From 6e002317cec5fa0c55a88307f839f2b5fb31922c Mon Sep 17 00:00:00 2001 From: Maksim Bondarenkov Date: Sat, 19 Jul 2025 14:19:54 +0300 Subject: [PATCH] opt-dist: rebuild rustc when doing static LLVM builds when building LLVM it's obvious that in case of shared build rustc doesn't need to be recompiled, but with static builds it would be better to compile rustc again to ensure we linked proper library. maybe I didn't understand the pipeline correctly, but it was strange for me to see that in Stage 5 LLVM is built while rustc is not --- src/tools/opt-dist/src/exec.rs | 6 ++++++ src/tools/opt-dist/src/main.rs | 10 ++++++++-- 2 files changed, 14 insertions(+), 2 deletions(-) diff --git a/src/tools/opt-dist/src/exec.rs b/src/tools/opt-dist/src/exec.rs index 56eff2ca2a7df..e5a037dc4e9b2 100644 --- a/src/tools/opt-dist/src/exec.rs +++ b/src/tools/opt-dist/src/exec.rs @@ -189,6 +189,12 @@ impl Bootstrap { self } + /// Rebuild rustc in case of statically linked LLVM + pub fn rustc_rebuild(mut self) -> Self { + self.cmd = self.cmd.arg("--keep-stage").arg("0"); + self + } + pub fn run(self, timer: &mut TimerSection) -> anyhow::Result<()> { self.cmd.run()?; let metrics = load_metrics(&self.metrics_path)?; diff --git a/src/tools/opt-dist/src/main.rs b/src/tools/opt-dist/src/main.rs index 7857f196626bc..8dc7788361298 100644 --- a/src/tools/opt-dist/src/main.rs +++ b/src/tools/opt-dist/src/main.rs @@ -363,8 +363,14 @@ fn execute_pipeline( let mut dist = Bootstrap::dist(env, &dist_args) .llvm_pgo_optimize(llvm_pgo_profile.as_ref()) - .rustc_pgo_optimize(&rustc_pgo_profile) - .avoid_rustc_rebuild(); + .rustc_pgo_optimize(&rustc_pgo_profile); + + // if LLVM is not built we'll have PGO optimized rustc + dist = if env.supports_shared_llvm() || !env.build_llvm() { + dist.avoid_rustc_rebuild() + } else { + dist.rustc_rebuild() + }; for bolt_profile in bolt_profiles { dist = dist.with_bolt_profile(bolt_profile);