Start update to musl v1.2.3 by xbjfk · Pull Request #4443 · rust-lang/libc

xbjfk · 2025-05-03T13:42:15Z

Description

This is effectively a partial continuation of #3068 (no time64 yet), however done behind a flag so people can test changes in 0.2. Some changes are not behind the musl_v1_2_3 config flag, and these are:

The change to RLIM_NLIMITS. This one is definitely safe, as it has had a deprecation warning saying it could change any time with OS version for >5 years
The change to O_LARGEFILE is likely safe.
Same with the change to the tcp_info struct, as these only add fields while keeping ABI. However, if manually initializing all fields this could cause breakage.

Let me know if any of m assumptions are incorrect and I am happy to gate those changes behind the cfg as well.

I've also added #4437, as this seems like a good chance to rename the field while the cfg option is in place.

Sources

O_LARGEFILE change: https://github.com/bminor/musl/commit/b8b729bd22c28c9116c2fce65dce207a35299c26
RLIM_NLIMITS change: https://github.com/bminor/musl/commit/2507e7f5312e79620f6337935d0a6c9045ccba09
utmpx change: https://github.com/bminor/musl/commit/1e7f0fcd7ff2096904fd93a2ee6d12a2392be392
tcp_info changes: https://github.com/bminor/musl/commit/d4f298149c5e36ac5521888d645bfb65f4d027fc, https://github.com/bminor/musl/commit/5e0c9f246cf7c0d174b7b8fbd9e02d4729ff66d2

Checklist

(rest of) time64 API - this can be done in another PR after this one is merged
CPU_SETSIZE change (not urgent as changed after 1.2.3)
Relevant tests in libc-test/semver have been updated
No placeholder or unstable values like *LAST or *MAX are
included (see rust-lang/libc#3131)
Tested locally (cd libc-test && cargo test --target mytarget);
especially relevant for platforms that may not be checked in CI

@rustbot label +stable-nominated

xbjfk · 2025-05-03T13:45:42Z

hmm, looks like I need to allow deprecation for CI to pass - will allow deprecated tomorrow.

tgross35

Thank you for working on this! A handful of small comments, most importantly we don't want to stop testing the current musl version because that needs to continue working until we do the final version bump. Also looks like there is a CI failure.

src/unix/linux_like/linux/musl/b32/arm/mod.rs

libc-test/build.rs

ci/install-musl.sh

src/unix/linux_like/linux/musl/mod.rs

tgross35 · 2025-05-04T05:02:33Z

⚠️ Warning ⚠️

* There are issue links (such as `#123`) in the commit messages of the following commits.
  _Please remove them as they will spam the issue with references to the commit._
  
  * [5f03e36](https://github.com/rust-lang/libc/commit/5f03e36a51907a467127c9a722039842ff1fd066)

Disregard this, that's not a good warning

This was enabled in order to encourage canonical links. Unfortunately it seems to also create warnings for crosslinking issues [1], which is something we definitely do want contributors to do (especially considering how commits get cherry picked around in this repo, there may not be a PR to easily refer to). Disable `issue-links` for now to avoid this. This also means we lose canonical link warnings, but there wasn't really any specific reason we needed that anyway. Cc: rust-lang/triagebot#1965 [1]: rust-lang#4443 (comment)

ci/install-musl.sh

build.rs

src/unix/linux_like/linux/musl/mod.rs

tgross35 · 2025-05-05T02:48:26Z

This looks pretty good as a first step to me, I think we can merge it once you get CI passing.

@rustbot author

This reflects upstream commit 2507e7f. This should be safe to change as this has been marked deprecated to warn people it will change across OS versions since 0.2.64 (>5 years ago) (backport <rust-lang#4443>) (cherry picked from commit 5d24ad2)

This isn't strictly related to musl 1.2.3, however now presents a good time to change it, before the 1.0 release. (backport <rust-lang#4443>) (cherry picked from commit 3f81aad)

The architecture-specific definitions was removed in upstream commit 319b2d0, changing the type to the generic definition of int. (backport <rust-lang#4443>) (cherry picked from commit 3f91173)

This silences shellcheck warnings (backport <rust-lang#4443>) (cherry picked from commit 60f7b3d)

This will be chosen based on the RUST_LIBC_UNSTABLE_MUSL_V1_2_3 variable. Co-authored-by: Daniel Frampton <Daniel.Frampton@microsoft.com> (backport <rust-lang#4443>) (cherry picked from commit e7762a8)

This commit gates various workarounds of older musl versions behind the RUST_LIBC_UNSTABLE_MUSL_V1_2_3 variable. (backport <rust-lang#4443>) (cherry picked from commit 85a7c85)

This was accidentally set to 0 in upstream, but fixed in commit b8b729b. If running with prior versions without that commit, this commit effectively backports it. (backport <rust-lang#4443>) (cherry picked from commit 686aa7a)

This feature, controlled by the environment variable RUST_LIBC_UNSTABLE_MUSL_V1_2_3 will control whether breaking changes up to musl v1.2.3 will be reflected (backport <rust-lang#4443>) (cherry picked from commit 2a68f7f)

This ut_session has changed from long to int + padding in newer versions. This was already reflected on loongarch64 and ohos - this commit adds this change, and re-enables the test when musl_v1_2_3 is set. Co-authored-by: Ariadne Conill <ariadne@dereferenced.org> (backport <rust-lang#4443>) (cherry picked from commit 1038c7f)

This reflects the upstream commits, 5e0c9f2 and d4f2981, which reflect changes in linux 5.4 and 5.5 respectively As mentioned in the comments, this is possible now as the CI musl version has updated and the headers are newer. (backport <rust-lang#4443>) (cherry picked from commit fb4212a)