Merge pull request #4458 from rust-lang/rustup-2025-07-10

Automatic Rustup

13 files changed, 157 insertions, 62 deletions

diff --git a/src/bootstrap/configure.py b/src/bootstrap/configure.py
index c077555b906..b05a5cc8b81 100755
--- a/src/bootstrap/configure.py
+++ b/src/bootstrap/configure.py
@@ -739,19 +739,29 @@ def configure_file(sections, top_level_keys, targets, config):
 
 
 def write_uncommented(target, f):
+    """Writes each block in 'target' that is not composed entirely of comments to 'f'.
+
+    A block is a sequence of non-empty lines separated by empty lines.
+    """
     block = []
-    is_comment = True
+
+    def flush(last):
+        # If the block is entirely made of comments, ignore it
+        entire_block_comments = all(ln.startswith("#") or ln == "" for ln in block)
+        if not entire_block_comments and len(block) > 0:
+            for line in block:
+                f.write(line + "\n")
+            # Required to output a newline before the start of a new section
+            if last:
+                f.write("\n")
+        block.clear()
 
     for line in target:
         block.append(line)
         if len(line) == 0:
-            if not is_comment:
-                for ln in block:
-                    f.write(ln + "\n")
-            block = []
-            is_comment = True
-            continue
-        is_comment = is_comment and line.startswith("#")
+            flush(last=False)
+
+    flush(last=True)
     return f
 
 
diff --git a/src/bootstrap/src/core/build_steps/compile.rs b/src/bootstrap/src/core/build_steps/compile.rs
index 3e2bdc2d6b5..0587d21ecc2 100644
--- a/src/bootstrap/src/core/build_steps/compile.rs
+++ b/src/bootstrap/src/core/build_steps/compile.rs
@@ -1369,9 +1369,7 @@ pub fn rustc_cargo_env(
     }
 
     // Enable rustc's env var for `rust-lld` when requested.
-    if builder.config.lld_enabled
-        && (builder.config.channel == "dev" || builder.config.channel == "nightly")
-    {
+    if builder.config.lld_enabled {
         cargo.env("CFG_USE_SELF_CONTAINED_LINKER", "1");
     }
 
@@ -2059,14 +2057,20 @@ impl Step for Assemble {
                 trace!("llvm-bitcode-linker enabled, installing");
                 let llvm_bitcode_linker =
                     builder.ensure(crate::core::build_steps::tool::LlvmBitcodeLinker {
-                        compiler,
+                        build_compiler: compiler,
                         target: target_compiler.host,
-                        extra_features: vec![],
                     });
+
+                // Copy the llvm-bitcode-linker to the self-contained binary directory
+                let bindir_self_contained = builder
+                    .sysroot(compiler)
+                    .join(format!("lib/rustlib/{}/bin/self-contained", compiler.host));
                 let tool_exe = exe("llvm-bitcode-linker", target_compiler.host);
+
+                t!(fs::create_dir_all(&bindir_self_contained));
                 builder.copy_link(
                     &llvm_bitcode_linker.tool_path,
-                    &libdir_bin.join(tool_exe),
+                    &bindir_self_contained.join(tool_exe),
                     FileType::Executable,
                 );
             }
diff --git a/src/bootstrap/src/core/build_steps/dist.rs b/src/bootstrap/src/core/build_steps/dist.rs
index 25b7e5a1b5d..8b2d65ace50 100644
--- a/src/bootstrap/src/core/build_steps/dist.rs
+++ b/src/bootstrap/src/core/build_steps/dist.rs
@@ -2375,7 +2375,7 @@ impl Step for LlvmBitcodeLinker {
         builder.ensure(compile::Rustc::new(compiler, target));
 
         let llbc_linker =
-            builder.ensure(tool::LlvmBitcodeLinker { compiler, target, extra_features: vec![] });
+            builder.ensure(tool::LlvmBitcodeLinker { build_compiler: compiler, target });
 
         let self_contained_bin_dir = format!("lib/rustlib/{}/bin/self-contained", target.triple);
 
diff --git a/src/bootstrap/src/core/build_steps/test.rs b/src/bootstrap/src/core/build_steps/test.rs
index a5b7b22aba8..716bef3f38c 100644
--- a/src/bootstrap/src/core/build_steps/test.rs
+++ b/src/bootstrap/src/core/build_steps/test.rs
@@ -262,7 +262,13 @@ impl Step for Cargotest {
             .args(builder.config.test_args())
             .env("RUSTC", builder.rustc(compiler))
             .env("RUSTDOC", builder.rustdoc(compiler));
-        add_rustdoc_cargo_linker_args(&mut cmd, builder, compiler.host, LldThreads::No);
+        add_rustdoc_cargo_linker_args(
+            &mut cmd,
+            builder,
+            compiler.host,
+            LldThreads::No,
+            compiler.stage,
+        );
         cmd.delay_failure().run(builder);
     }
 }
@@ -857,7 +863,7 @@ impl Step for RustdocTheme {
             .env("CFG_RELEASE_CHANNEL", &builder.config.channel)
             .env("RUSTDOC_REAL", builder.rustdoc(self.compiler))
             .env("RUSTC_BOOTSTRAP", "1");
-        cmd.args(linker_args(builder, self.compiler.host, LldThreads::No));
+        cmd.args(linker_args(builder, self.compiler.host, LldThreads::No, self.compiler.stage));
 
         cmd.delay_failure().run(builder);
     }
@@ -1033,7 +1039,13 @@ impl Step for RustdocGUI {
         cmd.env("RUSTDOC", builder.rustdoc(self.compiler))
             .env("RUSTC", builder.rustc(self.compiler));
 
-        add_rustdoc_cargo_linker_args(&mut cmd, builder, self.compiler.host, LldThreads::No);
+        add_rustdoc_cargo_linker_args(
+            &mut cmd,
+            builder,
+            self.compiler.host,
+            LldThreads::No,
+            self.compiler.stage,
+        );
 
         for path in &builder.paths {
             if let Some(p) = helpers::is_valid_test_suite_arg(path, "tests/rustdoc-gui", builder) {
@@ -1812,7 +1824,7 @@ NOTE: if you're sure you want to do this, please open an issue as to why. In the
         }
 
         let mut hostflags = flags.clone();
-        hostflags.extend(linker_flags(builder, compiler.host, LldThreads::No));
+        hostflags.extend(linker_flags(builder, compiler.host, LldThreads::No, compiler.stage));
 
         let mut targetflags = flags;
 
diff --git a/src/bootstrap/src/core/build_steps/tool.rs b/src/bootstrap/src/core/build_steps/tool.rs
index b05b34b9b22..5de1b472d79 100644
--- a/src/bootstrap/src/core/build_steps/tool.rs
+++ b/src/bootstrap/src/core/build_steps/tool.rs
@@ -910,6 +910,13 @@ impl Step for LldWrapper {
 
         tool_result
     }
+
+    fn metadata(&self) -> Option<StepMetadata> {
+        Some(
+            StepMetadata::build("LldWrapper", self.target_compiler.host)
+                .built_by(self.build_compiler),
+        )
+    }
 }
 
 #[derive(Debug, Clone, Hash, PartialEq, Eq)]
@@ -1014,9 +1021,8 @@ impl Step for RustAnalyzerProcMacroSrv {
 
 #[derive(Debug, Clone, Hash, PartialEq, Eq)]
 pub struct LlvmBitcodeLinker {
-    pub compiler: Compiler,
+    pub build_compiler: Compiler,
     pub target: TargetSelection,
-    pub extra_features: Vec<String>,
 }
 
 impl Step for LlvmBitcodeLinker {
@@ -1032,8 +1038,9 @@ impl Step for LlvmBitcodeLinker {
 
     fn make_run(run: RunConfig<'_>) {
         run.builder.ensure(LlvmBitcodeLinker {
-            compiler: run.builder.compiler(run.builder.top_stage, run.builder.config.host_target),
-            extra_features: Vec::new(),
+            build_compiler: run
+                .builder
+                .compiler(run.builder.top_stage, run.builder.config.host_target),
             target: run.target,
         });
     }
@@ -1043,35 +1050,22 @@ impl Step for LlvmBitcodeLinker {
         instrument(level = "debug", name = "LlvmBitcodeLinker::run", skip_all)
     )]
     fn run(self, builder: &Builder<'_>) -> ToolBuildResult {
-        let tool_result = builder.ensure(ToolBuild {
-            compiler: self.compiler,
+        builder.ensure(ToolBuild {
+            compiler: self.build_compiler,
             target: self.target,
             tool: "llvm-bitcode-linker",
             mode: Mode::ToolRustc,
             path: "src/tools/llvm-bitcode-linker",
             source_type: SourceType::InTree,
-            extra_features: self.extra_features,
+            extra_features: vec![],
             allow_features: "",
             cargo_args: Vec::new(),
             artifact_kind: ToolArtifactKind::Binary,
-        });
+        })
+    }
 
-        if tool_result.target_compiler.stage > 0 {
-            let bindir_self_contained = builder
-                .sysroot(tool_result.target_compiler)
-                .join(format!("lib/rustlib/{}/bin/self-contained", self.target.triple));
-            t!(fs::create_dir_all(&bindir_self_contained));
-            let bin_destination = bindir_self_contained
-                .join(exe("llvm-bitcode-linker", tool_result.target_compiler.host));
-            builder.copy_link(&tool_result.tool_path, &bin_destination, FileType::Executable);
-            ToolBuildResult {
-                tool_path: bin_destination,
-                build_compiler: tool_result.build_compiler,
-                target_compiler: tool_result.target_compiler,
-            }
-        } else {
-            tool_result
-        }
+    fn metadata(&self) -> Option<StepMetadata> {
+        Some(StepMetadata::build("LlvmBitcodeLinker", self.target).built_by(self.build_compiler))
     }
 }
 
diff --git a/src/bootstrap/src/core/builder/cargo.rs b/src/bootstrap/src/core/builder/cargo.rs
index deb7106f185..065d7e45e0f 100644
--- a/src/bootstrap/src/core/builder/cargo.rs
+++ b/src/bootstrap/src/core/builder/cargo.rs
@@ -115,7 +115,7 @@ impl Cargo {
             // No need to configure the target linker for these command types.
             Kind::Clean | Kind::Check | Kind::Suggest | Kind::Format | Kind::Setup => {}
             _ => {
-                cargo.configure_linker(builder);
+                cargo.configure_linker(builder, mode);
             }
         }
 
@@ -209,7 +209,7 @@ impl Cargo {
 
     // FIXME(onur-ozkan): Add coverage to make sure modifications to this function
     // doesn't cause cache invalidations (e.g., #130108).
-    fn configure_linker(&mut self, builder: &Builder<'_>) -> &mut Cargo {
+    fn configure_linker(&mut self, builder: &Builder<'_>, mode: Mode) -> &mut Cargo {
         let target = self.target;
         let compiler = self.compiler;
 
@@ -264,7 +264,12 @@ impl Cargo {
             }
         }
 
-        for arg in linker_args(builder, compiler.host, LldThreads::Yes) {
+        // We use the snapshot compiler when building host code (build scripts/proc macros) of
+        // `Mode::Std` tools, so we need to determine the current stage here to pass the proper
+        // linker args (e.g. -C vs -Z).
+        // This should stay synchronized with the [cargo] function.
+        let host_stage = if mode == Mode::Std { 0 } else { compiler.stage };
+        for arg in linker_args(builder, compiler.host, LldThreads::Yes, host_stage) {
             self.hostflags.arg(&arg);
         }
 
@@ -274,10 +279,10 @@ impl Cargo {
         }
         // We want to set -Clinker using Cargo, therefore we only call `linker_flags` and not
         // `linker_args` here.
-        for flag in linker_flags(builder, target, LldThreads::Yes) {
+        for flag in linker_flags(builder, target, LldThreads::Yes, compiler.stage) {
             self.rustflags.arg(&flag);
         }
-        for arg in linker_args(builder, target, LldThreads::Yes) {
+        for arg in linker_args(builder, target, LldThreads::Yes, compiler.stage) {
             self.rustdocflags.arg(&arg);
         }
 
diff --git a/src/bootstrap/src/core/builder/mod.rs b/src/bootstrap/src/core/builder/mod.rs
index b96a988cde3..7464327fde9 100644
--- a/src/bootstrap/src/core/builder/mod.rs
+++ b/src/bootstrap/src/core/builder/mod.rs
@@ -1599,7 +1599,7 @@ You have to build a stage1 compiler for `{}` first, and then use it to build a s
             cmd.arg("-Dwarnings");
         }
         cmd.arg("-Znormalize-docs");
-        cmd.args(linker_args(self, compiler.host, LldThreads::Yes));
+        cmd.args(linker_args(self, compiler.host, LldThreads::Yes, compiler.stage));
         cmd
     }
 
diff --git a/src/bootstrap/src/core/builder/tests.rs b/src/bootstrap/src/core/builder/tests.rs
index 1d5690a8197..bbcb58fca14 100644
--- a/src/bootstrap/src/core/builder/tests.rs
+++ b/src/bootstrap/src/core/builder/tests.rs
@@ -758,6 +758,58 @@ mod snapshot {
     }
 
     #[test]
+    fn build_compiler_tools() {
+        let ctx = TestCtx::new();
+        insta::assert_snapshot!(
+            ctx
+                .config("build")
+                .stage(2)
+                .args(&["--set", "rust.lld=true", "--set", "rust.llvm-bitcode-linker=true"])
+                .render_steps(), @r"
+        [build] llvm <host>
+        [build] rustc 0 <host> -> rustc 1 <host>
+        [build] rustc 0 <host> -> LldWrapper 1 <host>
+        [build] rustc 1 <host> -> LlvmBitcodeLinker 2 <host>
+        [build] rustc 1 <host> -> std 1 <host>
+        [build] rustc 1 <host> -> rustc 2 <host>
+        [build] rustc 1 <host> -> LldWrapper 2 <host>
+        [build] rustc 2 <host> -> LlvmBitcodeLinker 3 <host>
+        [build] rustc 2 <host> -> std 2 <host>
+        [build] rustdoc 1 <host>
+        "
+        );
+    }
+
+    #[test]
+    fn build_compiler_tools_cross() {
+        let ctx = TestCtx::new();
+        insta::assert_snapshot!(
+            ctx
+                .config("build")
+                .stage(2)
+                .args(&["--set", "rust.lld=true", "--set", "rust.llvm-bitcode-linker=true"])
+                .hosts(&[TEST_TRIPLE_1])
+                .render_steps(), @r"
+        [build] llvm <host>
+        [build] rustc 0 <host> -> rustc 1 <host>
+        [build] rustc 0 <host> -> LldWrapper 1 <host>
+        [build] rustc 1 <host> -> LlvmBitcodeLinker 2 <host>
+        [build] rustc 1 <host> -> std 1 <host>
+        [build] rustc 1 <host> -> rustc 2 <host>
+        [build] rustc 1 <host> -> LldWrapper 2 <host>
+        [build] rustc 2 <host> -> LlvmBitcodeLinker 3 <host>
+        [build] rustc 1 <host> -> std 1 <target1>
+        [build] rustc 2 <host> -> std 2 <target1>
+        [build] llvm <target1>
+        [build] rustc 1 <host> -> rustc 2 <target1>
+        [build] rustc 1 <host> -> LldWrapper 2 <target1>
+        [build] rustc 2 <target1> -> LlvmBitcodeLinker 3 <target1>
+        [build] rustdoc 1 <target1>
+        "
+        );
+    }
+
+    #[test]
     fn build_library_no_explicit_stage() {
         let ctx = TestCtx::new();
         insta::assert_snapshot!(
@@ -1040,6 +1092,7 @@ mod snapshot {
         [build] rustc 0 <host> -> cargo-clippy 1 <host>
         [build] rustc 0 <host> -> miri 1 <host>
         [build] rustc 0 <host> -> cargo-miri 1 <host>
+        [build] rustc 1 <host> -> LlvmBitcodeLinker 2 <host>
         ");
     }
 
@@ -1230,6 +1283,7 @@ mod snapshot {
         [build] rustc 0 <host> -> cargo-clippy 1 <target1>
         [build] rustc 0 <host> -> miri 1 <target1>
         [build] rustc 0 <host> -> cargo-miri 1 <target1>
+        [build] rustc 1 <host> -> LlvmBitcodeLinker 2 <target1>
         ");
     }
 
diff --git a/src/bootstrap/src/core/config/flags.rs b/src/bootstrap/src/core/config/flags.rs
index bfc06f90d4f..19e0d3413bb 100644
--- a/src/bootstrap/src/core/config/flags.rs
+++ b/src/bootstrap/src/core/config/flags.rs
@@ -383,7 +383,10 @@ pub enum Subcommand {
         bless: bool,
         #[arg(long)]
         /// comma-separated list of other files types to check (accepts py, py:lint,
-        /// py:fmt, shell, shell:lint, cpp, cpp:fmt, spellcheck, spellcheck:fix)
+        /// py:fmt, shell, shell:lint, cpp, cpp:fmt, spellcheck)
+        ///
+        /// Any argument can be prefixed with "auto:" to only run if
+        /// relevant files are modified (eg. "auto:py").
         extra_checks: Option<String>,
         #[arg(long)]
         /// rerun tests even if the inputs are unchanged
diff --git a/src/bootstrap/src/core/config/toml/rust.rs b/src/bootstrap/src/core/config/toml/rust.rs
index ac5eaea3bcb..0fae235bb93 100644
--- a/src/bootstrap/src/core/config/toml/rust.rs
+++ b/src/bootstrap/src/core/config/toml/rust.rs
@@ -619,7 +619,6 @@ impl Config {
         // build our internal lld and use it as the default linker, by setting the `rust.lld` config
         // to true by default:
         // - on the `x86_64-unknown-linux-gnu` target
-        // - on the `dev` and `nightly` channels
         // - when building our in-tree llvm (i.e. the target has not set an `llvm-config`), so that
         //   we're also able to build the corresponding lld
         // - or when using an external llvm that's downloaded from CI, which also contains our prebuilt
@@ -628,9 +627,7 @@ 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.host_target.triple == "x86_64-unknown-linux-gnu"
-            && self.hosts == [self.host_target]
-            && (self.channel == "dev" || self.channel == "nightly")
+        if self.host_target.triple == "x86_64-unknown-linux-gnu" && self.hosts == [self.host_target]
         {
             let no_llvm_config = self
                 .target_config
diff --git a/src/bootstrap/src/utils/change_tracker.rs b/src/bootstrap/src/utils/change_tracker.rs
index 424f211c7d4..29591edc9cc 100644
--- a/src/bootstrap/src/utils/change_tracker.rs
+++ b/src/bootstrap/src/utils/change_tracker.rs
@@ -461,4 +461,9 @@ pub const CONFIG_CHANGE_HISTORY: &[ChangeInfo] = &[
         severity: ChangeSeverity::Warning,
         summary: "`download-rustc` has been temporarily disabled for the library profile due to implementation bugs (see #142505).",
     },
+    ChangeInfo {
+        change_id: 143398,
+        severity: ChangeSeverity::Info,
+        summary: "The --extra-checks flag now supports prefixing any check with `auto:` to only run it if relevant files are modified",
+    },
 ];
diff --git a/src/bootstrap/src/utils/helpers.rs b/src/bootstrap/src/utils/helpers.rs
index 3c5f612daa7..eb00ed566c2 100644
--- a/src/bootstrap/src/utils/helpers.rs
+++ b/src/bootstrap/src/utils/helpers.rs
@@ -404,8 +404,9 @@ pub fn linker_args(
     builder: &Builder<'_>,
     target: TargetSelection,
     lld_threads: LldThreads,
+    stage: u32,
 ) -> Vec<String> {
-    let mut args = linker_flags(builder, target, lld_threads);
+    let mut args = linker_flags(builder, target, lld_threads, stage);
 
     if let Some(linker) = builder.linker(target) {
         args.push(format!("-Clinker={}", linker.display()));
@@ -420,19 +421,30 @@ pub fn linker_flags(
     builder: &Builder<'_>,
     target: TargetSelection,
     lld_threads: LldThreads,
+    stage: u32,
 ) -> Vec<String> {
     let mut args = vec![];
     if !builder.is_lld_direct_linker(target) && builder.config.lld_mode.is_used() {
         match builder.config.lld_mode {
             LldMode::External => {
-                args.push("-Zlinker-features=+lld".to_string());
-                // FIXME(kobzol): remove this flag once MCP510 gets stabilized
+                // cfg(bootstrap) - remove the stage 0 check after updating the bootstrap compiler:
+                // `-Clinker-features` has been stabilized.
+                if stage == 0 {
+                    args.push("-Zlinker-features=+lld".to_string());
+                } else {
+                    args.push("-Clinker-features=+lld".to_string());
+                }
                 args.push("-Zunstable-options".to_string());
             }
             LldMode::SelfContained => {
-                args.push("-Zlinker-features=+lld".to_string());
+                // cfg(bootstrap) - remove the stage 0 check after updating the bootstrap compiler:
+                // `-Clinker-features` has been stabilized.
+                if stage == 0 {
+                    args.push("-Zlinker-features=+lld".to_string());
+                } else {
+                    args.push("-Clinker-features=+lld".to_string());
+                }
                 args.push("-Clink-self-contained=+linker".to_string());
-                // FIXME(kobzol): remove this flag once MCP510 gets stabilized
                 args.push("-Zunstable-options".to_string());
             }
             LldMode::Unused => unreachable!(),
@@ -453,8 +465,9 @@ pub fn add_rustdoc_cargo_linker_args(
     builder: &Builder<'_>,
     target: TargetSelection,
     lld_threads: LldThreads,
+    stage: u32,
 ) {
-    let args = linker_args(builder, target, lld_threads);
+    let args = linker_args(builder, target, lld_threads, stage);
     let mut flags = cmd
         .get_envs()
         .find_map(|(k, v)| if k == OsStr::new("RUSTDOCFLAGS") { v } else { None })
diff --git a/src/bootstrap/src/utils/tests/mod.rs b/src/bootstrap/src/utils/tests/mod.rs
index 59c169b0f2b..5b568c1df5b 100644
--- a/src/bootstrap/src/utils/tests/mod.rs
+++ b/src/bootstrap/src/utils/tests/mod.rs
@@ -96,8 +96,6 @@ impl ConfigBuilder {
         // in-tree LLVM from sources.
         self.args.push("--set".to_string());
         self.args.push("llvm.download-ci-llvm=false".to_string());
-        self.args.push("--set".to_string());
-        self.args.push(format!("target.'{}'.llvm-config=false", get_host_target()));
 
         // Do not mess with the local rustc checkout build directory
         self.args.push("--build-dir".to_string());