diff --git a/library/std/src/sys/unix/thread.rs b/library/std/src/sys/unix/thread.rs index 05f51a46168f6..5631834eca6fe 100644 --- a/library/std/src/sys/unix/thread.rs +++ b/library/std/src/sys/unix/thread.rs @@ -339,14 +339,18 @@ pub fn available_concurrency() -> io::Result { Ok(unsafe { NonZeroUsize::new_unchecked(cpus as usize) }) } else if #[cfg(target_os = "haiku")] { - let mut sinfo: libc::system_info = crate::mem::zeroed(); - let res = libc::get_system_info(&mut sinfo); + // system_info cpu_count field gets the static data set at boot time with `smp_set_num_cpus` + // `get_system_info` calls then `smp_get_num_cpus` + unsafe { + let mut sinfo: libc::system_info = crate::mem::zeroed(); + let res = libc::get_system_info(&mut sinfo); - if res != libc::B_OK { - return Err(io::Error::last_os_error()); - } + if res != libc::B_OK { + return Err(io::Error::new_const(io::ErrorKind::NotFound, &"The number of hardware threads is not known for the target platform")); + } - Ok(unsafe { NonZeroUsize::new_unchecked(sinfo.cpu_count as usize) }) + Ok(NonZeroUsize::new_unchecked(sinfo.cpu_count as usize)) + } } else { // FIXME: implement on vxWorks, Redox, l4re Err(io::Error::new_const(io::ErrorKind::Unsupported, &"Getting the number of hardware threads is not supported on the target platform"))