Auto merge of #141002 - GuillaumeGomez:subtree-update_cg_gcc_2025-05-14, r=GuillaumeGomez

Subtree update GCC backend 2025 05 14

cc `@antoyo`

Author: bors

compiler/rustc_codegen_gcc/.gitattributes

@@ -0,0 +1 @@
+Cargo.lock linguist-generated=false

compiler/rustc_codegen_gcc/.github/workflows/stdarch.yml

@@ -101,9 +101,8 @@ jobs:
       if: ${{ matrix.cargo_runner }}
       run: |
         # FIXME: these tests fail when the sysroot is compiled with LTO because of a missing symbol in proc-macro.
-        # TODO: remove --skip test_mm512_stream_ps when stdarch is updated in rustc.
         # TODO: remove --skip test_tile_ when it's implemented.
-        STDARCH_TEST_EVERYTHING=1 CHANNEL=release CARGO_TARGET_X86_64_UNKNOWN_LINUX_GNU_RUNNER="${{ matrix.cargo_runner }}" TARGET=x86_64-unknown-linux-gnu CG_RUSTFLAGS="-Ainternal_features --cfg stdarch_intel_sde" ./y.sh cargo test --manifest-path build/build_sysroot/sysroot_src/library/stdarch/Cargo.toml -- --skip rtm --skip tbm --skip sse4a --skip test_mm512_stream_ps --skip test_tile_
+        STDARCH_TEST_SKIP_FUNCTION="xsave,xsaveopt,xsave64,xsaveopt64" STDARCH_TEST_EVERYTHING=1 CHANNEL=release CARGO_TARGET_X86_64_UNKNOWN_LINUX_GNU_RUNNER="${{ matrix.cargo_runner }}" TARGET=x86_64-unknown-linux-gnu CG_RUSTFLAGS="-Ainternal_features" ./y.sh cargo test --manifest-path build/build_sysroot/sysroot_src/library/stdarch/Cargo.toml -- --skip rtm --skip tbm --skip sse4a --skip test_tile_
 
   # Summary job for the merge queue.
   # ALL THE PREVIOUS JOBS NEED TO BE ADDED TO THE `needs` SECTION OF THIS JOB!

compiler/rustc_codegen_gcc/CONTRIBUTING.md

@@ -0,0 +1,101 @@
+# Contributing to rustc_codegen_gcc
+
+Welcome to the `rustc_codegen_gcc` project! This guide will help you get started as a contributor. The project aims to provide a GCC codegen backend for rustc, allowing Rust compilation on platforms unsupported by LLVM and potentially improving runtime performance through GCC's optimizations.
+
+## Getting Started
+
+### Setting Up Your Development Environment
+
+For detailed setup instructions including dependencies, build steps, and initial testing, please refer to our [README](Readme.md). The README contains the most up-to-date information on:
+
+- Required dependencies and system packages
+- Repository setup and configuration
+- Build process
+- Basic test verification
+
+Once you've completed the setup process outlined in the README, you can proceed with the contributor-specific information below.
+
+## Communication Channels
+
+- Matrix: Join our [Matrix channel](https://matrix.to/#/#rustc_codegen_gcc:matrix.org)
+- IRC: Join us on [IRC](https://web.libera.chat/#rustc_codegen_gcc)
+- [GitHub Issues](https://github.com/rust-lang/rustc_codegen_gcc/issues): For bug reports and feature discussions
+
+We encourage new contributors to join our communication channels and introduce themselves. Feel free to ask questions about where to start or discuss potential contributions.
+
+## Understanding Core Concepts
+
+### Common Development Tasks
+
+#### Running Specific Tests
+
+To run specific tests, use appropriate flags such as:
+
+- `./y.sh test --test-libcore`
+- `./y.sh test --std-tests`
+- `cargo test -- <name of test>`
+
+Additionally, you can run the tests of `libgccjit`:
+
+```bash
+# libgccjit tests
+cd gcc-build/gcc
+make check-jit
+# For a specific test:
+make check-jit RUNTESTFLAGS="-v -v -v jit.exp=jit.dg/test-asm.cc"
+```
+
+#### Debugging Tools
+
+The project provides several environment variables for debugging:
+
+- `CG_GCCJIT_DUMP_GIMPLE`: Dumps the GIMPLE IR
+- `CG_RUSTFLAGS`: Additional Rust flags
+- `CG_GCCJIT_DUMP_MODULE`: Dumps a specific module
+- `CG_GCCJIT_DUMP_TO_FILE`: Creates C-like representation
+
+Full list of debugging options can be found in the [README](Readme.md#env-vars).
+
+## Making Contributions
+
+### Finding Issues to Work On
+
+1. Look for issues labeled with [`good first issue`](https://github.com/rust-lang/rustc_codegen_gcc/issues?q=is%3Aissue%20state%3Aopen%20label%3A"good%20first%20issue") or [`help wanted`](https://github.com/rust-lang/rustc_codegen_gcc/issues?q=is%3Aissue%20state%3Aopen%20label%3A"help%20wanted")
+2. Check the [progress report](https://blog.antoyo.xyz/rustc_codegen_gcc-progress-report-34#state_of_rustc_codegen_gcc) for larger initiatives
+3. Consider improving documentation or investigating [failing tests](https://github.com/rust-lang/rustc_codegen_gcc/tree/master/tests) (except `failing-ui-tests12.txt`)
+
+### Pull Request Process
+
+1. Fork the repository and create a new branch
+2. Make your changes with clear commit messages
+3. Add tests for new functionality
+4. Update documentation as needed
+5. Submit a PR with a description of your changes
+
+### Code Style Guidelines
+
+- Follow Rust standard coding conventions
+- Ensure your code passes `rustfmt` and `clippy`
+- Add comments explaining complex logic, especially in GCC interface code
+
+## Additional Resources
+
+- [Rustc Dev Guide](https://rustc-dev-guide.rust-lang.org/)
+- [GCC Internals Documentation](https://gcc.gnu.org/onlinedocs/gccint/)
+- Project-specific documentation in the `doc/` directory:
+  - [Common errors](doc/errors.md)
+  - [Debugging](doc/debugging.md)
+  - [Debugging libgccjit](doc/debugging-libgccjit.md)
+  - [Git subtree sync](doc/subtree.md)
+  - [List of useful commands](doc/tips.md)
+  - [Send a patch to GCC](doc/sending-gcc-patch.md)
+
+## Getting Help
+
+If you're stuck or unsure about anything:
+1. Check the existing documentation in the `doc/` directory
+2. Ask in the IRC or Matrix channels
+3. Open a GitHub issue for technical problems
+4. Comment on the issue you're working on if you need guidance
+
+Remember that all contributions, including documentation improvements, bug reports, and feature requests, are valuable to the project.

compiler/rustc_codegen_gcc/Cargo.lock

@@ -56,18 +56,18 @@ dependencies = [
 
 [[package]]
 name = "gccjit"
-version = "2.5.0"
+version = "2.7.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2895ddec764de7ac76fe6c056050c4801a80109c066f177a00a9cc8dee02b29b"
+checksum = "ae99a89184220d967dd300139f2d2ae7d52c1a69d632b24aacc57c54625254ce"
 dependencies = [
  "gccjit_sys",
 ]
 
 [[package]]
 name = "gccjit_sys"
-version = "0.6.0"
+version = "0.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ac133db68db8a6a8b2c51ef4b18d8ea16682d5814c4641272fe37bbbc223d5f3"
+checksum = "24edb7bfe2b7b27c6d09ed23eebfcab0b359c8fe978433f902943e6f127a0f1b"
 dependencies = [
  "libc",
 ]

compiler/rustc_codegen_gcc/Cargo.toml

@@ -2,7 +2,7 @@
 name = "rustc_codegen_gcc"
 version = "0.1.0"
 authors = ["Antoni Boucher <[email protected]>"]
-edition = "2018"
+edition = "2024"
 license = "MIT OR Apache-2.0"
 
 [lib]
@@ -22,7 +22,7 @@ master = ["gccjit/master"]
 default = ["master"]
 
 [dependencies]
-gccjit = "2.5"
+gccjit = "2.7"
 #gccjit = { git = "https://github.com/rust-lang/gccjit.rs" }
 
 # Local copy.

compiler/rustc_codegen_gcc/Readme.md

@@ -12,22 +12,38 @@ This is a GCC codegen for rustc, which means it can be loaded by the existing ru
 The primary goal of this project is to be able to compile Rust code on platforms unsupported by LLVM.
 A secondary goal is to check if using the gcc backend will provide any run-time speed improvement for the programs compiled using rustc.
 
-### Dependencies
-
-**rustup:** Follow the instructions on the official [website](https://www.rust-lang.org/tools/install)
-
-**DejaGnu:** Consider to install DejaGnu which is necessary for running the libgccjit test suite. [website](https://www.gnu.org/software/dejagnu/#downloading)
-
-
+## Getting Started
 
-## Building
-
-**This requires a patched libgccjit in order to work.
+Note: **This requires a patched libgccjit in order to work.
 You need to use my [fork of gcc](https://github.com/rust-lang/gcc) which already includes these patches.**
+The default configuration (see below in the [Quick start](#quick-start) section) will download a `libgccjit` built in the CI that already contains these patches, so you don't need to build this fork yourself if you use the default configuration.
 
-```bash
-$ cp config.example.toml config.toml
-```
+### Dependencies
+
+- rustup: follow instructions on the [official website](https://rustup.rs)
+- consider to install DejaGnu which is necessary for running the libgccjit test suite. [website](https://www.gnu.org/software/dejagnu/#downloading)
+- additional packages: `flex`, `libmpfr-dev`, `libgmp-dev`, `libmpc3`, `libmpc-dev`
+  
+### Quick start
+
+1. Clone and configure the repository:
+   ```bash
+   git clone https://github.com/rust-lang/rustc_codegen_gcc
+   cd rustc_codegen_gcc
+   cp config.example.toml config.toml
+   ```
+
+2. Build and test:
+   ```bash
+   ./y.sh prepare  # downloads and patches sysroot
+   ./y.sh build --sysroot --release
+   
+   # Verify setup with a simple test
+   ./y.sh cargo build --manifest-path tests/hello-world/Cargo.toml
+   
+   # Run full test suite (expect ~100 failing UI tests)
+   ./y.sh test --release
+   ```
 
 If don't need to test GCC patches you wrote in our GCC fork, then the default configuration should
 be all you need. You can update the `rustc_codegen_gcc` without worrying about GCC.
@@ -143,7 +159,7 @@ You can do the same manually (although we don't recommend it):
 $ LIBRARY_PATH="[gcc-path value]" LD_LIBRARY_PATH="[gcc-path value]" rustc +$(cat $CG_GCCJIT_DIR/rust-toolchain | grep 'channel' | cut -d '=' -f 2 | sed 's/"//g' | sed 's/ //g') -Cpanic=abort -Zcodegen-backend=$CG_GCCJIT_DIR/target/release/librustc_codegen_gcc.so --sysroot $CG_GCCJIT_DIR/build_sysroot/sysroot my_crate.rs
 ```
 
-## Env vars
+## Environment variables
 
  * _**CG_GCCJIT_DUMP_ALL_MODULES**_: Enables dumping of all compilation modules. When set to "1", a dump is created for each module during compilation and stored in `/tmp/reproducers/`.
  * _**CG_GCCJIT_DUMP_MODULE**_: Enables dumping of a specific module. When set with the module name, e.g., `CG_GCCJIT_DUMP_MODULE=module_name`, a dump of that specific module is created in `/tmp/reproducers/`.

compiler/rustc_codegen_gcc/build_system/Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 name = "y"
 version = "0.1.0"
-edition = "2021"
+edition = "2024"
 
 [dependencies]
 boml = "0.3.1"

compiler/rustc_codegen_gcc/build_system/src/main.rs

@@ -60,7 +60,9 @@ pub enum Command {
 
 fn main() {
     if env::var("RUST_BACKTRACE").is_err() {
-        env::set_var("RUST_BACKTRACE", "1");
+        unsafe {
+            env::set_var("RUST_BACKTRACE", "1");
+        }
     }
 
     let command = match env::args().nth(1).as_deref() {

compiler/rustc_codegen_gcc/build_system/src/utils.rs

@@ -10,7 +10,7 @@ use std::path::{Path, PathBuf};
 use std::process::{Command, ExitStatus, Output};
 
 #[cfg(unix)]
-extern "C" {
+unsafe extern "C" {
     fn raise(signal: c_int) -> c_int;
 }
 

compiler/rustc_codegen_gcc/example/mini_core.rs

@@ -1,6 +1,14 @@
 #![feature(
-    no_core, lang_items, intrinsics, unboxed_closures, extern_types,
-    decl_macro, rustc_attrs, transparent_unions, auto_traits, freeze_impls,
+    no_core,
+    lang_items,
+    intrinsics,
+    unboxed_closures,
+    extern_types,
+    decl_macro,
+    rustc_attrs,
+    transparent_unions,
+    auto_traits,
+    freeze_impls,
     thread_local
 )]
 #![no_core]
@@ -35,13 +43,13 @@ impl<T: ?Sized + Unsize<U>, U: ?Sized> CoerceUnsized<*mut U> for *mut T {}
 pub trait DispatchFromDyn<T> {}
 
 // &T -> &U
-impl<'a, T: ?Sized+Unsize<U>, U: ?Sized> DispatchFromDyn<&'a U> for &'a T {}
+impl<'a, T: ?Sized + Unsize<U>, U: ?Sized> DispatchFromDyn<&'a U> for &'a T {}
 // &mut T -> &mut U
-impl<'a, T: ?Sized+Unsize<U>, U: ?Sized> DispatchFromDyn<&'a mut U> for &'a mut T {}
+impl<'a, T: ?Sized + Unsize<U>, U: ?Sized> DispatchFromDyn<&'a mut U> for &'a mut T {}
 // *const T -> *const U
-impl<T: ?Sized+Unsize<U>, U: ?Sized> DispatchFromDyn<*const U> for *const T {}
+impl<T: ?Sized + Unsize<U>, U: ?Sized> DispatchFromDyn<*const U> for *const T {}
 // *mut T -> *mut U
-impl<T: ?Sized+Unsize<U>, U: ?Sized> DispatchFromDyn<*mut U> for *mut T {}
+impl<T: ?Sized + Unsize<U>, U: ?Sized> DispatchFromDyn<*mut U> for *mut T {}
 impl<T: ?Sized + Unsize<U>, U: ?Sized> DispatchFromDyn<Box<U, ()>> for Box<T, ()> {}
 
 #[lang = "legacy_receiver"]
@@ -52,8 +60,7 @@ impl<T: ?Sized> LegacyReceiver for &mut T {}
 impl<T: ?Sized, A: Allocator> LegacyReceiver for Box<T, A> {}
 
 #[lang = "receiver"]
-trait Receiver {
-}
+trait Receiver {}
 
 #[lang = "copy"]
 pub trait Copy {}
@@ -67,10 +74,13 @@ impl Copy for u16 {}
 impl Copy for u32 {}
 impl Copy for u64 {}
 impl Copy for usize {}
+impl Copy for u128 {}
 impl Copy for i8 {}
 impl Copy for i16 {}
 impl Copy for i32 {}
+impl Copy for i64 {}
 impl Copy for isize {}
+impl Copy for i128 {}
 impl Copy for f32 {}
 impl Copy for f64 {}
 impl Copy for char {}
@@ -336,7 +346,6 @@ impl PartialEq for u32 {
     }
 }
 
-
 impl PartialEq for u64 {
     fn eq(&self, other: &u64) -> bool {
         (*self) == (*other)
@@ -523,7 +532,11 @@ fn panic_in_cleanup() -> ! {
 #[track_caller]
 fn panic_bounds_check(index: usize, len: usize) -> ! {
     unsafe {
-        libc::printf("index out of bounds: the len is %d but the index is %d\n\0" as *const str as *const i8, len, index);
+        libc::printf(
+            "index out of bounds: the len is %d but the index is %d\n\0" as *const str as *const i8,
+            len,
+            index,
+        );
         intrinsics::abort();
     }
 }
@@ -551,8 +564,7 @@ pub trait Deref {
     fn deref(&self) -> &Self::Target;
 }
 
-pub trait Allocator {
-}
+pub trait Allocator {}
 
 impl Allocator for () {}
 
@@ -634,6 +646,8 @@ pub union MaybeUninit<T> {
 }
 
 pub mod intrinsics {
+    #[rustc_intrinsic]
+    pub const fn black_box<T>(_dummy: T) -> T;
     #[rustc_intrinsic]
     pub fn abort() -> !;
     #[rustc_intrinsic]
@@ -711,19 +725,27 @@ pub struct VaList<'a>(&'a mut VaListImpl);
 
 #[rustc_builtin_macro]
 #[rustc_macro_transparency = "semitransparent"]
-pub macro stringify($($t:tt)*) { /* compiler built-in */ }
+pub macro stringify($($t:tt)*) {
+    /* compiler built-in */
+}
 
 #[rustc_builtin_macro]
 #[rustc_macro_transparency = "semitransparent"]
-pub macro file() { /* compiler built-in */ }
+pub macro file() {
+    /* compiler built-in */
+}
 
 #[rustc_builtin_macro]
 #[rustc_macro_transparency = "semitransparent"]
-pub macro line() { /* compiler built-in */ }
+pub macro line() {
+    /* compiler built-in */
+}
 
 #[rustc_builtin_macro]
 #[rustc_macro_transparency = "semitransparent"]
-pub macro cfg() { /* compiler built-in */ }
+pub macro cfg() {
+    /* compiler built-in */
+}
 
 pub static A_STATIC: u8 = 42;
 

compiler/rustc_codegen_gcc/libgccjit.version

@@ -1 +1 @@
-0ea98a1365b81f7488073512c850e8ee951a4afd
+04ce66d8c918de9273bd7101638ad8724edf5e21

compiler/rustc_codegen_gcc/rust-toolchain

@@ -1,3 +1,3 @@
 [toolchain]
-channel = "nightly-2025-04-25"
+channel = "nightly-2025-05-12"
 components = ["rust-src", "rustc-dev", "llvm-tools-preview"]