test: Set version-dependent skips based on header defines by tgross35 · Pull Request #5188 · rust-lang/libc

tgross35 · 2026-06-21T09:45:19Z

When there are additions or updates that are only available with newer
platform versions, we don't have a great way to handle testing. The only
thing we can really do is unconditionally skip anything that doesn't
pass on the oldest versions we have on CI.

Improve this by adding a preprocess-only compiler invocation that
collects versions from the headers we are building against. These are
then used to skip

This initial patch only uses the versions for skips on Linux and
replacing the NetBSD uname invocation.

Also included is an IO number fix that showed up in the new tests.

tgross35 · 2026-06-23T07:38:38Z

I think this is pretty reasonable, and probably the easiest way to make sure anyone on a different kernel version than CI doesn't get a handful of errors, but could use a second set of eyes.

Thomasdezeeuw · 2026-06-26T08:40:04Z

+
+#[derive(Clone, Copy, Debug, Default)]
+struct Versions {
+    linux: Option<(u32, u32)>,


Does it make sense to remove the Option here and make (0, 0) the current None, that would make the comparison in the code easier to deal with.

View changes since the review

I did it this way is to make it more obvious when there's a version detection failure so we can figure it out and fix it, rather than silently falling back and skipping more than needed. But I forgot to actually make use of this, updated now to unwrap rather than default for Linux.

When there are additions or updates that are only available with newer platform versions, we don't have a great way to handle testing. The only thing we can really do is unconditionally skip anything that doesn't pass on the oldest versions we have on CI. Improve this by adding a preprocess-only compiler invocation that collects versions from the headers we are building against. These are then used to skip This initial patch only uses the versions for skips on Linux and replacing the NetBSD `uname` invocation.

PowerPC, Sparc, and MIPS (32- and 64-bit for all) have different `_IOC` numbers, meaning the constants were inaccurate. Example error on PowerPC64: bad `EPIOCSPARAMS` value at byte 4: rust: 64 (0x40) != c 128 (0x80) rust bytes: 00 00 00 00 40 08 8a 01 c bytes: 00 00 00 00 80 08 8a 01 bad `EPIOCGPARAMS` value at byte 4: rust: 128 (0x80) != c 64 (0x40) rust bytes: 00 00 00 00 80 08 8a 02 c bytes: 00 00 00 00 40 08 8a 02 Resolve this by using `_IOW` and `_IOR`. Source: https://github.com/torvalds/linux/blob/502d801f0ab03e4f32f9a33d203154ce84887921/include/uapi/linux/eventpoll.h#L97-L99 Fixes: fb58c01 ("epoll: add busy polling parameters")

rustbot · 2026-06-26T09:11:18Z

This PR was rebased onto a different main commit. Here's a range-diff highlighting what actually changed.

Rebasing is a normal part of keeping PRs up to date, so no action is needed—this note is just to help reviewers.

JohnTitor

The concept makes sense to me 👍

View changes since this review

When there are additions or updates that are only available with newer platform versions, we don't have a great way to handle testing. The only thing we can really do is unconditionally skip anything that doesn't pass on the oldest versions we have on CI. Improve this by adding a preprocess-only compiler invocation that collects versions from the headers we are building against. These are then used to skip This initial patch only uses the versions for skips on Linux and replacing the NetBSD `uname` invocation. (backport <rust-lang#5188>) (cherry picked from commit ccadc03)

PowerPC, Sparc, and MIPS (32- and 64-bit for all) have different `_IOC` numbers, meaning the constants were inaccurate. Example error on PowerPC64: bad `EPIOCSPARAMS` value at byte 4: rust: 64 (0x40) != c 128 (0x80) rust bytes: 00 00 00 00 40 08 8a 01 c bytes: 00 00 00 00 80 08 8a 01 bad `EPIOCGPARAMS` value at byte 4: rust: 128 (0x80) != c 64 (0x40) rust bytes: 00 00 00 00 80 08 8a 02 c bytes: 00 00 00 00 40 08 8a 02 Resolve this by using `_IOW` and `_IOR`. Source: https://github.com/torvalds/linux/blob/502d801f0ab03e4f32f9a33d203154ce84887921/include/uapi/linux/eventpoll.h#L97-L99 Fixes: fb58c01 ("epoll: add busy polling parameters") (backport <rust-lang#5188>) (cherry picked from commit 73f264c)

When there are additions or updates that are only available with newer platform versions, we don't have a great way to handle testing. The only thing we can really do is unconditionally skip anything that doesn't pass on the oldest versions we have on CI. Improve this by adding a preprocess-only compiler invocation that collects versions from the headers we are building against. These are then used to skip This initial patch only uses the versions for skips on Linux and replacing the NetBSD `uname` invocation. (backport <rust-lang#5188>) (cherry picked from commit ccadc03)

PowerPC, Sparc, and MIPS (32- and 64-bit for all) have different `_IOC` numbers, meaning the constants were inaccurate. Example error on PowerPC64: bad `EPIOCSPARAMS` value at byte 4: rust: 64 (0x40) != c 128 (0x80) rust bytes: 00 00 00 00 40 08 8a 01 c bytes: 00 00 00 00 80 08 8a 01 bad `EPIOCGPARAMS` value at byte 4: rust: 128 (0x80) != c 64 (0x40) rust bytes: 00 00 00 00 80 08 8a 02 c bytes: 00 00 00 00 40 08 8a 02 Resolve this by using `_IOW` and `_IOR`. Source: https://github.com/torvalds/linux/blob/502d801f0ab03e4f32f9a33d203154ce84887921/include/uapi/linux/eventpoll.h#L97-L99 Fixes: fb58c01 ("epoll: add busy polling parameters") (backport <rust-lang#5188>) (cherry picked from commit 73f264c)

When there are additions or updates that are only available with newer platform versions, we don't have a great way to handle testing. The only thing we can really do is unconditionally skip anything that doesn't pass on the oldest versions we have on CI. Improve this by adding a preprocess-only compiler invocation that collects versions from the headers we are building against. These are then used to skip This initial patch only uses the versions for skips on Linux and replacing the NetBSD `uname` invocation. (backport <rust-lang#5188>) (cherry picked from commit ccadc03)

PowerPC, Sparc, and MIPS (32- and 64-bit for all) have different `_IOC` numbers, meaning the constants were inaccurate. Example error on PowerPC64: bad `EPIOCSPARAMS` value at byte 4: rust: 64 (0x40) != c 128 (0x80) rust bytes: 00 00 00 00 40 08 8a 01 c bytes: 00 00 00 00 80 08 8a 01 bad `EPIOCGPARAMS` value at byte 4: rust: 128 (0x80) != c 64 (0x40) rust bytes: 00 00 00 00 80 08 8a 02 c bytes: 00 00 00 00 40 08 8a 02 Resolve this by using `_IOW` and `_IOR`. Source: https://github.com/torvalds/linux/blob/502d801f0ab03e4f32f9a33d203154ce84887921/include/uapi/linux/eventpoll.h#L97-L99 Fixes: fb58c01 ("epoll: add busy polling parameters") (backport <rust-lang#5188>) (cherry picked from commit 73f264c)

tgross35 force-pushed the version-skips branch 7 times, most recently from 76aae41 to 0636284 Compare June 22, 2026 09:30

rustbot added the A-CI Area: CI-related items label Jun 22, 2026

tgross35 force-pushed the version-skips branch 9 times, most recently from 8af7d0a to 69fa8db Compare June 23, 2026 07:12

tgross35 changed the title ~~test: Only skip new additions on older kernels~~ test: Set version-dependent skips based on header defines Jun 23, 2026

tgross35 force-pushed the version-skips branch 2 times, most recently from 16a376c to 44cb2ca Compare June 23, 2026 07:33

tgross35 marked this pull request as ready for review June 23, 2026 07:35

rustbot added the S-waiting-on-review label Jun 23, 2026

tgross35 requested a review from JohnTitor June 23, 2026 07:35

tgross35 mentioned this pull request Jun 23, 2026

Dragonfly fixes #5116

Merged

3 tasks

tgross35 force-pushed the version-skips branch from 44cb2ca to 8827fab Compare June 23, 2026 23:13

This comment has been minimized.

Sign in to view

tgross35 force-pushed the version-skips branch from 8827fab to 96e5a09 Compare June 24, 2026 07:34

This comment has been minimized.

Sign in to view

tgross35 mentioned this pull request Jun 26, 2026

Add additional fields to statx #4621

Merged

3 tasks

Thomasdezeeuw reviewed Jun 26, 2026

View reviewed changes

tgross35 added 2 commits June 26, 2026 05:11

tgross35 force-pushed the version-skips branch from 0005805 to 515564d Compare June 26, 2026 09:11

JohnTitor approved these changes Jun 28, 2026

View reviewed changes

tgross35 enabled auto-merge June 28, 2026 20:30

tgross35 added this pull request to the merge queue Jun 28, 2026

Merged via the queue into rust-lang:main with commit 73f264c Jun 28, 2026
80 of 107 checks passed

rustbot removed the S-waiting-on-review label Jun 28, 2026

tgross35 deleted the version-skips branch June 29, 2026 18:55

tgross35 added the stable-nominated This PR should be considered for cherry-pick to libc's stable release branch label Jun 29, 2026

This was referenced Jul 20, 2026

[0.2] Backports #5293

Merged

[0.2] Backports #5294

Merged

tgross35 added stable-applied This PR has been cherry-picked to libc's stable release branch and removed stable-nominated This PR should be considered for cherry-pick to libc's stable release branch labels Jul 21, 2026

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Uh oh!

test: Set version-dependent skips based on header defines#5188

test: Set version-dependent skips based on header defines#5188
tgross35 merged 2 commits into
rust-lang:mainfrom
tgross35:version-skips

tgross35 commented Jun 21, 2026 •

edited

Loading

Uh oh!

tgross35 commented Jun 23, 2026

Uh oh!

This comment has been minimized.

This comment has been minimized.

This comment has been minimized.

This comment has been minimized.

Thomasdezeeuw Jun 26, 2026 •

edited by rustbot

Loading

Uh oh!

tgross35 Jun 26, 2026

Uh oh!

rustbot commented Jun 26, 2026

Uh oh!

JohnTitor left a comment •

edited by rustbot

Loading

Uh oh!

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

4 participants

Uh oh!

Conversation

tgross35 commented Jun 21, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

tgross35 commented Jun 23, 2026

Uh oh!

This comment has been minimized.

This comment has been minimized.

This comment has been minimized.

This comment has been minimized.

Thomasdezeeuw Jun 26, 2026 • edited by rustbot Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Choose a reason for hiding this comment

Uh oh!

tgross35 Jun 26, 2026

Choose a reason for hiding this comment

Uh oh!

rustbot commented Jun 26, 2026

Uh oh!

JohnTitor left a comment • edited by rustbot Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

4 participants

tgross35 commented Jun 21, 2026 •

edited

Loading

Thomasdezeeuw Jun 26, 2026 •

edited by rustbot

Loading

JohnTitor left a comment •

edited by rustbot

Loading