From bc6302ca6d452e54365bf7a724bf96beffd7280e Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Jakub=20Ber=C3=A1nek?= Date: Wed, 5 Mar 2025 11:38:05 +0100 Subject: [PATCH] Implement downloading GCC from CI --- src/bootstrap/src/core/build_steps/gcc.rs | 96 ++++++++++++++++++----- src/bootstrap/src/core/download.rs | 28 +++++++ 2 files changed, 104 insertions(+), 20 deletions(-) diff --git a/src/bootstrap/src/core/build_steps/gcc.rs b/src/bootstrap/src/core/build_steps/gcc.rs index 1382d5b07f91..7e1ec39659a3 100644 --- a/src/bootstrap/src/core/build_steps/gcc.rs +++ b/src/bootstrap/src/core/build_steps/gcc.rs @@ -13,10 +13,11 @@ use std::path::{Path, PathBuf}; use std::sync::OnceLock; use build_helper::ci::CiEnv; +use build_helper::git::get_closest_merge_commit; use crate::Config; use crate::core::builder::{Builder, Cargo, Kind, RunConfig, ShouldRun, Step}; -use crate::core::config::TargetSelection; +use crate::core::config::{GccCiMode, TargetSelection}; use crate::utils::build_stamp::{BuildStamp, generate_smart_stamp_hash}; use crate::utils::exec::command; use crate::utils::helpers::{self, t}; @@ -89,17 +90,39 @@ pub enum GccBuildStatus { ShouldBuild(Meta), } -/// This returns whether we've already previously built GCC. +/// Tries to download GCC from CI if it is enabled and GCC artifacts +/// are available for the given target. +/// Returns a path to the libgccjit.so file. +fn try_download_gcc(builder: &Builder<'_>, target: TargetSelection) -> Option { + // Try to download GCC from CI if configured and available + if !matches!(builder.config.gcc_ci_mode, GccCiMode::DownloadFromCi) { + return None; + } + if target != "x86_64-unknown-linux-gnu" { + eprintln!("GCC CI download is only available for the `x86_64-unknown-linux-gnu` target"); + return None; + } + let sha = + detect_gcc_sha(&builder.config, builder.config.rust_info.is_managed_git_subrepository()); + let root = ci_gcc_root(&builder.config); + let gcc_stamp = BuildStamp::new(&root).with_prefix("gcc").add_stamp(&sha); + if !gcc_stamp.is_up_to_date() && !builder.config.dry_run() { + builder.config.download_ci_gcc(&sha, &root); + t!(gcc_stamp.write()); + } + // FIXME: put libgccjit.so into a lib directory in dist::Gcc + Some(root.join("libgccjit.so")) +} + +/// This returns information about whether GCC should be built or if it's already built. +/// It transparently handles downloading GCC from CI if needed. /// /// It's used to avoid busting caches during x.py check -- if we've already built /// GCC, it's fine for us to not try to avoid doing so. pub fn get_gcc_build_status(builder: &Builder<'_>, target: TargetSelection) -> GccBuildStatus { - // Initialize the gcc submodule if not initialized already. - builder.config.update_submodule("src/gcc"); - - let root = builder.src.join("src/gcc"); - let out_dir = builder.gcc_out(target).join("build"); - let install_dir = builder.gcc_out(target).join("install"); + if let Some(path) = try_download_gcc(builder, target) { + return GccBuildStatus::AlreadyBuilt(path); + } static STAMP_HASH_MEMO: OnceLock = OnceLock::new(); let smart_stamp_hash = STAMP_HASH_MEMO.get_or_init(|| { @@ -110,6 +133,13 @@ pub fn get_gcc_build_status(builder: &Builder<'_>, target: TargetSelection) -> G ) }); + // Initialize the gcc submodule if not initialized already. + builder.config.update_submodule("src/gcc"); + + let root = builder.src.join("src/gcc"); + let out_dir = builder.gcc_out(target).join("build"); + let install_dir = builder.gcc_out(target).join("install"); + let stamp = BuildStamp::new(&out_dir).with_prefix("gcc").add_stamp(smart_stamp_hash); if stamp.is_up_to_date() { @@ -142,7 +172,7 @@ fn libgccjit_built_path(install_dir: &Path) -> PathBuf { install_dir.join("lib/libgccjit.so") } -fn build_gcc(metadata: &Meta, builder: &Builder, target: TargetSelection) { +fn build_gcc(metadata: &Meta, builder: &Builder<'_>, target: TargetSelection) { let Meta { stamp: _, out_dir, install_dir, root } = metadata; t!(fs::create_dir_all(out_dir)); @@ -202,17 +232,12 @@ fn build_gcc(metadata: &Meta, builder: &Builder, target: TargetSelection) { } configure_cmd.run(builder); - command("make") - .current_dir(&out_dir) - .arg("--silent") - .arg(format!("-j{}", builder.jobs())) - .run_capture_stdout(builder); - command("make") - .current_dir(&out_dir) - .arg("--silent") - .arg("install") - .run_capture_stdout(builder); - } + command("make") + .current_dir(out_dir) + .arg("--silent") + .arg(format!("-j{}", builder.jobs())) + .run_capture_stdout(builder); + command("make").current_dir(out_dir).arg("--silent").arg("install").run_capture_stdout(builder); } /// Configures a Cargo invocation so that it can build the GCC codegen backend. @@ -220,3 +245,34 @@ pub fn add_cg_gcc_cargo_flags(cargo: &mut Cargo, gcc: &GccOutput) { // Add the path to libgccjit.so to the linker search paths. cargo.rustflag(&format!("-L{}", gcc.libgccjit.parent().unwrap().to_str().unwrap())); } + +/// The absolute path to the downloaded GCC artifacts. +fn ci_gcc_root(config: &Config) -> PathBuf { + config.out.join(config.build).join("ci-gcc") +} + +/// This retrieves the GCC sha we *want* to use, according to git history. +fn detect_gcc_sha(config: &Config, is_git: bool) -> String { + let gcc_sha = if is_git { + get_closest_merge_commit( + Some(&config.src), + &config.git_config(), + &[config.src.join("src/gcc"), config.src.join("src/bootstrap/download-ci-gcc-stamp")], + ) + .unwrap() + } else if let Some(info) = crate::utils::channel::read_commit_info_file(&config.src) { + info.sha.trim().to_owned() + } else { + "".to_owned() + }; + + if gcc_sha.is_empty() { + eprintln!("error: could not find commit hash for downloading GCC"); + eprintln!("HELP: maybe your repository history is too shallow?"); + eprintln!("HELP: consider disabling `download-ci-gcc`"); + eprintln!("HELP: or fetch enough history to include one upstream commit"); + panic!(); + } + + gcc_sha +} diff --git a/src/bootstrap/src/core/download.rs b/src/bootstrap/src/core/download.rs index c477bdb829a9..95feb41ffd0c 100644 --- a/src/bootstrap/src/core/download.rs +++ b/src/bootstrap/src/core/download.rs @@ -826,6 +826,34 @@ download-rustc = false let llvm_root = self.ci_llvm_root(); self.unpack(&tarball, &llvm_root, "rust-dev"); } + + pub fn download_ci_gcc(&self, gcc_sha: &str, root_dir: &Path) { + let cache_prefix = format!("gcc-{gcc_sha}"); + let cache_dst = + self.bootstrap_cache_path.as_ref().cloned().unwrap_or_else(|| self.out.join("cache")); + + let gcc_cache = cache_dst.join(cache_prefix); + if !gcc_cache.exists() { + t!(fs::create_dir_all(&gcc_cache)); + } + let base = &self.stage0_metadata.config.artifacts_server; + let filename = format!("gcc-nightly-{}.tar.xz", self.build.triple); + let tarball = gcc_cache.join(&filename); + if !tarball.exists() { + let help_on_error = "ERROR: failed to download gcc from ci + + HELP: There could be two reasons behind this: + 1) The host triple is not supported for `download-ci-gcc`. + 2) Old builds get deleted after a certain time. + HELP: In either case, disable `download-ci-gcc` in your config.toml: + + [gcc] + download-ci-gcc = false + "; + self.download_file(&format!("{base}/{gcc_sha}/{filename}"), &tarball, help_on_error); + } + self.unpack(&tarball, root_dir, "gcc"); + } } fn path_is_dylib(path: &Path) -> bool {