Rollup of 6 pull requests

compiler/rustc_codegen_gcc/example/mini_core.rs

@@ -4,7 +4,7 @@
     thread_local
 )]
 #![no_core]
-#![allow(dead_code, internal_features)]
+#![allow(dead_code, internal_features, ambiguous_wide_pointer_comparisons)]
 
 #[no_mangle]
 unsafe extern "C" fn _Unwind_Resume() {

compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp

@@ -841,7 +841,11 @@ LLVMRustOptimize(
         // cargo run tests in multhreading mode by default
         // so use atomics for coverage counters
         Options.Atomic = true;
+#if LLVM_VERSION_GE(18, 0)
+        MPM.addPass(InstrProfilingLoweringPass(Options, false));
+#else
         MPM.addPass(InstrProfiling(Options, false));
+#endif
       }
     );
   }

src/bootstrap/src/bin/main.rs

@@ -10,8 +10,9 @@ use std::io::Write;
 #[cfg(all(any(unix, windows), not(target_os = "solaris")))]
 use std::process;
 use std::{
-    env, fs,
-    io::{self, IsTerminal},
+    env,
+    fs::{self, OpenOptions},
+    io::{self, BufRead, BufReader, IsTerminal},
 };
 
 use bootstrap::{
@@ -79,6 +80,9 @@ fn main() {
     }
 
     let pre_commit = config.src.join(".git").join("hooks").join("pre-commit");
+    let dump_bootstrap_shims = config.dump_bootstrap_shims;
+    let out_dir = config.out.clone();
+
     Build::new(config).build();
 
     if suggest_setup {
@@ -107,6 +111,29 @@ fn main() {
     if suggest_setup || changelog_suggestion.is_some() {
         println!("NOTE: this message was printed twice to make it more likely to be seen");
     }
+
+    if dump_bootstrap_shims {
+        let dump_dir = out_dir.join("bootstrap-shims-dump");
+        assert!(dump_dir.exists());
+
+        for entry in walkdir::WalkDir::new(&dump_dir) {
+            let entry = t!(entry);
+
+            if !entry.file_type().is_file() {
+                continue;
+            }
+
+            let file = t!(fs::File::open(&entry.path()));
+
+            // To ensure deterministic results we must sort the dump lines.
+            // This is necessary because the order of rustc invocations different
+            // almost all the time.
+            let mut lines: Vec<String> = t!(BufReader::new(&file).lines().collect());
+            lines.sort_by_key(|t| t.to_lowercase());
+            let mut file = t!(OpenOptions::new().write(true).truncate(true).open(&entry.path()));
+            t!(file.write_all(lines.join("\n").as_bytes()));
+        }
+    }
 }
 
 fn check_version(config: &Config) -> Option<String> {

src/bootstrap/src/bin/rustc.rs

@@ -32,9 +32,7 @@ fn main() {
     let args = env::args_os().skip(1).collect::<Vec<_>>();
     let arg = |name| args.windows(2).find(|args| args[0] == name).and_then(|args| args[1].to_str());
 
-    // We don't use the stage in this shim, but let's parse it to make sure that we're invoked
-    // by bootstrap, or that we provide a helpful error message if not.
-    bin_helpers::parse_rustc_stage();
+    let stage = bin_helpers::parse_rustc_stage();
     let verbose = bin_helpers::parse_rustc_verbose();
 
     // Detect whether or not we're a build script depending on whether --target
@@ -214,6 +212,8 @@ fn main() {
         }
     }
 
+    bin_helpers::maybe_dump(format!("stage{stage}-rustc"), &cmd);
+
     let start = Instant::now();
     let (child, status) = {
         let errmsg = format!("\nFailed to run:\n{cmd:?}\n-------------");

src/bootstrap/src/bin/rustdoc.rs

@@ -62,6 +62,8 @@ fn main() {
     cmd.arg("-Zunstable-options");
     cmd.arg("--check-cfg=cfg(bootstrap)");
 
+    bin_helpers::maybe_dump(format!("stage{stage}-rustdoc"), &cmd);
+
     if verbose > 1 {
         eprintln!(
             "rustdoc command: {:?}={:?} {:?}",

src/bootstrap/src/core/build_steps/clean.rs

@@ -146,6 +146,7 @@ fn clean_default(build: &Build) {
     rm_rf(&build.out.join("tmp"));
     rm_rf(&build.out.join("dist"));
     rm_rf(&build.out.join("bootstrap").join(".last-warned-change-id"));
+    rm_rf(&build.out.join("bootstrap-shims-dump"));
     rm_rf(&build.out.join("rustfmt.stamp"));
 
     for host in &build.hosts {

src/bootstrap/src/core/builder.rs

@@ -18,12 +18,12 @@ use crate::core::build_steps::tool::{self, SourceType};
 use crate::core::build_steps::{check, clean, compile, dist, doc, install, run, setup, test};
 use crate::core::config::flags::{Color, Subcommand};
 use crate::core::config::{DryRun, SplitDebuginfo, TargetSelection};
+use crate::prepare_behaviour_dump_dir;
 use crate::utils::cache::{Cache, Interned, INTERNER};
 use crate::utils::helpers::{self, add_dylib_path, add_link_lib_path, exe, linker_args};
 use crate::utils::helpers::{libdir, linker_flags, output, t, LldThreads};
-use crate::Crate;
 use crate::EXTRA_CHECK_CFGS;
-use crate::{Build, CLang, DocTests, GitRepo, Mode};
+use crate::{Build, CLang, Crate, DocTests, GitRepo, Mode};
 
 pub use crate::Compiler;
 
@@ -1788,6 +1788,16 @@ impl<'a> Builder<'a> {
 
         // Enable usage of unstable features
         cargo.env("RUSTC_BOOTSTRAP", "1");
+
+        if self.config.dump_bootstrap_shims {
+            prepare_behaviour_dump_dir(&self.build);
+
+            cargo
+                .env("DUMP_BOOTSTRAP_SHIMS", self.build.out.join("bootstrap-shims-dump"))
+                .env("BUILD_OUT", &self.build.out)
+                .env("CARGO_HOME", t!(home::cargo_home()));
+        };
+
         self.add_rust_test_threads(&mut cargo);
 
         // Almost all of the crates that we compile as part of the bootstrap may

src/bootstrap/src/core/config/config.rs

@@ -193,6 +193,7 @@ pub struct Config {
     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.
     pub free_args: Vec<String>,
@@ -1210,6 +1211,7 @@ impl Config {
         config.cmd = flags.cmd;
         config.incremental = flags.incremental;
         config.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;
         config.color = flags.color;

src/bootstrap/src/core/config/flags.rs

@@ -85,6 +85,9 @@ pub struct Flags {
     #[arg(global(true), long)]
     /// dry run; don't build anything
     pub dry_run: bool,
+    /// Indicates whether to dump the work done from bootstrap shims
+    #[arg(global(true), long)]
+    pub dump_bootstrap_shims: bool,
     #[arg(global(true), value_hint = clap::ValueHint::Other, long, value_name = "N")]
     /// stage to build (indicates compiler to use/test, e.g., stage 0 uses the
     /// bootstrap compiler, stage 1 the stage 0 rustc artifacts, etc.)

src/bootstrap/src/lib.rs

@@ -1871,3 +1871,22 @@ pub fn generate_smart_stamp_hash(dir: &Path, additional_input: &str) -> String {
 
     hex::encode(hasher.finalize().as_slice())
 }
+
+/// Ensures that the behavior dump directory is properly initialized.
+pub fn prepare_behaviour_dump_dir(build: &Build) {
+    static INITIALIZED: OnceLock<bool> = OnceLock::new();
+
+    let dump_path = build.out.join("bootstrap-shims-dump");
+
+    let initialized = INITIALIZED.get().unwrap_or_else(|| &false);
+    if !initialized {
+        // clear old dumps
+        if dump_path.exists() {
+            t!(fs::remove_dir_all(&dump_path));
+        }
+
+        t!(fs::create_dir_all(&dump_path));
+
+        t!(INITIALIZED.set(true));
+    }
+}

src/bootstrap/src/utils/bin_helpers.rs

@@ -2,14 +2,18 @@
 //! dependency on the bootstrap library. This reduces the binary size and
 //! improves compilation time by reducing the linking time.
 
+use std::env;
+use std::fs::OpenOptions;
+use std::io::Write;
+use std::process::Command;
+use std::str::FromStr;
+
 /// Parses the value of the "RUSTC_VERBOSE" environment variable and returns it as a `usize`.
 /// If it was not defined, returns 0 by default.
 ///
 /// Panics if "RUSTC_VERBOSE" is defined with the value that is not an unsigned integer.
 pub(crate) fn parse_rustc_verbose() -> usize {
-    use std::str::FromStr;
-
-    match std::env::var("RUSTC_VERBOSE") {
+    match env::var("RUSTC_VERBOSE") {
         Ok(s) => usize::from_str(&s).expect("RUSTC_VERBOSE should be an integer"),
         Err(_) => 0,
     }
@@ -19,10 +23,29 @@ pub(crate) fn parse_rustc_verbose() -> usize {
 ///
 /// If "RUSTC_STAGE" was not set, the program will be terminated with 101.
 pub(crate) fn parse_rustc_stage() -> String {
-    std::env::var("RUSTC_STAGE").unwrap_or_else(|_| {
+    env::var("RUSTC_STAGE").unwrap_or_else(|_| {
         // Don't panic here; it's reasonable to try and run these shims directly. Give a helpful error instead.
         eprintln!("rustc shim: FATAL: RUSTC_STAGE was not set");
         eprintln!("rustc shim: NOTE: use `x.py build -vvv` to see all environment variables set by bootstrap");
         std::process::exit(101);
     })
 }
+
+/// Writes the command invocation to a file if `DUMP_BOOTSTRAP_SHIMS` is set during bootstrap.
+///
+/// Before writing it, replaces user-specific values to create generic dumps for cross-environment
+/// comparisons.
+pub(crate) fn maybe_dump(dump_name: String, cmd: &Command) {
+    if let Ok(dump_dir) = env::var("DUMP_BOOTSTRAP_SHIMS") {
+        let dump_file = format!("{dump_dir}/{dump_name}");
+
+        let mut file =
+            OpenOptions::new().create(true).write(true).append(true).open(&dump_file).unwrap();
+
+        let cmd_dump = format!("{:?}\n", cmd);
+        let cmd_dump = cmd_dump.replace(&env::var("BUILD_OUT").unwrap(), "${BUILD_OUT}");
+        let cmd_dump = cmd_dump.replace(&env::var("CARGO_HOME").unwrap(), "${CARGO_HOME}");
+
+        file.write_all(cmd_dump.as_bytes()).expect("Unable to write file");
+    }
+}

src/doc/rustc/src/linker-plugin-lto.md

@@ -136,14 +136,15 @@ able to get around this problem by setting `-Clinker=lld-link` in RUSTFLAGS
 ```python
 from collections import defaultdict
 import subprocess
+import sys
 
 def minor_version(version):
     return int(version.split('.')[1])
 
 INSTALL_TOOLCHAIN = ["rustup", "toolchain", "install", "--profile", "minimal"]
 subprocess.run(INSTALL_TOOLCHAIN + ["nightly"])
 
-LOWER_BOUND = 65
+LOWER_BOUND = 73
 NIGHTLY_VERSION = minor_version(subprocess.run(
     ["rustc", "+nightly", "--version"],
     capture_output=True,
@@ -159,6 +160,7 @@ def llvm_version(toolchain):
 version_map = defaultdict(lambda: [])
 for version in range(LOWER_BOUND, NIGHTLY_VERSION - 1):
     toolchain = "1.{}.0".format(version)
+    print("Checking", toolchain, file=sys.stderr)
     subprocess.run(
         INSTALL_TOOLCHAIN + ["--no-self-update", toolchain],
         capture_output=True)
@@ -196,6 +198,8 @@ The following table shows known good combinations of toolchain versions.
 | 1.52 - 1.55  |      12       |
 | 1.56 - 1.59  |      13       |
 | 1.60 - 1.64  |      14       |
-| 1.65         |      15       |
+| 1.65 - 1.69  |      15       |
+| 1.70 - 1.72  |      16       |
+| 1.73 - 1.74  |      17       |
 
 Note that the compatibility policy for this feature might change in the future.

src/doc/rustc/src/platform-support/TEMPLATE.md

@@ -6,7 +6,7 @@ One-sentence description of the target (e.g. CPU, OS)
 
 ## Target maintainers
 
-- Some Person, `[email protected]`, https://github.com/...
+- Some Person, https://github.com/...
 
 ## Requirements
 

src/doc/rustc/src/target-tier-policy.md

@@ -246,6 +246,8 @@ approved by the appropriate team for that shared code before acceptance.
     introducing unconditional uses of features that another variation of the
     target may not have; use conditional compilation or runtime detection, as
     appropriate, to let each target run code supported by that target.
+- Tier 3 targets must be able to produce assembly using at least one of
+  rustc's supported backends from any host target.
 
 If a tier 3 target stops meeting these requirements, or the target maintainers
 no longer have interest or time, or the target shows no signs of activity and