From b42ff20c560fb53982b3f77d3fed5c459a01b545 Mon Sep 17 00:00:00 2001 From: jyn Date: Thu, 25 May 2023 23:56:15 -0500 Subject: [PATCH] Revert "Enable incremental independent of stage" This reverts commit 827f656ebb1230f31af6d968c4bfe69a79914ffc. Incremental is not sound to use across stages. Arbitrary changes to the compiler can invalidate the incremental cache - even changes to normal queries, not incremental itself! - and we do not currently enable `incremental-verify-ich` in bootstrap. Since 2018, we highly recommend and nudge users towards stage 1 builds instead of stage 2, and using `keep-stage` for anything other than libstd is very rare. I don't think the risk of unsoundness is worth the very minor speedup when building libstd. Disable incremental to avoid spurious panics and miscompilations when building with the stage 1 and 2 sysroot. --- src/bootstrap/builder.rs | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/src/bootstrap/builder.rs b/src/bootstrap/builder.rs index cf7c6596c0238..685824278ff25 100644 --- a/src/bootstrap/builder.rs +++ b/src/bootstrap/builder.rs @@ -1783,7 +1783,10 @@ impl<'a> Builder<'a> { cargo.env("RUSTC_TLS_MODEL_INITIAL_EXEC", "1"); } - if self.config.incremental { + // Ignore incremental modes except for stage0, since we're + // not guaranteeing correctness across builds if the compiler + // is changing under your feet. + if self.config.incremental && compiler.stage == 0 { cargo.env("CARGO_INCREMENTAL", "1"); } else { // Don't rely on any default setting for incr. comp. in Cargo