Auto merge of #128783 - GuillaumeGomez:rollup-2kvpg7s, r=GuillaumeGomez

Rollup of 9 pull requests

Successful merges:

 - #128206 (Make create_dll_import_lib easier to implement)
 - #128424 (minor `effects` cleanups)
 - #128527 (More information for fully-qualified suggestion when there are multiple impls)
 - #128656 (Enable msvc for run-make/rust-lld)
 - #128683 (bootstrap: clear miri's ui test deps when rustc changes)
 - #128700 (Migrate `simd-ffi` `run-make` test to rmake)
 - #128753 (Don't arbitrarily choose one upper bound for hidden captured region error message)
 - #128757 (Migrate `pgo-gen-lto` `run-make` test to rmake)
 - #128758 (Specify a minimum supported version for VxWorks)

Failed merges:

 - #128679 (codegen: better centralize function declaration attribute computation)

r? `@ghost`
`@rustbot` modify labels: rollup

34 files changed, 566 insertions, 473 deletions

diff --git a/Cargo.lock b/Cargo.lock
index a4b4e49f82c..eea4c28ec52 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -205,11 +205,11 @@ dependencies = [
 
 [[package]]
 name = "ar_archive_writer"
-version = "0.3.0"
+version = "0.3.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f8412a2d690663356cba5a2532f3ed55d1e8090743bc6695b88403b27df67733"
+checksum = "3f2bcb7cf51decfbbfc7ef476e28b0775b13e5eb1190f8b7df145cd53d4f4374"
 dependencies = [
- "object 0.35.0",
+ "object 0.36.2",
 ]
 
 [[package]]
@@ -2456,15 +2456,6 @@ dependencies = [
 
 [[package]]
 name = "object"
-version = "0.35.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b8ec7ab813848ba4522158d5517a6093db1ded27575b070f4177b8d12b41db5e"
-dependencies = [
- "memchr",
-]
-
-[[package]]
-name = "object"
 version = "0.36.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3f203fa8daa7bb185f760ae12bd8e097f63d17041dcdcaf675ac54cdf863170e"
diff --git a/compiler/rustc_ast_lowering/src/item.rs b/compiler/rustc_ast_lowering/src/item.rs
index 1456890a0a2..7af3945d3f9 100644
--- a/compiler/rustc_ast_lowering/src/item.rs
+++ b/compiler/rustc_ast_lowering/src/item.rs
@@ -1668,7 +1668,6 @@ impl<'hir> LoweringContext<'_, 'hir> {
                             }),
                         )),
                     )),
-                    // FIXME(effects) we might not need a default.
                     default: Some(default_ct),
                     is_host_effect: true,
                     synthetic: true,
diff --git a/compiler/rustc_borrowck/src/region_infer/opaque_types.rs b/compiler/rustc_borrowck/src/region_infer/opaque_types.rs
index 8c9de5210cd..1073ea40694 100644
--- a/compiler/rustc_borrowck/src/region_infer/opaque_types.rs
+++ b/compiler/rustc_borrowck/src/region_infer/opaque_types.rs
@@ -225,21 +225,26 @@ impl<'tcx> RegionInferenceContext<'tcx> {
 
                 // Find something that we can name
                 let upper_bound = self.approx_universal_upper_bound(vid);
-                let upper_bound = &self.definitions[upper_bound];
-                match upper_bound.external_name {
-                    Some(reg) => reg,
-                    None => {
-                        // Nothing exact found, so we pick the first one that we find.
-                        let scc = self.constraint_sccs.scc(vid);
-                        for vid in self.rev_scc_graph.as_ref().unwrap().upper_bounds(scc) {
-                            match self.definitions[vid].external_name {
-                                None => {}
-                                Some(region) if region.is_static() => {}
-                                Some(region) => return region,
-                            }
-                        }
-                        region
-                    }
+                if let Some(universal_region) = self.definitions[upper_bound].external_name {
+                    return universal_region;
+                }
+
+                // Nothing exact found, so we pick a named upper bound, if there's only one.
+                // If there's >1 universal region, then we probably are dealing w/ an intersection
+                // region which cannot be mapped back to a universal.
+                // FIXME: We could probably compute the LUB if there is one.
+                let scc = self.constraint_sccs.scc(vid);
+                let upper_bounds: Vec<_> = self
+                    .rev_scc_graph
+                    .as_ref()
+                    .unwrap()
+                    .upper_bounds(scc)
+                    .filter_map(|vid| self.definitions[vid].external_name)
+                    .filter(|r| !r.is_static())
+                    .collect();
+                match &upper_bounds[..] {
+                    [universal_region] => *universal_region,
+                    _ => region,
                 }
             }
             _ => region,
diff --git a/compiler/rustc_codegen_cranelift/src/archive.rs b/compiler/rustc_codegen_cranelift/src/archive.rs
index 1935005a08c..084654af09d 100644
--- a/compiler/rustc_codegen_cranelift/src/archive.rs
+++ b/compiler/rustc_codegen_cranelift/src/archive.rs
@@ -1,4 +1,4 @@
-use std::path::{Path, PathBuf};
+use std::path::Path;
 
 use rustc_codegen_ssa::back::archive::{
     ArArchiveBuilder, ArchiveBuilder, ArchiveBuilderBuilder, DEFAULT_OBJECT_READER,
@@ -16,10 +16,9 @@ impl ArchiveBuilderBuilder for ArArchiveBuilderBuilder {
         &self,
         sess: &Session,
         _lib_name: &str,
-        _dll_imports: &[rustc_session::cstore::DllImport],
-        _tmpdir: &Path,
-        _is_direct_dependency: bool,
-    ) -> PathBuf {
+        _import_name_and_ordinal_vector: Vec<(String, Option<u16>)>,
+        _output_path: &Path,
+    ) {
         sess.dcx().fatal("raw-dylib is not yet supported by rustc_codegen_cranelift");
     }
 }
diff --git a/compiler/rustc_codegen_gcc/src/archive.rs b/compiler/rustc_codegen_gcc/src/archive.rs
index 36f5e0f8094..0cee05f1cea 100644
--- a/compiler/rustc_codegen_gcc/src/archive.rs
+++ b/compiler/rustc_codegen_gcc/src/archive.rs
@@ -1,9 +1,8 @@
-use std::path::{Path, PathBuf};
+use std::path::Path;
 
 use rustc_codegen_ssa::back::archive::{
     ArArchiveBuilder, ArchiveBuilder, ArchiveBuilderBuilder, DEFAULT_OBJECT_READER,
 };
-use rustc_session::cstore::DllImport;
 use rustc_session::Session;
 
 pub(crate) struct ArArchiveBuilderBuilder;
@@ -17,10 +16,9 @@ impl ArchiveBuilderBuilder for ArArchiveBuilderBuilder {
         &self,
         _sess: &Session,
         _lib_name: &str,
-        _dll_imports: &[DllImport],
-        _tmpdir: &Path,
-        _is_direct_dependency: bool,
-    ) -> PathBuf {
+        _import_name_and_ordinal_vector: Vec<(String, Option<u16>)>,
+        _output_path: &Path,
+    ) {
         unimplemented!("creating dll imports is not yet supported");
     }
 }
diff --git a/compiler/rustc_codegen_llvm/messages.ftl b/compiler/rustc_codegen_llvm/messages.ftl
index 1c126e79762..267da9325c3 100644
--- a/compiler/rustc_codegen_llvm/messages.ftl
+++ b/compiler/rustc_codegen_llvm/messages.ftl
@@ -1,23 +1,13 @@
 codegen_llvm_copy_bitcode = failed to copy bitcode to object file: {$err}
 
-codegen_llvm_dlltool_fail_import_library =
-    Dlltool could not create import library with {$dlltool_path} {$dlltool_args}:
-    {$stdout}
-    {$stderr}
-
 codegen_llvm_dynamic_linking_with_lto =
     cannot prefer dynamic linking when performing LTO
     .note = only 'staticlib', 'bin', and 'cdylib' outputs are supported with LTO
 
-codegen_llvm_error_calling_dlltool =
-    Error calling dlltool '{$dlltool_path}': {$error}
 
 codegen_llvm_error_creating_import_library =
     Error creating import library for {$lib_name}: {$error}
 
-codegen_llvm_error_writing_def_file =
-    Error writing .DEF file: {$error}
-
 codegen_llvm_fixed_x18_invalid_arch = the `-Zfixed-x18` flag is not supported on the `{$arch}` architecture
 
 codegen_llvm_from_llvm_diag = {$message}
diff --git a/compiler/rustc_codegen_llvm/src/back/archive.rs b/compiler/rustc_codegen_llvm/src/back/archive.rs
index 2f5a864d70e..a2ab19ac800 100644
--- a/compiler/rustc_codegen_llvm/src/back/archive.rs
+++ b/compiler/rustc_codegen_llvm/src/back/archive.rs
@@ -1,21 +1,19 @@
 //! A helper class for dealing with static archives
 
-use std::ffi::{c_char, c_void, CStr, CString, OsString};
+use std::ffi::{c_char, c_void, CStr, CString};
 use std::path::{Path, PathBuf};
-use std::{env, io, mem, ptr, str};
+use std::{io, mem, ptr, str};
 
 use rustc_codegen_ssa::back::archive::{
-    try_extract_macho_fat_archive, ArArchiveBuilder, ArchiveBuildFailure, ArchiveBuilder,
-    ArchiveBuilderBuilder, ObjectReader, UnknownArchiveKind, DEFAULT_OBJECT_READER,
+    create_mingw_dll_import_lib, try_extract_macho_fat_archive, ArArchiveBuilder,
+    ArchiveBuildFailure, ArchiveBuilder, ArchiveBuilderBuilder, ObjectReader, UnknownArchiveKind,
+    DEFAULT_OBJECT_READER,
 };
-use rustc_session::cstore::DllImport;
+use rustc_codegen_ssa::common;
 use rustc_session::Session;
 use tracing::trace;
 
-use crate::common;
-use crate::errors::{
-    DlltoolFailImportLibrary, ErrorCallingDllTool, ErrorCreatingImportLibrary, ErrorWritingDEFFile,
-};
+use crate::errors::ErrorCreatingImportLibrary;
 use crate::llvm::archive_ro::{ArchiveRO, Child};
 use crate::llvm::{self, ArchiveKind, LLVMMachineType, LLVMRustCOFFShortExport};
 
@@ -121,116 +119,21 @@ impl ArchiveBuilderBuilder for LlvmArchiveBuilderBuilder {
         &self,
         sess: &Session,
         lib_name: &str,
-        dll_imports: &[DllImport],
-        tmpdir: &Path,
-        is_direct_dependency: bool,
-    ) -> PathBuf {
-        let name_suffix = if is_direct_dependency { "_imports" } else { "_imports_indirect" };
-        let output_path = tmpdir.join(format!("{lib_name}{name_suffix}.lib"));
-
-        let target = &sess.target;
-        let mingw_gnu_toolchain = common::is_mingw_gnu_toolchain(target);
-
-        let import_name_and_ordinal_vector: Vec<(String, Option<u16>)> = dll_imports
-            .iter()
-            .map(|import: &DllImport| {
-                if sess.target.arch == "x86" {
-                    (
-                        common::i686_decorated_name(import, mingw_gnu_toolchain, false),
-                        import.ordinal(),
-                    )
-                } else {
-                    (import.name.to_string(), import.ordinal())
-                }
-            })
-            .collect();
-
-        if mingw_gnu_toolchain {
+        import_name_and_ordinal_vector: Vec<(String, Option<u16>)>,
+        output_path: &Path,
+    ) {
+        if common::is_mingw_gnu_toolchain(&sess.target) {
             // The binutils linker used on -windows-gnu targets cannot read the import
             // libraries generated by LLVM: in our attempts, the linker produced an .EXE
             // that loaded but crashed with an AV upon calling one of the imported
             // functions. Therefore, use binutils to create the import library instead,
             // by writing a .DEF file to the temp dir and calling binutils's dlltool.
-            let def_file_path = tmpdir.join(format!("{lib_name}{name_suffix}.def"));
-
-            let def_file_content = format!(
-                "EXPORTS\n{}",
-                import_name_and_ordinal_vector
-                    .into_iter()
-                    .map(|(name, ordinal)| {
-                        match ordinal {
-                            Some(n) => format!("{name} @{n} NONAME"),
-                            None => name,
-                        }
-                    })
-                    .collect::<Vec<String>>()
-                    .join("\n")
+            create_mingw_dll_import_lib(
+                sess,
+                lib_name,
+                import_name_and_ordinal_vector,
+                output_path,
             );
-
-            match std::fs::write(&def_file_path, def_file_content) {
-                Ok(_) => {}
-                Err(e) => {
-                    sess.dcx().emit_fatal(ErrorWritingDEFFile { error: e });
-                }
-            };
-
-            // --no-leading-underscore: For the `import_name_type` feature to work, we need to be
-            // able to control the *exact* spelling of each of the symbols that are being imported:
-            // hence we don't want `dlltool` adding leading underscores automatically.
-            let dlltool = find_binutils_dlltool(sess);
-            let temp_prefix = {
-                let mut path = PathBuf::from(&output_path);
-                path.pop();
-                path.push(lib_name);
-                path
-            };
-            // dlltool target architecture args from:
-            // https://github.com/llvm/llvm-project-release-prs/blob/llvmorg-15.0.6/llvm/lib/ToolDrivers/llvm-dlltool/DlltoolDriver.cpp#L69
-            let (dlltool_target_arch, dlltool_target_bitness) = match sess.target.arch.as_ref() {
-                "x86_64" => ("i386:x86-64", "--64"),
-                "x86" => ("i386", "--32"),
-                "aarch64" => ("arm64", "--64"),
-                "arm" => ("arm", "--32"),
-                _ => panic!("unsupported arch {}", sess.target.arch),
-            };
-            let mut dlltool_cmd = std::process::Command::new(&dlltool);
-            dlltool_cmd
-                .arg("-d")
-                .arg(def_file_path)
-                .arg("-D")
-                .arg(lib_name)
-                .arg("-l")
-                .arg(&output_path)
-                .arg("-m")
-                .arg(dlltool_target_arch)
-                .arg("-f")
-                .arg(dlltool_target_bitness)
-                .arg("--no-leading-underscore")
-                .arg("--temp-prefix")
-                .arg(temp_prefix);
-
-            match dlltool_cmd.output() {
-                Err(e) => {
-                    sess.dcx().emit_fatal(ErrorCallingDllTool {
-                        dlltool_path: dlltool.to_string_lossy(),
-                        error: e,
-                    });
-                }
-                // dlltool returns '0' on failure, so check for error output instead.
-                Ok(output) if !output.stderr.is_empty() => {
-                    sess.dcx().emit_fatal(DlltoolFailImportLibrary {
-                        dlltool_path: dlltool.to_string_lossy(),
-                        dlltool_args: dlltool_cmd
-                            .get_args()
-                            .map(|arg| arg.to_string_lossy())
-                            .collect::<Vec<_>>()
-                            .join(" "),
-                        stdout: String::from_utf8_lossy(&output.stdout),
-                        stderr: String::from_utf8_lossy(&output.stderr),
-                    })
-                }
-                _ => {}
-            }
         } else {
             // we've checked for \0 characters in the library name already
             let dll_name_z = CString::new(lib_name).unwrap();
@@ -242,9 +145,9 @@ impl ArchiveBuilderBuilder for LlvmArchiveBuilderBuilder {
             trace!("  output_path {}", output_path.display());
             trace!(
                 "  import names: {}",
-                dll_imports
+                import_name_and_ordinal_vector
                     .iter()
-                    .map(|import| import.name.to_string())
+                    .map(|(name, _ordinal)| name.clone())
                     .collect::<Vec<_>>()
                     .join(", "),
             );
@@ -281,9 +184,7 @@ impl ArchiveBuilderBuilder for LlvmArchiveBuilderBuilder {
                     error: llvm::last_error().unwrap_or("unknown LLVM error".to_string()),
                 });
             }
-        };
-
-        output_path
+        }
     }
 }
 
@@ -457,39 +358,3 @@ impl<'a> LlvmArchiveBuilder<'a> {
 fn string_to_io_error(s: String) -> io::Error {
     io::Error::new(io::ErrorKind::Other, format!("bad archive: {s}"))
 }
-
-fn find_binutils_dlltool(sess: &Session) -> OsString {
-    assert!(sess.target.options.is_like_windows && !sess.target.options.is_like_msvc);
-    if let Some(dlltool_path) = &sess.opts.cg.dlltool {
-        return dlltool_path.clone().into_os_string();
-    }
-
-    let tool_name: OsString = if sess.host.options.is_like_windows {
-        // If we're compiling on Windows, always use "dlltool.exe".
-        "dlltool.exe"
-    } else {
-        // On other platforms, use the architecture-specific name.
-        match sess.target.arch.as_ref() {
-            "x86_64" => "x86_64-w64-mingw32-dlltool",
-            "x86" => "i686-w64-mingw32-dlltool",
-            "aarch64" => "aarch64-w64-mingw32-dlltool",
-
-            // For non-standard architectures (e.g., aarch32) fallback to "dlltool".
-            _ => "dlltool",
-        }
-    }
-    .into();
-
-    // NOTE: it's not clear how useful it is to explicitly search PATH.
-    for dir in env::split_paths(&env::var_os("PATH").unwrap_or_default()) {
-        let full_path = dir.join(&tool_name);
-        if full_path.is_file() {
-            return full_path.into_os_string();
-        }
-    }
-
-    // The user didn't specify the location of the dlltool binary, and we weren't able
-    // to find the appropriate one on the PATH. Just return the name of the tool
-    // and let the invocation fail with a hopefully useful error message.
-    tool_name
-}
diff --git a/compiler/rustc_codegen_llvm/src/callee.rs b/compiler/rustc_codegen_llvm/src/callee.rs
index c913bdebaaa..9030b3d848f 100644
--- a/compiler/rustc_codegen_llvm/src/callee.rs
+++ b/compiler/rustc_codegen_llvm/src/callee.rs
@@ -4,13 +4,14 @@
 //! and methods are represented as just a fn ptr and not a full
 //! closure.
 
+use rustc_codegen_ssa::common;
 use rustc_middle::ty::layout::{FnAbiOf, HasTyCtxt};
 use rustc_middle::ty::{self, Instance, TypeVisitableExt};
 use tracing::debug;
 
 use crate::context::CodegenCx;
 use crate::value::Value;
-use crate::{attributes, common, llvm};
+use crate::{attributes, llvm};
 
 /// Codegens a reference to a fn/method item, monomorphizing and
 /// inlining as it goes.
@@ -46,7 +47,7 @@ pub fn get_fn<'ll, 'tcx>(cx: &CodegenCx<'ll, 'tcx>, instance: Instance<'tcx>) ->
     } else {
         let instance_def_id = instance.def_id();
         let llfn = if tcx.sess.target.arch == "x86"
-            && let Some(dllimport) = common::get_dllimport(tcx, instance_def_id, sym)
+            && let Some(dllimport) = crate::common::get_dllimport(tcx, instance_def_id, sym)
         {
             // Fix for https://github.com/rust-lang/rust/issues/104453
             // On x86 Windows, LLVM uses 'L' as the prefix for any private
diff --git a/compiler/rustc_codegen_llvm/src/common.rs b/compiler/rustc_codegen_llvm/src/common.rs
index 197bbb9ddbf..65f974c5689 100644
--- a/compiler/rustc_codegen_llvm/src/common.rs
+++ b/compiler/rustc_codegen_llvm/src/common.rs
@@ -1,7 +1,5 @@
 //! Code that is useful in various codegen modules.
 
-use std::fmt::Write;
-
 use libc::{c_char, c_uint};
 use rustc_ast::Mutability;
 use rustc_codegen_ssa::traits::*;
@@ -10,9 +8,8 @@ use rustc_hir::def_id::DefId;
 use rustc_middle::bug;
 use rustc_middle::mir::interpret::{ConstAllocation, GlobalAlloc, Scalar};
 use rustc_middle::ty::TyCtxt;
-use rustc_session::cstore::{DllCallingConvention, DllImport, PeImportNameType};
+use rustc_session::cstore::DllImport;
 use rustc_target::abi::{self, AddressSpace, HasDataLayout, Pointer};
-use rustc_target::spec::Target;
 use tracing::debug;
 
 use crate::consts::const_alloc_to_llvm;
@@ -379,64 +376,3 @@ pub(crate) fn get_dllimport<'tcx>(
     tcx.native_library(id)
         .and_then(|lib| lib.dll_imports.iter().find(|di| di.name.as_str() == name))
 }
-
-pub(crate) fn is_mingw_gnu_toolchain(target: &Target) -> bool {
-    target.vendor == "pc" && target.os == "windows" && target.env == "gnu" && target.abi.is_empty()
-}
-
-pub(crate) fn i686_decorated_name(
-    dll_import: &DllImport,
-    mingw: bool,
-    disable_name_mangling: bool,
-) -> String {
-    let name = dll_import.name.as_str();
-
-    let (add_prefix, add_suffix) = match dll_import.import_name_type {
-        Some(PeImportNameType::NoPrefix) => (false, true),
-        Some(PeImportNameType::Undecorated) => (false, false),
-        _ => (true, true),
-    };
-
-    // Worst case: +1 for disable name mangling, +1 for prefix, +4 for suffix (@@__).
-    let mut decorated_name = String::with_capacity(name.len() + 6);
-
-    if disable_name_mangling {
-        // LLVM uses a binary 1 ('\x01') prefix to a name to indicate that mangling needs to be disabled.
-        decorated_name.push('\x01');
-    }
-
-    let prefix = if add_prefix && dll_import.is_fn {
-        match dll_import.calling_convention {
-            DllCallingConvention::C | DllCallingConvention::Vectorcall(_) => None,
-            DllCallingConvention::Stdcall(_) => (!mingw
-                || dll_import.import_name_type == Some(PeImportNameType::Decorated))
-            .then_some('_'),
-            DllCallingConvention::Fastcall(_) => Some('@'),
-        }
-    } else if !dll_import.is_fn && !mingw {
-        // For static variables, prefix with '_' on MSVC.
-        Some('_')
-    } else {
-        None
-    };
-    if let Some(prefix) = prefix {
-        decorated_name.push(prefix);
-    }
-
-    decorated_name.push_str(name);
-
-    if add_suffix && dll_import.is_fn {
-        match dll_import.calling_convention {
-            DllCallingConvention::C => {}
-            DllCallingConvention::Stdcall(arg_list_size)
-            | DllCallingConvention::Fastcall(arg_list_size) => {
-                write!(&mut decorated_name, "@{arg_list_size}").unwrap();
-            }
-            DllCallingConvention::Vectorcall(arg_list_size) => {
-                write!(&mut decorated_name, "@@{arg_list_size}").unwrap();
-            }
-        }
-    }
-
-    decorated_name
-}
diff --git a/compiler/rustc_codegen_llvm/src/consts.rs b/compiler/rustc_codegen_llvm/src/consts.rs
index c3ea4a18a71..75b298f14ca 100644
--- a/compiler/rustc_codegen_llvm/src/consts.rs
+++ b/compiler/rustc_codegen_llvm/src/consts.rs
@@ -1,5 +1,6 @@
 use std::ops::Range;
 
+use rustc_codegen_ssa::common;
 use rustc_codegen_ssa::traits::*;
 use rustc_hir::def::DefKind;
 use rustc_hir::def_id::DefId;
@@ -18,7 +19,7 @@ use rustc_target::abi::{
 };
 use tracing::{debug, instrument, trace};
 
-use crate::common::{self, CodegenCx};
+use crate::common::CodegenCx;
 use crate::errors::{
     InvalidMinimumAlignmentNotPowerOfTwo, InvalidMinimumAlignmentTooLarge, SymbolAlreadyDefined,
 };
@@ -195,7 +196,7 @@ fn check_and_apply_linkage<'ll, 'tcx>(
             g2
         }
     } else if cx.tcx.sess.target.arch == "x86"
-        && let Some(dllimport) = common::get_dllimport(cx.tcx, def_id, sym)
+        && let Some(dllimport) = crate::common::get_dllimport(cx.tcx, def_id, sym)
     {
         cx.declare_global(
             &common::i686_decorated_name(
diff --git a/compiler/rustc_codegen_llvm/src/errors.rs b/compiler/rustc_codegen_llvm/src/errors.rs
index a3957bc52a5..7e53d32ce8c 100644
--- a/compiler/rustc_codegen_llvm/src/errors.rs
+++ b/compiler/rustc_codegen_llvm/src/errors.rs
@@ -1,4 +1,3 @@
-use std::borrow::Cow;
 use std::ffi::CString;
 use std::path::Path;
 
@@ -72,28 +71,6 @@ pub(crate) struct InvalidMinimumAlignmentTooLarge {
 pub(crate) struct SanitizerMemtagRequiresMte;
 
 #[derive(Diagnostic)]
-#[diag(codegen_llvm_error_writing_def_file)]
-pub(crate) struct ErrorWritingDEFFile {
-    pub error: std::io::Error,
-}
-
-#[derive(Diagnostic)]
-#[diag(codegen_llvm_error_calling_dlltool)]
-pub(crate) struct ErrorCallingDllTool<'a> {
-    pub dlltool_path: Cow<'a, str>,
-    pub error: std::io::Error,
-}
-
-#[derive(Diagnostic)]
-#[diag(codegen_llvm_dlltool_fail_import_library)]
-pub(crate) struct DlltoolFailImportLibrary<'a> {
-    pub dlltool_path: Cow<'a, str>,
-    pub dlltool_args: String,
-    pub stdout: Cow<'a, str>,
-    pub stderr: Cow<'a, str>,
-}
-
-#[derive(Diagnostic)]
 #[diag(codegen_llvm_dynamic_linking_with_lto)]
 #[note]
 pub(crate) struct DynamicLinkingWithLTO;
diff --git a/compiler/rustc_codegen_ssa/Cargo.toml b/compiler/rustc_codegen_ssa/Cargo.toml
index 2767ad5ec9c..6e1c323cbd0 100644
--- a/compiler/rustc_codegen_ssa/Cargo.toml
+++ b/compiler/rustc_codegen_ssa/Cargo.toml
@@ -5,7 +5,7 @@ edition = "2021"
 
 [dependencies]
 # tidy-alphabetical-start
-ar_archive_writer = "0.3.0"
+ar_archive_writer = "0.3.3"
 arrayvec = { version = "0.7", default-features = false }
 bitflags = "2.4.1"
 cc = "1.0.90"
diff --git a/compiler/rustc_codegen_ssa/messages.ftl b/compiler/rustc_codegen_ssa/messages.ftl
index 57d789aef80..80f25d42a08 100644
--- a/compiler/rustc_codegen_ssa/messages.ftl
+++ b/compiler/rustc_codegen_ssa/messages.ftl
@@ -24,8 +24,19 @@ codegen_ssa_copy_path_buf = unable to copy {$source_file} to {$output_path}: {$e
 
 codegen_ssa_create_temp_dir = couldn't create a temp dir: {$error}
 
+codegen_ssa_dlltool_fail_import_library =
+    Dlltool could not create import library with {$dlltool_path} {$dlltool_args}:
+    {$stdout}
+    {$stderr}
+
+codegen_ssa_error_calling_dlltool =
+    Error calling dlltool '{$dlltool_path}': {$error}
+
 codegen_ssa_error_creating_remark_dir = failed to create remark directory: {$error}
 
+codegen_ssa_error_writing_def_file =
+    Error writing .DEF file: {$error}
+
 codegen_ssa_expected_used_symbol = expected `used`, `used(compiler)` or `used(linker)`
 
 codegen_ssa_extern_funcs_not_found = some `extern` functions couldn't be found; some native libraries may need to be installed or have their path specified
diff --git a/compiler/rustc_codegen_ssa/src/back/archive.rs b/compiler/rustc_codegen_ssa/src/back/archive.rs
index 4f93b7b23c6..ce55d99f506 100644
--- a/compiler/rustc_codegen_ssa/src/back/archive.rs
+++ b/compiler/rustc_codegen_ssa/src/back/archive.rs
@@ -1,4 +1,6 @@
+use std::env;
 use std::error::Error;
+use std::ffi::OsString;
 use std::fs::{self, File};
 use std::io::{self, Write};
 use std::path::{Path, PathBuf};
@@ -9,7 +11,6 @@ use object::read::archive::ArchiveFile;
 use object::read::macho::FatArch;
 use rustc_data_structures::fx::FxIndexSet;
 use rustc_data_structures::memmap::Mmap;
-use rustc_session::cstore::DllImport;
 use rustc_session::Session;
 use rustc_span::symbol::Symbol;
 use tempfile::Builder as TempFileBuilder;
@@ -17,6 +18,7 @@ use tempfile::Builder as TempFileBuilder;
 use super::metadata::search_for_section;
 // Re-exporting for rustc_codegen_llvm::back::archive
 pub use crate::errors::{ArchiveBuildFailure, ExtractBundledLibsError, UnknownArchiveKind};
+use crate::errors::{DlltoolFailImportLibrary, ErrorCallingDllTool, ErrorWritingDEFFile};
 
 pub trait ArchiveBuilderBuilder {
     fn new_archive_builder<'a>(&self, sess: &'a Session) -> Box<dyn ArchiveBuilder + 'a>;
@@ -30,10 +32,9 @@ pub trait ArchiveBuilderBuilder {
         &self,
         sess: &Session,
         lib_name: &str,
-        dll_imports: &[DllImport],
-        tmpdir: &Path,
-        is_direct_dependency: bool,
-    ) -> PathBuf;
+        import_name_and_ordinal_vector: Vec<(String, Option<u16>)>,
+        output_path: &Path,
+    );
 
     fn extract_bundled_libs<'a>(
         &'a self,
@@ -72,6 +73,130 @@ pub trait ArchiveBuilderBuilder {
     }
 }
 
+pub fn create_mingw_dll_import_lib(
+    sess: &Session,
+    lib_name: &str,
+    import_name_and_ordinal_vector: Vec<(String, Option<u16>)>,
+    output_path: &Path,
+) {
+    let def_file_path = output_path.with_extension("def");
+
+    let def_file_content = format!(
+        "EXPORTS\n{}",
+        import_name_and_ordinal_vector
+            .into_iter()
+            .map(|(name, ordinal)| {
+                match ordinal {
+                    Some(n) => format!("{name} @{n} NONAME"),
+                    None => name,
+                }
+            })
+            .collect::<Vec<String>>()
+            .join("\n")
+    );
+
+    match std::fs::write(&def_file_path, def_file_content) {
+        Ok(_) => {}
+        Err(e) => {
+            sess.dcx().emit_fatal(ErrorWritingDEFFile { error: e });
+        }
+    };
+
+    // --no-leading-underscore: For the `import_name_type` feature to work, we need to be
+    // able to control the *exact* spelling of each of the symbols that are being imported:
+    // hence we don't want `dlltool` adding leading underscores automatically.
+    let dlltool = find_binutils_dlltool(sess);
+    let temp_prefix = {
+        let mut path = PathBuf::from(&output_path);
+        path.pop();
+        path.push(lib_name);
+        path
+    };
+    // dlltool target architecture args from:
+    // https://github.com/llvm/llvm-project-release-prs/blob/llvmorg-15.0.6/llvm/lib/ToolDrivers/llvm-dlltool/DlltoolDriver.cpp#L69
+    let (dlltool_target_arch, dlltool_target_bitness) = match sess.target.arch.as_ref() {
+        "x86_64" => ("i386:x86-64", "--64"),
+        "x86" => ("i386", "--32"),
+        "aarch64" => ("arm64", "--64"),
+        "arm" => ("arm", "--32"),
+        _ => panic!("unsupported arch {}", sess.target.arch),
+    };
+    let mut dlltool_cmd = std::process::Command::new(&dlltool);
+    dlltool_cmd
+        .arg("-d")
+        .arg(def_file_path)
+        .arg("-D")
+        .arg(lib_name)
+        .arg("-l")
+        .arg(&output_path)
+        .arg("-m")
+        .arg(dlltool_target_arch)
+        .arg("-f")
+        .arg(dlltool_target_bitness)
+        .arg("--no-leading-underscore")
+        .arg("--temp-prefix")
+        .arg(temp_prefix);
+
+    match dlltool_cmd.output() {
+        Err(e) => {
+            sess.dcx().emit_fatal(ErrorCallingDllTool {
+                dlltool_path: dlltool.to_string_lossy(),
+                error: e,
+            });
+        }
+        // dlltool returns '0' on failure, so check for error output instead.
+        Ok(output) if !output.stderr.is_empty() => {
+            sess.dcx().emit_fatal(DlltoolFailImportLibrary {
+                dlltool_path: dlltool.to_string_lossy(),
+                dlltool_args: dlltool_cmd
+                    .get_args()
+                    .map(|arg| arg.to_string_lossy())
+                    .collect::<Vec<_>>()
+                    .join(" "),
+                stdout: String::from_utf8_lossy(&output.stdout),
+                stderr: String::from_utf8_lossy(&output.stderr),
+            })
+        }
+        _ => {}
+    }
+}
+
+fn find_binutils_dlltool(sess: &Session) -> OsString {
+    assert!(sess.target.options.is_like_windows && !sess.target.options.is_like_msvc);
+    if let Some(dlltool_path) = &sess.opts.cg.dlltool {
+        return dlltool_path.clone().into_os_string();
+    }
+
+    let tool_name: OsString = if sess.host.options.is_like_windows {
+        // If we're compiling on Windows, always use "dlltool.exe".
+        "dlltool.exe"
+    } else {
+        // On other platforms, use the architecture-specific name.
+        match sess.target.arch.as_ref() {
+            "x86_64" => "x86_64-w64-mingw32-dlltool",
+            "x86" => "i686-w64-mingw32-dlltool",
+            "aarch64" => "aarch64-w64-mingw32-dlltool",
+
+            // For non-standard architectures (e.g., aarch32) fallback to "dlltool".
+            _ => "dlltool",
+        }
+    }
+    .into();
+
+    // NOTE: it's not clear how useful it is to explicitly search PATH.
+    for dir in env::split_paths(&env::var_os("PATH").unwrap_or_default()) {
+        let full_path = dir.join(&tool_name);
+        if full_path.is_file() {
+            return full_path.into_os_string();
+        }
+    }
+
+    // The user didn't specify the location of the dlltool binary, and we weren't able
+    // to find the appropriate one on the PATH. Just return the name of the tool
+    // and let the invocation fail with a hopefully useful error message.
+    tool_name
+}
+
 pub trait ArchiveBuilder {
     fn add_file(&mut self, path: &Path);
 
diff --git a/compiler/rustc_codegen_ssa/src/back/link.rs b/compiler/rustc_codegen_ssa/src/back/link.rs
index 653895380be..45a92fd03d5 100644
--- a/compiler/rustc_codegen_ssa/src/back/link.rs
+++ b/compiler/rustc_codegen_ssa/src/back/link.rs
@@ -51,7 +51,8 @@ use super::linker::{self, Linker};
 use super::metadata::{create_wrapper_file, MetadataPosition};
 use super::rpath::{self, RPathConfig};
 use crate::{
-    errors, looks_like_rust_object_file, CodegenResults, CompiledModule, CrateInfo, NativeLib,
+    common, errors, looks_like_rust_object_file, CodegenResults, CompiledModule, CrateInfo,
+    NativeLib,
 };
 
 pub fn ensure_removed(dcx: DiagCtxtHandle<'_>, path: &Path) {
@@ -390,17 +391,13 @@ fn link_rlib<'a>(
         }
     }
 
-    for (raw_dylib_name, raw_dylib_imports) in
-        collate_raw_dylibs(sess, codegen_results.crate_info.used_libraries.iter())?
-    {
-        let output_path = archive_builder_builder.create_dll_import_lib(
-            sess,
-            &raw_dylib_name,
-            &raw_dylib_imports,
-            tmpdir.as_ref(),
-            true,
-        );
-
+    for output_path in create_dll_import_libs(
+        sess,
+        archive_builder_builder,
+        codegen_results.crate_info.used_libraries.iter(),
+        tmpdir.as_ref(),
+        true,
+    )? {
         ab.add_archive(&output_path, Box::new(|_| false)).unwrap_or_else(|error| {
             sess.dcx().emit_fatal(errors::AddNativeLibrary { library_path: output_path, error });
         });
@@ -488,6 +485,47 @@ fn collate_raw_dylibs<'a>(
         .collect())
 }
 
+fn create_dll_import_libs<'a>(
+    sess: &Session,
+    archive_builder_builder: &dyn ArchiveBuilderBuilder,
+    used_libraries: impl IntoIterator<Item = &'a NativeLib>,
+    tmpdir: &Path,
+    is_direct_dependency: bool,
+) -> Result<Vec<PathBuf>, ErrorGuaranteed> {
+    Ok(collate_raw_dylibs(sess, used_libraries)?
+        .into_iter()
+        .map(|(raw_dylib_name, raw_dylib_imports)| {
+            let name_suffix = if is_direct_dependency { "_imports" } else { "_imports_indirect" };
+            let output_path = tmpdir.join(format!("{raw_dylib_name}{name_suffix}.lib"));
+
+            let mingw_gnu_toolchain = common::is_mingw_gnu_toolchain(&sess.target);
+
+            let import_name_and_ordinal_vector: Vec<(String, Option<u16>)> = raw_dylib_imports
+                .iter()
+                .map(|import: &DllImport| {
+                    if sess.target.arch == "x86" {
+                        (
+                            common::i686_decorated_name(import, mingw_gnu_toolchain, false),
+                            import.ordinal(),
+                        )
+                    } else {
+                        (import.name.to_string(), import.ordinal())
+                    }
+                })
+                .collect();
+
+            archive_builder_builder.create_dll_import_lib(
+                sess,
+                &raw_dylib_name,
+                import_name_and_ordinal_vector,
+                &output_path,
+            );
+
+            output_path
+        })
+        .collect())
+}
+
 /// Create a static archive.
 ///
 /// This is essentially the same thing as an rlib, but it also involves adding all of the upstream
@@ -2305,16 +2343,14 @@ fn linker_with_args(
     );
 
     // Link with the import library generated for any raw-dylib functions.
-    for (raw_dylib_name, raw_dylib_imports) in
-        collate_raw_dylibs(sess, codegen_results.crate_info.used_libraries.iter())?
-    {
-        cmd.add_object(&archive_builder_builder.create_dll_import_lib(
-            sess,
-            &raw_dylib_name,
-            &raw_dylib_imports,
-            tmpdir,
-            true,
-        ));
+    for output_path in create_dll_import_libs(
+        sess,
+        archive_builder_builder,
+        codegen_results.crate_info.used_libraries.iter(),
+        tmpdir,
+        true,
+    )? {
+        cmd.add_object(&output_path);
     }
     // As with add_upstream_native_libraries, we need to add the upstream raw-dylib symbols in case
     // they are used within inlined functions or instantiated generic functions. We do this *after*
@@ -2339,16 +2375,14 @@ fn linker_with_args(
         .flatten()
         .collect::<Vec<_>>();
     native_libraries_from_nonstatics.sort_unstable_by(|a, b| a.name.as_str().cmp(b.name.as_str()));
-    for (raw_dylib_name, raw_dylib_imports) in
-        collate_raw_dylibs(sess, native_libraries_from_nonstatics)?
-    {
-        cmd.add_object(&archive_builder_builder.create_dll_import_lib(
-            sess,
-            &raw_dylib_name,
-            &raw_dylib_imports,
-            tmpdir,
-            false,
-        ));
+    for output_path in create_dll_import_libs(
+        sess,
+        archive_builder_builder,
+        native_libraries_from_nonstatics,
+        tmpdir,
+        false,
+    )? {
+        cmd.add_object(&output_path);
     }
 
     // Library linking above uses some global state for things like `-Bstatic`/`-Bdynamic` to make
diff --git a/compiler/rustc_codegen_ssa/src/common.rs b/compiler/rustc_codegen_ssa/src/common.rs
index a972c0cd99d..bfb1d217eae 100644
--- a/compiler/rustc_codegen_ssa/src/common.rs
+++ b/compiler/rustc_codegen_ssa/src/common.rs
@@ -4,7 +4,9 @@ use rustc_hir::LangItem;
 use rustc_middle::ty::layout::TyAndLayout;
 use rustc_middle::ty::{self, Instance, TyCtxt};
 use rustc_middle::{bug, mir, span_bug};
+use rustc_session::cstore::{DllCallingConvention, DllImport, PeImportNameType};
 use rustc_span::Span;
+use rustc_target::spec::Target;
 
 use crate::traits::*;
 
@@ -176,3 +178,66 @@ pub fn asm_const_to_str<'tcx>(
         _ => span_bug!(sp, "asm const has bad type {}", ty_and_layout.ty),
     }
 }
+
+pub fn is_mingw_gnu_toolchain(target: &Target) -> bool {
+    target.vendor == "pc" && target.os == "windows" && target.env == "gnu" && target.abi.is_empty()
+}
+
+pub fn i686_decorated_name(
+    dll_import: &DllImport,
+    mingw: bool,
+    disable_name_mangling: bool,
+) -> String {
+    let name = dll_import.name.as_str();
+
+    let (add_prefix, add_suffix) = match dll_import.import_name_type {
+        Some(PeImportNameType::NoPrefix) => (false, true),
+        Some(PeImportNameType::Undecorated) => (false, false),
+        _ => (true, true),
+    };
+
+    // Worst case: +1 for disable name mangling, +1 for prefix, +4 for suffix (@@__).
+    let mut decorated_name = String::with_capacity(name.len() + 6);
+
+    if disable_name_mangling {
+        // LLVM uses a binary 1 ('\x01') prefix to a name to indicate that mangling needs to be disabled.
+        decorated_name.push('\x01');
+    }
+
+    let prefix = if add_prefix && dll_import.is_fn {
+        match dll_import.calling_convention {
+            DllCallingConvention::C | DllCallingConvention::Vectorcall(_) => None,
+            DllCallingConvention::Stdcall(_) => (!mingw
+                || dll_import.import_name_type == Some(PeImportNameType::Decorated))
+            .then_some('_'),
+            DllCallingConvention::Fastcall(_) => Some('@'),
+        }
+    } else if !dll_import.is_fn && !mingw {
+        // For static variables, prefix with '_' on MSVC.
+        Some('_')
+    } else {
+        None
+    };
+    if let Some(prefix) = prefix {
+        decorated_name.push(prefix);
+    }
+
+    decorated_name.push_str(name);
+
+    if add_suffix && dll_import.is_fn {
+        use std::fmt::Write;
+
+        match dll_import.calling_convention {
+            DllCallingConvention::C => {}
+            DllCallingConvention::Stdcall(arg_list_size)
+            | DllCallingConvention::Fastcall(arg_list_size) => {
+                write!(&mut decorated_name, "@{arg_list_size}").unwrap();
+            }
+            DllCallingConvention::Vectorcall(arg_list_size) => {
+                write!(&mut decorated_name, "@@{arg_list_size}").unwrap();
+            }
+        }
+    }
+
+    decorated_name
+}
diff --git a/compiler/rustc_codegen_ssa/src/errors.rs b/compiler/rustc_codegen_ssa/src/errors.rs
index 2d1eae630cf..94bf0ab34e2 100644
--- a/compiler/rustc_codegen_ssa/src/errors.rs
+++ b/compiler/rustc_codegen_ssa/src/errors.rs
@@ -1027,6 +1027,28 @@ pub struct FailedToGetLayout<'tcx> {
 }
 
 #[derive(Diagnostic)]
+#[diag(codegen_ssa_dlltool_fail_import_library)]
+pub(crate) struct DlltoolFailImportLibrary<'a> {
+    pub dlltool_path: Cow<'a, str>,
+    pub dlltool_args: String,
+    pub stdout: Cow<'a, str>,
+    pub stderr: Cow<'a, str>,
+}
+
+#[derive(Diagnostic)]
+#[diag(codegen_ssa_error_writing_def_file)]
+pub(crate) struct ErrorWritingDEFFile {
+    pub error: std::io::Error,
+}
+
+#[derive(Diagnostic)]
+#[diag(codegen_ssa_error_calling_dlltool)]
+pub(crate) struct ErrorCallingDllTool<'a> {
+    pub dlltool_path: Cow<'a, str>,
+    pub error: std::io::Error,
+}
+
+#[derive(Diagnostic)]
 #[diag(codegen_ssa_error_creating_remark_dir)]
 pub struct ErrorCreatingRemarkDir {
     pub error: std::io::Error,
diff --git a/compiler/rustc_hir_analysis/src/hir_ty_lowering/generics.rs b/compiler/rustc_hir_analysis/src/hir_ty_lowering/generics.rs
index 034a4918b50..a59e9aa85fd 100644
--- a/compiler/rustc_hir_analysis/src/hir_ty_lowering/generics.rs
+++ b/compiler/rustc_hir_analysis/src/hir_ty_lowering/generics.rs
@@ -253,32 +253,6 @@ pub fn lower_generic_args<'tcx: 'a, 'a>(
             match (args_iter.peek(), params.peek()) {
                 (Some(&arg), Some(&param)) => {
                     match (arg, &param.kind, arg_count.explicit_late_bound) {
-                        (
-                            GenericArg::Const(hir::ConstArg {
-                                is_desugared_from_effects: true,
-                                ..
-                            }),
-                            GenericParamDefKind::Const { is_host_effect: false, .. }
-                            | GenericParamDefKind::Type { .. }
-                            | GenericParamDefKind::Lifetime,
-                            _,
-                        ) => {
-                            // FIXME(effects): this should be removed
-                            // SPECIAL CASE FOR DESUGARED EFFECT PARAMS
-                            // This comes from the following example:
-                            //
-                            // ```
-                            // #[const_trait]
-                            // pub trait PartialEq<Rhs: ?Sized = Self> {}
-                            // impl const PartialEq for () {}
-                            // ```
-                            //
-                            // Since this is a const impl, we need to insert a host arg at the end of
-                            // `PartialEq`'s generics, but this errors since `Rhs` isn't specified.
-                            // To work around this, we infer all arguments until we reach the host param.
-                            args.push(ctx.inferred_kind(&args, param, infer_args));
-                            params.next();
-                        }
                         (GenericArg::Lifetime(_), GenericParamDefKind::Lifetime, _)
                         | (
                             GenericArg::Type(_) | GenericArg::Infer(_),
diff --git a/compiler/rustc_trait_selection/src/error_reporting/traits/ambiguity.rs b/compiler/rustc_trait_selection/src/error_reporting/traits/ambiguity.rs
index 72a4d4c1205..9ab47057859 100644
--- a/compiler/rustc_trait_selection/src/error_reporting/traits/ambiguity.rs
+++ b/compiler/rustc_trait_selection/src/error_reporting/traits/ambiguity.rs
@@ -388,39 +388,67 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> {
                                 trait_impls.non_blanket_impls().values().flatten().count();
                             // If there is only one implementation of the trait, suggest using it.
                             // Otherwise, use a placeholder comment for the implementation.
-                            let (message, self_type) = if non_blanket_impl_count == 1 {
+                            let (message, self_types) = if non_blanket_impl_count == 1 {
                                 (
                                     "use the fully-qualified path to the only available \
                                      implementation",
-                                    format!(
+                                    vec![format!(
                                         "{}",
                                         self.tcx.type_of(impl_def_id).instantiate_identity()
-                                    ),
+                                    )],
+                                )
+                            } else if non_blanket_impl_count < 20 {
+                                (
+                                    "use a fully-qualified path to one of the available \
+                                     implementations",
+                                    trait_impls
+                                        .non_blanket_impls()
+                                        .values()
+                                        .flatten()
+                                        .map(|id| {
+                                            format!(
+                                                "{}",
+                                                self.tcx.type_of(id).instantiate_identity()
+                                            )
+                                        })
+                                        .collect::<Vec<String>>(),
                                 )
                             } else {
                                 (
                                     "use a fully-qualified path to a specific available \
                                      implementation",
-                                    "/* self type */".to_string(),
+                                    vec!["/* self type */".to_string()],
                                 )
                             };
-                            let mut suggestions =
-                                vec![(path.span.shrink_to_lo(), format!("<{self_type} as "))];
-                            if let Some(generic_arg) = trait_path_segment.args {
-                                let between_span =
-                                    trait_path_segment.ident.span.between(generic_arg.span_ext);
-                                // get rid of :: between Trait and <type>
-                                // must be '::' between them, otherwise the parser won't accept the code
-                                suggestions.push((between_span, "".to_string()));
-                                suggestions
-                                    .push((generic_arg.span_ext.shrink_to_hi(), ">".to_string()));
-                            } else {
-                                suggestions.push((
-                                    trait_path_segment.ident.span.shrink_to_hi(),
-                                    ">".to_string(),
-                                ));
-                            }
-                            err.multipart_suggestion(
+                            let suggestions: Vec<_> = self_types
+                                .into_iter()
+                                .map(|self_type| {
+                                    let mut suggestions = vec![(
+                                        path.span.shrink_to_lo(),
+                                        format!("<{self_type} as "),
+                                    )];
+                                    if let Some(generic_arg) = trait_path_segment.args {
+                                        let between_span = trait_path_segment
+                                            .ident
+                                            .span
+                                            .between(generic_arg.span_ext);
+                                        // get rid of :: between Trait and <type>
+                                        // must be '::' between them, otherwise the parser won't accept the code
+                                        suggestions.push((between_span, "".to_string()));
+                                        suggestions.push((
+                                            generic_arg.span_ext.shrink_to_hi(),
+                                            ">".to_string(),
+                                        ));
+                                    } else {
+                                        suggestions.push((
+                                            trait_path_segment.ident.span.shrink_to_hi(),
+                                            ">".to_string(),
+                                        ));
+                                    }
+                                    suggestions
+                                })
+                                .collect();
+                            err.multipart_suggestions(
                                 message,
                                 suggestions,
                                 Applicability::MaybeIncorrect,
diff --git a/src/bootstrap/src/core/build_steps/test.rs b/src/bootstrap/src/core/build_steps/test.rs
index c40aa718e7c..597d7733abe 100644
--- a/src/bootstrap/src/core/build_steps/test.rs
+++ b/src/bootstrap/src/core/build_steps/test.rs
@@ -520,6 +520,14 @@ impl Step for Miri {
         builder.ensure(compile::Std::new(target_compiler, host));
         let host_sysroot = builder.sysroot(target_compiler);
 
+        // Miri has its own "target dir" for ui test dependencies. Make sure it gets cleared
+        // properly when rustc changes. Similar to `Builder::cargo`, we skip this in dry runs to
+        // make sure the relevant compiler has been set up properly.
+        if !builder.config.dry_run() {
+            let ui_test_dep_dir = builder.stage_out(host_compiler, Mode::ToolStd).join("miri_ui");
+            builder.clear_if_dirty(&ui_test_dep_dir, &builder.rustc(host_compiler));
+        }
+
         // Run `cargo test`.
         // This is with the Miri crate, so it uses the host compiler.
         let mut cargo = tool::prepare_tool_cargo(
diff --git a/src/doc/rustc/src/platform-support/vxworks.md b/src/doc/rustc/src/platform-support/vxworks.md
index c0a818558e0..7c73ee8cfa8 100644
--- a/src/doc/rustc/src/platform-support/vxworks.md
+++ b/src/doc/rustc/src/platform-support/vxworks.md
@@ -20,6 +20,12 @@ Target triplets available:
 
 ## Requirements
 
+### OS version
+
+The minimum supported version is VxWorks 7.
+
+## Building
+
 Rust for each target can be cross-compiled with its specific target vsb configuration. Std support is added but not yet fully tested.
 
 ## Building the target
diff --git a/src/tools/tidy/src/allowed_run_make_makefiles.txt b/src/tools/tidy/src/allowed_run_make_makefiles.txt
index ce8a4030130..5c1d9a2d47e 100644
--- a/src/tools/tidy/src/allowed_run_make_makefiles.txt
+++ b/src/tools/tidy/src/allowed_run_make_makefiles.txt
@@ -17,12 +17,10 @@ run-make/min-global-align/Makefile
 run-make/native-link-modifier-bundle/Makefile
 run-make/no-alloc-shim/Makefile
 run-make/pdb-buildinfo-cl-cmd/Makefile
-run-make/pgo-gen-lto/Makefile
 run-make/pgo-indirect-call-promotion/Makefile
 run-make/remap-path-prefix-dwarf/Makefile
 run-make/reproducible-build/Makefile
 run-make/rlib-format-packed-bundled-libs/Makefile
-run-make/simd-ffi/Makefile
 run-make/split-debuginfo/Makefile
 run-make/staticlib-dylib-linkage/Makefile
 run-make/symbol-mangling-hashed/Makefile
diff --git a/tests/run-make/pgo-gen-lto/Makefile b/tests/run-make/pgo-gen-lto/Makefile
deleted file mode 100644
index 54164c99522..00000000000
--- a/tests/run-make/pgo-gen-lto/Makefile
+++ /dev/null
@@ -1,11 +0,0 @@
-# needs-profiler-support
-# ignore-cross-compile
-
-include ../tools.mk
-
-COMPILE_FLAGS=-Copt-level=3 -Clto=fat -Cprofile-generate="$(TMPDIR)"
-
-all:
-	$(RUSTC) $(COMPILE_FLAGS) test.rs
-	$(call RUN,test) || exit 1
-	[ -e "$(TMPDIR)"/default_*.profraw ] || (echo "No .profraw file"; exit 1)
diff --git a/tests/run-make/pgo-gen-lto/rmake.rs b/tests/run-make/pgo-gen-lto/rmake.rs
new file mode 100644
index 00000000000..53d1623bf58
--- /dev/null
+++ b/tests/run-make/pgo-gen-lto/rmake.rs
@@ -0,0 +1,22 @@
+// A simple smoke test: when rustc compiles with profiling enabled, a profraw file
+// should be generated.
+// See https://github.com/rust-lang/rust/pull/48346
+
+//@ needs-profiler-support
+// Reason: this exercises LTO profiling
+//@ ignore-cross-compile
+// Reason: the compiled binary is executed
+
+use run_make_support::{cwd, has_extension, has_prefix, run, rustc, shallow_find_files};
+
+fn main() {
+    rustc().opt_level("3").arg("-Clto=fat").profile_generate(cwd()).input("test.rs").run();
+    run("test");
+    assert_eq!(
+        shallow_find_files(cwd(), |path| {
+            has_prefix(path, "default_") && has_extension(path, "profraw")
+        })
+        .len(),
+        1
+    );
+}
diff --git a/tests/run-make/rust-lld/rmake.rs b/tests/run-make/rust-lld/rmake.rs
index 87477c12230..d0bc19130d7 100644
--- a/tests/run-make/rust-lld/rmake.rs
+++ b/tests/run-make/rust-lld/rmake.rs
@@ -2,15 +2,17 @@
 // see https://github.com/rust-lang/compiler-team/issues/510 for more info
 
 //@ needs-rust-lld
-//@ ignore-msvc
 //@ ignore-s390x lld does not yet support s390x as target
 
 use std::process::Output;
 
 use run_make_support::regex::Regex;
-use run_make_support::rustc;
+use run_make_support::{is_msvc, rustc};
 
 fn main() {
+    // lld-link is used if msvc, otherwise a gnu-compatible lld is used.
+    let linker_version_flag = if is_msvc() { "--version" } else { "-Wl,-v" };
+
     // Opt-in to lld and the self-contained linker, to link with rust-lld. We'll check that by
     // asking the linker to display its version number with a link-arg.
     let output = rustc()
@@ -18,7 +20,7 @@ fn main() {
         .arg("-Zlinker-features=+lld")
         .arg("-Clink-self-contained=+linker")
         .arg("-Zunstable-options")
-        .link_arg("-Wl,-v")
+        .link_arg(linker_version_flag)
         .input("main.rs")
         .run();
     assert!(
@@ -27,10 +29,10 @@ fn main() {
         output.stderr_utf8()
     );
 
-    // It should not be used when we explictly opt-out of lld.
+    // It should not be used when we explicitly opt-out of lld.
     let output = rustc()
         .env("RUSTC_LOG", "rustc_codegen_ssa::back::link=info")
-        .link_arg("-Wl,-v")
+        .link_arg(linker_version_flag)
         .arg("-Zlinker-features=-lld")
         .input("main.rs")
         .run();
@@ -44,7 +46,7 @@ fn main() {
     // times to rustc.
     let output = rustc()
         .env("RUSTC_LOG", "rustc_codegen_ssa::back::link=info")
-        .link_arg("-Wl,-v")
+        .link_arg(linker_version_flag)
         .arg("-Clink-self-contained=+linker")
         .arg("-Zunstable-options")
         .arg("-Zlinker-features=-lld")
diff --git a/tests/run-make/simd-ffi/Makefile b/tests/run-make/simd-ffi/Makefile
deleted file mode 100644
index 29735347041..00000000000
--- a/tests/run-make/simd-ffi/Makefile
+++ /dev/null
@@ -1,47 +0,0 @@
-include ../tools.mk
-
-TARGETS =
-ifeq ($(filter arm,$(LLVM_COMPONENTS)),arm)
-# construct a fairly exhaustive list of platforms that we
-# support. These ones don't follow a pattern
-TARGETS += arm-linux-androideabi arm-unknown-linux-gnueabihf arm-unknown-linux-gnueabi
-endif
-
-ifeq ($(filter x86,$(LLVM_COMPONENTS)),x86)
-X86_ARCHS = i686 x86_64
-else
-X86_ARCHS =
-endif
-
-# these ones do, each OS lists the architectures it supports
-LINUX=$(filter aarch64 mips,$(LLVM_COMPONENTS)) $(X86_ARCHS)
-ifeq ($(filter mips,$(LLVM_COMPONENTS)),mips)
-LINUX += mipsel
-endif
-
-WINDOWS=$(X86_ARCHS)
-# fails with: failed to get iphonesimulator SDK path: no such file or directory
-#IOS=i386 aarch64 armv7
-DARWIN=$(X86_ARCHS)
-
-$(foreach arch,$(LINUX),$(eval TARGETS += $(arch)-unknown-linux-gnu))
-$(foreach arch,$(WINDOWS),$(eval TARGETS += $(arch)-pc-windows-gnu))
-#$(foreach arch,$(IOS),$(eval TARGETS += $(arch)-apple-ios))
-$(foreach arch,$(DARWIN),$(eval TARGETS += $(arch)-apple-darwin))
-
-all: $(TARGETS)
-
-define MK_TARGETS
-# compile the rust file to the given target, but only to asm and IR
-# form, to avoid having to have an appropriate linker.
-#
-# we need some features because the integer SIMD instructions are not
-# enabled by-default for i686 and ARM; these features will be invalid
-# on some platforms, but LLVM just prints a warning so that's fine for
-# now.
-$(1): simd.rs
-	$$(RUSTC) --target=$(1) --emit=llvm-ir,asm simd.rs \
-                -C target-feature='+neon,+sse2' -C extra-filename=-$(1)
-endef
-
-$(foreach targetxxx,$(TARGETS),$(eval $(call MK_TARGETS,$(targetxxx))))
diff --git a/tests/run-make/simd-ffi/rmake.rs b/tests/run-make/simd-ffi/rmake.rs
new file mode 100644
index 00000000000..04990c8bdf4
--- /dev/null
+++ b/tests/run-make/simd-ffi/rmake.rs
@@ -0,0 +1,63 @@
+// Using SIMD types in a program with foreign-function interfaces used to result in an ICE
+// (internal compiler error). Since this was fixed in #21233, it should be checked that
+// compilation of SIMD and FFI together should be successful on all the most common
+// architectures.
+// Note that this test does not check linking or binary execution.
+// See https://github.com/rust-lang/rust/pull/21233
+
+use run_make_support::{llvm_components_contain, rustc};
+
+fn main() {
+    let mut targets = Vec::new();
+    // arm-specific targets.
+    if llvm_components_contain("arm") {
+        targets.append(&mut vec![
+            "arm-linux-androideabi".to_owned(),
+            "arm-unknown-linux-gnueabihf".to_owned(),
+            "arm-unknown-linux-gnueabi".to_owned(),
+        ]);
+    }
+    let mut x86_archs = Vec::new();
+    if llvm_components_contain("x86") {
+        x86_archs.append(&mut vec!["i686", "x86_64"]);
+    }
+    // Linux has all x86 targets, plus aarch64 and mips.
+    let mut extra_targets = x86_archs.clone();
+    if llvm_components_contain("aarch64") {
+        extra_targets.push("aarch64");
+    }
+    if llvm_components_contain("mips") {
+        extra_targets.append(&mut vec!["mips", "mipsel"]);
+    }
+
+    for target in extra_targets {
+        let linux = format!("{target}-unknown-linux-gnu");
+        targets.push(linux);
+    }
+
+    // Windows and Darwin (OSX) only receive x86 targets.
+    let extra_targets = x86_archs.clone();
+    for target in extra_targets {
+        let windows = format!("{target}-pc-windows-gnu");
+        let darwin = format!("{target}-apple-darwin");
+        targets.push(windows);
+        targets.push(darwin);
+    }
+
+    for target in targets {
+        // compile the rust file to the given target, but only to asm and IR
+        // form, to avoid having to have an appropriate linker.
+        //
+        // we need some features because the integer SIMD instructions are not
+        // enabled by-default for i686 and ARM; these features will be invalid
+        // on some platforms, but LLVM just prints a warning so that's fine for
+        // now.
+        rustc()
+            .target(&target)
+            .emit("llvm-ir,asm")
+            .input("simd.rs")
+            .arg("-Ctarget-feature=+neon,+sse")
+            .arg(&format!("-Cextra-filename=-{target}"))
+            .run();
+    }
+}
diff --git a/tests/ui/error-codes/E0283.stderr b/tests/ui/error-codes/E0283.stderr
index fc08395a2b0..381eca5f2a4 100644
--- a/tests/ui/error-codes/E0283.stderr
+++ b/tests/ui/error-codes/E0283.stderr
@@ -7,10 +7,12 @@ LL |     fn create() -> u32;
 LL |     let cont: u32 = Coroutine::create();
    |                     ^^^^^^^^^^^^^^^^^^^ cannot call associated function of trait
    |
-help: use a fully-qualified path to a specific available implementation
+help: use a fully-qualified path to one of the available implementations
    |
-LL |     let cont: u32 = </* self type */ as Coroutine>::create();
-   |                     +++++++++++++++++++          +
+LL |     let cont: u32 = <Impl as Coroutine>::create();
+   |                     ++++++++          +
+LL |     let cont: u32 = <AnotherImpl as Coroutine>::create();
+   |                     +++++++++++++++          +
 
 error[E0283]: type annotations needed
   --> $DIR/E0283.rs:35:24
diff --git a/tests/ui/error-codes/E0790.stderr b/tests/ui/error-codes/E0790.stderr
index 6338a10b6af..106554b2425 100644
--- a/tests/ui/error-codes/E0790.stderr
+++ b/tests/ui/error-codes/E0790.stderr
@@ -63,10 +63,12 @@ LL |     fn my_fn();
 LL |     MyTrait2::my_fn();
    |     ^^^^^^^^^^^^^^^^^ cannot call associated function of trait
    |
-help: use a fully-qualified path to a specific available implementation
+help: use a fully-qualified path to one of the available implementations
    |
-LL |     </* self type */ as MyTrait2>::my_fn();
-   |     +++++++++++++++++++         +
+LL |     <Impl1 as MyTrait2>::my_fn();
+   |     +++++++++         +
+LL |     <Impl2 as MyTrait2>::my_fn();
+   |     +++++++++         +
 
 error: aborting due to 5 previous errors
 
diff --git a/tests/ui/impl-trait/in-trait/cannot-capture-intersection.rs b/tests/ui/impl-trait/in-trait/cannot-capture-intersection.rs
new file mode 100644
index 00000000000..d7b62436d2d
--- /dev/null
+++ b/tests/ui/impl-trait/in-trait/cannot-capture-intersection.rs
@@ -0,0 +1,29 @@
+#![feature(precise_capturing)]
+
+use std::future::Future;
+use std::pin::Pin;
+
+trait MyTrait {
+    fn foo<'a, 'b>(&'a self, x: &'b i32) -> impl Future<Output = i32>;
+}
+
+trait ErasedMyTrait {
+    fn foo<'life0, 'life1, 'dynosaur>(&'life0 self, x: &'life1 i32)
+    -> Pin<Box<dyn Future<Output = i32> + 'dynosaur>>
+    where
+        'life0: 'dynosaur,
+        'life1: 'dynosaur;
+}
+
+struct DynMyTrait<T: ErasedMyTrait> {
+    ptr: T,
+}
+
+impl<T: ErasedMyTrait> MyTrait for DynMyTrait<T> {
+    fn foo<'a, 'b>(&'a self, x: &'b i32) -> impl Future<Output = i32> {
+        self.ptr.foo(x)
+        //~^ ERROR hidden type for `impl Future<Output = i32>` captures lifetime that does not appear in bounds
+    }
+}
+
+fn main() {}
diff --git a/tests/ui/impl-trait/in-trait/cannot-capture-intersection.stderr b/tests/ui/impl-trait/in-trait/cannot-capture-intersection.stderr
new file mode 100644
index 00000000000..92ef66c5504
--- /dev/null
+++ b/tests/ui/impl-trait/in-trait/cannot-capture-intersection.stderr
@@ -0,0 +1,13 @@
+error[E0700]: hidden type for `impl Future<Output = i32>` captures lifetime that does not appear in bounds
+  --> $DIR/cannot-capture-intersection.rs:24:9
+   |
+LL |     fn foo<'a, 'b>(&'a self, x: &'b i32) -> impl Future<Output = i32> {
+   |                                             ------------------------- opaque type defined here
+LL |         self.ptr.foo(x)
+   |         ^^^^^^^^^^^^^^^
+   |
+   = note: hidden type `Pin<Box<dyn Future<Output = i32>>>` captures lifetime `'_`
+
+error: aborting due to 1 previous error
+
+For more information about this error, try `rustc --explain E0700`.
diff --git a/tests/ui/impl-trait/multiple-lifetimes/ordinary-bounds-unrelated.stderr b/tests/ui/impl-trait/multiple-lifetimes/ordinary-bounds-unrelated.stderr
index 4d4ba58c974..b7cee7d0b1f 100644
--- a/tests/ui/impl-trait/multiple-lifetimes/ordinary-bounds-unrelated.stderr
+++ b/tests/ui/impl-trait/multiple-lifetimes/ordinary-bounds-unrelated.stderr
@@ -2,17 +2,12 @@ error[E0700]: hidden type for `impl Trait<'d, 'e>` captures lifetime that does n
   --> $DIR/ordinary-bounds-unrelated.rs:28:33
    |
 LL | fn upper_bounds<'a, 'b, 'c, 'd, 'e>(a: Ordinary<'a>, b: Ordinary<'b>) -> impl Trait<'d, 'e>
-   |                     --                                                   ------------------ opaque type defined here
-   |                     |
-   |                     hidden type `Ordinary<'b>` captures the lifetime `'b` as defined here
+   |                                                                          ------------------ opaque type defined here
 ...
 LL |     if condition() { a } else { b }
    |                                 ^
    |
-help: to declare that `impl Trait<'d, 'e>` captures `'b`, you can add an explicit `'b` lifetime bound
-   |
-LL | fn upper_bounds<'a, 'b, 'c, 'd, 'e>(a: Ordinary<'a>, b: Ordinary<'b>) -> impl Trait<'d, 'e> + 'b
-   |                                                                                             ++++
+   = note: hidden type `Ordinary<'_>` captures lifetime `'_`
 
 error: aborting due to 1 previous error
 
diff --git a/tests/ui/impl-trait/multiple-lifetimes/ordinary-bounds-unsuited.stderr b/tests/ui/impl-trait/multiple-lifetimes/ordinary-bounds-unsuited.stderr
index 060eaa7e64a..d1190da6c9f 100644
--- a/tests/ui/impl-trait/multiple-lifetimes/ordinary-bounds-unsuited.stderr
+++ b/tests/ui/impl-trait/multiple-lifetimes/ordinary-bounds-unsuited.stderr
@@ -2,17 +2,12 @@ error[E0700]: hidden type for `impl Trait<'a, 'b>` captures lifetime that does n
   --> $DIR/ordinary-bounds-unsuited.rs:31:33
    |
 LL | fn upper_bounds<'a, 'b>(a: Ordinary<'a>, b: Ordinary<'b>) -> impl Trait<'a, 'b>
-   |                     --                                       ------------------ opaque type defined here
-   |                     |
-   |                     hidden type `Ordinary<'b>` captures the lifetime `'b` as defined here
+   |                                                              ------------------ opaque type defined here
 ...
 LL |     if condition() { a } else { b }
    |                                 ^
    |
-help: to declare that `impl Trait<'a, 'b>` captures `'b`, you can add an explicit `'b` lifetime bound
-   |
-LL | fn upper_bounds<'a, 'b>(a: Ordinary<'a>, b: Ordinary<'b>) -> impl Trait<'a, 'b> + 'b
-   |                                                                                 ++++
+   = note: hidden type `Ordinary<'_>` captures lifetime `'_`
 
 error: aborting due to 1 previous error
 
diff --git a/tests/ui/suggestions/lifetimes/explicit-lifetime-suggestion-in-proper-span-issue-121267.stderr b/tests/ui/suggestions/lifetimes/explicit-lifetime-suggestion-in-proper-span-issue-121267.stderr
index aeeec3aca34..3a1f685f16b 100644
--- a/tests/ui/suggestions/lifetimes/explicit-lifetime-suggestion-in-proper-span-issue-121267.stderr
+++ b/tests/ui/suggestions/lifetimes/explicit-lifetime-suggestion-in-proper-span-issue-121267.stderr
@@ -2,18 +2,13 @@ error[E0700]: hidden type for `impl Iterator<Item = i32>` captures lifetime that
   --> $DIR/explicit-lifetime-suggestion-in-proper-span-issue-121267.rs:7:5
    |
 LL |   fn bar(src: &crate::Foo) -> impl Iterator<Item = i32> {
-   |                ----------     ------------------------- opaque type defined here
-   |                |
-   |                hidden type `FilterMap<std::slice::Iter<'static, i32>, {closure@$DIR/explicit-lifetime-suggestion-in-proper-span-issue-121267.rs:9:21: 9:24}>` captures the anonymous lifetime defined here
+   |                               ------------------------- opaque type defined here
 LL | /     [0].into_iter()
 LL | |
 LL | |         .filter_map(|_| foo(src))
    | |_________________________________^
    |
-help: to declare that `impl Iterator<Item = i32>` captures `'_`, you can introduce a named lifetime parameter `'a`
-   |
-LL | fn bar<'a>(src: &'a crate::Foo<'a>) -> impl Iterator<Item = i32> + 'a  {
-   |       ++++       ++           ++++                               ++++
+   = note: hidden type `FilterMap<std::slice::Iter<'static, i32>, {closure@$DIR/explicit-lifetime-suggestion-in-proper-span-issue-121267.rs:9:21: 9:24}>` captures lifetime `'_`
 
 error: aborting due to 1 previous error