed_only_ro.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/exposed_only_ro.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: attempting a write access using <wildcard> at ALLOC[0
   --> tests/fail/stacked_borrows/exposed_only_ro.rs:LL:CC
    |
 LL |     unsafe { *ptr = 0 };
-   |              ^^^^^^^^
-   |              |
-   |              attempting a write access using <wildcard> at ALLOC[0x0], but no exposed tags have suitable permission in the borrow stack for this location
-   |              this error occurs as part of an access at ALLOC[0x0..0x4]
+   |              ^^^^^^^^ this error occurs as part of an access at ALLOC[0x0..0x4]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/stacked_borrows/fnentry_invalidation.stderr b/src/tools/miri/tests/fail/stacked_borrows/fnentry_invalidation.stderr
index 1a71feee7a1..b4f82469a8b 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/fnentry_invalidation.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/fnentry_invalidation.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: attempting a read access using <TAG> at ALLOC[0x0], b
   --> tests/fail/stacked_borrows/fnentry_invalidation.rs:LL:CC
    |
 LL |         let _oof = *z;
-   |                    ^^
-   |                    |
-   |                    attempting a read access using <TAG> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
-   |                    this error occurs as part of an access at ALLOC[0x0..0x4]
+   |                    ^^ this error occurs as part of an access at ALLOC[0x0..0x4]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/stacked_borrows/fnentry_invalidation2.stderr b/src/tools/miri/tests/fail/stacked_borrows/fnentry_invalidation2.stderr
index 0b5b005881e..ad24e0fa32d 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/fnentry_invalidation2.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/fnentry_invalidation2.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: attempting a read access using <TAG> at ALLOC[0x0], b
   --> tests/fail/stacked_borrows/fnentry_invalidation2.rs:LL:CC
    |
 LL |         let _oof = *ptr;
-   |                    ^^^^
-   |                    |
-   |                    attempting a read access using <TAG> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
-   |                    this error occurs as part of an access at ALLOC[0x0..0x4]
+   |                    ^^^^ this error occurs as part of an access at ALLOC[0x0..0x4]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/stacked_borrows/illegal_dealloc1.stderr b/src/tools/miri/tests/fail/stacked_borrows/illegal_dealloc1.stderr
index ddf8dbea31f..4e547e567e8 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/illegal_dealloc1.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/illegal_dealloc1.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: attempting deallocation using <TAG> at ALLOC, but tha
   --> tests/fail/stacked_borrows/illegal_deALLOC.rs:LL:CC
    |
 LL |         dealloc(ptr2, Layout::from_size_align_unchecked(1, 1));
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ attempting deallocation using <TAG> at ALLOC, but that tag does not exist in the borrow stack for this location
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/stacked_borrows/illegal_read1.stderr b/src/tools/miri/tests/fail/stacked_borrows/illegal_read1.stderr
index bc719f9f205..ea9dc47460a 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/illegal_read1.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/illegal_read1.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: attempting a read access using <TAG> at ALLOC[0x0], b
   --> tests/fail/stacked_borrows/illegal_read1.rs:LL:CC
    |
 LL |     let _val = *xref; // ...but any use of raw will invalidate our ref.
-   |                ^^^^^
-   |                |
-   |                attempting a read access using <TAG> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
-   |                this error occurs as part of an access at ALLOC[0x0..0x4]
+   |                ^^^^^ this error occurs as part of an access at ALLOC[0x0..0x4]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/stacked_borrows/illegal_read2.stderr b/src/tools/miri/tests/fail/stacked_borrows/illegal_read2.stderr
index d1bca88d05b..fec08275f10 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/illegal_read2.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/illegal_read2.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: attempting a read access using <TAG> at ALLOC[0x0], b
   --> tests/fail/stacked_borrows/illegal_read2.rs:LL:CC
    |
 LL |     let _val = *xref; // ...but any use of raw will invalidate our ref.
-   |                ^^^^^
-   |                |
-   |                attempting a read access using <TAG> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
-   |                this error occurs as part of an access at ALLOC[0x0..0x4]
+   |                ^^^^^ this error occurs as part of an access at ALLOC[0x0..0x4]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/stacked_borrows/illegal_read3.stderr b/src/tools/miri/tests/fail/stacked_borrows/illegal_read3.stderr
index 6a6701aae19..2ef951a6e9c 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/illegal_read3.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/illegal_read3.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: attempting a read access using <TAG> at ALLOC[0x0], b
   --> tests/fail/stacked_borrows/illegal_read3.rs:LL:CC
    |
 LL |     let _val = *xref2;
-   |                ^^^^^^
-   |                |
-   |                attempting a read access using <TAG> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
-   |                this error occurs as part of an access at ALLOC[0x0..0x4]
+   |                ^^^^^^ this error occurs as part of an access at ALLOC[0x0..0x4]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/stacked_borrows/illegal_read4.stderr b/src/tools/miri/tests/fail/stacked_borrows/illegal_read4.stderr
index 0d460df3929..fdf5ae4297a 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/illegal_read4.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/illegal_read4.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: attempting a read access using <TAG> at ALLOC[0x0], b
   --> tests/fail/stacked_borrows/illegal_read4.rs:LL:CC
    |
 LL |     let _illegal = *xref2;
-   |                    ^^^^^^
-   |                    |
-   |                    attempting a read access using <TAG> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
-   |                    this error occurs as part of an access at ALLOC[0x0..0x4]
+   |                    ^^^^^^ this error occurs as part of an access at ALLOC[0x0..0x4]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/stacked_borrows/illegal_read5.stderr b/src/tools/miri/tests/fail/stacked_borrows/illegal_read5.stderr
index 9862d8a1a34..f1514cf4906 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/illegal_read5.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/illegal_read5.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: attempting a read access using <TAG> at ALLOC[$HEX],
   --> tests/fail/stacked_borrows/illegal_read5.rs:LL:CC
    |
 LL |     let _val = *xref; // the mutable one is dead and gone
-   |                ^^^^^
-   |                |
-   |                attempting a read access using <TAG> at ALLOC[$HEX], but that tag does not exist in the borrow stack for this location
-   |                this error occurs as part of an access at ALLOC[$HEX..$HEX]
+   |                ^^^^^ this error occurs as part of an access at ALLOC[$HEX..$HEX]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/stacked_borrows/illegal_read6.stderr b/src/tools/miri/tests/fail/stacked_borrows/illegal_read6.stderr
index 31c5ad160a9..3deb458cf22 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/illegal_read6.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/illegal_read6.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: attempting a read access using <TAG> at ALLOC[0x0], b
   --> tests/fail/stacked_borrows/illegal_read6.rs:LL:CC
    |
 LL |         let _val = *raw;
-   |                    ^^^^
-   |                    |
-   |                    attempting a read access using <TAG> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
-   |                    this error occurs as part of an access at ALLOC[0x0..0x4]
+   |                    ^^^^ this error occurs as part of an access at ALLOC[0x0..0x4]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/stacked_borrows/illegal_read7.stderr b/src/tools/miri/tests/fail/stacked_borrows/illegal_read7.stderr
index 4ae41dd8ee6..0ed58cf775b 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/illegal_read7.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/illegal_read7.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: trying to retag from <TAG> for SharedReadWrite permis
   --> tests/fail/stacked_borrows/illegal_read7.rs:LL:CC
    |
 LL |         let _val = *x.get_mut();
-   |                     ^
-   |                     |
-   |                     trying to retag from <TAG> for SharedReadWrite permission at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
-   |                     this error occurs as part of two-phase retag at ALLOC[0x0..0x4]
+   |                     ^ this error occurs as part of two-phase retag at ALLOC[0x0..0x4]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/stacked_borrows/illegal_read8.stderr b/src/tools/miri/tests/fail/stacked_borrows/illegal_read8.stderr
index fc07c3174ba..7eb52d7ec3b 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/illegal_read8.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/illegal_read8.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: attempting a read access using <TAG> at ALLOC[0x0], b
   --> tests/fail/stacked_borrows/illegal_read8.rs:LL:CC
    |
 LL |         let _fail = *y1;
-   |                     ^^^
-   |                     |
-   |                     attempting a read access using <TAG> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
-   |                     this error occurs as part of an access at ALLOC[0x0..0x4]
+   |                     ^^^ this error occurs as part of an access at ALLOC[0x0..0x4]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/stacked_borrows/illegal_read_despite_exposed1.stderr b/src/tools/miri/tests/fail/stacked_borrows/illegal_read_despite_exposed1.stderr
index 18a47bb3462..3c6dbf7fdce 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/illegal_read_despite_exposed1.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/illegal_read_despite_exposed1.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: attempting a read access using <TAG> at ALLOC[0x0], b
   --> tests/fail/stacked_borrows/illegal_read_despite_exposed1.rs:LL:CC
    |
 LL |         let _val = *root2;
-   |                    ^^^^^^
-   |                    |
-   |                    attempting a read access using <TAG> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
-   |                    this error occurs as part of an access at ALLOC[0x0..0x4]
+   |                    ^^^^^^ this error occurs as part of an access at ALLOC[0x0..0x4]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/stacked_borrows/illegal_read_despite_exposed2.stderr b/src/tools/miri/tests/fail/stacked_borrows/illegal_read_despite_exposed2.stderr
index 245bce19938..630fbd2fd14 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/illegal_read_despite_exposed2.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/illegal_read_despite_exposed2.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: attempting a read access using <TAG> at ALLOC[0x0], b
   --> tests/fail/stacked_borrows/illegal_read_despite_exposed2.rs:LL:CC
    |
 LL |         let _val = *root2;
-   |                    ^^^^^^
-   |                    |
-   |                    attempting a read access using <TAG> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
-   |                    this error occurs as part of an access at ALLOC[0x0..0x4]
+   |                    ^^^^^^ this error occurs as part of an access at ALLOC[0x0..0x4]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/stacked_borrows/illegal_write2.stderr b/src/tools/miri/tests/fail/stacked_borrows/illegal_write2.stderr
index 595d0ca7588..684e4ef1946 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/illegal_write2.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/illegal_write2.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: attempting a write access using <TAG> at ALLOC[0x0],
   --> tests/fail/stacked_borrows/illegal_write2.rs:LL:CC
    |
 LL |     unsafe { *target2 = 13 };
-   |              ^^^^^^^^^^^^^
-   |              |
-   |              attempting a write access using <TAG> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
-   |              this error occurs as part of an access at ALLOC[0x0..0x4]
+   |              ^^^^^^^^^^^^^ this error occurs as part of an access at ALLOC[0x0..0x4]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/stacked_borrows/illegal_write3.stderr b/src/tools/miri/tests/fail/stacked_borrows/illegal_write3.stderr
index 6805b359367..431dc4443d2 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/illegal_write3.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/illegal_write3.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: attempting a write access using <TAG> at ALLOC[0x0],
   --> tests/fail/stacked_borrows/illegal_write3.rs:LL:CC
    |
 LL |     unsafe { *ptr = 42 };
-   |              ^^^^^^^^^
-   |              |
-   |              attempting a write access using <TAG> at ALLOC[0x0], but that tag only grants SharedReadOnly permission for this location
-   |              this error occurs as part of an access at ALLOC[0x0..0x4]
+   |              ^^^^^^^^^ this error occurs as part of an access at ALLOC[0x0..0x4]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/stacked_borrows/illegal_write4.stderr b/src/tools/miri/tests/fail/stacked_borrows/illegal_write4.stderr
index 0134987caf3..954deeee77d 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/illegal_write4.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/illegal_write4.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: attempting a read access using <TAG> at ALLOC[0x0], b
   --> tests/fail/stacked_borrows/illegal_write4.rs:LL:CC
    |
 LL |     let _val = *reference;
-   |                ^^^^^^^^^^
-   |                |
-   |                attempting a read access using <TAG> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
-   |                this error occurs as part of an access at ALLOC[0x0..0x4]
+   |                ^^^^^^^^^^ this error occurs as part of an access at ALLOC[0x0..0x4]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/stacked_borrows/illegal_write_despite_exposed1.stderr b/src/tools/miri/tests/fail/stacked_borrows/illegal_write_despite_exposed1.stderr
index 42e088dc075..03597105e8e 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/illegal_write_despite_exposed1.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/illegal_write_despite_exposed1.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: attempting a read access using <TAG> at ALLOC[0x0], b
   --> tests/fail/stacked_borrows/illegal_write_despite_exposed1.rs:LL:CC
    |
 LL |         let _val = *root2;
-   |                    ^^^^^^
-   |                    |
-   |                    attempting a read access using <TAG> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
-   |                    this error occurs as part of an access at ALLOC[0x0..0x4]
+   |                    ^^^^^^ this error occurs as part of an access at ALLOC[0x0..0x4]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/stacked_borrows/interior_mut1.stderr b/src/tools/miri/tests/fail/stacked_borrows/interior_mut1.stderr
index 3d43bf7e6bf..76a320a819a 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/interior_mut1.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/interior_mut1.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: trying to retag from <TAG> for SharedReadWrite permis
   --> tests/fail/stacked_borrows/interior_mut1.rs:LL:CC
    |
 LL |         let _val = *inner_shr.get();
-   |                     ^^^^^^^^^
-   |                     |
-   |                     trying to retag from <TAG> for SharedReadWrite permission at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
-   |                     this error occurs as part of retag at ALLOC[0x0..0x4]
+   |                     ^^^^^^^^^ this error occurs as part of retag at ALLOC[0x0..0x4]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/stacked_borrows/interior_mut2.stderr b/src/tools/miri/tests/fail/stacked_borrows/interior_mut2.stderr
index a7a1521bd63..c7852d58b8e 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/interior_mut2.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/interior_mut2.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: trying to retag from <TAG> for SharedReadWrite permis
   --> tests/fail/stacked_borrows/interior_mut2.rs:LL:CC
    |
 LL |         let _val = *inner_shr.get();
-   |                     ^^^^^^^^^
-   |                     |
-   |                     trying to retag from <TAG> for SharedReadWrite permission at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
-   |                     this error occurs as part of retag at ALLOC[0x0..0x4]
+   |                     ^^^^^^^^^ this error occurs as part of retag at ALLOC[0x0..0x4]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/stacked_borrows/invalidate_against_protector1.stderr b/src/tools/miri/tests/fail/stacked_borrows/invalidate_against_protector1.stderr
index 5956a3f6753..b082abe7b25 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/invalidate_against_protector1.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/invalidate_against_protector1.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: not granting access to tag <TAG> because that would r
   --> tests/fail/stacked_borrows/invalidate_against_protector1.rs:LL:CC
    |
 LL |     let _val = unsafe { *x };
-   |                         ^^ not granting access to tag <TAG> because that would remove [Unique for <TAG>] which is strongly protected
+   |                         ^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/stacked_borrows/load_invalid_mut.stderr b/src/tools/miri/tests/fail/stacked_borrows/load_invalid_mut.stderr
index 733162acff7..ff295c4bf84 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/load_invalid_mut.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/load_invalid_mut.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: trying to retag from <TAG> for Unique permission at A
   --> tests/fail/stacked_borrows/load_invalid_mut.rs:LL:CC
    |
 LL |     let _val = *xref_in_mem;
-   |                ^^^^^^^^^^^^
-   |                |
-   |                trying to retag from <TAG> for Unique permission at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
-   |                this error occurs as part of retag at ALLOC[0x0..0x4]
+   |                ^^^^^^^^^^^^ this error occurs as part of retag at ALLOC[0x0..0x4]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/stacked_borrows/pass_invalid_mut.stderr b/src/tools/miri/tests/fail/stacked_borrows/pass_invalid_mut.stderr
index c910a05de1c..382343f18db 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/pass_invalid_mut.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/pass_invalid_mut.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: trying to retag from <TAG> for SharedReadWrite permis
   --> tests/fail/stacked_borrows/pass_invalid_mut.rs:LL:CC
    |
 LL |     foo(xref);
-   |         ^^^^
-   |         |
-   |         trying to retag from <TAG> for SharedReadWrite permission at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
-   |         this error occurs as part of two-phase retag at ALLOC[0x0..0x4]
+   |         ^^^^ this error occurs as part of two-phase retag at ALLOC[0x0..0x4]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/stacked_borrows/pointer_smuggling.stderr b/src/tools/miri/tests/fail/stacked_borrows/pointer_smuggling.stderr
index 58c6cd4c318..b07599a500e 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/pointer_smuggling.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/pointer_smuggling.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: attempting a read access using <TAG> at ALLOC[0x0], b
   --> tests/fail/stacked_borrows/pointer_smuggling.rs:LL:CC
    |
 LL |     let _x = unsafe { *PTR };
-   |                       ^^^^
-   |                       |
-   |                       attempting a read access using <TAG> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
-   |                       this error occurs as part of an access at ALLOC[0x0..0x1]
+   |                       ^^^^ this error occurs as part of an access at ALLOC[0x0..0x1]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/stacked_borrows/raw_tracking.stderr b/src/tools/miri/tests/fail/stacked_borrows/raw_tracking.stderr
index aa320ea908c..479bc87e99c 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/raw_tracking.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/raw_tracking.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: attempting a write access using <TAG> at ALLOC[0x0],
   --> tests/fail/stacked_borrows/raw_tracking.rs:LL:CC
    |
 LL |     unsafe { *raw1 = 13 };
-   |              ^^^^^^^^^^
-   |              |
-   |              attempting a write access using <TAG> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
-   |              this error occurs as part of an access at ALLOC[0x0..0x4]
+   |              ^^^^^^^^^^ this error occurs as part of an access at ALLOC[0x0..0x4]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/stacked_borrows/retag_data_race_protected_read.stderr b/src/tools/miri/tests/fail/stacked_borrows/retag_data_race_protected_read.stderr
index fd5d83211db..561ce3164c3 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/retag_data_race_protected_read.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/retag_data_race_protected_read.stderr
@@ -1,8 +1,8 @@
-error: Undefined Behavior: Data race detected between (1) non-atomic read on thread `main` and (2) retag write of type `i32` on thread `unnamed-ID` at ALLOC. (2) just happened here
+error: Undefined Behavior: Data race detected between (1) non-atomic read on thread `main` and (2) retag write of type `i32` on thread `unnamed-ID` at ALLOC
   --> tests/fail/stacked_borrows/retag_data_race_protected_read.rs:LL:CC
    |
-LL |         retag(unsafe { &mut *ptr.0 });
-   |                        ^^^^^^^^^^^ Data race detected between (1) non-atomic read on thread `main` and (2) retag write of type `i32` on thread `unnamed-ID` at ALLOC. (2) just happened here
+LL | ...   retag(unsafe { &mut *ptr.0 });
+   |                      ^^^^^^^^^^^ (2) just happened here
    |
 help: and (1) occurred earlier here
   --> tests/fail/stacked_borrows/retag_data_race_protected_read.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/stacked_borrows/retag_data_race_read.stderr b/src/tools/miri/tests/fail/stacked_borrows/retag_data_race_read.stderr
index 87155ebc518..d84fbc76056 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/retag_data_race_read.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/retag_data_race_read.stderr
@@ -1,8 +1,8 @@
-error: Undefined Behavior: Data race detected between (1) retag read on thread `unnamed-ID` and (2) non-atomic write on thread `unnamed-ID` at ALLOC. (2) just happened here
+error: Undefined Behavior: Data race detected between (1) retag read on thread `unnamed-ID` and (2) non-atomic write on thread `unnamed-ID` at ALLOC
   --> tests/fail/stacked_borrows/retag_data_race_read.rs:LL:CC
    |
 LL |         *p = 5;
-   |         ^^^^^^ Data race detected between (1) retag read on thread `unnamed-ID` and (2) non-atomic write on thread `unnamed-ID` at ALLOC. (2) just happened here
+   |         ^^^^^^ (2) just happened here
    |
 help: and (1) occurred earlier here
   --> tests/fail/stacked_borrows/retag_data_race_read.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/stacked_borrows/return_invalid_mut.stderr b/src/tools/miri/tests/fail/stacked_borrows/return_invalid_mut.stderr
index 760ed783175..4ac82192a9f 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/return_invalid_mut.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/return_invalid_mut.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: trying to retag from <TAG> for Unique permission at A
   --> tests/fail/stacked_borrows/return_invalid_mut.rs:LL:CC
    |
 LL |     ret
-   |     ^^^
-   |     |
-   |     trying to retag from <TAG> for Unique permission at ALLOC[0x4], but that tag does not exist in the borrow stack for this location
-   |     this error occurs as part of retag at ALLOC[0x4..0x8]
+   |     ^^^ this error occurs as part of retag at ALLOC[0x4..0x8]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/stacked_borrows/return_invalid_mut_option.stderr b/src/tools/miri/tests/fail/stacked_borrows/return_invalid_mut_option.stderr
index 3175e099620..7e7670e49f1 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/return_invalid_mut_option.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/return_invalid_mut_option.stderr
@@ -4,7 +4,6 @@ error: Undefined Behavior: trying to retag from <TAG> for Unique permission at A
 LL |     ret
    |     ^^^
    |     |
-   |     trying to retag from <TAG> for Unique permission at ALLOC[0x4], but that tag does not exist in the borrow stack for this location
    |     this error occurs as part of retag (of a reference/box inside this compound value) at ALLOC[0x4..0x8]
    |     errors for retagging in fields are fairly new; please reach out to us (e.g. at <https://rust-lang.zulipchat.com/#narrow/stream/269128-miri>) if you find this error troubling
    |
diff --git a/src/tools/miri/tests/fail/stacked_borrows/return_invalid_mut_tuple.stderr b/src/tools/miri/tests/fail/stacked_borrows/return_invalid_mut_tuple.stderr
index 2cc3ba2c9a9..aeaa694d292 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/return_invalid_mut_tuple.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/return_invalid_mut_tuple.stderr
@@ -4,7 +4,6 @@ error: Undefined Behavior: trying to retag from <TAG> for Unique permission at A
 LL |     ret
    |     ^^^
    |     |
-   |     trying to retag from <TAG> for Unique permission at ALLOC[0x4], but that tag does not exist in the borrow stack for this location
    |     this error occurs as part of retag (of a reference/box inside this compound value) at ALLOC[0x4..0x8]
    |     errors for retagging in fields are fairly new; please reach out to us (e.g. at <https://rust-lang.zulipchat.com/#narrow/stream/269128-miri>) if you find this error troubling
    |
diff --git a/src/tools/miri/tests/fail/stacked_borrows/shared_rw_borrows_are_weak1.stderr b/src/tools/miri/tests/fail/stacked_borrows/shared_rw_borrows_are_weak1.stderr
index 56d9783367b..ebeb721b76f 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/shared_rw_borrows_are_weak1.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/shared_rw_borrows_are_weak1.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: trying to retag from <TAG> for SharedReadWrite permis
   --> tests/fail/stacked_borrows/shared_rw_borrows_are_weak1.rs:LL:CC
    |
 LL |         y.get_mut();
-   |         ^
-   |         |
-   |         trying to retag from <TAG> for SharedReadWrite permission at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
-   |         this error occurs as part of two-phase retag at ALLOC[0x0..0x4]
+   |         ^ this error occurs as part of two-phase retag at ALLOC[0x0..0x4]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/stacked_borrows/shared_rw_borrows_are_weak2.stderr b/src/tools/miri/tests/fail/stacked_borrows/shared_rw_borrows_are_weak2.stderr
index 8ca56afc121..79a3d391fcc 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/shared_rw_borrows_are_weak2.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/shared_rw_borrows_are_weak2.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: attempting a read access using <TAG> at ALLOC[$HEX],
   --> tests/fail/stacked_borrows/shared_rw_borrows_are_weak2.rs:LL:CC
    |
 LL |         let _val = *y;
-   |                    ^^
-   |                    |
-   |                    attempting a read access using <TAG> at ALLOC[$HEX], but that tag does not exist in the borrow stack for this location
-   |                    this error occurs as part of an access at ALLOC[$HEX..$HEX]
+   |                    ^^ this error occurs as part of an access at ALLOC[$HEX..$HEX]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/stacked_borrows/static_memory_modification.stderr b/src/tools/miri/tests/fail/stacked_borrows/static_memory_modification.stderr
index b86a64623ba..8e517ad05ed 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/static_memory_modification.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/static_memory_modification.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: writing to ALLOC which is read-only
   --> tests/fail/stacked_borrows/static_memory_modification.rs:LL:CC
    |
 LL |         std::mem::transmute::<&usize, &mut usize>(&X)
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ writing to ALLOC which is read-only
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/stacked_borrows/track_caller.stderr b/src/tools/miri/tests/fail/stacked_borrows/track_caller.stderr
index 163ec84281d..6cdaa2913ea 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/track_caller.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/track_caller.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: attempting a read access using <TAG> at ALLOC[0x0], b
   --> tests/fail/stacked_borrows/track_caller.rs:LL:CC
    |
 LL |     let _val = *xref; // ...but any use of raw will invalidate our ref.
-   |                ^^^^^
-   |                |
-   |                attempting a read access using <TAG> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
-   |                this error occurs as part of an access at ALLOC[0x0..0x4]
+   |                ^^^^^ this error occurs as part of an access at ALLOC[0x0..0x4]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/stacked_borrows/transmute-is-no-escape.stderr b/src/tools/miri/tests/fail/stacked_borrows/transmute-is-no-escape.stderr
index becd6681eca..9d454f2c1e6 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/transmute-is-no-escape.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/transmute-is-no-escape.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: attempting a write access using <TAG> at ALLOC[0x0],
   --> tests/fail/stacked_borrows/transmute-is-no-escape.rs:LL:CC
    |
 LL |     unsafe { *raw = 13 };
-   |              ^^^^^^^^^
-   |              |
-   |              attempting a write access using <TAG> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
-   |              this error occurs as part of an access at ALLOC[0x0..0x4]
+   |              ^^^^^^^^^ this error occurs as part of an access at ALLOC[0x0..0x4]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/stacked_borrows/unescaped_local.stderr b/src/tools/miri/tests/fail/stacked_borrows/unescaped_local.stderr
index 08c2cf2099b..0c78dcd7c88 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/unescaped_local.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/unescaped_local.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: attempting a write access using <wildcard> at ALLOC[0
   --> tests/fail/stacked_borrows/unescaped_local.rs:LL:CC
    |
 LL |         *raw = 13;
-   |         ^^^^^^^^^
-   |         |
-   |         attempting a write access using <wildcard> at ALLOC[0x0], but no exposed tags have suitable permission in the borrow stack for this location
-   |         this error occurs as part of an access at ALLOC[0x0..0x4]
+   |         ^^^^^^^^^ this error occurs as part of an access at ALLOC[0x0..0x4]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/stacked_borrows/unescaped_static.stderr b/src/tools/miri/tests/fail/stacked_borrows/unescaped_static.stderr
index fb48edc5ddd..3efd6c32c93 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/unescaped_static.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/unescaped_static.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: attempting a read access using <TAG> at ALLOC[0x1], b
   --> tests/fail/stacked_borrows/unescaped_static.rs:LL:CC
    |
 LL |     let _val = unsafe { *ptr_to_first.add(1) };
-   |                         ^^^^^^^^^^^^^^^^^^^^
-   |                         |
-   |                         attempting a read access using <TAG> at ALLOC[0x1], but that tag does not exist in the borrow stack for this location
-   |                         this error occurs as part of an access at ALLOC[0x1..0x2]
+   |                         ^^^^^^^^^^^^^^^^^^^^ this error occurs as part of an access at ALLOC[0x1..0x2]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/stacked_borrows/zst_slice.stderr b/src/tools/miri/tests/fail/stacked_borrows/zst_slice.stderr
index 01e3c60f0fe..021f87839e8 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/zst_slice.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/zst_slice.stderr
@@ -2,10 +2,7 @@ error: Undefined Behavior: trying to retag from <TAG> for SharedReadOnly permiss
   --> tests/fail/stacked_borrows/zst_slice.rs:LL:CC
    |
 LL |         assert_eq!(*s.as_ptr().add(1), 2);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |         |
-   |         trying to retag from <TAG> for SharedReadOnly permission at ALLOC[0x4], but that tag does not exist in the borrow stack for this location
-   |         this error occurs as part of retag at ALLOC[0x4..0x8]
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ this error occurs as part of retag at ALLOC[0x4..0x8]
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
diff --git a/src/tools/miri/tests/fail/static_memory_modification1.stderr b/src/tools/miri/tests/fail/static_memory_modification1.stderr
index 2b2cd4af3da..d4a2dca3c14 100644
--- a/src/tools/miri/tests/fail/static_memory_modification1.stderr
+++ b/src/tools/miri/tests/fail/static_memory_modification1.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: writing to ALLOC which is read-only
   --> tests/fail/static_memory_modification1.rs:LL:CC
    |
 LL |         *std::mem::transmute::<&usize, &mut usize>(&X) = 6;
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ writing to ALLOC which is read-only
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/static_memory_modification2.stderr b/src/tools/miri/tests/fail/static_memory_modification2.stderr
index 99c7f15d9ff..48483ce7b29 100644
--- a/src/tools/miri/tests/fail/static_memory_modification2.stderr
+++ b/src/tools/miri/tests/fail/static_memory_modification2.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: writing to ALLOC which is read-only
   --> tests/fail/static_memory_modification2.rs:LL:CC
    |
 LL |         transmute::<&[u8], &mut [u8]>(s.as_bytes())[4] = 42;
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ writing to ALLOC which is read-only
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/static_memory_modification3.stderr b/src/tools/miri/tests/fail/static_memory_modification3.stderr
index cb37a2a2dab..a94a600a08a 100644
--- a/src/tools/miri/tests/fail/static_memory_modification3.stderr
+++ b/src/tools/miri/tests/fail/static_memory_modification3.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: writing to ALLOC which is read-only
   --> tests/fail/static_memory_modification3.rs:LL:CC
    |
 LL |         transmute::<&[u8], &mut [u8]>(bs)[4] = 42;
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ writing to ALLOC which is read-only
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/storage-live-dead-var.stderr b/src/tools/miri/tests/fail/storage-live-dead-var.stderr
index f370c284831..d196f616464 100644
--- a/src/tools/miri/tests/fail/storage-live-dead-var.stderr
+++ b/src/tools/miri/tests/fail/storage-live-dead-var.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: accessing a dead local variable
   --> tests/fail/storage-live-dead-var.rs:LL:CC
    |
 LL |             val = 42;
-   |             ^^^^^^^^ accessing a dead local variable
+   |             ^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/storage-live-resets-var.stderr b/src/tools/miri/tests/fail/storage-live-resets-var.stderr
index 099dd3a1f7e..478123501ec 100644
--- a/src/tools/miri/tests/fail/storage-live-resets-var.stderr
+++ b/src/tools/miri/tests/fail/storage-live-resets-var.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value: encountered uninitialized
   --> tests/fail/storage-live-resets-var.rs:LL:CC
    |
 LL |             _val2 = val;
-   |             ^^^^^^^^^^^ constructing invalid value: encountered uninitialized memory, but expected an integer
+   |             ^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/tail_calls/cc-mismatch.stderr b/src/tools/miri/tests/fail/tail_calls/cc-mismatch.stderr
index 589e30d632e..61a57a64116 100644
--- a/src/tools/miri/tests/fail/tail_calls/cc-mismatch.stderr
+++ b/src/tools/miri/tests/fail/tail_calls/cc-mismatch.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: calling a function with calling convention "C" using
   --> RUSTLIB/core/src/ops/function.rs:LL:CC
    |
 LL |     extern "rust-call" fn call_once(self, args: Args) -> Self::Output;
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ calling a function with calling convention "C" using calling convention "Rust"
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/tail_calls/dangling-local-var.stderr b/src/tools/miri/tests/fail/tail_calls/dangling-local-var.stderr
index 15f73c8a9ae..965dd5b399f 100644
--- a/src/tools/miri/tests/fail/tail_calls/dangling-local-var.stderr
+++ b/src/tools/miri/tests/fail/tail_calls/dangling-local-var.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: memory access failed: ALLOC has been freed, so this p
   --> tests/fail/tail_calls/dangling-local-var.rs:LL:CC
    |
 LL |     let _val = unsafe { *x };
-   |                         ^^ memory access failed: ALLOC has been freed, so this pointer is dangling
+   |                         ^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/tail_calls/signature-mismatch-arg.stderr b/src/tools/miri/tests/fail/tail_calls/signature-mismatch-arg.stderr
index db8ab7cb460..fbb0d3d565d 100644
--- a/src/tools/miri/tests/fail/tail_calls/signature-mismatch-arg.stderr
+++ b/src/tools/miri/tests/fail/tail_calls/signature-mismatch-arg.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: calling a function with argument of type i32 passing
   --> tests/fail/tail_calls/signature-mismatch-arg.rs:LL:CC
    |
 LL |     f(0);
-   |     ^^^^ calling a function with argument of type i32 passing data of type u32
+   |     ^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/terminate-terminator.stderr b/src/tools/miri/tests/fail/terminate-terminator.stderr
index d16119a30e6..a0ee75e5dd2 100644
--- a/src/tools/miri/tests/fail/terminate-terminator.stderr
+++ b/src/tools/miri/tests/fail/terminate-terminator.stderr
@@ -14,7 +14,7 @@ error: abnormal termination: the program aborted execution
   --> RUSTLIB/std/src/sys/pal/PLATFORM/mod.rs:LL:CC
    |
 LL | ABORT()
-   | ^ the program aborted execution
+   | ^ abnormal termination occurred here
    |
    = note: BACKTRACE:
    = note: inside `std::sys::pal::PLATFORM::abort_internal` at RUSTLIB/std/src/sys/pal/PLATFORM/mod.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/tls/tls_static_dealloc.stderr b/src/tools/miri/tests/fail/tls/tls_static_dealloc.stderr
index 3a45dbfb583..a1307b7b41a 100644
--- a/src/tools/miri/tests/fail/tls/tls_static_dealloc.stderr
+++ b/src/tools/miri/tests/fail/tls/tls_static_dealloc.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: memory access failed: ALLOC has been freed, so this p
   --> tests/fail/tls/tls_static_dealloc.rs:LL:CC
    |
 LL |         let _val = *dangling_ptr.0;
-   |                    ^^^^^^^^^^^^^^^ memory access failed: ALLOC has been freed, so this pointer is dangling
+   |                    ^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/tree_borrows/alternate-read-write.stderr b/src/tools/miri/tests/fail/tree_borrows/alternate-read-write.stderr
index 1294b52c051..63c6287f20d 100644
--- a/src/tools/miri/tests/fail/tree_borrows/alternate-read-write.stderr
+++ b/src/tools/miri/tests/fail/tree_borrows/alternate-read-write.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: write access through <TAG> at ALLOC[0x0] is forbidden
   --> tests/fail/tree_borrows/alternate-read-write.rs:LL:CC
    |
 LL |     *y += 1; // Failure
-   |     ^^^^^^^ write access through <TAG> at ALLOC[0x0] is forbidden
+   |     ^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> has state Frozen which forbids this child write access
diff --git a/src/tools/miri/tests/fail/tree_borrows/cell-inside-struct.stderr b/src/tools/miri/tests/fail/tree_borrows/cell-inside-struct.stderr
index 717f1419452..81d5aba6b2e 100644
--- a/src/tools/miri/tests/fail/tree_borrows/cell-inside-struct.stderr
+++ b/src/tools/miri/tests/fail/tree_borrows/cell-inside-struct.stderr
@@ -8,7 +8,7 @@ error: Undefined Behavior: write access through <TAG> (a) at ALLOC[0x0] is forbi
   --> tests/fail/tree_borrows/cell-inside-struct.rs:LL:CC
    |
 LL |         (*a).field1 = 88;
-   |         ^^^^^^^^^^^^^^^^ write access through <TAG> (a) at ALLOC[0x0] is forbidden
+   |         ^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> (a) has state Frozen which forbids this child write access
diff --git a/src/tools/miri/tests/fail/tree_borrows/error-range.stderr b/src/tools/miri/tests/fail/tree_borrows/error-range.stderr
index dc4d7c1f7ff..9a52f68d9b6 100644
--- a/src/tools/miri/tests/fail/tree_borrows/error-range.stderr
+++ b/src/tools/miri/tests/fail/tree_borrows/error-range.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: read access through <TAG> at ALLOC[0x5] is forbidden
   --> tests/fail/tree_borrows/error-range.rs:LL:CC
    |
 LL |         rmut[5] += 1;
-   |         ^^^^^^^^^^^^ read access through <TAG> at ALLOC[0x5] is forbidden
+   |         ^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> has state Disabled which forbids this child read access
diff --git a/src/tools/miri/tests/fail/tree_borrows/fnentry_invalidation.stderr b/src/tools/miri/tests/fail/tree_borrows/fnentry_invalidation.stderr
index 6b8e8fc1147..ed345aae38f 100644
--- a/src/tools/miri/tests/fail/tree_borrows/fnentry_invalidation.stderr
+++ b/src/tools/miri/tests/fail/tree_borrows/fnentry_invalidation.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: write access through <TAG> at ALLOC[0x0] is forbidden
   --> tests/fail/tree_borrows/fnentry_invalidation.rs:LL:CC
    |
 LL |         *z = 2;
-   |         ^^^^^^ write access through <TAG> at ALLOC[0x0] is forbidden
+   |         ^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> has state Frozen which forbids this child write access
diff --git a/src/tools/miri/tests/fail/tree_borrows/outside-range.stderr b/src/tools/miri/tests/fail/tree_borrows/outside-range.stderr
index 39fb956f739..bbd33dc3560 100644
--- a/src/tools/miri/tests/fail/tree_borrows/outside-range.stderr
+++ b/src/tools/miri/tests/fail/tree_borrows/outside-range.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: write access through <TAG> at ALLOC[0x3] is forbidden
   --> tests/fail/tree_borrows/outside-range.rs:LL:CC
    |
 LL |     *y.add(3) = 42;
-   |     ^^^^^^^^^^^^^^ write access through <TAG> at ALLOC[0x3] is forbidden
+   |     ^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> is foreign to the protected tag <TAG> (i.e., it is not a child)
diff --git a/src/tools/miri/tests/fail/tree_borrows/parent_read_freezes_raw_mut.stderr b/src/tools/miri/tests/fail/tree_borrows/parent_read_freezes_raw_mut.stderr
index 15f257c3d95..a4119bc0178 100644
--- a/src/tools/miri/tests/fail/tree_borrows/parent_read_freezes_raw_mut.stderr
+++ b/src/tools/miri/tests/fail/tree_borrows/parent_read_freezes_raw_mut.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: write access through <TAG> at ALLOC[0x0] is forbidden
   --> tests/fail/tree_borrows/parent_read_freezes_raw_mut.rs:LL:CC
    |
 LL |         *ptr = 0;
-   |         ^^^^^^^^ write access through <TAG> at ALLOC[0x0] is forbidden
+   |         ^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> has state Frozen which forbids this child write access
diff --git a/src/tools/miri/tests/fail/tree_borrows/pass_invalid_mut.stderr b/src/tools/miri/tests/fail/tree_borrows/pass_invalid_mut.stderr
index f6da0b8ec52..de01a9f0e80 100644
--- a/src/tools/miri/tests/fail/tree_borrows/pass_invalid_mut.stderr
+++ b/src/tools/miri/tests/fail/tree_borrows/pass_invalid_mut.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: write access through <TAG> at ALLOC[0x0] is forbidden
   --> tests/fail/tree_borrows/pass_invalid_mut.rs:LL:CC
    |
 LL |     *nope = 31;
-   |     ^^^^^^^^^^ write access through <TAG> at ALLOC[0x0] is forbidden
+   |     ^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> is a child of the conflicting tag <TAG>
diff --git a/src/tools/miri/tests/fail/tree_borrows/protector-write-lazy.stderr b/src/tools/miri/tests/fail/tree_borrows/protector-write-lazy.stderr
index bb07776da61..af226b9e3be 100644
--- a/src/tools/miri/tests/fail/tree_borrows/protector-write-lazy.stderr
+++ b/src/tools/miri/tests/fail/tree_borrows/protector-write-lazy.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: reborrow through <TAG> at ALLOC[0x0] is forbidden
   --> tests/fail/tree_borrows/protector-write-lazy.rs:LL:CC
    |
 LL |     unsafe { println!("Value of funky: {}", *funky_ptr_lazy_on_fst_elem) }
-   |                                             ^^^^^^^^^^^^^^^^^^^^^^^^^^^ reborrow through <TAG> at ALLOC[0x0] is forbidden
+   |                                             ^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> has state Disabled which forbids this reborrow (acting as a child read access)
diff --git a/src/tools/miri/tests/fail/tree_borrows/repeated_foreign_read_lazy_conflicted.stderr b/src/tools/miri/tests/fail/tree_borrows/repeated_foreign_read_lazy_conflicted.stderr
index d81ecff6ccc..8421df5ab79 100644
--- a/src/tools/miri/tests/fail/tree_borrows/repeated_foreign_read_lazy_conflicted.stderr
+++ b/src/tools/miri/tests/fail/tree_borrows/repeated_foreign_read_lazy_conflicted.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: write access through <TAG> at ALLOC[0x0] is forbidden
   --> tests/fail/tree_borrows/repeated_foreign_read_lazy_conflicted.rs:LL:CC
    |
 LL |     *(x as *mut u8).byte_sub(1) = 42;
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ write access through <TAG> at ALLOC[0x0] is forbidden
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> has state Reserved (conflicted) which forbids this child write access
diff --git a/src/tools/miri/tests/fail/tree_borrows/reserved/cell-protected-write.stderr b/src/tools/miri/tests/fail/tree_borrows/reserved/cell-protected-write.stderr
index 10414df6a6a..00d5c3e6b67 100644
--- a/src/tools/miri/tests/fail/tree_borrows/reserved/cell-protected-write.stderr
+++ b/src/tools/miri/tests/fail/tree_borrows/reserved/cell-protected-write.stderr
@@ -12,7 +12,7 @@ error: Undefined Behavior: write access through <TAG> (y, callee:y, caller:y) at
   --> tests/fail/tree_borrows/reserved/cell-protected-write.rs:LL:CC
    |
 LL |             *y = 1;
-   |             ^^^^^^ write access through <TAG> (y, callee:y, caller:y) at ALLOC[0x0] is forbidden
+   |             ^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> (y, callee:y, caller:y) is foreign to the protected tag <TAG> (callee:x) (i.e., it is not a child)
diff --git a/src/tools/miri/tests/fail/tree_borrows/reserved/int-protected-write.stderr b/src/tools/miri/tests/fail/tree_borrows/reserved/int-protected-write.stderr
index a9683c9e614..c003938db33 100644
--- a/src/tools/miri/tests/fail/tree_borrows/reserved/int-protected-write.stderr
+++ b/src/tools/miri/tests/fail/tree_borrows/reserved/int-protected-write.stderr
@@ -12,7 +12,7 @@ error: Undefined Behavior: write access through <TAG> (y, callee:y, caller:y) at
   --> tests/fail/tree_borrows/reserved/int-protected-write.rs:LL:CC
    |
 LL |             *y = 0;
-   |             ^^^^^^ write access through <TAG> (y, callee:y, caller:y) at ALLOC[0x0] is forbidden
+   |             ^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> (y, callee:y, caller:y) is foreign to the protected tag <TAG> (callee:x) (i.e., it is not a child)
diff --git a/src/tools/miri/tests/fail/tree_borrows/reservedim_spurious_write.with.stderr b/src/tools/miri/tests/fail/tree_borrows/reservedim_spurious_write.with.stderr
index 47341e027d7..a8db7070333 100644
--- a/src/tools/miri/tests/fail/tree_borrows/reservedim_spurious_write.with.stderr
+++ b/src/tools/miri/tests/fail/tree_borrows/reservedim_spurious_write.with.stderr
@@ -16,7 +16,7 @@ error: Undefined Behavior: write access through <TAG> at ALLOC[0x0] is forbidden
   --> tests/fail/tree_borrows/reservedim_spurious_write.rs:LL:CC
    |
 LL |         unsafe { *y = 13 }
-   |                  ^^^^^^^ write access through <TAG> at ALLOC[0x0] is forbidden
+   |                  ^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> has state Disabled which forbids this child write access
diff --git a/src/tools/miri/tests/fail/tree_borrows/reservedim_spurious_write.without.stderr b/src/tools/miri/tests/fail/tree_borrows/reservedim_spurious_write.without.stderr
index 504b8cc0ac7..5eeefd450c6 100644
--- a/src/tools/miri/tests/fail/tree_borrows/reservedim_spurious_write.without.stderr
+++ b/src/tools/miri/tests/fail/tree_borrows/reservedim_spurious_write.without.stderr
@@ -16,7 +16,7 @@ error: Undefined Behavior: write access through <TAG> at ALLOC[0x0] is forbidden
   --> tests/fail/tree_borrows/reservedim_spurious_write.rs:LL:CC
    |
 LL |         unsafe { *y = 13 }
-   |                  ^^^^^^^ write access through <TAG> at ALLOC[0x0] is forbidden
+   |                  ^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> has state Disabled which forbids this child write access
diff --git a/src/tools/miri/tests/fail/tree_borrows/return_invalid_mut.stderr b/src/tools/miri/tests/fail/tree_borrows/return_invalid_mut.stderr
index 81fa3262877..a0ebf0ecbd2 100644
--- a/src/tools/miri/tests/fail/tree_borrows/return_invalid_mut.stderr
+++ b/src/tools/miri/tests/fail/tree_borrows/return_invalid_mut.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: write access through <TAG> at ALLOC[0x4] is forbidden
   --> tests/fail/tree_borrows/return_invalid_mut.rs:LL:CC
    |
 LL |     *ret = 3;
-   |     ^^^^^^^^ write access through <TAG> at ALLOC[0x4] is forbidden
+   |     ^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> is a child of the conflicting tag <TAG>
diff --git a/src/tools/miri/tests/fail/tree_borrows/spurious_read.stderr b/src/tools/miri/tests/fail/tree_borrows/spurious_read.stderr
index bd26b4e36df..a3b0d5f13ad 100644
--- a/src/tools/miri/tests/fail/tree_borrows/spurious_read.stderr
+++ b/src/tools/miri/tests/fail/tree_borrows/spurious_read.stderr
@@ -15,7 +15,7 @@ error: Undefined Behavior: write access through <TAG> at ALLOC[0x0] is forbidden
   --> tests/fail/tree_borrows/spurious_read.rs:LL:CC
    |
 LL |                 *y = 2;
-   |                 ^^^^^^ write access through <TAG> at ALLOC[0x0] is forbidden
+   |                 ^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> has state Reserved (conflicted) which forbids this child write access
diff --git a/src/tools/miri/tests/fail/tree_borrows/strongly-protected.stderr b/src/tools/miri/tests/fail/tree_borrows/strongly-protected.stderr
index f6197a2acb3..56617f6d6a6 100644
--- a/src/tools/miri/tests/fail/tree_borrows/strongly-protected.stderr
+++ b/src/tools/miri/tests/fail/tree_borrows/strongly-protected.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: deallocation through <TAG> at ALLOC[0x0] is forbidden
   --> RUSTLIB/alloc/src/boxed.rs:LL:CC
    |
 LL |                 self.1.deallocate(From::from(ptr.cast()), layout);
-   |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ deallocation through <TAG> at ALLOC[0x0] is forbidden
+   |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the allocation of the accessed tag <TAG> also contains the strongly protected tag <TAG>
diff --git a/src/tools/miri/tests/fail/tree_borrows/subtree_traversal_skipping_diagnostics.stderr b/src/tools/miri/tests/fail/tree_borrows/subtree_traversal_skipping_diagnostics.stderr
index d3ad2a39f2d..8669a14ecc7 100644
--- a/src/tools/miri/tests/fail/tree_borrows/subtree_traversal_skipping_diagnostics.stderr
+++ b/src/tools/miri/tests/fail/tree_borrows/subtree_traversal_skipping_diagnostics.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: write access through <TAG> at ALLOC[0x0] is forbidden
   --> tests/fail/tree_borrows/subtree_traversal_skipping_diagnostics.rs:LL:CC
    |
 LL |     *m = 42;
-   |     ^^^^^^^ write access through <TAG> at ALLOC[0x0] is forbidden
+   |     ^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> is a child of the conflicting tag <TAG>
diff --git a/src/tools/miri/tests/fail/tree_borrows/write-during-2phase.stderr b/src/tools/miri/tests/fail/tree_borrows/write-during-2phase.stderr
index 21178dad050..693d1853550 100644
--- a/src/tools/miri/tests/fail/tree_borrows/write-during-2phase.stderr
+++ b/src/tools/miri/tests/fail/tree_borrows/write-during-2phase.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: reborrow through <TAG> at ALLOC[0x0] is forbidden
   --> tests/fail/tree_borrows/write-during-2phase.rs:LL:CC
    |
 LL |     fn add(&mut self, n: u64) -> u64 {
-   |            ^^^^^^^^^ reborrow through <TAG> at ALLOC[0x0] is forbidden
+   |            ^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: the accessed tag <TAG> has state Disabled which forbids this reborrow (acting as a child read access)
diff --git a/src/tools/miri/tests/fail/type-too-large.stderr b/src/tools/miri/tests/fail/type-too-large.stderr
index cd27b246389..8c05f3a7e0b 100644
--- a/src/tools/miri/tests/fail/type-too-large.stderr
+++ b/src/tools/miri/tests/fail/type-too-large.stderr
@@ -2,7 +2,7 @@ error: post-monomorphization error: values of the type `[u8; 2305843011361177600
   --> tests/fail/type-too-large.rs:LL:CC
    |
 LL |     _fat = [0; (1u64 << 61) as usize + (1u64 << 31) as usize];
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ values of the type `[u8; 2305843011361177600]` are too big for the target architecture
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ post-monomorphization error occurred here
    |
    = note: BACKTRACE:
    = note: inside `main` at tests/fail/type-too-large.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/unaligned_pointers/alignment.stderr b/src/tools/miri/tests/fail/unaligned_pointers/alignment.stderr
index 8bbb4dfdb60..bc344bbbf7e 100644
--- a/src/tools/miri/tests/fail/unaligned_pointers/alignment.stderr
+++ b/src/tools/miri/tests/fail/unaligned_pointers/alignment.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: accessing memory based on pointer with alignment ALIG
   --> tests/fail/unaligned_pointers/alignment.rs:LL:CC
    |
 LL |         *(x_ptr as *mut u32) = 42; *(x_ptr.add(1) as *mut u32) = 42;
-   | ^ accessing memory based on pointer with alignment ALIGN, but alignment ALIGN is required
+   | ^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/unaligned_pointers/atomic_unaligned.stderr b/src/tools/miri/tests/fail/unaligned_pointers/atomic_unaligned.stderr
index e0f9d011ce4..a76d2f04f3f 100644
--- a/src/tools/miri/tests/fail/unaligned_pointers/atomic_unaligned.stderr
+++ b/src/tools/miri/tests/fail/unaligned_pointers/atomic_unaligned.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: accessing memory with alignment ALIGN, but alignment
   --> tests/fail/unaligned_pointers/atomic_unaligned.rs:LL:CC
    |
 LL |         intrinsics::atomic_load::<_, { intrinsics::AtomicOrdering::SeqCst }>(zptr);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ accessing memory with alignment ALIGN, but alignment ALIGN is required
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this usually indicates that your program performed an invalid operation and caused Undefined Behavior
    = help: but due to `-Zmiri-symbolic-alignment-check`, alignment errors can also be false positives
diff --git a/src/tools/miri/tests/fail/unaligned_pointers/drop_in_place.stderr b/src/tools/miri/tests/fail/unaligned_pointers/drop_in_place.stderr
index 75efa5ff806..72aeb0fdf8e 100644
--- a/src/tools/miri/tests/fail/unaligned_pointers/drop_in_place.stderr
+++ b/src/tools/miri/tests/fail/unaligned_pointers/drop_in_place.stderr
@@ -1,8 +1,8 @@
 error: Undefined Behavior: constructing invalid value: encountered an unaligned reference (required ALIGN byte alignment but found ALIGN)
   --> RUSTLIB/core/src/ptr/mod.rs:LL:CC
    |
-LL | pub unsafe fn drop_in_place<T: ?Sized>(to_drop: *mut T) {
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ constructing invalid value: encountered an unaligned reference (required ALIGN byte alignment but found ALIGN)
+LL | pub unsafe fn drop_in_place<T: PointeeSized>(to_drop: *mut T) {
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/unaligned_pointers/dyn_alignment.stderr b/src/tools/miri/tests/fail/unaligned_pointers/dyn_alignment.stderr
index 72cded1c079..ddd4641f7ef 100644
--- a/src/tools/miri/tests/fail/unaligned_pointers/dyn_alignment.stderr
+++ b/src/tools/miri/tests/fail/unaligned_pointers/dyn_alignment.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value: encountered an unaligned
   --> tests/fail/unaligned_pointers/dyn_alignment.rs:LL:CC
    |
 LL |         let _ptr = &*ptr;
-   |                    ^^^^^ constructing invalid value: encountered an unaligned reference (required ALIGN byte alignment but found ALIGN)
+   |                    ^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/unaligned_pointers/field_requires_parent_struct_alignment.stderr b/src/tools/miri/tests/fail/unaligned_pointers/field_requires_parent_struct_alignment.stderr
index 04ecf618fc0..d2a5f83a43d 100644
--- a/src/tools/miri/tests/fail/unaligned_pointers/field_requires_parent_struct_alignment.stderr
+++ b/src/tools/miri/tests/fail/unaligned_pointers/field_requires_parent_struct_alignment.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: accessing memory based on pointer with alignment ALIG
   --> tests/fail/unaligned_pointers/field_requires_parent_struct_alignment.rs:LL:CC
    |
 LL |     unsafe { (*x).x }
-   |              ^^^^^^ accessing memory based on pointer with alignment ALIGN, but alignment ALIGN is required
+   |              ^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/unaligned_pointers/field_requires_parent_struct_alignment2.stderr b/src/tools/miri/tests/fail/unaligned_pointers/field_requires_parent_struct_alignment2.stderr
index da5a34a8dc6..39540fc8320 100644
--- a/src/tools/miri/tests/fail/unaligned_pointers/field_requires_parent_struct_alignment2.stderr
+++ b/src/tools/miri/tests/fail/unaligned_pointers/field_requires_parent_struct_alignment2.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: accessing memory based on pointer with alignment ALIG
   --> tests/fail/unaligned_pointers/field_requires_parent_struct_alignment2.rs:LL:CC
    |
 LL |     unsafe { (*x).packed.x }
-   |              ^^^^^^^^^^^^^ accessing memory based on pointer with alignment ALIGN, but alignment ALIGN is required
+   |              ^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/unaligned_pointers/intptrcast_alignment_check.stderr b/src/tools/miri/tests/fail/unaligned_pointers/intptrcast_alignment_check.stderr
index e0e866b25c8..15fc1a768f9 100644
--- a/src/tools/miri/tests/fail/unaligned_pointers/intptrcast_alignment_check.stderr
+++ b/src/tools/miri/tests/fail/unaligned_pointers/intptrcast_alignment_check.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: accessing memory based on pointer with alignment ALIG
   --> tests/fail/unaligned_pointers/intptrcast_alignment_check.rs:LL:CC
    |
 LL |     unsafe { *u16_ptr = 2 };
-   |              ^^^^^^^^^^^^ accessing memory based on pointer with alignment ALIGN, but alignment ALIGN is required
+   |              ^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this usually indicates that your program performed an invalid operation and caused Undefined Behavior
    = help: but due to `-Zmiri-symbolic-alignment-check`, alignment errors can also be false positives
diff --git a/src/tools/miri/tests/fail/unaligned_pointers/promise_alignment.call_unaligned_ptr.stderr b/src/tools/miri/tests/fail/unaligned_pointers/promise_alignment.call_unaligned_ptr.stderr
index 91df7cf47a7..8d31f110ef4 100644
--- a/src/tools/miri/tests/fail/unaligned_pointers/promise_alignment.call_unaligned_ptr.stderr
+++ b/src/tools/miri/tests/fail/unaligned_pointers/promise_alignment.call_unaligned_ptr.stderr
@@ -2,7 +2,7 @@ error: unsupported operation: `miri_promise_symbolic_alignment`: pointer is not
   --> tests/fail/unaligned_pointers/promise_alignment.rs:LL:CC
    |
 LL |         unsafe { utils::miri_promise_symbolic_alignment(align8.add(1).cast(), 8) };
-   |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `miri_promise_symbolic_alignment`: pointer is not actually aligned
+   |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ unsupported operation occurred here
    |
    = help: this is likely not a bug in the program; it indicates that the program performed an operation that Miri does not support
    = note: BACKTRACE:
diff --git a/src/tools/miri/tests/fail/unaligned_pointers/promise_alignment.read_unaligned_ptr.stderr b/src/tools/miri/tests/fail/unaligned_pointers/promise_alignment.read_unaligned_ptr.stderr
index 1e984aa3efd..85eec253a77 100644
--- a/src/tools/miri/tests/fail/unaligned_pointers/promise_alignment.read_unaligned_ptr.stderr
+++ b/src/tools/miri/tests/fail/unaligned_pointers/promise_alignment.read_unaligned_ptr.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: accessing memory based on pointer with alignment ALIG
   --> tests/fail/unaligned_pointers/promise_alignment.rs:LL:CC
    |
 LL |         let _val = unsafe { align8.cast::<Align16>().read() };
-   |                             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ accessing memory based on pointer with alignment ALIGN, but alignment ALIGN is required
+   |                             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this usually indicates that your program performed an invalid operation and caused Undefined Behavior
    = help: but due to `-Zmiri-symbolic-alignment-check`, alignment errors can also be false positives
diff --git a/src/tools/miri/tests/fail/unaligned_pointers/promise_alignment_zero.stderr b/src/tools/miri/tests/fail/unaligned_pointers/promise_alignment_zero.stderr
index c687d998613..600e39907a2 100644
--- a/src/tools/miri/tests/fail/unaligned_pointers/promise_alignment_zero.stderr
+++ b/src/tools/miri/tests/fail/unaligned_pointers/promise_alignment_zero.stderr
@@ -2,7 +2,7 @@ error: unsupported operation: `miri_promise_symbolic_alignment`: alignment must
   --> tests/fail/unaligned_pointers/promise_alignment_zero.rs:LL:CC
    |
 LL |     unsafe { utils::miri_promise_symbolic_alignment(buffer.as_ptr().cast(), 0) };
-   |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `miri_promise_symbolic_alignment`: alignment must be a power of 2, got 0
+   |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ unsupported operation occurred here
    |
    = help: this is likely not a bug in the program; it indicates that the program performed an operation that Miri does not support
    = note: BACKTRACE:
diff --git a/src/tools/miri/tests/fail/unaligned_pointers/reference_to_packed.stderr b/src/tools/miri/tests/fail/unaligned_pointers/reference_to_packed.stderr
index 9adbd7f8153..a91be376bd1 100644
--- a/src/tools/miri/tests/fail/unaligned_pointers/reference_to_packed.stderr
+++ b/src/tools/miri/tests/fail/unaligned_pointers/reference_to_packed.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value: encountered an unaligned
   --> tests/fail/unaligned_pointers/reference_to_packed.rs:LL:CC
    |
 LL |     mem::transmute(x)
-   |     ^^^^^^^^^^^^^^^^^ constructing invalid value: encountered an unaligned reference (required ALIGN byte alignment but found ALIGN)
+   |     ^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr1.stderr b/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr1.stderr
index 90cfb4245c8..ccf7f833a6b 100644
--- a/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr1.stderr
+++ b/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr1.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: accessing memory based on pointer with alignment ALIG
   --> tests/fail/unaligned_pointers/unaligned_ptr1.rs:LL:CC
    |
 LL |         let _x = unsafe { *x };
-   |                           ^^ accessing memory based on pointer with alignment ALIGN, but alignment ALIGN is required
+   |                           ^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr2.stderr b/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr2.stderr
index 57ac8553930..99d26a78bf0 100644
--- a/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr2.stderr
+++ b/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr2.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: accessing memory based on pointer with alignment ALIG
   --> tests/fail/unaligned_pointers/unaligned_ptr2.rs:LL:CC
    |
 LL |     let _x = unsafe { *x };
-   |                       ^^ accessing memory based on pointer with alignment ALIGN, but alignment ALIGN is required
+   |                       ^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr3.stderr b/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr3.stderr
index d8ab546af6a..7cdcc47455e 100644
--- a/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr3.stderr
+++ b/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr3.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: accessing memory based on pointer with alignment ALIG
   --> tests/fail/unaligned_pointers/unaligned_ptr3.rs:LL:CC
    |
 LL |         let _x = unsafe { *x };
-   |                           ^^ accessing memory based on pointer with alignment ALIGN, but alignment ALIGN is required
+   |                           ^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr4.stderr b/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr4.stderr
index 5fe342c9b31..0d511c532f3 100644
--- a/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr4.stderr
+++ b/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr4.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: accessing memory based on pointer with alignment ALIG
   --> tests/fail/unaligned_pointers/unaligned_ptr4.rs:LL:CC
    |
 LL |         let _val = unsafe { *ptr };
-   |                             ^^^^ accessing memory based on pointer with alignment ALIGN, but alignment ALIGN is required
+   |                             ^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr_zst.stderr b/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr_zst.stderr
index 1ae8d954882..ebcaa460462 100644
--- a/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr_zst.stderr
+++ b/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr_zst.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: accessing memory based on pointer with alignment ALIG
   --> tests/fail/unaligned_pointers/unaligned_ptr_zst.rs:LL:CC
    |
 LL |         let _x = unsafe { *x };
-   |                           ^^ accessing memory based on pointer with alignment ALIGN, but alignment ALIGN is required
+   |                           ^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ref_addr_of.stderr b/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ref_addr_of.stderr
index d7561c57a8c..86e7e73417a 100644
--- a/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ref_addr_of.stderr
+++ b/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ref_addr_of.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value: encountered an unaligned
   --> tests/fail/unaligned_pointers/unaligned_ref_addr_of.rs:LL:CC
    |
 LL |         let _x = unsafe { &*x };
-   |                           ^^^ constructing invalid value: encountered an unaligned reference (required ALIGN byte alignment but found ALIGN)
+   |                           ^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/uninit/padding-enum.stderr b/src/tools/miri/tests/fail/uninit/padding-enum.stderr
index 765e7cc4e63..a9a5568f4e8 100644
--- a/src/tools/miri/tests/fail/uninit/padding-enum.stderr
+++ b/src/tools/miri/tests/fail/uninit/padding-enum.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: using uninitialized data, but this operation requires
   --> tests/fail/uninit/padding-enum.rs:LL:CC
    |
 LL |         let _val = *c.add(padding_offset);
-   |                    ^^^^^^^^^^^^^^^^^^^^^^ using uninitialized data, but this operation requires initialized memory
+   |                    ^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/uninit/padding-pair.stderr b/src/tools/miri/tests/fail/uninit/padding-pair.stderr
index f4ce802b157..d281a351d41 100644
--- a/src/tools/miri/tests/fail/uninit/padding-pair.stderr
+++ b/src/tools/miri/tests/fail/uninit/padding-pair.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: using uninitialized data, but this operation requires
   --> tests/fail/uninit/padding-pair.rs:LL:CC
    |
 LL |     let v = unsafe { *z.offset(first_undef) };
-   |                      ^^^^^^^^^^^^^^^^^^^^^^ using uninitialized data, but this operation requires initialized memory
+   |                      ^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/uninit/padding-struct-in-union.stderr b/src/tools/miri/tests/fail/uninit/padding-struct-in-union.stderr
index 5e9dabd5644..87a423e4665 100644
--- a/src/tools/miri/tests/fail/uninit/padding-struct-in-union.stderr
+++ b/src/tools/miri/tests/fail/uninit/padding-struct-in-union.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value at .bytes[2]: encountered
   --> tests/fail/uninit/padding-struct-in-union.rs:LL:CC
    |
 LL |     let _val = unsafe { (foobar.foo, foobar.bar) };
-   |                                      ^^^^^^^^^^ constructing invalid value at .bytes[2]: encountered uninitialized memory, but expected an integer
+   |                                      ^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/uninit/padding-struct.stderr b/src/tools/miri/tests/fail/uninit/padding-struct.stderr
index f27783c17e9..3298f6a4510 100644
--- a/src/tools/miri/tests/fail/uninit/padding-struct.stderr
+++ b/src/tools/miri/tests/fail/uninit/padding-struct.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: using uninitialized data, but this operation requires
   --> tests/fail/uninit/padding-struct.rs:LL:CC
    |
 LL |         let _val = *c.add(1);
-   |                    ^^^^^^^^^ using uninitialized data, but this operation requires initialized memory
+   |                    ^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/uninit/padding-union.stderr b/src/tools/miri/tests/fail/uninit/padding-union.stderr
index 248b06a14fe..fa07eedd891 100644
--- a/src/tools/miri/tests/fail/uninit/padding-union.stderr
+++ b/src/tools/miri/tests/fail/uninit/padding-union.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value at [1]: encountered uninit
   --> tests/fail/uninit/padding-union.rs:LL:CC
    |
 LL |         let _val = *c;
-   |                    ^^ constructing invalid value at [1]: encountered uninitialized memory, but expected an integer
+   |                    ^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/uninit/padding-wide-ptr.stderr b/src/tools/miri/tests/fail/uninit/padding-wide-ptr.stderr
index 219bee45fe8..d92d05ae631 100644
--- a/src/tools/miri/tests/fail/uninit/padding-wide-ptr.stderr
+++ b/src/tools/miri/tests/fail/uninit/padding-wide-ptr.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: using uninitialized data, but this operation requires
   --> tests/fail/uninit/padding-wide-ptr.rs:LL:CC
    |
 LL |         let _val = *c.add(mem::size_of::<*const u8>());
-   |                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ using uninitialized data, but this operation requires initialized memory
+   |                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/uninit/transmute-pair-uninit.stderr b/src/tools/miri/tests/fail/uninit/transmute-pair-uninit.stderr
index 7fe88df560c..0ae0ce5de9c 100644
--- a/src/tools/miri/tests/fail/uninit/transmute-pair-uninit.stderr
+++ b/src/tools/miri/tests/fail/uninit/transmute-pair-uninit.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: using uninitialized data, but this operation requires
   --> tests/fail/uninit/transmute-pair-uninit.rs:LL:CC
    |
 LL |     let v = unsafe { *z.offset(first_undef) };
-   |                      ^^^^^^^^^^^^^^^^^^^^^^ using uninitialized data, but this operation requires initialized memory
+   |                      ^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/uninit/uninit-after-aggregate-assign.stderr b/src/tools/miri/tests/fail/uninit/uninit-after-aggregate-assign.stderr
index ec6ba3fea7d..8086d375855 100644
--- a/src/tools/miri/tests/fail/uninit/uninit-after-aggregate-assign.stderr
+++ b/src/tools/miri/tests/fail/uninit/uninit-after-aggregate-assign.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value at [1]: encountered uninit
   --> tests/fail/uninit/uninit-after-aggregate-assign.rs:LL:CC
    |
 LL |             _val = *sptr2; // should hence be UB
-   |             ^^^^^^^^^^^^^ constructing invalid value at [1]: encountered uninitialized memory, but expected an integer
+   |             ^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/uninit/uninit_alloc_diagnostic.stderr b/src/tools/miri/tests/fail/uninit/uninit_alloc_diagnostic.stderr
index 0996e5d11ef..25a9bddb42c 100644
--- a/src/tools/miri/tests/fail/uninit/uninit_alloc_diagnostic.stderr
+++ b/src/tools/miri/tests/fail/uninit/uninit_alloc_diagnostic.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: reading memory at ALLOC[0x0..0x10], but memory is uni
   --> RUSTLIB/core/src/slice/cmp.rs:LL:CC
    |
 LL |         let mut order = unsafe { compare_bytes(left, right, len) as isize };
-   |                                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ reading memory at ALLOC[0x0..0x10], but memory is uninitialized at [0x4..0x10], and this operation requires initialized memory
+   |                                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/uninit/uninit_alloc_diagnostic_with_provenance.stderr b/src/tools/miri/tests/fail/uninit/uninit_alloc_diagnostic_with_provenance.stderr
index bcde9377c54..d3253317fae 100644
--- a/src/tools/miri/tests/fail/uninit/uninit_alloc_diagnostic_with_provenance.stderr
+++ b/src/tools/miri/tests/fail/uninit/uninit_alloc_diagnostic_with_provenance.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: reading memory at ALLOC[0x0..0x8], but memory is unin
   --> RUSTLIB/core/src/slice/cmp.rs:LL:CC
    |
 LL |         let mut order = unsafe { compare_bytes(left, right, len) as isize };
-   |                                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ reading memory at ALLOC[0x0..0x8], but memory is uninitialized at [0x4..0x8], and this operation requires initialized memory
+   |                                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/uninit/uninit_byte_read.stderr b/src/tools/miri/tests/fail/uninit/uninit_byte_read.stderr
index 5da89976b03..d2a5a2d3831 100644
--- a/src/tools/miri/tests/fail/uninit/uninit_byte_read.stderr
+++ b/src/tools/miri/tests/fail/uninit/uninit_byte_read.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: using uninitialized data, but this operation requires
   --> tests/fail/uninit/uninit_byte_read.rs:LL:CC
    |
 LL |     let undef = unsafe { *v.as_ptr().add(5) };
-   |                          ^^^^^^^^^^^^^^^^^^ using uninitialized data, but this operation requires initialized memory
+   |                          ^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/unreachable.stderr b/src/tools/miri/tests/fail/unreachable.stderr
index 46c956ff77e..4b1820c9cef 100644
--- a/src/tools/miri/tests/fail/unreachable.stderr
+++ b/src/tools/miri/tests/fail/unreachable.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: entering unreachable code
   --> tests/fail/unreachable.rs:LL:CC
    |
 LL |     unsafe { std::hint::unreachable_unchecked() }
-   |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ entering unreachable code
+   |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/unsized-local.rs b/src/tools/miri/tests/fail/unsized-local.rs
deleted file mode 100644
index ceccae4e3e7..00000000000
--- a/src/tools/miri/tests/fail/unsized-local.rs
+++ /dev/null
@@ -1,23 +0,0 @@
-#![feature(unsized_locals)]
-#![allow(incomplete_features)]
-
-fn main() {
-    pub trait Foo {
-        fn foo(self) -> String;
-    }
-
-    struct A;
-
-    impl Foo for A {
-        fn foo(self) -> String {
-            format!("hello")
-        }
-    }
-
-    let x = *(Box::new(A) as Box<dyn Foo>); //~ERROR: unsized locals are not supported
-    assert_eq!(x.foo(), format!("hello"));
-
-    // I'm not sure whether we want this to work
-    let x = Box::new(A) as Box<dyn Foo>;
-    assert_eq!(x.foo(), format!("hello"));
-}
diff --git a/src/tools/miri/tests/fail/unsized-local.stderr b/src/tools/miri/tests/fail/unsized-local.stderr
deleted file mode 100644
index 548f3d66c73..00000000000
--- a/src/tools/miri/tests/fail/unsized-local.stderr
+++ /dev/null
@@ -1,14 +0,0 @@
-error: unsupported operation: unsized locals are not supported
-  --> tests/fail/unsized-local.rs:LL:CC
-   |
-LL |     let x = *(Box::new(A) as Box<dyn Foo>);
-   |         ^ unsized locals are not supported
-   |
-   = help: this is likely not a bug in the program; it indicates that the program performed an operation that Miri does not support
-   = note: BACKTRACE:
-   = note: inside `main` at tests/fail/unsized-local.rs:LL:CC
-
-note: some details are omitted, run with `MIRIFLAGS=-Zmiri-backtrace=full` for a verbose backtrace
-
-error: aborting due to 1 previous error
-
diff --git a/src/tools/miri/tests/fail/unsupported_foreign_function.stderr b/src/tools/miri/tests/fail/unsupported_foreign_function.stderr
index bbfc5c31256..63467859ed2 100644
--- a/src/tools/miri/tests/fail/unsupported_foreign_function.stderr
+++ b/src/tools/miri/tests/fail/unsupported_foreign_function.stderr
@@ -2,7 +2,7 @@ error: unsupported operation: can't call foreign function `foo` on $OS
   --> tests/fail/unsupported_foreign_function.rs:LL:CC
    |
 LL |         foo();
-   |         ^^^^^ can't call foreign function `foo` on $OS
+   |         ^^^^^ unsupported operation occurred here
    |
    = help: this means the program tried to do something Miri does not support; it does not indicate a bug in the program
    = note: BACKTRACE:
diff --git a/src/tools/miri/tests/fail/unwind-action-terminate.stderr b/src/tools/miri/tests/fail/unwind-action-terminate.stderr
index 222d4fb2866..5fa485752a4 100644
--- a/src/tools/miri/tests/fail/unwind-action-terminate.stderr
+++ b/src/tools/miri/tests/fail/unwind-action-terminate.stderr
@@ -12,7 +12,7 @@ error: abnormal termination: the program aborted execution
   --> RUSTLIB/std/src/sys/pal/PLATFORM/mod.rs:LL:CC
    |
 LL | ABORT()
-   | ^ the program aborted execution
+   | ^ abnormal termination occurred here
    |
    = note: BACKTRACE:
    = note: inside `std::sys::pal::PLATFORM::abort_internal` at RUSTLIB/std/src/sys/pal/PLATFORM/mod.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/validity/box-custom-alloc-dangling-ptr.stderr b/src/tools/miri/tests/fail/validity/box-custom-alloc-dangling-ptr.stderr
index 76d7e66cfc5..36a31879041 100644
--- a/src/tools/miri/tests/fail/validity/box-custom-alloc-dangling-ptr.stderr
+++ b/src/tools/miri/tests/fail/validity/box-custom-alloc-dangling-ptr.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value: encountered a dangling bo
   --> tests/fail/validity/box-custom-alloc-dangling-ptr.rs:LL:CC
    |
 LL |         std::mem::transmute(b)
-   |         ^^^^^^^^^^^^^^^^^^^^^^ constructing invalid value: encountered a dangling box (0x4[noalloc] has no provenance)
+   |         ^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/validity/box-custom-alloc-invalid-alloc.stderr b/src/tools/miri/tests/fail/validity/box-custom-alloc-invalid-alloc.stderr
index e151f80dde3..42c4a6e851b 100644
--- a/src/tools/miri/tests/fail/validity/box-custom-alloc-invalid-alloc.stderr
+++ b/src/tools/miri/tests/fail/validity/box-custom-alloc-invalid-alloc.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value at .1.my_alloc_field1: enc
   --> tests/fail/validity/box-custom-alloc-invalid-alloc.rs:LL:CC
    |
 LL |         std::mem::transmute(b)
-   |         ^^^^^^^^^^^^^^^^^^^^^^ constructing invalid value at .1.my_alloc_field1: encountered uninitialized memory, but expected an integer
+   |         ^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/validity/cast_fn_ptr_invalid_callee_arg.stderr b/src/tools/miri/tests/fail/validity/cast_fn_ptr_invalid_callee_arg.stderr
index 9b6b7098e5c..d2f75da47f1 100644
--- a/src/tools/miri/tests/fail/validity/cast_fn_ptr_invalid_callee_arg.stderr
+++ b/src/tools/miri/tests/fail/validity/cast_fn_ptr_invalid_callee_arg.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value: encountered a null refere
   --> tests/fail/validity/cast_fn_ptr_invalid_callee_arg.rs:LL:CC
    |
 LL |     g(0usize as *const i32)
-   |     ^^^^^^^^^^^^^^^^^^^^^^^ constructing invalid value: encountered a null reference
+   |     ^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/validity/cast_fn_ptr_invalid_callee_ret.stderr b/src/tools/miri/tests/fail/validity/cast_fn_ptr_invalid_callee_ret.stderr
index a0b7cc7a521..efe89c0d220 100644
--- a/src/tools/miri/tests/fail/validity/cast_fn_ptr_invalid_callee_ret.stderr
+++ b/src/tools/miri/tests/fail/validity/cast_fn_ptr_invalid_callee_ret.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value at .0: encountered 0, but
   --> tests/fail/validity/cast_fn_ptr_invalid_callee_ret.rs:LL:CC
    |
 LL |     f();
-   |     ^^^ constructing invalid value at .0: encountered 0, but expected something greater or equal to 1
+   |     ^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/validity/cast_fn_ptr_invalid_caller_arg.stderr b/src/tools/miri/tests/fail/validity/cast_fn_ptr_invalid_caller_arg.stderr
index 6af0e72b9c4..c370e19ef31 100644
--- a/src/tools/miri/tests/fail/validity/cast_fn_ptr_invalid_caller_arg.stderr
+++ b/src/tools/miri/tests/fail/validity/cast_fn_ptr_invalid_caller_arg.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value at .0: encountered 0, but
   --> tests/fail/validity/cast_fn_ptr_invalid_caller_arg.rs:LL:CC
    |
 LL |             Call(_res = f(*ptr), ReturnTo(retblock), UnwindContinue())
-   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ constructing invalid value at .0: encountered 0, but expected something greater or equal to 1
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/validity/cast_fn_ptr_invalid_caller_ret.stderr b/src/tools/miri/tests/fail/validity/cast_fn_ptr_invalid_caller_ret.stderr
index c02651c7cc9..e54d7105f17 100644
--- a/src/tools/miri/tests/fail/validity/cast_fn_ptr_invalid_caller_ret.stderr
+++ b/src/tools/miri/tests/fail/validity/cast_fn_ptr_invalid_caller_ret.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value: encountered a null refere
   --> tests/fail/validity/cast_fn_ptr_invalid_caller_ret.rs:LL:CC
    |
 LL |     let _x = g();
-   |              ^^^ constructing invalid value: encountered a null reference
+   |              ^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/validity/dangling_ref1.stderr b/src/tools/miri/tests/fail/validity/dangling_ref1.stderr
index 09634e5ae7b..b29826a9a3b 100644
--- a/src/tools/miri/tests/fail/validity/dangling_ref1.stderr
+++ b/src/tools/miri/tests/fail/validity/dangling_ref1.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value: encountered a dangling re
   --> tests/fail/validity/dangling_ref1.rs:LL:CC
    |
 LL |     let _x: &i32 = unsafe { mem::transmute(16usize) };
-   |                             ^^^^^^^^^^^^^^^^^^^^^^^ constructing invalid value: encountered a dangling reference (0x10[noalloc] has no provenance)
+   |                             ^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/validity/dangling_ref2.stderr b/src/tools/miri/tests/fail/validity/dangling_ref2.stderr
index fe7fe2795ef..b792fb5b944 100644
--- a/src/tools/miri/tests/fail/validity/dangling_ref2.stderr
+++ b/src/tools/miri/tests/fail/validity/dangling_ref2.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value: encountered a dangling re
   --> tests/fail/validity/dangling_ref2.rs:LL:CC
    |
 LL |     let _x: &i32 = unsafe { mem::transmute(ptr) };
-   |                             ^^^^^^^^^^^^^^^^^^^ constructing invalid value: encountered a dangling reference (going beyond the bounds of its allocation)
+   |                             ^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/validity/dangling_ref3.stderr b/src/tools/miri/tests/fail/validity/dangling_ref3.stderr
index fe40aaa122f..bcc4a796a87 100644
--- a/src/tools/miri/tests/fail/validity/dangling_ref3.stderr
+++ b/src/tools/miri/tests/fail/validity/dangling_ref3.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value: encountered a dangling re
   --> tests/fail/validity/dangling_ref3.rs:LL:CC
    |
 LL |     let _x: &i32 = unsafe { mem::transmute(dangling()) };
-   |                             ^^^^^^^^^^^^^^^^^^^^^^^^^^ constructing invalid value: encountered a dangling reference (use-after-free)
+   |                             ^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/validity/dyn-transmute-inner-binder.stderr b/src/tools/miri/tests/fail/validity/dyn-transmute-inner-binder.stderr
index cfdf279a605..8a43534bc2d 100644
--- a/src/tools/miri/tests/fail/validity/dyn-transmute-inner-binder.stderr
+++ b/src/tools/miri/tests/fail/validity/dyn-transmute-inner-binder.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value: wrong trait in wide point
   --> tests/fail/validity/dyn-transmute-inner-binder.rs:LL:CC
    |
 LL |     let y: &dyn Trait<for<'a> fn(&'a ())> = unsafe { std::mem::transmute(x) };
-   |                                                      ^^^^^^^^^^^^^^^^^^^^^^ constructing invalid value: wrong trait in wide pointer vtable: expected `Trait<for<'a> fn(&'a ())>`, but encountered `Trait<fn(&())>`
+   |                                                      ^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/validity/invalid_bool.stderr b/src/tools/miri/tests/fail/validity/invalid_bool.stderr
index 9bed0f716a0..7135f545c52 100644
--- a/src/tools/miri/tests/fail/validity/invalid_bool.stderr
+++ b/src/tools/miri/tests/fail/validity/invalid_bool.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value: encountered 0x02, but exp
   --> tests/fail/validity/invalid_bool.rs:LL:CC
    |
 LL |     let _b = unsafe { std::mem::transmute::<u8, bool>(2) };
-   |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ constructing invalid value: encountered 0x02, but expected a boolean
+   |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/validity/invalid_bool_op.stderr b/src/tools/miri/tests/fail/validity/invalid_bool_op.stderr
index ee84762fe40..faac61426bb 100644
--- a/src/tools/miri/tests/fail/validity/invalid_bool_op.stderr
+++ b/src/tools/miri/tests/fail/validity/invalid_bool_op.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: interpreting an invalid 8-bit value as a bool: 0x02
   --> tests/fail/validity/invalid_bool_op.rs:LL:CC
    |
 LL |     let _x = b == std::hint::black_box(true);
-   |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ interpreting an invalid 8-bit value as a bool: 0x02
+   |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/validity/invalid_bool_uninit.stderr b/src/tools/miri/tests/fail/validity/invalid_bool_uninit.stderr
index 487e3714b72..089fd2303e3 100644
--- a/src/tools/miri/tests/fail/validity/invalid_bool_uninit.stderr
+++ b/src/tools/miri/tests/fail/validity/invalid_bool_uninit.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value at [0]: encountered uninit
   --> tests/fail/validity/invalid_bool_uninit.rs:LL:CC
    |
 LL |     let _b = unsafe { MyUninit { init: () }.uninit };
-   |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ constructing invalid value at [0]: encountered uninitialized memory, but expected a boolean
+   |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/validity/invalid_char.stderr b/src/tools/miri/tests/fail/validity/invalid_char.stderr
index 5d258176cb6..720c09e692d 100644
--- a/src/tools/miri/tests/fail/validity/invalid_char.stderr
+++ b/src/tools/miri/tests/fail/validity/invalid_char.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value: encountered $HEX, but exp
   --> tests/fail/validity/invalid_char.rs:LL:CC
    |
 LL |     let _val = match unsafe { std::mem::transmute::<i32, char>(-1) } {
-   |                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ constructing invalid value: encountered $HEX, but expected a valid unicode scalar value (in `0..=$HEX` but not in `$HEX..=$HEX`)
+   |                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/validity/invalid_char_cast.stderr b/src/tools/miri/tests/fail/validity/invalid_char_cast.stderr
index b88f9f77208..c435e51d6be 100644
--- a/src/tools/miri/tests/fail/validity/invalid_char_cast.stderr
+++ b/src/tools/miri/tests/fail/validity/invalid_char_cast.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: interpreting an invalid 32-bit value as a char: $HEX
   --> tests/fail/validity/invalid_char_cast.rs:LL:CC
    |
 LL |             RET = *ptr as u32;
-   |             ^^^^^^^^^^^^^^^^^ interpreting an invalid 32-bit value as a char: $HEX
+   |             ^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/validity/invalid_char_match.stderr b/src/tools/miri/tests/fail/validity/invalid_char_match.stderr
index 9ce1631e67f..141305a0017 100644
--- a/src/tools/miri/tests/fail/validity/invalid_char_match.stderr
+++ b/src/tools/miri/tests/fail/validity/invalid_char_match.stderr
@@ -5,7 +5,7 @@ LL | /             match *ptr {
 LL | |                 '0' => ret,
 LL | |                 _ => ret,
 LL | |             }
-   | |_____________^ interpreting an invalid 32-bit value as a char: $HEX
+   | |_____________^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/validity/invalid_char_op.stderr b/src/tools/miri/tests/fail/validity/invalid_char_op.stderr
index 2d84ef3dda6..692d5764861 100644
--- a/src/tools/miri/tests/fail/validity/invalid_char_op.stderr
+++ b/src/tools/miri/tests/fail/validity/invalid_char_op.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: interpreting an invalid 32-bit value as a char: $HEX
   --> tests/fail/validity/invalid_char_op.rs:LL:CC
    |
 LL |     let _x = c == 'x';
-   |              ^^^^^^^^ interpreting an invalid 32-bit value as a char: $HEX
+   |              ^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/validity/invalid_char_uninit.stderr b/src/tools/miri/tests/fail/validity/invalid_char_uninit.stderr
index 6fd311df5ee..a4a61ed86a2 100644
--- a/src/tools/miri/tests/fail/validity/invalid_char_uninit.stderr
+++ b/src/tools/miri/tests/fail/validity/invalid_char_uninit.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value at [0]: encountered uninit
   --> tests/fail/validity/invalid_char_uninit.rs:LL:CC
    |
 LL |     let _b = unsafe { MyUninit { init: () }.uninit };
-   |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ constructing invalid value at [0]: encountered uninitialized memory, but expected a unicode scalar value
+   |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/validity/invalid_enum_cast.stderr b/src/tools/miri/tests/fail/validity/invalid_enum_cast.stderr
index 0736dfb2df1..b2d87641903 100644
--- a/src/tools/miri/tests/fail/validity/invalid_enum_cast.stderr
+++ b/src/tools/miri/tests/fail/validity/invalid_enum_cast.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: enum value has invalid tag: 0xff
   --> tests/fail/validity/invalid_enum_cast.rs:LL:CC
    |
 LL |         let _val = *ptr as u32;
-   |                    ^^^^^^^^^^^ enum value has invalid tag: 0xff
+   |                    ^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/validity/invalid_enum_op.stderr b/src/tools/miri/tests/fail/validity/invalid_enum_op.stderr
index d2cfa86de86..3dd8f650d2e 100644
--- a/src/tools/miri/tests/fail/validity/invalid_enum_op.stderr
+++ b/src/tools/miri/tests/fail/validity/invalid_enum_op.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: enum value has invalid tag: $HEX
   --> tests/fail/validity/invalid_enum_op.rs:LL:CC
    |
 LL |     let _val = mem::discriminant(&f);
-   |                ^^^^^^^^^^^^^^^^^^^^^ enum value has invalid tag: $HEX
+   |                ^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/validity/invalid_enum_tag.stderr b/src/tools/miri/tests/fail/validity/invalid_enum_tag.stderr
index 5721cfda932..3056643a191 100644
--- a/src/tools/miri/tests/fail/validity/invalid_enum_tag.stderr
+++ b/src/tools/miri/tests/fail/validity/invalid_enum_tag.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value at .<enum-tag>: encountere
   --> tests/fail/validity/invalid_enum_tag.rs:LL:CC
    |
 LL |     let _f = unsafe { std::mem::transmute::<i32, Foo>(42) };
-   |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ constructing invalid value at .<enum-tag>: encountered $HEX, but expected a valid enum tag
+   |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/validity/invalid_fnptr_null.stderr b/src/tools/miri/tests/fail/validity/invalid_fnptr_null.stderr
index a07b5babe1a..10cefa12865 100644
--- a/src/tools/miri/tests/fail/validity/invalid_fnptr_null.stderr
+++ b/src/tools/miri/tests/fail/validity/invalid_fnptr_null.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value: encountered a null functi
   --> tests/fail/validity/invalid_fnptr_null.rs:LL:CC
    |
 LL |     let _b: fn() = unsafe { std::mem::transmute(0usize) };
-   |                             ^^^^^^^^^^^^^^^^^^^^^^^^^^^ constructing invalid value: encountered a null function pointer
+   |                             ^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/validity/invalid_fnptr_uninit.stderr b/src/tools/miri/tests/fail/validity/invalid_fnptr_uninit.stderr
index 85fabc1836b..7e6fda25078 100644
--- a/src/tools/miri/tests/fail/validity/invalid_fnptr_uninit.stderr
+++ b/src/tools/miri/tests/fail/validity/invalid_fnptr_uninit.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value at [0]: encountered uninit
   --> tests/fail/validity/invalid_fnptr_uninit.rs:LL:CC
    |
 LL |     let _b = unsafe { MyUninit { init: () }.uninit };
-   |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ constructing invalid value at [0]: encountered uninitialized memory, but expected a function pointer
+   |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/validity/invalid_int_op.stderr b/src/tools/miri/tests/fail/validity/invalid_int_op.stderr
index c3f47df12f9..6e24cadfc20 100644
--- a/src/tools/miri/tests/fail/validity/invalid_int_op.stderr
+++ b/src/tools/miri/tests/fail/validity/invalid_int_op.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: using uninitialized data, but this operation requires
   --> tests/fail/validity/invalid_int_op.rs:LL:CC
    |
 LL |     let i = unsafe { std::mem::MaybeUninit::<i32>::uninit().assume_init() };
-   |                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ using uninitialized data, but this operation requires initialized memory
+   |                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/validity/invalid_wide_raw.stderr b/src/tools/miri/tests/fail/validity/invalid_wide_raw.stderr
index 5321dc0f4cf..c41766ae845 100644
--- a/src/tools/miri/tests/fail/validity/invalid_wide_raw.stderr
+++ b/src/tools/miri/tests/fail/validity/invalid_wide_raw.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value: encountered null pointer,
   --> tests/fail/validity/invalid_wide_raw.rs:LL:CC
    |
 LL |     dbg!(S { x: unsafe { std::mem::transmute((0usize, 0usize)) } });
-   |                          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ constructing invalid value: encountered null pointer, but expected a vtable pointer
+   |                          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/validity/match_binder_checks_validity1.stderr b/src/tools/miri/tests/fail/validity/match_binder_checks_validity1.stderr
index ec607512686..cde972ab6a2 100644
--- a/src/tools/miri/tests/fail/validity/match_binder_checks_validity1.stderr
+++ b/src/tools/miri/tests/fail/validity/match_binder_checks_validity1.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value: encountered a value of un
   --> tests/fail/validity/match_binder_checks_validity1.rs:LL:CC
    |
 LL |             _x => println!("hi from the void!"),
-   |             ^^ constructing invalid value: encountered a value of uninhabited type `main::Void`
+   |             ^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/validity/match_binder_checks_validity2.stderr b/src/tools/miri/tests/fail/validity/match_binder_checks_validity2.stderr
index 0375ead8f55..37625ace795 100644
--- a/src/tools/miri/tests/fail/validity/match_binder_checks_validity2.stderr
+++ b/src/tools/miri/tests/fail/validity/match_binder_checks_validity2.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value: encountered 0x03, but exp
   --> tests/fail/validity/match_binder_checks_validity2.rs:LL:CC
    |
 LL |             _x => println!("hi from the void!"),
-   |             ^^ constructing invalid value: encountered 0x03, but expected a boolean
+   |             ^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/validity/nonzero.stderr b/src/tools/miri/tests/fail/validity/nonzero.stderr
index bbf1f9a73ff..0c3a35d6b9f 100644
--- a/src/tools/miri/tests/fail/validity/nonzero.stderr
+++ b/src/tools/miri/tests/fail/validity/nonzero.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value: encountered 0, but expect
   --> tests/fail/validity/nonzero.rs:LL:CC
    |
 LL |     let _x = Some(unsafe { NonZero(0) });
-   |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^ constructing invalid value: encountered 0, but expected something greater or equal to 1
+   |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/validity/recursive-validity-ref-bool.stderr b/src/tools/miri/tests/fail/validity/recursive-validity-ref-bool.stderr
index 87ac8c17932..05203802d84 100644
--- a/src/tools/miri/tests/fail/validity/recursive-validity-ref-bool.stderr
+++ b/src/tools/miri/tests/fail/validity/recursive-validity-ref-bool.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value at .<deref>: encountered 0
   --> tests/fail/validity/recursive-validity-ref-bool.rs:LL:CC
    |
 LL |     let xref_wrong_type: &bool = unsafe { std::mem::transmute(xref) };
-   |                                           ^^^^^^^^^^^^^^^^^^^^^^^^^ constructing invalid value at .<deref>: encountered 0x03, but expected a boolean
+   |                                           ^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/validity/ref_to_uninhabited1.stderr b/src/tools/miri/tests/fail/validity/ref_to_uninhabited1.stderr
index 30acfef02ff..6a7cbda5ef8 100644
--- a/src/tools/miri/tests/fail/validity/ref_to_uninhabited1.stderr
+++ b/src/tools/miri/tests/fail/validity/ref_to_uninhabited1.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value: encountered a box pointin
   --> tests/fail/validity/ref_to_uninhabited1.rs:LL:CC
    |
 LL |         let x: Box<!> = transmute(&mut 42);
-   |                         ^^^^^^^^^^^^^^^^^^ constructing invalid value: encountered a box pointing to uninhabited type !
+   |                         ^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/validity/ref_to_uninhabited2.stderr b/src/tools/miri/tests/fail/validity/ref_to_uninhabited2.stderr
index 1015d1ec427..0cb126b2be3 100644
--- a/src/tools/miri/tests/fail/validity/ref_to_uninhabited2.stderr
+++ b/src/tools/miri/tests/fail/validity/ref_to_uninhabited2.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value: encountered a reference p
   --> tests/fail/validity/ref_to_uninhabited2.rs:LL:CC
    |
 LL |         let _x: &(i32, Void) = transmute(&42);
-   |                                ^^^^^^^^^^^^^^ constructing invalid value: encountered a reference pointing to uninhabited type (i32, Void)
+   |                                ^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/validity/too-big-slice.stderr b/src/tools/miri/tests/fail/validity/too-big-slice.stderr
index 2b0a8f03813..3405cafc645 100644
--- a/src/tools/miri/tests/fail/validity/too-big-slice.stderr
+++ b/src/tools/miri/tests/fail/validity/too-big-slice.stderr
@@ -1,8 +1,8 @@
 error: Undefined Behavior: constructing invalid value: encountered invalid reference metadata: slice is bigger than largest supported object
   --> tests/fail/validity/too-big-slice.rs:LL:CC
    |
-LL |         let _x: &[u8] = mem::transmute((ptr, usize::MAX));
-   |                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ constructing invalid value: encountered invalid reference metadata: slice is bigger than largest supported object
+LL | ...   let _x: &[u8] = mem::transmute((ptr, usize::MAX));
+   |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/validity/too-big-unsized.stderr b/src/tools/miri/tests/fail/validity/too-big-unsized.stderr
index 1e8b37979b0..f283ab96016 100644
--- a/src/tools/miri/tests/fail/validity/too-big-unsized.stderr
+++ b/src/tools/miri/tests/fail/validity/too-big-unsized.stderr
@@ -1,8 +1,8 @@
 error: Undefined Behavior: constructing invalid value: encountered invalid reference metadata: total size is bigger than largest supported object
   --> tests/fail/validity/too-big-unsized.rs:LL:CC
    |
-LL |         let _x: &MySlice = mem::transmute((ptr, isize::MAX as usize));
-   |                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ constructing invalid value: encountered invalid reference metadata: total size is bigger than largest supported object
+LL | ...   let _x: &MySlice = mem::transmute((ptr, isize::MAX as usize));
+   |                          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/validity/transmute_through_ptr.stderr b/src/tools/miri/tests/fail/validity/transmute_through_ptr.stderr
index bbb40d1f58f..c30c532496d 100644
--- a/src/tools/miri/tests/fail/validity/transmute_through_ptr.stderr
+++ b/src/tools/miri/tests/fail/validity/transmute_through_ptr.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value at .<enum-tag>: encountere
   --> tests/fail/validity/transmute_through_ptr.rs:LL:CC
    |
 LL |     let y = x; // reading this ought to be enough to trigger validation
-   |             ^ constructing invalid value at .<enum-tag>: encountered $HEX, but expected a valid enum tag
+   |             ^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/validity/uninit_float.stderr b/src/tools/miri/tests/fail/validity/uninit_float.stderr
index a6ca0f40f0d..1b948b062e1 100644
--- a/src/tools/miri/tests/fail/validity/uninit_float.stderr
+++ b/src/tools/miri/tests/fail/validity/uninit_float.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value at .value[0]: encountered
   --> tests/fail/validity/uninit_float.rs:LL:CC
    |
 LL |     let _val: [f32; 1] = unsafe { std::mem::uninitialized() };
-   |                                   ^^^^^^^^^^^^^^^^^^^^^^^^^ constructing invalid value at .value[0]: encountered uninitialized memory, but expected a floating point number
+   |                                   ^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/validity/uninit_integer.stderr b/src/tools/miri/tests/fail/validity/uninit_integer.stderr
index b983832799b..b17bdee65da 100644
--- a/src/tools/miri/tests/fail/validity/uninit_integer.stderr
+++ b/src/tools/miri/tests/fail/validity/uninit_integer.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value at .value[0]: encountered
   --> tests/fail/validity/uninit_integer.rs:LL:CC
    |
 LL |     let _val = unsafe { std::mem::MaybeUninit::<[usize; 1]>::uninit().assume_init() };
-   |                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ constructing invalid value at .value[0]: encountered uninitialized memory, but expected an integer
+   |                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/validity/uninit_raw_ptr.stderr b/src/tools/miri/tests/fail/validity/uninit_raw_ptr.stderr
index 83af585201a..269af6061c2 100644
--- a/src/tools/miri/tests/fail/validity/uninit_raw_ptr.stderr
+++ b/src/tools/miri/tests/fail/validity/uninit_raw_ptr.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value at .value[0]: encountered
   --> tests/fail/validity/uninit_raw_ptr.rs:LL:CC
    |
 LL |     let _val = unsafe { std::mem::MaybeUninit::<[*const u8; 1]>::uninit().assume_init() };
-   |                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ constructing invalid value at .value[0]: encountered uninitialized memory, but expected a raw pointer
+   |                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/validity/wrong-dyn-trait-assoc-type.stderr b/src/tools/miri/tests/fail/validity/wrong-dyn-trait-assoc-type.stderr
index 44939a5a838..23d43867920 100644
--- a/src/tools/miri/tests/fail/validity/wrong-dyn-trait-assoc-type.stderr
+++ b/src/tools/miri/tests/fail/validity/wrong-dyn-trait-assoc-type.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value: wrong trait in wide point
   --> tests/fail/validity/wrong-dyn-trait-assoc-type.rs:LL:CC
    |
 LL |     let v: Box<dyn Trait<Assoc = bool>> = unsafe { std::mem::transmute(v) };
-   |                                                    ^^^^^^^^^^^^^^^^^^^^^^ constructing invalid value: wrong trait in wide pointer vtable: expected `Trait<Assoc = bool>`, but encountered `Trait<Assoc = u8>`
+   |                                                    ^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/validity/wrong-dyn-trait-generic.stderr b/src/tools/miri/tests/fail/validity/wrong-dyn-trait-generic.stderr
index 0b5163f711e..c5df837a977 100644
--- a/src/tools/miri/tests/fail/validity/wrong-dyn-trait-generic.stderr
+++ b/src/tools/miri/tests/fail/validity/wrong-dyn-trait-generic.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value: wrong trait in wide point
   --> tests/fail/validity/wrong-dyn-trait-generic.rs:LL:CC
    |
 LL |     let _y: *const dyn Trait<u32> = unsafe { mem::transmute(x) };
-   |                                              ^^^^^^^^^^^^^^^^^ constructing invalid value: wrong trait in wide pointer vtable: expected `Trait<u32>`, but encountered `Trait<i32>`
+   |                                              ^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/validity/wrong-dyn-trait.stderr b/src/tools/miri/tests/fail/validity/wrong-dyn-trait.stderr
index 45c882bebdf..1dcbd9c774d 100644
--- a/src/tools/miri/tests/fail/validity/wrong-dyn-trait.stderr
+++ b/src/tools/miri/tests/fail/validity/wrong-dyn-trait.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: constructing invalid value: wrong trait in wide point
   --> tests/fail/validity/wrong-dyn-trait.rs:LL:CC
    |
 LL |     let _y: *const dyn fmt::Debug = unsafe { mem::transmute(x) };
-   |                                              ^^^^^^^^^^^^^^^^^ constructing invalid value: wrong trait in wide pointer vtable: expected `std::fmt::Debug`, but encountered `std::marker::Send`
+   |                                              ^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/weak_memory/weak_uninit.stderr b/src/tools/miri/tests/fail/weak_memory/weak_uninit.stderr
index 816bd323f4c..7adcb28e4bc 100644
--- a/src/tools/miri/tests/fail/weak_memory/weak_uninit.stderr
+++ b/src/tools/miri/tests/fail/weak_memory/weak_uninit.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: using uninitialized data, but this operation requires
   --> tests/fail/weak_memory/weak_uninit.rs:LL:CC
    |
 LL |     let j2 = spawn(move || x.load(Ordering::Relaxed));
-   |                            ^^^^^^^^^^^^^^^^^^^^^^^^^ using uninitialized data, but this operation requires initialized memory
+   |                            ^^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/fail/zst_local_oob.stderr b/src/tools/miri/tests/fail/zst_local_oob.stderr
index e9423096226..5bb29514d9a 100644
--- a/src/tools/miri/tests/fail/zst_local_oob.stderr
+++ b/src/tools/miri/tests/fail/zst_local_oob.stderr
@@ -2,7 +2,7 @@ error: Undefined Behavior: memory access failed: attempting to access 1 byte, bu
   --> tests/fail/zst_local_oob.rs:LL:CC
    |
 LL |     let _val = unsafe { *x };
-   |                         ^^ memory access failed: attempting to access 1 byte, but got ALLOC which is at or beyond the end of the allocation of size 0 bytes
+   |                         ^^ Undefined Behavior occurred here
    |
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
diff --git a/src/tools/miri/tests/native-lib/fail/function_not_in_so.stderr b/src/tools/miri/tests/native-lib/fail/function_not_in_so.stderr
index b663fd41457..632696e8249 100644
--- a/src/tools/miri/tests/native-lib/fail/function_not_in_so.stderr
+++ b/src/tools/miri/tests/native-lib/fail/function_not_in_so.stderr
@@ -2,7 +2,7 @@ error: unsupported operation: can't call foreign function `foo` on $OS
   --> tests/native-lib/fail/function_not_in_so.rs:LL:CC
    |
 LL |         foo();
-   |         ^^^^^ can't call foreign function `foo` on $OS
+   |         ^^^^^ unsupported operation occurred here
    |
    = help: this means the program tried to do something Miri does not support; it does not indicate a bug in the program
    = note: BACKTRACE:
diff --git a/src/tools/miri/tests/native-lib/fail/private_function.stderr b/src/tools/miri/tests/native-lib/fail/private_function.stderr
index 03681240015..9b32d0c381b 100644
--- a/src/tools/miri/tests/native-lib/fail/private_function.stderr
+++ b/src/tools/miri/tests/native-lib/fail/private_function.stderr
@@ -2,7 +2,7 @@ error: unsupported operation: can't call foreign function `not_exported` on $OS
   --> tests/native-lib/fail/private_function.rs:LL:CC
    |
 LL |         not_exported();
-   |         ^^^^^^^^^^^^^^ can't call foreign function `not_exported` on $OS
+   |         ^^^^^^^^^^^^^^ unsupported operation occurred here
    |
    = help: this means the program tried to do something Miri does not support; it does not indicate a bug in the program
    = note: BACKTRACE:
diff --git a/src/tools/miri/tests/native-lib/pass/ptr_read_access.stderr b/src/tools/miri/tests/native-lib/pass/ptr_read_access.stderr
index ab40811a9d1..04a3025baef 100644
--- a/src/tools/miri/tests/native-lib/pass/ptr_read_access.stderr
+++ b/src/tools/miri/tests/native-lib/pass/ptr_read_access.stderr
@@ -1,8 +1,8 @@
-warning: sharing memory with a native function
+warning: sharing memory with a native function called via FFI
   --> tests/native-lib/pass/ptr_read_access.rs:LL:CC
    |
 LL |     unsafe { print_pointer(&x) };
-   |              ^^^^^^^^^^^^^^^^^ sharing memory with a native function called via FFI
+   |              ^^^^^^^^^^^^^^^^^ sharing memory with a native function
    |
    = help: when memory is shared with a native function call, Miri stops tracking initialization and provenance for that memory
    = help: in particular, Miri assumes that the native call initializes all memory it has access to
diff --git a/src/tools/miri/tests/native-lib/pass/ptr_write_access.stderr b/src/tools/miri/tests/native-lib/pass/ptr_write_access.stderr
index a059d7740ff..c893b0d9f65 100644
--- a/src/tools/miri/tests/native-lib/pass/ptr_write_access.stderr
+++ b/src/tools/miri/tests/native-lib/pass/ptr_write_access.stderr
@@ -1,8 +1,8 @@
-warning: sharing memory with a native function
+warning: sharing memory with a native function called via FFI
   --> tests/native-lib/pass/ptr_write_access.rs:LL:CC
    |
 LL |     unsafe { increment_int(&mut x) };
-   |              ^^^^^^^^^^^^^^^^^^^^^ sharing memory with a native function called via FFI
+   |              ^^^^^^^^^^^^^^^^^^^^^ sharing memory with a native function
    |
    = help: when memory is shared with a native function call, Miri stops tracking initialization and provenance for that memory
    = help: in particular, Miri assumes that the native call initializes all memory it has access to
diff --git a/src/tools/miri/tests/pass-dep/libc/libc-fs.rs b/src/tools/miri/tests/pass-dep/libc/libc-fs.rs
index 129b18d8e59..0ff48c389e8 100644
--- a/src/tools/miri/tests/pass-dep/libc/libc-fs.rs
+++ b/src/tools/miri/tests/pass-dep/libc/libc-fs.rs
@@ -88,16 +88,17 @@ fn test_dup() {
     let name_ptr = name.as_bytes().as_ptr().cast::<libc::c_char>();
     unsafe {
         let fd = libc::open(name_ptr, libc::O_RDONLY);
+        let new_fd = libc::dup(fd);
+        let new_fd2 = libc::dup2(fd, 8);
+
         let mut first_buf = [0u8; 4];
         libc::read(fd, first_buf.as_mut_ptr() as *mut libc::c_void, 4);
         assert_eq!(&first_buf, b"dup ");
 
-        let new_fd = libc::dup(fd);
         let mut second_buf = [0u8; 4];
         libc::read(new_fd, second_buf.as_mut_ptr() as *mut libc::c_void, 4);
         assert_eq!(&second_buf, b"and ");
 
-        let new_fd2 = libc::dup2(fd, 8);
         let mut third_buf = [0u8; 4];
         libc::read(new_fd2, third_buf.as_mut_ptr() as *mut libc::c_void, 4);
         assert_eq!(&third_buf, b"dup2");
diff --git a/src/tools/miri/tests/pass/alloc-access-tracking.stderr b/src/tools/miri/tests/pass/alloc-access-tracking.stderr
index 0c85afd831b..af124776402 100644
--- a/src/tools/miri/tests/pass/alloc-access-tracking.stderr
+++ b/src/tools/miri/tests/pass/alloc-access-tracking.stderr
@@ -1,36 +1,36 @@
-note: tracking was triggered
+note: created Miri bare-metal heap allocation of 123 bytes (alignment ALIGN bytes) with id $ALLOC
   --> tests/pass/alloc-access-tracking.rs:LL:CC
    |
 LL |         let ptr = miri_alloc(123, 1);
-   |                   ^^^^^^^^^^^^^^^^^^ created Miri bare-metal heap allocation of 123 bytes (alignment ALIGN bytes) with id $ALLOC
+   |                   ^^^^^^^^^^^^^^^^^^ tracking was triggered here
    |
    = note: BACKTRACE:
    = note: inside `miri_start` at tests/pass/alloc-access-tracking.rs:LL:CC
 
-note: tracking was triggered
+note: write access to allocation with id $ALLOC
   --> tests/pass/alloc-access-tracking.rs:LL:CC
    |
 LL |         *ptr = 42; // Crucially, only a write is printed here, no read!
-   |         ^^^^^^^^^ write access to allocation with id $ALLOC
+   |         ^^^^^^^^^ tracking was triggered here
    |
    = note: BACKTRACE:
    = note: inside `miri_start` at tests/pass/alloc-access-tracking.rs:LL:CC
 
-note: tracking was triggered
+note: read access to allocation with id $ALLOC
   --> tests/pass/alloc-access-tracking.rs:LL:CC
    |
 LL |         assert_eq!(*ptr, 42);
-   |         ^^^^^^^^^^^^^^^^^^^^ read access to allocation with id $ALLOC
+   |         ^^^^^^^^^^^^^^^^^^^^ tracking was triggered here
    |
    = note: BACKTRACE:
    = note: inside `miri_start` at RUSTLIB/core/src/macros/mod.rs:LL:CC
    = note: this note originates in the macro `assert_eq` (in Nightly builds, run with -Z macro-backtrace for more info)
 
-note: tracking was triggered
+note: freed allocation with id $ALLOC
   --> tests/pass/alloc-access-tracking.rs:LL:CC
    |
 LL |         miri_dealloc(ptr, 123, 1);
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^ freed allocation with id $ALLOC
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^ tracking was triggered here
    |
    = note: BACKTRACE:
    = note: inside `miri_start` at tests/pass/alloc-access-tracking.rs:LL:CC
diff --git a/src/tools/miri/tests/pass/both_borrows/smallvec.rs b/src/tools/miri/tests/pass/both_borrows/smallvec.rs
new file mode 100644
index 00000000000..f48815e37be
--- /dev/null
+++ b/src/tools/miri/tests/pass/both_borrows/smallvec.rs
@@ -0,0 +1,99 @@
+//! This test represents a core part of `SmallVec`'s `extend_impl`.
+//! What makes it interesting as a test is that it relies on Stacked Borrow's "quirk"
+//! in a fundamental, hard-to-fix-without-full-trees way.
+
+//@revisions: stack tree
+//@[tree]compile-flags: -Zmiri-tree-borrows
+
+use std::marker::PhantomData;
+use std::mem::{ManuallyDrop, MaybeUninit};
+use std::ptr::NonNull;
+
+#[repr(C)]
+pub union RawSmallVec<T, const N: usize> {
+    inline: ManuallyDrop<MaybeUninit<[T; N]>>,
+    heap: (NonNull<T>, usize),
+}
+
+impl<T, const N: usize> RawSmallVec<T, N> {
+    const fn new() -> Self {
+        Self::new_inline(MaybeUninit::uninit())
+    }
+
+    const fn new_inline(inline: MaybeUninit<[T; N]>) -> Self {
+        Self { inline: ManuallyDrop::new(inline) }
+    }
+
+    const fn as_mut_ptr_inline(&mut self) -> *mut T {
+        (unsafe { &raw mut self.inline }) as *mut T
+    }
+
+    const unsafe fn as_mut_ptr_heap(&mut self) -> *mut T {
+        self.heap.0.as_ptr()
+    }
+}
+
+#[repr(transparent)]
+#[derive(Clone, Copy)]
+struct TaggedLen(usize);
+
+impl TaggedLen {
+    pub const fn new(len: usize, on_heap: bool, is_zst: bool) -> Self {
+        if is_zst {
+            debug_assert!(!on_heap);
+            TaggedLen(len)
+        } else {
+            debug_assert!(len < isize::MAX as usize);
+            TaggedLen((len << 1) | on_heap as usize)
+        }
+    }
+
+    pub const fn on_heap(self, is_zst: bool) -> bool {
+        if is_zst { false } else { (self.0 & 1_usize) == 1 }
+    }
+
+    pub const fn value(self, is_zst: bool) -> usize {
+        if is_zst { self.0 } else { self.0 >> 1 }
+    }
+}
+
+#[repr(C)]
+pub struct SmallVec<T, const N: usize> {
+    len: TaggedLen,
+    raw: RawSmallVec<T, N>,
+    _marker: PhantomData<T>,
+}
+
+impl<T, const N: usize> SmallVec<T, N> {
+    pub const fn new() -> SmallVec<T, N> {
+        Self {
+            len: TaggedLen::new(0, false, Self::is_zst()),
+            raw: RawSmallVec::new(),
+            _marker: PhantomData,
+        }
+    }
+
+    const fn is_zst() -> bool {
+        size_of::<T>() == 0
+    }
+
+    pub const fn as_mut_ptr(&mut self) -> *mut T {
+        if self.len.on_heap(Self::is_zst()) {
+            // SAFETY: see above
+            unsafe { self.raw.as_mut_ptr_heap() }
+        } else {
+            self.raw.as_mut_ptr_inline()
+        }
+    }
+
+    pub const fn len(&self) -> usize {
+        self.len.value(Self::is_zst())
+    }
+}
+
+fn main() {
+    let mut v = SmallVec::<i32, 4>::new();
+    let ptr = v.as_mut_ptr();
+    let _len = v.len(); // this call incurs a reborrow which just barely does not invalidate `ptr`
+    unsafe { ptr.write(0) };
+}
diff --git a/src/tools/miri/tests/pass/extern_types.stack.stderr b/src/tools/miri/tests/pass/extern_types.stack.stderr
index 898c19d514b..bd51efeb3e3 100644
--- a/src/tools/miri/tests/pass/extern_types.stack.stderr
+++ b/src/tools/miri/tests/pass/extern_types.stack.stderr
@@ -1,8 +1,8 @@
-warning: reborrow of reference to `extern type`
+warning: reborrow of a reference to `extern type` is not properly supported
   --> tests/pass/extern_types.rs:LL:CC
    |
 LL |     let x: &Foo = unsafe { &*(ptr::without_provenance::<()>(16) as *const Foo) };
-   |                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ reborrow of a reference to `extern type` is not properly supported
+   |                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ reborrow of reference to `extern type`
    |
    = help: `extern type` are not compatible with the Stacked Borrows aliasing model implemented by Miri; Miri may miss bugs in this code
    = help: try running with `MIRIFLAGS=-Zmiri-tree-borrows` to use the more permissive but also even more experimental Tree Borrows aliasing checks instead
diff --git a/src/tools/miri/tests/pass/float.rs b/src/tools/miri/tests/pass/float.rs
index 98a88cfd62d..383579198bb 100644
--- a/src/tools/miri/tests/pass/float.rs
+++ b/src/tools/miri/tests/pass/float.rs
@@ -45,6 +45,30 @@ macro_rules! assert_approx_eq {
     };
 }
 
+/// From IEEE 754 a Signaling NaN for single precision has the following representation:
+/// ```
+/// s | 1111 1111 | 0x..x
+/// ````
+/// Were at least one `x` is a 1.
+///
+/// This sNaN has the following representation and is used for testing purposes.:
+/// ```
+/// 0 | 1111111 | 01..0
+/// ```
+const SNAN_F32: f32 = f32::from_bits(0x7fa00000);
+
+/// From IEEE 754 a Signaling NaN for double precision has the following representation:
+/// ```
+/// s | 1111 1111 111 | 0x..x
+/// ````
+/// Were at least one `x` is a 1.
+///
+/// This sNaN has the following representation and is used for testing purposes.:
+/// ```
+/// 0 | 1111 1111 111 | 01..0
+/// ```
+const SNAN_F64: f64 = f64::from_bits(0x7ff4000000000000);
+
 fn main() {
     basic();
     casts();
@@ -1008,17 +1032,84 @@ pub fn libm() {
     assert_approx_eq!(25f32.powf(-2f32), 0.0016f32);
     assert_approx_eq!(400f64.powf(0.5f64), 20f64);
 
+    // Some inputs to powf and powi result in fixed outputs
+    // and thus must be exactly equal to that value.
+    // C standard says:
+    // 1^y = 1 for any y, even a NaN.
+    assert_eq!(1f32.powf(10.0), 1.0);
+    assert_eq!(1f64.powf(100.0), 1.0);
+    assert_eq!(1f32.powf(f32::INFINITY), 1.0);
+    assert_eq!(1f64.powf(f64::INFINITY), 1.0);
+    assert_eq!(1f32.powf(f32::NAN), 1.0);
+    assert_eq!(1f64.powf(f64::NAN), 1.0);
+
+    // f*::NAN is a quiet NAN and should return 1 as well.
+    assert_eq!(f32::NAN.powf(0.0), 1.0);
+    assert_eq!(f64::NAN.powf(0.0), 1.0);
+
+    assert_eq!(42f32.powf(0.0), 1.0);
+    assert_eq!(42f64.powf(0.0), 1.0);
+    assert_eq!(f32::INFINITY.powf(0.0), 1.0);
+    assert_eq!(f64::INFINITY.powf(0.0), 1.0);
+
+    // f*::NAN is a quiet NAN and should return 1 as well.
+    assert_eq!(f32::NAN.powi(0), 1.0);
+    assert_eq!(f64::NAN.powi(0), 1.0);
+
+    assert_eq!(10.0f32.powi(0), 1.0);
+    assert_eq!(10.0f64.powi(0), 1.0);
+    assert_eq!(f32::INFINITY.powi(0), 1.0);
+    assert_eq!(f64::INFINITY.powi(0), 1.0);
+
+    assert_eq!((-1f32).powf(f32::INFINITY), 1.0);
+    assert_eq!((-1f64).powf(f64::INFINITY), 1.0);
+    assert_eq!((-1f32).powf(f32::NEG_INFINITY), 1.0);
+    assert_eq!((-1f64).powf(f64::NEG_INFINITY), 1.0);
+
+    // For pow (powf in rust) the C standard says:
+    // x^0 = 1 for all x even a sNaN
+    // FIXME(#4286): this does not match the behavior of all implementations.
+    assert_eq!(SNAN_F32.powf(0.0), 1.0);
+    assert_eq!(SNAN_F64.powf(0.0), 1.0);
+
+    // For pown (powi in rust) the C standard says:
+    // x^0 = 1 for all x even a sNaN
+    // FIXME(#4286): this does not match the behavior of all implementations.
+    assert_eq!(SNAN_F32.powi(0), 1.0);
+    assert_eq!(SNAN_F64.powi(0), 1.0);
+
+    assert_eq!(0f32.powi(10), 0.0);
+    assert_eq!(0f64.powi(100), 0.0);
+    assert_eq!(0f32.powi(9), 0.0);
+    assert_eq!(0f64.powi(99), 0.0);
+
+    assert_biteq((-0f32).powf(10.0), 0.0, "-0^x = +0 where x is positive");
+    assert_biteq((-0f64).powf(100.0), 0.0, "-0^x = +0 where x is positive");
+    assert_biteq((-0f32).powf(9.0), -0.0, "-0^x = -0 where x is negative");
+    assert_biteq((-0f64).powf(99.0), -0.0, "-0^x = -0 where x is negative");
+
+    assert_biteq((-0f32).powi(10), 0.0, "-0^x = +0 where x is positive");
+    assert_biteq((-0f64).powi(100), 0.0, "-0^x = +0 where x is positive");
+    assert_biteq((-0f32).powi(9), -0.0, "-0^x = -0 where x is negative");
+    assert_biteq((-0f64).powi(99), -0.0, "-0^x = -0 where x is negative");
+
     assert_approx_eq!(1f32.exp(), f32::consts::E);
     assert_approx_eq!(1f64.exp(), f64::consts::E);
+    assert_eq!(0f32.exp(), 1.0);
+    assert_eq!(0f64.exp(), 1.0);
 
     assert_approx_eq!(1f32.exp_m1(), f32::consts::E - 1.0);
     assert_approx_eq!(1f64.exp_m1(), f64::consts::E - 1.0);
 
     assert_approx_eq!(10f32.exp2(), 1024f32);
     assert_approx_eq!(50f64.exp2(), 1125899906842624f64);
+    assert_eq!(0f32.exp2(), 1.0);
+    assert_eq!(0f64.exp2(), 1.0);
 
     assert_approx_eq!(f32::consts::E.ln(), 1f32);
-    assert_approx_eq!(1f64.ln(), 0f64);
+    assert_approx_eq!(f64::consts::E.ln(), 1f64);
+    assert_eq!(1f32.ln(), 0.0);
+    assert_eq!(1f64.ln(), 0.0);
 
     assert_approx_eq!(0f32.ln_1p(), 0f32);
     assert_approx_eq!(0f64.ln_1p(), 0f64);
@@ -1047,7 +1138,8 @@ pub fn libm() {
 
     // Trigonometric functions.
 
-    assert_approx_eq!(0f32.sin(), 0f32);
+    assert_eq!(0f32.sin(), 0f32);
+    assert_eq!(0f64.sin(), 0f64);
     assert_approx_eq!((f64::consts::PI / 2f64).sin(), 1f64);
     assert_approx_eq!(f32::consts::FRAC_PI_6.sin(), 0.5);
     assert_approx_eq!(f64::consts::FRAC_PI_6.sin(), 0.5);
@@ -1059,7 +1151,23 @@ pub fn libm() {
     assert_approx_eq!(2.0f32.asinh(), 1.443635475178810342493276740273105f32);
     assert_approx_eq!((-2.0f64).asinh(), -1.443635475178810342493276740273105f64);
 
-    assert_approx_eq!(0f32.cos(), 1f32);
+    // Ensure `sin` always returns something that is a valid input for `asin`, and same for
+    // `cos` and `acos`.
+    let halve_pi_f32 = std::f32::consts::FRAC_PI_2;
+    let halve_pi_f64 = std::f64::consts::FRAC_PI_2;
+    let pi_f32 = std::f32::consts::PI;
+    let pi_f64 = std::f64::consts::PI;
+    for _ in 0..64 {
+        // sin() should be clamped to [-1, 1] so asin() can never return NaN
+        assert!(!halve_pi_f32.sin().asin().is_nan());
+        assert!(!halve_pi_f64.sin().asin().is_nan());
+        // cos() should be clamped to [-1, 1] so acos() can never return NaN
+        assert!(!pi_f32.cos().acos().is_nan());
+        assert!(!pi_f64.cos().acos().is_nan());
+    }
+
+    assert_eq!(0f32.cos(), 1f32);
+    assert_eq!(0f64.cos(), 1f64);
     assert_approx_eq!((f64::consts::PI * 2f64).cos(), 1f64);
     assert_approx_eq!(f32::consts::FRAC_PI_3.cos(), 0.5);
     assert_approx_eq!(f64::consts::FRAC_PI_3.cos(), 0.5);
@@ -1278,7 +1386,6 @@ fn test_non_determinism() {
         frem_algebraic, frem_fast, fsub_algebraic, fsub_fast,
     };
     use std::{f32, f64};
-    // TODO: Also test powi and powf when the non-determinism is implemented for them
 
     /// Ensure that the operation is non-deterministic
     #[track_caller]
@@ -1318,21 +1425,23 @@ fn test_non_determinism() {
     }
     pub fn test_operations_f32(a: f32, b: f32) {
         test_operations_f!(a, b);
-        // FIXME: temporarily disabled as it breaks std tests.
-        // ensure_nondet(|| a.log(b));
-        // ensure_nondet(|| a.exp());
-        // ensure_nondet(|| 10f32.exp2());
-        // ensure_nondet(|| f32::consts::E.ln());
+        // FIXME: some are temporarily disabled as it breaks std tests.
+        ensure_nondet(|| a.powf(b));
+        ensure_nondet(|| a.powi(2));
+        ensure_nondet(|| a.log(b));
+        ensure_nondet(|| a.exp());
+        ensure_nondet(|| 10f32.exp2());
+        ensure_nondet(|| f32::consts::E.ln());
+        ensure_nondet(|| 10f32.log10());
+        ensure_nondet(|| 8f32.log2());
         // ensure_nondet(|| 1f32.ln_1p());
-        // ensure_nondet(|| 10f32.log10());
-        // ensure_nondet(|| 8f32.log2());
         // ensure_nondet(|| 27.0f32.cbrt());
         // ensure_nondet(|| 3.0f32.hypot(4.0f32));
-        // ensure_nondet(|| 1f32.sin());
-        // ensure_nondet(|| 0f32.cos());
-        // // On i686-pc-windows-msvc , these functions are implemented by calling the `f64` version,
-        // // which means the little rounding errors Miri introduces are discard by the cast down to `f32`.
-        // // Just skip the test for them.
+        ensure_nondet(|| 1f32.sin());
+        ensure_nondet(|| 1f32.cos());
+        // On i686-pc-windows-msvc , these functions are implemented by calling the `f64` version,
+        // which means the little rounding errors Miri introduces are discarded by the cast down to
+        // `f32`. Just skip the test for them.
         // if !cfg!(all(target_os = "windows", target_env = "msvc", target_arch = "x86")) {
         //     ensure_nondet(|| 1.0f32.tan());
         //     ensure_nondet(|| 1.0f32.asin());
@@ -1353,18 +1462,20 @@ fn test_non_determinism() {
     }
     pub fn test_operations_f64(a: f64, b: f64) {
         test_operations_f!(a, b);
-        // FIXME: temporarily disabled as it breaks std tests.
-        // ensure_nondet(|| a.log(b));
-        // ensure_nondet(|| a.exp());
-        // ensure_nondet(|| 50f64.exp2());
-        // ensure_nondet(|| 3f64.ln());
+        // FIXME: some are temporarily disabled as it breaks std tests.
+        ensure_nondet(|| a.powf(b));
+        ensure_nondet(|| a.powi(2));
+        ensure_nondet(|| a.log(b));
+        ensure_nondet(|| a.exp());
+        ensure_nondet(|| 50f64.exp2());
+        ensure_nondet(|| 3f64.ln());
+        ensure_nondet(|| f64::consts::E.log10());
+        ensure_nondet(|| f64::consts::E.log2());
         // ensure_nondet(|| 1f64.ln_1p());
-        // ensure_nondet(|| f64::consts::E.log10());
-        // ensure_nondet(|| f64::consts::E.log2());
         // ensure_nondet(|| 27.0f64.cbrt());
         // ensure_nondet(|| 3.0f64.hypot(4.0f64));
-        // ensure_nondet(|| 1f64.sin());
-        // ensure_nondet(|| 0f64.cos());
+        ensure_nondet(|| 1f64.sin());
+        ensure_nondet(|| 1f64.cos());
         // ensure_nondet(|| 1.0f64.tan());
         // ensure_nondet(|| 1.0f64.asin());
         // ensure_nondet(|| 5.0f64.acos());
diff --git a/src/tools/miri/tests/pass/shims/fs.rs b/src/tools/miri/tests/pass/shims/fs.rs
index 87df43ca7e5..9d5725773e6 100644
--- a/src/tools/miri/tests/pass/shims/fs.rs
+++ b/src/tools/miri/tests/pass/shims/fs.rs
@@ -6,8 +6,7 @@
 use std::collections::BTreeMap;
 use std::ffi::OsString;
 use std::fs::{
-    File, OpenOptions, canonicalize, create_dir, read_dir, remove_dir, remove_dir_all, remove_file,
-    rename,
+    self, File, OpenOptions, create_dir, read_dir, remove_dir, remove_dir_all, remove_file, rename,
 };
 use std::io::{Error, ErrorKind, IsTerminal, Read, Result, Seek, SeekFrom, Write};
 use std::path::Path;
@@ -33,6 +32,8 @@ fn main() {
         test_canonicalize();
         #[cfg(unix)]
         test_pread_pwrite();
+        #[cfg(not(any(target_os = "solaris", target_os = "illumos")))]
+        test_flock();
     }
 }
 
@@ -240,7 +241,7 @@ fn test_canonicalize() {
     let path = dir_path.join("test_file");
     drop(File::create(&path).unwrap());
 
-    let p = canonicalize(format!("{}/./test_file", dir_path.to_string_lossy())).unwrap();
+    let p = fs::canonicalize(format!("{}/./test_file", dir_path.to_string_lossy())).unwrap();
     assert_eq!(p.to_string_lossy().find("/./"), None);
 
     remove_dir_all(&dir_path).unwrap();
@@ -351,3 +352,28 @@ fn test_pread_pwrite() {
     f.read_exact(&mut buf1).unwrap();
     assert_eq!(&buf1, b"  m");
 }
+
+// This function does seem to exist on Illumos but std does not expose it there.
+#[cfg(not(any(target_os = "solaris", target_os = "illumos")))]
+fn test_flock() {
+    let bytes = b"Hello, World!\n";
+    let path = utils::prepare_with_content("miri_test_fs_flock.txt", bytes);
+    let file1 = OpenOptions::new().read(true).write(true).open(&path).unwrap();
+    let file2 = OpenOptions::new().read(true).write(true).open(&path).unwrap();
+
+    // Test that we can apply many shared locks
+    file1.lock_shared().unwrap();
+    file2.lock_shared().unwrap();
+    // Test that shared lock prevents exclusive lock
+    assert!(matches!(file1.try_lock().unwrap_err(), fs::TryLockError::WouldBlock));
+    // Unlock shared lock
+    file1.unlock().unwrap();
+    file2.unlock().unwrap();
+    // Take exclusive lock
+    file1.lock().unwrap();
+    // Test that shared lock prevents exclusive and shared locks
+    assert!(matches!(file2.try_lock().unwrap_err(), fs::TryLockError::WouldBlock));
+    assert!(matches!(file2.try_lock_shared().unwrap_err(), fs::TryLockError::WouldBlock));
+    // Unlock exclusive lock
+    file1.unlock().unwrap();
+}
diff --git a/src/tools/miri/tests/pass/tree_borrows/cell-inside-struct.rs b/src/tools/miri/tests/pass/tree_borrows/cell-inside-struct.rs
new file mode 100644
index 00000000000..fd68685a2f4
--- /dev/null
+++ b/src/tools/miri/tests/pass/tree_borrows/cell-inside-struct.rs
@@ -0,0 +1,34 @@
+//! The same as `tests/fail/tree-borrows/cell-inside-struct` but with
+//! precise tracking of interior mutability disabled.
+//@compile-flags: -Zmiri-tree-borrows -Zmiri-tree-borrows-no-precise-interior-mut
+#[path = "../../utils/mod.rs"]
+#[macro_use]
+mod utils;
+
+use std::cell::Cell;
+
+struct Foo {
+    field1: u32,
+    field2: Cell<u32>,
+}
+
+pub fn main() {
+    let root = Foo { field1: 42, field2: Cell::new(88) };
+    unsafe {
+        let a = &root;
+
+        name!(a as *const Foo, "a");
+
+        let a: *const Foo = a as *const Foo;
+        let a: *mut Foo = a as *mut Foo;
+
+        let alloc_id = alloc_id!(a);
+        print_state!(alloc_id);
+
+        // Writing to `field2`, which is interior mutable, should be allowed.
+        (*a).field2.set(10);
+
+        // Writing to `field1` should be allowed because it also has the `Cell` permission.
+        (*a).field1 = 88;
+    }
+}
diff --git a/src/tools/miri/tests/pass/tree_borrows/cell-inside-struct.stderr b/src/tools/miri/tests/pass/tree_borrows/cell-inside-struct.stderr
new file mode 100644
index 00000000000..1d939329040
--- /dev/null
+++ b/src/tools/miri/tests/pass/tree_borrows/cell-inside-struct.stderr
@@ -0,0 +1,6 @@
+──────────────────────────────────────────────────
+Warning: this tree is indicative only. Some tags may have been hidden.
+0..   8
+| Act |    └─┬──<TAG=root of the allocation>
+|?Cel |      └────<TAG=a>
+──────────────────────────────────────────────────
diff --git a/src/tools/rust-analyzer/Cargo.lock b/src/tools/rust-analyzer/Cargo.lock
index c2b4e21483e..2c7b4641641 100644
--- a/src/tools/rust-analyzer/Cargo.lock
+++ b/src/tools/rust-analyzer/Cargo.lock
@@ -60,7 +60,7 @@ dependencies = [
  "cfg-if",
  "libc",
  "miniz_oxide",
- "object 0.36.7",
+ "object",
  "rustc-demangle",
  "windows-targets 0.52.6",
 ]
@@ -1401,15 +1401,6 @@ dependencies = [
 ]
 
 [[package]]
-name = "object"
-version = "0.37.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "03fd943161069e1768b4b3d050890ba48730e590f57e56d4aa04e7e090e61b4a"
-dependencies = [
- "memchr",
-]
-
-[[package]]
 name = "once_cell"
 version = "1.21.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -1573,7 +1564,7 @@ dependencies = [
  "libc",
  "libloading",
  "memmap2",
- "object 0.37.1",
+ "object",
  "paths",
  "proc-macro-test",
  "ra-ap-rustc_lexer",
diff --git a/src/tools/rust-analyzer/Cargo.toml b/src/tools/rust-analyzer/Cargo.toml
index c791d741b02..449c75859cf 100644
--- a/src/tools/rust-analyzer/Cargo.toml
+++ b/src/tools/rust-analyzer/Cargo.toml
@@ -122,7 +122,7 @@ libloading = "0.8.8"
 memmap2 = "0.9.5"
 nohash-hasher = "0.2.0"
 oorandom = "11.1.5"
-object = { version = "0.37.1", default-features = false, features = [
+object = { version = "0.36.7", default-features = false, features = [
   "std",
   "read_core",
   "elf",
diff --git a/src/tools/rust-analyzer/crates/hir-expand/src/inert_attr_macro.rs b/src/tools/rust-analyzer/crates/hir-expand/src/inert_attr_macro.rs
index 543ac0619dd..385c98ef877 100644
--- a/src/tools/rust-analyzer/crates/hir-expand/src/inert_attr_macro.rs
+++ b/src/tools/rust-analyzer/crates/hir-expand/src/inert_attr_macro.rs
@@ -486,7 +486,7 @@ pub const INERT_ATTRIBUTES: &[BuiltinAttribute] = &[
         rustc_legacy_const_generics, Normal, template!(List: "N"), ErrorFollowing,
         INTERNAL_UNSTABLE
     ),
-    // Do not const-check this function's body. It will always get replaced during CTFE.
+    // Do not const-check this function's body. It will always get replaced during CTFE via `hook_special_const_fn`.
     rustc_attr!(
         rustc_do_not_const_check, Normal, template!(Word), WarnFollowing, INTERNAL_UNSTABLE
     ),
diff --git a/src/tools/rustbook/Cargo.lock b/src/tools/rustbook/Cargo.lock
index 8893846b5fa..ed67fa7d1a9 100644
--- a/src/tools/rustbook/Cargo.lock
+++ b/src/tools/rustbook/Cargo.lock
@@ -47,9 +47,9 @@ dependencies = [
 
 [[package]]
 name = "anstream"
-version = "0.6.18"
+version = "0.6.19"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8acc5369981196006228e28809f761875c0327210a891e941f4c683b3a99529b"
+checksum = "301af1932e46185686725e0fad2f8f2aa7da69dd70bf6ecc44d6b703844a3933"
 dependencies = [
  "anstyle",
  "anstyle-parse",
@@ -62,36 +62,36 @@ dependencies = [
 
 [[package]]
 name = "anstyle"
-version = "1.0.10"
+version = "1.0.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "55cc3b69f167a1ef2e161439aa98aed94e6028e5f9a59be9a6ffb47aef1651f9"
+checksum = "862ed96ca487e809f1c8e5a8447f6ee2cf102f846893800b20cebdf541fc6bbd"
 
 [[package]]
 name = "anstyle-parse"
-version = "0.2.6"
+version = "0.2.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3b2d16507662817a6a20a9ea92df6652ee4f94f914589377d69f3b21bc5798a9"
+checksum = "4e7644824f0aa2c7b9384579234ef10eb7efb6a0deb83f9630a49594dd9c15c2"
 dependencies = [
  "utf8parse",
 ]
 
 [[package]]
 name = "anstyle-query"
-version = "1.1.2"
+version = "1.1.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "79947af37f4177cfead1110013d678905c37501914fba0efea834c3fe9a8d60c"
+checksum = "6c8bdeb6047d8983be085bab0ba1472e6dc604e7041dbf6fcd5e71523014fae9"
 dependencies = [
  "windows-sys",
 ]
 
 [[package]]
 name = "anstyle-wincon"
-version = "3.0.7"
+version = "3.0.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ca3534e77181a9cc07539ad51f2141fe32f6c3ffd4df76db8ad92346b003ae4e"
+checksum = "403f75924867bb1033c59fbf0797484329750cfbe3c4325cd33127941fabc882"
 dependencies = [
  "anstyle",
- "once_cell",
+ "once_cell_polyfill",
  "windows-sys",
 ]
 
@@ -124,9 +124,9 @@ checksum = "bef38d45163c2f1dde094a7dfd33ccf595c92905c8f8f4fdc18d06fb1037718a"
 
 [[package]]
 name = "bitflags"
-version = "2.9.0"
+version = "2.9.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5c8214115b7bf84099f1309324e63141d4c5d7cc26862f97a0a857dbefe165bd"
+checksum = "1b8e56985ec62d17e9c1001dc89c88ecd7dc08e47eba5ec7c29c7b5eeecde967"
 
 [[package]]
 name = "block-buffer"
@@ -150,15 +150,15 @@ dependencies = [
 
 [[package]]
 name = "bumpalo"
-version = "3.17.0"
+version = "3.18.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1628fb46dfa0b37568d12e5edd512553eccf6a22a78e8bde00bb4aed84d5bdbf"
+checksum = "793db76d6187cd04dff33004d8e6c9cc4e05cd330500379d2394209271b4aeee"
 
 [[package]]
 name = "cc"
-version = "1.2.22"
+version = "1.2.26"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "32db95edf998450acc7881c932f94cd9b05c87b4b2599e8bab064753da4acfd1"
+checksum = "956a5e21988b87f372569b66183b78babf23ebc2e744b733e4350a752c4dafac"
 dependencies = [
  "shlex",
 ]
@@ -185,9 +185,9 @@ dependencies = [
 
 [[package]]
 name = "clap"
-version = "4.5.38"
+version = "4.5.39"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ed93b9805f8ba930df42c2590f05453d5ec36cbb85d018868a5b24d31f6ac000"
+checksum = "fd60e63e9be68e5fb56422e397cf9baddded06dae1d2e523401542383bc72a9f"
 dependencies = [
  "clap_builder",
  "clap_derive",
@@ -195,9 +195,9 @@ dependencies = [
 
 [[package]]
 name = "clap_builder"
-version = "4.5.38"
+version = "4.5.39"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "379026ff283facf611b0ea629334361c4211d1b12ee01024eec1591133b04120"
+checksum = "89cc6392a1f72bbeb820d71f32108f61fdaf18bc526e1d23954168a67759ef51"
 dependencies = [
  "anstream",
  "anstyle",
@@ -208,9 +208,9 @@ dependencies = [
 
 [[package]]
 name = "clap_complete"
-version = "4.5.50"
+version = "4.5.52"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c91d3baa3bcd889d60e6ef28874126a0b384fd225ab83aa6d8a801c519194ce1"
+checksum = "1a554639e42d0c838336fc4fbedb9e2df3ad1fa4acda149f9126b4ccfcd7900f"
 dependencies = [
  "clap",
 ]
@@ -235,9 +235,9 @@ checksum = "f46ad14479a25103f283c0f10005961cf086d8dc42205bb44c46ac563475dca6"
 
 [[package]]
 name = "colorchoice"
-version = "1.0.3"
+version = "1.0.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5b63caa9aa9397e2d9480a9b13673856c78d8ac123288526c37d7839f2a86990"
+checksum = "b05b61dc5112cbb17e4b6cd61790d9845d13888356391624cbe7e41efeac1e75"
 
 [[package]]
 name = "core-foundation-sys"
@@ -459,9 +459,9 @@ checksum = "877a4ace8713b0bcf2a4e7eec82529c029f1d0619886d18145fea96c3ffe5c0f"
 
 [[package]]
 name = "errno"
-version = "0.3.11"
+version = "0.3.12"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "976dd42dc7e85965fe702eb8164f21f450704bdde31faefd6471dba214cb594e"
+checksum = "cea14ef9355e3beab063703aa9dab15afd25f0667c341310c1e5274bb1d0da18"
 dependencies = [
  "libc",
  "windows-sys",
@@ -482,9 +482,9 @@ checksum = "37909eebbb50d72f9059c3b6d82c0463f2ff062c9e95845c43a6c9c0355411be"
 
 [[package]]
 name = "flate2"
-version = "1.1.1"
+version = "1.1.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7ced92e76e966ca2fd84c8f7aa01a4aea65b0eb6648d72f7c8f3e2764a67fece"
+checksum = "4a3d7db9596fecd151c5f638c0ee5d5bd487b6e0ea232e5dc96d5250f6f94b1d"
 dependencies = [
  "crc32fast",
  "miniz_oxide",
@@ -531,7 +531,7 @@ version = "0.2.21"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "14dbbfd5c71d70241ecf9e6f13737f7b5ce823821063188d7e46c41d371eebd5"
 dependencies = [
- "unicode-width",
+ "unicode-width 0.1.14",
 ]
 
 [[package]]
@@ -564,9 +564,9 @@ dependencies = [
 
 [[package]]
 name = "hashbrown"
-version = "0.15.3"
+version = "0.15.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "84b26c544d002229e640969970a2e74021aadf6e2f96372b9c58eff97de08eb3"
+checksum = "5971ac85611da7067dbfcabef3c70ebb5606018acd9e2a3903a0da507521e0d5"
 
 [[package]]
 name = "heck"
@@ -680,9 +680,9 @@ checksum = "00210d6893afc98edb752b664b8890f0ef174c8adbb8d0be9710fa66fbbf72d3"
 
 [[package]]
 name = "icu_properties"
-version = "2.0.0"
+version = "2.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2549ca8c7241c82f59c80ba2a6f415d931c5b58d24fb8412caa1a1f02c49139a"
+checksum = "016c619c1eeb94efb86809b015c58f479963de65bdb6253345c1a1276f22e32b"
 dependencies = [
  "displaydoc",
  "icu_collections",
@@ -696,9 +696,9 @@ dependencies = [
 
 [[package]]
 name = "icu_properties_data"
-version = "2.0.0"
+version = "2.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8197e866e47b68f8f7d95249e172903bec06004b18b2937f1095d40a0c57de04"
+checksum = "298459143998310acd25ffe6810ed544932242d3f07083eee1084d83a71bd632"
 
 [[package]]
 name = "icu_provider"
@@ -768,9 +768,9 @@ checksum = "4a5f13b858c8d314ee3e8f639011f7ccefe71f97f96e50151fb991f267928e2c"
 
 [[package]]
 name = "jiff"
-version = "0.2.13"
+version = "0.2.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f02000660d30638906021176af16b17498bd0d12813dbfe7b276d8bc7f3c0806"
+checksum = "a194df1107f33c79f4f93d02c80798520551949d59dfad22b6157048a88cca93"
 dependencies = [
  "jiff-static",
  "log",
@@ -781,9 +781,9 @@ dependencies = [
 
 [[package]]
 name = "jiff-static"
-version = "0.2.13"
+version = "0.2.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f3c30758ddd7188629c6713fc45d1188af4f44c90582311d0c8d8c9907f60c48"
+checksum = "6c6e1db7ed32c6c71b759497fae34bf7933636f75a251b9e736555da426f6442"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -835,9 +835,9 @@ checksum = "241eaef5fd12c88705a01fc1066c48c4b36e0dd4377dcdc7ec3942cea7a69956"
 
 [[package]]
 name = "lock_api"
-version = "0.4.12"
+version = "0.4.13"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "07af8b9cdd281b7915f413fa73f29ebd5d55d0d3f0155584dade1ff18cea1b17"
+checksum = "96936507f153605bddfcda068dd804796c84324ed2510809e5b2a624c81da765"
 dependencies = [
  "autocfg",
  "scopeguard",
@@ -961,7 +961,7 @@ dependencies = [
  "pulldown-cmark-to-cmark 19.0.1",
  "serde_json",
  "thiserror 1.0.69",
- "toml 0.8.22",
+ "toml 0.8.23",
 ]
 
 [[package]]
@@ -1025,12 +1025,18 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "42f5e15c9953c5e4ccceeb2e7382a716482c34515315f7b03532b8b4e8393d2d"
 
 [[package]]
+name = "once_cell_polyfill"
+version = "1.70.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a4895175b425cb1f87721b59f0f286c2092bd4af812243672510e1ac53e2e0ad"
+
+[[package]]
 name = "onig"
 version = "6.5.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "336b9c63443aceef14bea841b899035ae3abe89b7c486aaf4c5bd8aafedac3f0"
 dependencies = [
- "bitflags 2.9.0",
+ "bitflags 2.9.1",
  "libc",
  "once_cell",
  "onig_sys",
@@ -1048,9 +1054,9 @@ dependencies = [
 
 [[package]]
 name = "opener"
-version = "0.8.1"
+version = "0.8.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "de96cad6ee771be7f68df884d3767460b4684012308d8342ed5623fe62b2628c"
+checksum = "771b9704f8cd8b424ec747a320b30b47517a6966ba2c7da90047c16f4a962223"
 dependencies = [
  "bstr",
  "normpath",
@@ -1059,9 +1065,9 @@ dependencies = [
 
 [[package]]
 name = "parking_lot"
-version = "0.12.3"
+version = "0.12.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f1bf18183cf54e8d6059647fc3063646a1801cf30896933ec2311622cc4b9a27"
+checksum = "70d58bf43669b5795d1576d0641cfb6fbb2057bf629506267a92807158584a13"
 dependencies = [
  "lock_api",
  "parking_lot_core",
@@ -1069,9 +1075,9 @@ dependencies = [
 
 [[package]]
 name = "parking_lot_core"
-version = "0.9.10"
+version = "0.9.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1e401f977ab385c9e4e3ab30627d6f26d00e2c73eef317493c4ec6d468726cf8"
+checksum = "bc838d2a56b5b1a6c25f55575dfc605fabb63bb2365f6c2353ef9159aa69e4a5"
 dependencies = [
  "cfg-if",
  "libc",
@@ -1206,9 +1212,9 @@ dependencies = [
 
 [[package]]
 name = "portable-atomic"
-version = "1.11.0"
+version = "1.11.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "350e9b48cbc6b0e028b0473b114454c6316e57336ee184ceab6e53f72c178b3e"
+checksum = "f84267b20a16ea918e43c6a88433c2d54fa145c92a811b5b047ccbe153674483"
 
 [[package]]
 name = "portable-atomic-util"
@@ -1249,7 +1255,7 @@ version = "0.10.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "76979bea66e7875e7509c4ec5300112b316af87fa7a252ca91c448b32dfe3993"
 dependencies = [
- "bitflags 2.9.0",
+ "bitflags 2.9.1",
  "memchr",
  "pulldown-cmark-escape 0.10.1",
  "unicase",
@@ -1261,7 +1267,7 @@ version = "0.12.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f86ba2052aebccc42cbbb3ed234b8b13ce76f75c3551a303cb2bcffcff12bb14"
 dependencies = [
- "bitflags 2.9.0",
+ "bitflags 2.9.1",
  "getopts",
  "memchr",
  "pulldown-cmark-escape 0.11.0",
@@ -1315,11 +1321,11 @@ checksum = "74765f6d916ee2faa39bc8e68e4f3ed8949b48cccdac59983d287a7cb71ce9c5"
 
 [[package]]
 name = "railroad"
-version = "0.3.2"
+version = "0.3.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0ecedffc46c1b2cb04f4b80e094eae6b3f3f470a9635f1f396dd5206428f6b58"
+checksum = "e6d5b8e8a7c20c600f9b98cbf46b64e63d5c9e69deb98cee1ff264de9f1dda5d"
 dependencies = [
- "unicode-width",
+ "unicode-width 0.2.0",
 ]
 
 [[package]]
@@ -1343,7 +1349,7 @@ version = "0.5.12"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "928fca9cf2aa042393a8325b9ead81d2f0df4cb12e1e24cef072922ccd99c5af"
 dependencies = [
- "bitflags 2.9.0",
+ "bitflags 2.9.1",
 ]
 
 [[package]]
@@ -1393,7 +1399,7 @@ version = "1.0.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c71e83d6afe7ff64890ec6b71d6a69bb8a610ab78ce364b3352876bb4c801266"
 dependencies = [
- "bitflags 2.9.0",
+ "bitflags 2.9.1",
  "errno",
  "libc",
  "linux-raw-sys",
@@ -1402,9 +1408,9 @@ dependencies = [
 
 [[package]]
 name = "rustversion"
-version = "1.0.20"
+version = "1.0.21"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "eded382c5f5f786b989652c49544c4877d9f015cc22e145a5ea8ea66c2921cd2"
+checksum = "8a0d197bd2c9dc6e53b84da9556a69ba4cdfab8619eb41a8bd1cc2027a0f6b1d"
 
 [[package]]
 name = "ryu"
@@ -1467,9 +1473,9 @@ dependencies = [
 
 [[package]]
 name = "serde_spanned"
-version = "0.6.8"
+version = "0.6.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "87607cb1398ed59d48732e575a4c28a7a8ebf2454b964fe3f224f2afc07909e1"
+checksum = "bf41e0cfaf7226dca15e8197172c295a782857fcb97fad1808a166870dee75a3"
 dependencies = [
  "serde",
 ]
@@ -1499,9 +1505,9 @@ checksum = "56199f7ddabf13fe5074ce809e7d3f42b42ae711800501b5b16ea82ad029c39d"
 
 [[package]]
 name = "smallvec"
-version = "1.15.0"
+version = "1.15.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8917285742e9f3e1683f0a9c4e6b57960b7314d0b08d30d1ecd426713ee2eee9"
+checksum = "67b1b7a3b5fe4f1376887184045fcf45c69e92af734b7aaddc05fb777b6fbd03"
 
 [[package]]
 name = "stable_deref_trait"
@@ -1584,9 +1590,9 @@ dependencies = [
 
 [[package]]
 name = "tempfile"
-version = "3.19.1"
+version = "3.20.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7437ac7763b9b123ccf33c338a5cc1bac6f69b45a136c19bdd8a65e3916435bf"
+checksum = "e8a64e3985349f2441a1a9ef0b853f869006c3855f2cda6862a94d26ebb9d6a1"
 dependencies = [
  "fastrand",
  "getrandom",
@@ -1683,9 +1689,9 @@ dependencies = [
 
 [[package]]
 name = "toml"
-version = "0.8.22"
+version = "0.8.23"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "05ae329d1f08c4d17a59bed7ff5b5a769d062e64a62d34a3261b219e62cd5aae"
+checksum = "dc1beb996b9d83529a9e75c17a1686767d148d70663143c7854d8b4a09ced362"
 dependencies = [
  "serde",
  "serde_spanned",
@@ -1695,18 +1701,18 @@ dependencies = [
 
 [[package]]
 name = "toml_datetime"
-version = "0.6.9"
+version = "0.6.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3da5db5a963e24bc68be8b17b6fa82814bb22ee8660f192bb182771d498f09a3"
+checksum = "22cddaf88f4fbc13c51aebbf5f8eceb5c7c5a9da2ac40a13519eb5b0a0e8f11c"
 dependencies = [
  "serde",
 ]
 
 [[package]]
 name = "toml_edit"
-version = "0.22.26"
+version = "0.22.27"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "310068873db2c5b3e7659d2cc35d21855dbafa50d1ce336397c666e3cb08137e"
+checksum = "41fe8c660ae4257887cf66394862d21dbca4a6ddd26f04a3560410406a2f819a"
 dependencies = [
  "indexmap",
  "serde",
@@ -1718,9 +1724,9 @@ dependencies = [
 
 [[package]]
 name = "toml_write"
-version = "0.1.1"
+version = "0.1.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "bfb942dfe1d8e29a7ee7fcbde5bd2b9a25fb89aa70caea2eba3bee836ff41076"
+checksum = "5d99f8c9a7727884afe522e9bd5edbfc91a3312b36a77b5fb8926e4c31a41801"
 
 [[package]]
 name = "topological-sort"
@@ -1759,6 +1765,12 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7dd6e30e90baa6f72411720665d41d89b9a3d039dc45b8faea1ddd07f617f6af"
 
 [[package]]
+name = "unicode-width"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1fc81956842c57dac11422a97c3b8195a1ff727f06e85c84ed2e8aa277c9a0fd"
+
+[[package]]
 name = "url"
 version = "2.5.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -1872,9 +1884,9 @@ dependencies = [
 
 [[package]]
 name = "web_atoms"
-version = "0.1.2"
+version = "0.1.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0b9c5f0bc545ea3b20b423e33b9b457764de0b3730cd957f6c6aa6c301785f6e"
+checksum = "57ffde1dc01240bdf9992e3205668b235e59421fd085e8a317ed98da0178d414"
 dependencies = [
  "phf",
  "phf_codegen",
@@ -1893,9 +1905,9 @@ dependencies = [
 
 [[package]]
 name = "windows-core"
-version = "0.61.0"
+version = "0.61.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4763c1de310c86d75a878046489e2e5ba02c649d185f21c67d4cf8a56d098980"
+checksum = "c0fdd3ddb90610c7638aa2b3a3ab2904fb9e5cdbecc643ddb3647212781c4ae3"
 dependencies = [
  "windows-implement",
  "windows-interface",
@@ -1934,18 +1946,18 @@ checksum = "76840935b766e1b0a05c0066835fb9ec80071d4c09a16f6bd5f7e655e3c14c38"
 
 [[package]]
 name = "windows-result"
-version = "0.3.2"
+version = "0.3.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c64fd11a4fd95df68efcfee5f44a294fe71b8bc6a91993e2791938abcc712252"
+checksum = "56f42bd332cc6c8eac5af113fc0c1fd6a8fd2aa08a0119358686e5160d0586c6"
 dependencies = [
  "windows-link",
 ]
 
 [[package]]
 name = "windows-strings"
-version = "0.4.0"
+version = "0.4.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7a2ba9642430ee452d5a7aa78d72907ebe8cfda358e8cb7918a2050581322f97"
+checksum = "56e6c93f3a0c3b36176cb1327a4958a0353d5d166c2a35cb268ace15e91d3b57"
 dependencies = [
  "windows-link",
 ]
@@ -2038,7 +2050,7 @@ version = "0.39.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6f42320e61fe2cfd34354ecb597f86f413484a798ba44a8ca1165c58d42da6c1"
 dependencies = [
- "bitflags 2.9.0",
+ "bitflags 2.9.1",
 ]
 
 [[package]]
diff --git a/src/tools/tidy/src/deps.rs b/src/tools/tidy/src/deps.rs
index fdca7a7a40e..170dcd626a2 100644
--- a/src/tools/tidy/src/deps.rs
+++ b/src/tools/tidy/src/deps.rs
@@ -441,6 +441,7 @@ const PERMITTED_RUSTC_DEPENDENCIES: &[&str] = &[
     "windows-strings",
     "windows-sys",
     "windows-targets",
+    "windows-threading",
     "windows_aarch64_gnullvm",
     "windows_aarch64_msvc",
     "windows_i686_gnu",
diff --git a/src/tools/tidy/src/issues.txt b/src/tools/tidy/src/issues.txt
index 3e9d79224fd..045f2f0692a 100644
--- a/src/tools/tidy/src/issues.txt
+++ b/src/tools/tidy/src/issues.txt
@@ -754,7 +754,6 @@ ui/consts/issue-46553.rs
 ui/consts/issue-47789.rs
 ui/consts/issue-50439.rs
 ui/consts/issue-52023-array-size-pointer-cast.rs
-ui/consts/issue-54224.rs
 ui/consts/issue-54348.rs
 ui/consts/issue-54387.rs
 ui/consts/issue-54582.rs