add environ to unix

[LusterSourav]

see commit messages.

• libc-test/semver/unix.txt updated
• commit messages link to POSIX exec spec
• not applicable (no placeholder values)
• cargo test -p libc-test — 15 passed

Closes #2520

@rustbot label +stable-nominated

[LusterSourav]

[LusterSourav]

[LusterSourav]

https://man7.org/linux/man-pages/man7/environ.7.html

[LusterSourav]

https://man7.org/linux/man-pages/man7/feature_test_macros.7.html

[tgross35]

(updating status)

View changes since this review

[rustbot]

Reminder, once the PR becomes ready for a review, use @rustbot ready.

[rustbot]

⚠️ Warning ⚠️

• The following commits have merge commits (commits with multiple parents) in your changes. We have a no merge policy so these commits will need to be removed for this pull request to be merged.

  • bed3e32

  You can start a rebase with the following commands:

  $ # rebase
  $ git pull --rebase https://github.com/rust-lang/libc.git main
  $ git push --force-with-lease
  

[LusterSourav]

environ now linux-gnu only. glibc declares it in <unistd.h> behind _GNU_SOURCE. no ctest skips elsewhere. commit messages link to headers.

[LusterSourav]

@rustbot ready

[rustbot]

⚠️ Warning ⚠️

• The following commits have merge commits (commits with multiple parents) in your changes. We have a no merge policy so these commits will need to be removed for this pull request to be merged.

  • 9904a3b

  You can start a rebase with the following commands:

  $ # rebase
  $ git pull --rebase https://github.com/rust-lang/libc.git main
  $ git push --force-with-lease
  

[tgross35]

May as well take this but please clean up the history - 15 commits is a lot for a four line diff :)

@rustbot author

View changes since this review

[rustbot]

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.

[tgross35]

Please always include a link to headers in the commit message, the manpage is fine too but it's the headers we check against. I've already seen https://github.com/sailfishos-mirror/glibc/blob/4a07bb292f921c10e71fbf48c4a7f44391feb06c/posix/unistd.h#L566 though so this is okay.