Move bootstrap configuration to library workspace #149514
Open
+86
−61
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This uses a build probe to figure out the current toolchain version - the only alternative to this is bespoke logic in Cargo to tell `test` when the toolchain is stable/unstable. The behaviour should be the same as when using `CFG_DISABLE_UNSTABLE_FEATURES` unless an arbitrary channel is provided to bootstrap, which I believe necessitates a fork anyway.
rustbot
added
A-CI
Collaborator
|
rustbot has assigned @Mark-Simulacrum. Use |
rustbot
added
T-bootstrap
bjorn3
reviewed
Dec 2, 2025
| } else { | ||
| match (mode, self.config.rust_optimize.is_release()) { | ||
| // Some std configuration exists in its own profile | ||
| (Mode::Std, true) => Some("dist"), |
Member
There was a problem hiding this comment.
The -Cembed-bitcode=yes has to also be enabled when the standard library is compiled without optimizations. Otherwise the resulting toolchain is unable to do LTO.
bjorn3
reviewed
Dec 2, 2025
| [profile.dist] | ||
| inherits = "release" | ||
| codegen-units = 1 | ||
| debug = 1 # "limited" |
Member
There was a problem hiding this comment.
Doesn't this get unconditionally overridden by the value set for debuginfo-level-std?
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
4 participants
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
This creates a new "dist" profile in the standard library which contains configuration for the distributed std artifacts previously contained in bootstrap, in order for a future build-std implementation to use. bootstrap.toml settings continue to override these defaults, as would any RUSTFLAGS provided. I've left some cargo features driven by bootstrap for a future patch.
Unfortunately, profiles aren't expressive enough to express per-target overrides, so this risc-v example was not able to be moved across. This could go in its own profile which Cargo would have to know to use, and then the panic-abort rustflags overrides would need duplicating again. Doesn't seem like a sustainable solution as a couple similar overrides would explode the number of lines here.
We could use a cargo config in the library workspace for this, but this then would have to be respected by Cargo's build-std implementation and I'm not yet sure about the tradeoffs there.
This patch also introduces a build probe to deal with the test crate's stability which is obviously not ideal, I'm open to other solutions here or can back that change out for now if anyone prefers.
cc @Mark-Simulacrum rust-lang/rfcs#3874