no method named `si_pid` found for struct `siginfo_t` for armv7-unknown-linux-uclibceabihf

[asomers]

I tried this code:

fn main() {
    println!("Hello, world!");
}

cargo check -Zbuild-std --target armv7-unknown-linux-uclibceabihf

I expected to see this happen: it should work

Instead, this happened: the build fails like this:

error[E0599]: no method named `si_pid` found for struct `siginfo_t` in the current scope
   --> /localhome/somers/.rustup/toolchains/nightly-x86_64-unknown-freebsd/lib/rustlib/src/rust/library/std/src/sys/unix/process/process_unix.rs:879:33
    |
879 |             if unsafe { siginfo.si_pid() } == 0 {
    |                                 ^^^^^^ method not found in `siginfo_t`

error[E0599]: no method named `si_status` found for struct `siginfo_t` in the current scope
   --> /localhome/somers/.rustup/toolchains/nightly-x86_64-unknown-freebsd/lib/rustlib/src/rust/library/std/src/sys/unix/process/process_unix.rs:917:39
    |
917 |         let status = unsafe { siginfo.si_status() };
    |                                       ^^^^^^^^^ method not found in `siginfo_t`

For more information about this error, try `rustc --explain E0599`.

Meta

rustc --version --verbose:

rustc 1.76.0-nightly (2f8d81f9d 2023-11-21)
binary: rustc
commit-hash: 2f8d81f9dbac6b8df982199f69da04a4c8357227
commit-date: 2023-11-21
host: x86_64-unknown-freebsd
release: 1.76.0-nightly
LLVM version: 17.0.5

[the8472]

I'm assuming that the linux kernel on that target still uses pretty much the same signal structure as most other ones so this is probably a libc issue that it lacks those accessors.

[asomers]

Probably, but it's a problem in the libc that's bundled with std, not the standalone crate. And since std itself doesn't compile, it's hard to bisect the standalone crate.

[the8472]

Bisecting shouldn't be needed, the uses in std were added in #117957.

[SteveLauC]

More context: nightly-2023-11-20 should be the first version of toolchain that is affected

[jieyouxu]

Hi, since rust-lang/libc#3529 is merged, is this still an issue?

[asomers]

@jieyouxu that only fixes the problem in the libc crate. libc is vendored within the standard library, so it's necessary to update the vendored version.

[jieyouxu]

@rustbot label +O-Arm +T-libs -needs-triage

[operutka]

@jieyouxu it's been merged into rust-lang/libc:main but the latest libc release 0.2.153 still does not contain it.