Merge ref '2a9bacf61876' from rust-lang/rust

Pull recent changes from https://github.com/rust-lang/rust via Josh.

Upstream ref: 2a9bacf6187685931d52346a0ecff2e52bdc91cc
Filtered ref: d7fc6d06166167894862d54c9618a3cd7599fa9c
Upstream diff: https://github.com/rust-lang/rust/compare/f4665ab8368ad2e8a86d4390ae35c28bdd9561bb...2a9bacf6187685931d52346a0ecff2e52bdc91cc

This merge was created using https://github.com/rust-lang/josh-sync.

2 files changed, 1 insertions, 935 deletions

diff --git a/library/std/src/sys/pal/unix/mod.rs b/library/std/src/sys/pal/unix/mod.rs
index ac5c823a1bf..dd1059fe04a 100644
--- a/library/std/src/sys/pal/unix/mod.rs
+++ b/library/std/src/sys/pal/unix/mod.rs
@@ -17,7 +17,6 @@ pub mod os;
 pub mod pipe;
 pub mod stack_overflow;
 pub mod sync;
-pub mod thread;
 pub mod thread_parking;
 pub mod time;
 
@@ -55,7 +54,7 @@ pub unsafe fn init(argc: isize, argv: *const *const u8, sigpipe: u8) {
     // thread-id for the main thread and so renaming the main thread will rename the
     // process and we only want to enable this on platforms we've tested.
     if cfg!(target_vendor = "apple") {
-        thread::Thread::set_name(&c"main");
+        crate::sys::thread::set_name(c"main");
     }
 
     unsafe fn sanitize_standard_fds() {
diff --git a/library/std/src/sys/pal/unix/thread.rs b/library/std/src/sys/pal/unix/thread.rs
deleted file mode 100644
index 3389b8c0c8a..00000000000
--- a/library/std/src/sys/pal/unix/thread.rs
+++ /dev/null
@@ -1,933 +0,0 @@
-use crate::ffi::CStr;
-use crate::mem::{self, ManuallyDrop};
-use crate::num::NonZero;
-#[cfg(all(target_os = "linux", target_env = "gnu"))]
-use crate::sys::weak::dlsym;
-#[cfg(any(target_os = "solaris", target_os = "illumos", target_os = "nto",))]
-use crate::sys::weak::weak;
-use crate::sys::{os, stack_overflow};
-use crate::time::{Duration, Instant};
-use crate::{cmp, io, ptr};
-#[cfg(not(any(
-    target_os = "l4re",
-    target_os = "vxworks",
-    target_os = "espidf",
-    target_os = "nuttx"
-)))]
-pub const DEFAULT_MIN_STACK_SIZE: usize = 2 * 1024 * 1024;
-#[cfg(target_os = "l4re")]
-pub const DEFAULT_MIN_STACK_SIZE: usize = 1024 * 1024;
-#[cfg(target_os = "vxworks")]
-pub const DEFAULT_MIN_STACK_SIZE: usize = 256 * 1024;
-#[cfg(any(target_os = "espidf", target_os = "nuttx"))]
-pub const DEFAULT_MIN_STACK_SIZE: usize = 0; // 0 indicates that the stack size configured in the ESP-IDF/NuttX menuconfig system should be used
-
-struct ThreadData {
-    name: Option<Box<str>>,
-    f: Box<dyn FnOnce()>,
-}
-
-pub struct Thread {
-    id: libc::pthread_t,
-}
-
-// Some platforms may have pthread_t as a pointer in which case we still want
-// a thread to be Send/Sync
-unsafe impl Send for Thread {}
-unsafe impl Sync for Thread {}
-
-impl Thread {
-    // unsafe: see thread::Builder::spawn_unchecked for safety requirements
-    #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
-    pub unsafe fn new(
-        stack: usize,
-        name: Option<&str>,
-        f: Box<dyn FnOnce()>,
-    ) -> io::Result<Thread> {
-        let data = Box::into_raw(Box::new(ThreadData { name: name.map(Box::from), f }));
-        let mut native: libc::pthread_t = mem::zeroed();
-        let mut attr: mem::MaybeUninit<libc::pthread_attr_t> = mem::MaybeUninit::uninit();
-        assert_eq!(libc::pthread_attr_init(attr.as_mut_ptr()), 0);
-
-        #[cfg(any(target_os = "espidf", target_os = "nuttx"))]
-        if stack > 0 {
-            // Only set the stack if a non-zero value is passed
-            // 0 is used as an indication that the default stack size configured in the ESP-IDF/NuttX menuconfig system should be used
-            assert_eq!(
-                libc::pthread_attr_setstacksize(
-                    attr.as_mut_ptr(),
-                    cmp::max(stack, min_stack_size(attr.as_ptr()))
-                ),
-                0
-            );
-        }
-
-        #[cfg(not(any(target_os = "espidf", target_os = "nuttx")))]
-        {
-            let stack_size = cmp::max(stack, min_stack_size(attr.as_ptr()));
-
-            match libc::pthread_attr_setstacksize(attr.as_mut_ptr(), stack_size) {
-                0 => {}
-                n => {
-                    assert_eq!(n, libc::EINVAL);
-                    // EINVAL means |stack_size| is either too small or not a
-                    // multiple of the system page size. Because it's definitely
-                    // >= PTHREAD_STACK_MIN, it must be an alignment issue.
-                    // Round up to the nearest page and try again.
-                    let page_size = os::page_size();
-                    let stack_size =
-                        (stack_size + page_size - 1) & (-(page_size as isize - 1) as usize - 1);
-
-                    // Some libc implementations, e.g. musl, place an upper bound
-                    // on the stack size, in which case we can only gracefully return
-                    // an error here.
-                    if libc::pthread_attr_setstacksize(attr.as_mut_ptr(), stack_size) != 0 {
-                        assert_eq!(libc::pthread_attr_destroy(attr.as_mut_ptr()), 0);
-                        drop(Box::from_raw(data));
-                        return Err(io::const_error!(
-                            io::ErrorKind::InvalidInput,
-                            "invalid stack size"
-                        ));
-                    }
-                }
-            };
-        }
-
-        let ret = libc::pthread_create(&mut native, attr.as_ptr(), thread_start, data as *mut _);
-        // Note: if the thread creation fails and this assert fails, then p will
-        // be leaked. However, an alternative design could cause double-free
-        // which is clearly worse.
-        assert_eq!(libc::pthread_attr_destroy(attr.as_mut_ptr()), 0);
-
-        return if ret != 0 {
-            // The thread failed to start and as a result p was not consumed. Therefore, it is
-            // safe to reconstruct the box so that it gets deallocated.
-            drop(Box::from_raw(data));
-            Err(io::Error::from_raw_os_error(ret))
-        } else {
-            Ok(Thread { id: native })
-        };
-
-        extern "C" fn thread_start(data: *mut libc::c_void) -> *mut libc::c_void {
-            unsafe {
-                let data = Box::from_raw(data as *mut ThreadData);
-                // Next, set up our stack overflow handler which may get triggered if we run
-                // out of stack.
-                let _handler = stack_overflow::Handler::new(data.name);
-                // Finally, let's run some code.
-                (data.f)();
-            }
-            ptr::null_mut()
-        }
-    }
-
-    pub fn yield_now() {
-        let ret = unsafe { libc::sched_yield() };
-        debug_assert_eq!(ret, 0);
-    }
-
-    #[cfg(target_os = "android")]
-    pub fn set_name(name: &CStr) {
-        const PR_SET_NAME: libc::c_int = 15;
-        unsafe {
-            let res = libc::prctl(
-                PR_SET_NAME,
-                name.as_ptr(),
-                0 as libc::c_ulong,
-                0 as libc::c_ulong,
-                0 as libc::c_ulong,
-            );
-            // We have no good way of propagating errors here, but in debug-builds let's check that this actually worked.
-            debug_assert_eq!(res, 0);
-        }
-    }
-
-    #[cfg(any(
-        target_os = "linux",
-        target_os = "freebsd",
-        target_os = "dragonfly",
-        target_os = "nuttx",
-        target_os = "cygwin"
-    ))]
-    pub fn set_name(name: &CStr) {
-        unsafe {
-            cfg_select! {
-                any(target_os = "linux", target_os = "cygwin") => {
-                    // Linux and Cygwin limits the allowed length of the name.
-                    const TASK_COMM_LEN: usize = 16;
-                    let name = truncate_cstr::<{ TASK_COMM_LEN }>(name);
-                }
-                _ => {
-                    // FreeBSD, DragonFly BSD and NuttX do not enforce length limits.
-                }
-            };
-            // Available since glibc 2.12, musl 1.1.16, and uClibc 1.0.20 for Linux,
-            // FreeBSD 12.2 and 13.0, and DragonFly BSD 6.0.
-            let res = libc::pthread_setname_np(libc::pthread_self(), name.as_ptr());
-            // We have no good way of propagating errors here, but in debug-builds let's check that this actually worked.
-            debug_assert_eq!(res, 0);
-        }
-    }
-
-    #[cfg(target_os = "openbsd")]
-    pub fn set_name(name: &CStr) {
-        unsafe {
-            libc::pthread_set_name_np(libc::pthread_self(), name.as_ptr());
-        }
-    }
-
-    #[cfg(target_vendor = "apple")]
-    pub fn set_name(name: &CStr) {
-        unsafe {
-            let name = truncate_cstr::<{ libc::MAXTHREADNAMESIZE }>(name);
-            let res = libc::pthread_setname_np(name.as_ptr());
-            // We have no good way of propagating errors here, but in debug-builds let's check that this actually worked.
-            debug_assert_eq!(res, 0);
-        }
-    }
-
-    #[cfg(target_os = "netbsd")]
-    pub fn set_name(name: &CStr) {
-        unsafe {
-            let res = libc::pthread_setname_np(
-                libc::pthread_self(),
-                c"%s".as_ptr(),
-                name.as_ptr() as *mut libc::c_void,
-            );
-            debug_assert_eq!(res, 0);
-        }
-    }
-
-    #[cfg(any(target_os = "solaris", target_os = "illumos", target_os = "nto"))]
-    pub fn set_name(name: &CStr) {
-        weak!(
-            fn pthread_setname_np(
-                thread: libc::pthread_t,
-                name: *const libc::c_char,
-            ) -> libc::c_int;
-        );
-
-        if let Some(f) = pthread_setname_np.get() {
-            #[cfg(target_os = "nto")]
-            const THREAD_NAME_MAX: usize = libc::_NTO_THREAD_NAME_MAX as usize;
-            #[cfg(any(target_os = "solaris", target_os = "illumos"))]
-            const THREAD_NAME_MAX: usize = 32;
-
-            let name = truncate_cstr::<{ THREAD_NAME_MAX }>(name);
-            let res = unsafe { f(libc::pthread_self(), name.as_ptr()) };
-            debug_assert_eq!(res, 0);
-        }
-    }
-
-    #[cfg(target_os = "fuchsia")]
-    pub fn set_name(name: &CStr) {
-        use super::fuchsia::*;
-        unsafe {
-            zx_object_set_property(
-                zx_thread_self(),
-                ZX_PROP_NAME,
-                name.as_ptr() as *const libc::c_void,
-                name.to_bytes().len(),
-            );
-        }
-    }
-
-    #[cfg(target_os = "haiku")]
-    pub fn set_name(name: &CStr) {
-        unsafe {
-            let thread_self = libc::find_thread(ptr::null_mut());
-            let res = libc::rename_thread(thread_self, name.as_ptr());
-            // We have no good way of propagating errors here, but in debug-builds let's check that this actually worked.
-            debug_assert_eq!(res, libc::B_OK);
-        }
-    }
-
-    #[cfg(target_os = "vxworks")]
-    pub fn set_name(name: &CStr) {
-        let mut name = truncate_cstr::<{ (libc::VX_TASK_RENAME_LENGTH - 1) as usize }>(name);
-        let res = unsafe { libc::taskNameSet(libc::taskIdSelf(), name.as_mut_ptr()) };
-        debug_assert_eq!(res, libc::OK);
-    }
-
-    #[cfg(any(
-        target_env = "newlib",
-        target_os = "l4re",
-        target_os = "emscripten",
-        target_os = "redox",
-        target_os = "hurd",
-        target_os = "aix",
-    ))]
-    pub fn set_name(_name: &CStr) {
-        // Newlib and Emscripten have no way to set a thread name.
-    }
-
-    #[cfg(not(target_os = "espidf"))]
-    pub fn sleep(dur: Duration) {
-        let mut secs = dur.as_secs();
-        let mut nsecs = dur.subsec_nanos() as _;
-
-        // If we're awoken with a signal then the return value will be -1 and
-        // nanosleep will fill in `ts` with the remaining time.
-        unsafe {
-            while secs > 0 || nsecs > 0 {
-                let mut ts = libc::timespec {
-                    tv_sec: cmp::min(libc::time_t::MAX as u64, secs) as libc::time_t,
-                    tv_nsec: nsecs,
-                };
-                secs -= ts.tv_sec as u64;
-                let ts_ptr = &raw mut ts;
-                if libc::nanosleep(ts_ptr, ts_ptr) == -1 {
-                    assert_eq!(os::errno(), libc::EINTR);
-                    secs += ts.tv_sec as u64;
-                    nsecs = ts.tv_nsec;
-                } else {
-                    nsecs = 0;
-                }
-            }
-        }
-    }
-
-    #[cfg(target_os = "espidf")]
-    pub fn sleep(dur: Duration) {
-        // ESP-IDF does not have `nanosleep`, so we use `usleep` instead.
-        // As per the documentation of `usleep`, it is expected to support
-        // sleep times as big as at least up to 1 second.
-        //
-        // ESP-IDF does support almost up to `u32::MAX`, but due to a potential integer overflow in its
-        // `usleep` implementation
-        // (https://github.com/espressif/esp-idf/blob/d7ca8b94c852052e3bc33292287ef4dd62c9eeb1/components/newlib/time.c#L210),
-        // we limit the sleep time to the maximum one that would not cause the underlying `usleep` implementation to overflow
-        // (`portTICK_PERIOD_MS` can be anything between 1 to 1000, and is 10 by default).
-        const MAX_MICROS: u32 = u32::MAX - 1_000_000 - 1;
-
-        // Add any nanoseconds smaller than a microsecond as an extra microsecond
-        // so as to comply with the `std::thread::sleep` contract which mandates
-        // implementations to sleep for _at least_ the provided `dur`.
-        // We can't overflow `micros` as it is a `u128`, while `Duration` is a pair of
-        // (`u64` secs, `u32` nanos), where the nanos are strictly smaller than 1 second
-        // (i.e. < 1_000_000_000)
-        let mut micros = dur.as_micros() + if dur.subsec_nanos() % 1_000 > 0 { 1 } else { 0 };
-
-        while micros > 0 {
-            let st = if micros > MAX_MICROS as u128 { MAX_MICROS } else { micros as u32 };
-            unsafe {
-                libc::usleep(st);
-            }
-
-            micros -= st as u128;
-        }
-    }
-
-    // Any unix that has clock_nanosleep
-    // If this list changes update the MIRI chock_nanosleep shim
-    #[cfg(any(
-        target_os = "freebsd",
-        target_os = "netbsd",
-        target_os = "linux",
-        target_os = "android",
-        target_os = "solaris",
-        target_os = "illumos",
-        target_os = "dragonfly",
-        target_os = "hurd",
-        target_os = "fuchsia",
-        target_os = "vxworks",
-    ))]
-    pub fn sleep_until(deadline: Instant) {
-        let Some(ts) = deadline.into_inner().into_timespec().to_timespec() else {
-            // The deadline is further in the future then can be passed to
-            // clock_nanosleep. We have to use Self::sleep instead. This might
-            // happen on 32 bit platforms, especially closer to 2038.
-            let now = Instant::now();
-            if let Some(delay) = deadline.checked_duration_since(now) {
-                Self::sleep(delay);
-            }
-            return;
-        };
-
-        unsafe {
-            // When we get interrupted (res = EINTR) call clock_nanosleep again
-            loop {
-                let res = libc::clock_nanosleep(
-                    super::time::Instant::CLOCK_ID,
-                    libc::TIMER_ABSTIME,
-                    &ts,
-                    core::ptr::null_mut(), // not required with TIMER_ABSTIME
-                );
-
-                if res == 0 {
-                    break;
-                } else {
-                    assert_eq!(
-                        res,
-                        libc::EINTR,
-                        "timespec is in range,
-                         clockid is valid and kernel should support it"
-                    );
-                }
-            }
-        }
-    }
-
-    // Any unix that does not have clock_nanosleep
-    #[cfg(not(any(
-        target_os = "freebsd",
-        target_os = "netbsd",
-        target_os = "linux",
-        target_os = "android",
-        target_os = "solaris",
-        target_os = "illumos",
-        target_os = "dragonfly",
-        target_os = "hurd",
-        target_os = "fuchsia",
-        target_os = "vxworks",
-    )))]
-    pub fn sleep_until(deadline: Instant) {
-        let now = Instant::now();
-        if let Some(delay) = deadline.checked_duration_since(now) {
-            Self::sleep(delay);
-        }
-    }
-
-    pub fn join(self) {
-        let id = self.into_id();
-        let ret = unsafe { libc::pthread_join(id, ptr::null_mut()) };
-        assert!(ret == 0, "failed to join thread: {}", io::Error::from_raw_os_error(ret));
-    }
-
-    pub fn id(&self) -> libc::pthread_t {
-        self.id
-    }
-
-    pub fn into_id(self) -> libc::pthread_t {
-        ManuallyDrop::new(self).id
-    }
-}
-
-impl Drop for Thread {
-    fn drop(&mut self) {
-        let ret = unsafe { libc::pthread_detach(self.id) };
-        debug_assert_eq!(ret, 0);
-    }
-}
-
-pub(crate) fn current_os_id() -> Option<u64> {
-    // Most Unix platforms have a way to query an integer ID of the current thread, all with
-    // slightly different spellings.
-    //
-    // The OS thread ID is used rather than `pthread_self` so as to match what will be displayed
-    // for process inspection (debuggers, trace, `top`, etc.).
-    cfg_select! {
-        // Most platforms have a function returning a `pid_t` or int, which is an `i32`.
-        any(target_os = "android", target_os = "linux") => {
-            use crate::sys::weak::syscall;
-
-            // `libc::gettid` is only available on glibc 2.30+, but the syscall is available
-            // since Linux 2.4.11.
-            syscall!(fn gettid() -> libc::pid_t;);
-
-            // SAFETY: FFI call with no preconditions.
-            let id: libc::pid_t = unsafe { gettid() };
-            Some(id as u64)
-        }
-        target_os = "nto" => {
-            // SAFETY: FFI call with no preconditions.
-            let id: libc::pid_t = unsafe { libc::gettid() };
-            Some(id as u64)
-        }
-        target_os = "openbsd" => {
-            // SAFETY: FFI call with no preconditions.
-            let id: libc::pid_t = unsafe { libc::getthrid() };
-            Some(id as u64)
-        }
-        target_os = "freebsd" => {
-            // SAFETY: FFI call with no preconditions.
-            let id: libc::c_int = unsafe { libc::pthread_getthreadid_np() };
-            Some(id as u64)
-        }
-        target_os = "netbsd" => {
-            // SAFETY: FFI call with no preconditions.
-            let id: libc::lwpid_t = unsafe { libc::_lwp_self() };
-            Some(id as u64)
-        }
-        any(target_os = "illumos", target_os = "solaris") => {
-            // On Illumos and Solaris, the `pthread_t` is the same as the OS thread ID.
-            // SAFETY: FFI call with no preconditions.
-            let id: libc::pthread_t = unsafe { libc::pthread_self() };
-            Some(id as u64)
-        }
-        target_vendor = "apple" => {
-            // Apple allows querying arbitrary thread IDs, `thread=NULL` queries the current thread.
-            let mut id = 0u64;
-            // SAFETY: `thread_id` is a valid pointer, no other preconditions.
-            let status: libc::c_int = unsafe { libc::pthread_threadid_np(0, &mut id) };
-            if status == 0 {
-                Some(id)
-            } else {
-                None
-            }
-        }
-        // Other platforms don't have an OS thread ID or don't have a way to access it.
-        _ => None,
-    }
-}
-
-#[cfg(any(
-    target_os = "linux",
-    target_os = "nto",
-    target_os = "solaris",
-    target_os = "illumos",
-    target_os = "vxworks",
-    target_os = "cygwin",
-    target_vendor = "apple",
-))]
-fn truncate_cstr<const MAX_WITH_NUL: usize>(cstr: &CStr) -> [libc::c_char; MAX_WITH_NUL] {
-    let mut result = [0; MAX_WITH_NUL];
-    for (src, dst) in cstr.to_bytes().iter().zip(&mut result[..MAX_WITH_NUL - 1]) {
-        *dst = *src as libc::c_char;
-    }
-    result
-}
-
-pub fn available_parallelism() -> io::Result<NonZero<usize>> {
-    cfg_select! {
-        any(
-            target_os = "android",
-            target_os = "emscripten",
-            target_os = "fuchsia",
-            target_os = "hurd",
-            target_os = "linux",
-            target_os = "aix",
-            target_vendor = "apple",
-            target_os = "cygwin",
-        ) => {
-            #[allow(unused_assignments)]
-            #[allow(unused_mut)]
-            let mut quota = usize::MAX;
-
-            #[cfg(any(target_os = "android", target_os = "linux"))]
-            {
-                quota = cgroups::quota().max(1);
-                let mut set: libc::cpu_set_t = unsafe { mem::zeroed() };
-                unsafe {
-                    if libc::sched_getaffinity(0, size_of::<libc::cpu_set_t>(), &mut set) == 0 {
-                        let count = libc::CPU_COUNT(&set) as usize;
-                        let count = count.min(quota);
-
-                        // According to sched_getaffinity's API it should always be non-zero, but
-                        // some old MIPS kernels were buggy and zero-initialized the mask if
-                        // none was explicitly set.
-                        // In that case we use the sysconf fallback.
-                        if let Some(count) = NonZero::new(count) {
-                            return Ok(count)
-                        }
-                    }
-                }
-            }
-            match unsafe { libc::sysconf(libc::_SC_NPROCESSORS_ONLN) } {
-                -1 => Err(io::Error::last_os_error()),
-                0 => Err(io::Error::UNKNOWN_THREAD_COUNT),
-                cpus => {
-                    let count = cpus as usize;
-                    // Cover the unusual situation where we were able to get the quota but not the affinity mask
-                    let count = count.min(quota);
-                    Ok(unsafe { NonZero::new_unchecked(count) })
-                }
-            }
-        }
-        any(
-           target_os = "freebsd",
-           target_os = "dragonfly",
-           target_os = "openbsd",
-           target_os = "netbsd",
-        ) => {
-            use crate::ptr;
-
-            #[cfg(target_os = "freebsd")]
-            {
-                let mut set: libc::cpuset_t = unsafe { mem::zeroed() };
-                unsafe {
-                    if libc::cpuset_getaffinity(
-                        libc::CPU_LEVEL_WHICH,
-                        libc::CPU_WHICH_PID,
-                        -1,
-                        size_of::<libc::cpuset_t>(),
-                        &mut set,
-                    ) == 0 {
-                        let count = libc::CPU_COUNT(&set) as usize;
-                        if count > 0 {
-                            return Ok(NonZero::new_unchecked(count));
-                        }
-                    }
-                }
-            }
-
-            #[cfg(target_os = "netbsd")]
-            {
-                unsafe {
-                    let set = libc::_cpuset_create();
-                    if !set.is_null() {
-                        let mut count: usize = 0;
-                        if libc::pthread_getaffinity_np(libc::pthread_self(), libc::_cpuset_size(set), set) == 0 {
-                            for i in 0..libc::cpuid_t::MAX {
-                                match libc::_cpuset_isset(i, set) {
-                                    -1 => break,
-                                    0 => continue,
-                                    _ => count = count + 1,
-                                }
-                            }
-                        }
-                        libc::_cpuset_destroy(set);
-                        if let Some(count) = NonZero::new(count) {
-                            return Ok(count);
-                        }
-                    }
-                }
-            }
-
-            let mut cpus: libc::c_uint = 0;
-            let mut cpus_size = size_of_val(&cpus);
-
-            unsafe {
-                cpus = libc::sysconf(libc::_SC_NPROCESSORS_ONLN) as libc::c_uint;
-            }
-
-            // Fallback approach in case of errors or no hardware threads.
-            if cpus < 1 {
-                let mut mib = [libc::CTL_HW, libc::HW_NCPU, 0, 0];
-                let res = unsafe {
-                    libc::sysctl(
-                        mib.as_mut_ptr(),
-                        2,
-                        (&raw mut cpus) as *mut _,
-                        (&raw mut cpus_size) as *mut _,
-                        ptr::null_mut(),
-                        0,
-                    )
-                };
-
-                // Handle errors if any.
-                if res == -1 {
-                    return Err(io::Error::last_os_error());
-                } else if cpus == 0 {
-                    return Err(io::Error::UNKNOWN_THREAD_COUNT);
-                }
-            }
-
-            Ok(unsafe { NonZero::new_unchecked(cpus as usize) })
-        }
-        target_os = "nto" => {
-            unsafe {
-                use libc::_syspage_ptr;
-                if _syspage_ptr.is_null() {
-                    Err(io::const_error!(io::ErrorKind::NotFound, "no syspage available"))
-                } else {
-                    let cpus = (*_syspage_ptr).num_cpu;
-                    NonZero::new(cpus as usize)
-                        .ok_or(io::Error::UNKNOWN_THREAD_COUNT)
-                }
-            }
-        }
-        any(target_os = "solaris", target_os = "illumos") => {
-            let mut cpus = 0u32;
-            if unsafe { libc::pset_info(libc::PS_MYID, core::ptr::null_mut(), &mut cpus, core::ptr::null_mut()) } != 0 {
-                return Err(io::Error::UNKNOWN_THREAD_COUNT);
-            }
-            Ok(unsafe { NonZero::new_unchecked(cpus as usize) })
-        }
-        target_os = "haiku" => {
-            // 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::UNKNOWN_THREAD_COUNT);
-                }
-
-                Ok(NonZero::new_unchecked(sinfo.cpu_count as usize))
-            }
-        }
-        target_os = "vxworks" => {
-            // Note: there is also `vxCpuConfiguredGet`, closer to _SC_NPROCESSORS_CONF
-            // expectations than the actual cores availability.
-            unsafe extern "C" {
-                fn vxCpuEnabledGet() -> libc::cpuset_t;
-            }
-
-            // SAFETY: `vxCpuEnabledGet` always fetches a mask with at least one bit set
-            unsafe{
-                let set = vxCpuEnabledGet();
-                Ok(NonZero::new_unchecked(set.count_ones() as usize))
-            }
-        }
-        _ => {
-            // FIXME: implement on Redox, l4re
-            Err(io::const_error!(io::ErrorKind::Unsupported, "getting the number of hardware threads is not supported on the target platform"))
-        }
-    }
-}
-
-#[cfg(any(target_os = "android", target_os = "linux"))]
-mod cgroups {
-    //! Currently not covered
-    //! * cgroup v2 in non-standard mountpoints
-    //! * paths containing control characters or spaces, since those would be escaped in procfs
-    //!   output and we don't unescape
-
-    use crate::borrow::Cow;
-    use crate::ffi::OsString;
-    use crate::fs::{File, exists};
-    use crate::io::{BufRead, Read};
-    use crate::os::unix::ffi::OsStringExt;
-    use crate::path::{Path, PathBuf};
-    use crate::str::from_utf8;
-
-    #[derive(PartialEq)]
-    enum Cgroup {
-        V1,
-        V2,
-    }
-
-    /// Returns cgroup CPU quota in core-equivalents, rounded down or usize::MAX if the quota cannot
-    /// be determined or is not set.
-    pub(super) fn quota() -> usize {
-        let mut quota = usize::MAX;
-        if cfg!(miri) {
-            // Attempting to open a file fails under default flags due to isolation.
-            // And Miri does not have parallelism anyway.
-            return quota;
-        }
-
-        let _: Option<()> = try {
-            let mut buf = Vec::with_capacity(128);
-            // find our place in the cgroup hierarchy
-            File::open("/proc/self/cgroup").ok()?.read_to_end(&mut buf).ok()?;
-            let (cgroup_path, version) =
-                buf.split(|&c| c == b'\n').fold(None, |previous, line| {
-                    let mut fields = line.splitn(3, |&c| c == b':');
-                    // 2nd field is a list of controllers for v1 or empty for v2
-                    let version = match fields.nth(1) {
-                        Some(b"") => Cgroup::V2,
-                        Some(controllers)
-                            if from_utf8(controllers)
-                                .is_ok_and(|c| c.split(',').any(|c| c == "cpu")) =>
-                        {
-                            Cgroup::V1
-                        }
-                        _ => return previous,
-                    };
-
-                    // already-found v1 trumps v2 since it explicitly specifies its controllers
-                    if previous.is_some() && version == Cgroup::V2 {
-                        return previous;
-                    }
-
-                    let path = fields.last()?;
-                    // skip leading slash
-                    Some((path[1..].to_owned(), version))
-                })?;
-            let cgroup_path = PathBuf::from(OsString::from_vec(cgroup_path));
-
-            quota = match version {
-                Cgroup::V1 => quota_v1(cgroup_path),
-                Cgroup::V2 => quota_v2(cgroup_path),
-            };
-        };
-
-        quota
-    }
-
-    fn quota_v2(group_path: PathBuf) -> usize {
-        let mut quota = usize::MAX;
-
-        let mut path = PathBuf::with_capacity(128);
-        let mut read_buf = String::with_capacity(20);
-
-        // standard mount location defined in file-hierarchy(7) manpage
-        let cgroup_mount = "/sys/fs/cgroup";
-
-        path.push(cgroup_mount);
-        path.push(&group_path);
-
-        path.push("cgroup.controllers");
-
-        // skip if we're not looking at cgroup2
-        if matches!(exists(&path), Err(_) | Ok(false)) {
-            return usize::MAX;
-        };
-
-        path.pop();
-
-        let _: Option<()> = try {
-            while path.starts_with(cgroup_mount) {
-                path.push("cpu.max");
-
-                read_buf.clear();
-
-                if File::open(&path).and_then(|mut f| f.read_to_string(&mut read_buf)).is_ok() {
-                    let raw_quota = read_buf.lines().next()?;
-                    let mut raw_quota = raw_quota.split(' ');
-                    let limit = raw_quota.next()?;
-                    let period = raw_quota.next()?;
-                    match (limit.parse::<usize>(), period.parse::<usize>()) {
-                        (Ok(limit), Ok(period)) if period > 0 => {
-                            quota = quota.min(limit / period);
-                        }
-                        _ => {}
-                    }
-                }
-
-                path.pop(); // pop filename
-                path.pop(); // pop dir
-            }
-        };
-
-        quota
-    }
-
-    fn quota_v1(group_path: PathBuf) -> usize {
-        let mut quota = usize::MAX;
-        let mut path = PathBuf::with_capacity(128);
-        let mut read_buf = String::with_capacity(20);
-
-        // Hardcode commonly used locations mentioned in the cgroups(7) manpage
-        // if that doesn't work scan mountinfo and adjust `group_path` for bind-mounts
-        let mounts: &[fn(&Path) -> Option<(_, &Path)>] = &[
-            |p| Some((Cow::Borrowed("/sys/fs/cgroup/cpu"), p)),
-            |p| Some((Cow::Borrowed("/sys/fs/cgroup/cpu,cpuacct"), p)),
-            // this can be expensive on systems with tons of mountpoints
-            // but we only get to this point when /proc/self/cgroups explicitly indicated
-            // this process belongs to a cpu-controller cgroup v1 and the defaults didn't work
-            find_mountpoint,
-        ];
-
-        for mount in mounts {
-            let Some((mount, group_path)) = mount(&group_path) else { continue };
-
-            path.clear();
-            path.push(mount.as_ref());
-            path.push(&group_path);
-
-            // skip if we guessed the mount incorrectly
-            if matches!(exists(&path), Err(_) | Ok(false)) {
-                continue;
-            }
-
-            while path.starts_with(mount.as_ref()) {
-                let mut parse_file = |name| {
-                    path.push(name);
-                    read_buf.clear();
-
-                    let f = File::open(&path);
-                    path.pop(); // restore buffer before any early returns
-                    f.ok()?.read_to_string(&mut read_buf).ok()?;
-                    let parsed = read_buf.trim().parse::<usize>().ok()?;
-
-                    Some(parsed)
-                };
-
-                let limit = parse_file("cpu.cfs_quota_us");
-                let period = parse_file("cpu.cfs_period_us");
-
-                match (limit, period) {
-                    (Some(limit), Some(period)) if period > 0 => quota = quota.min(limit / period),
-                    _ => {}
-                }
-
-                path.pop();
-            }
-
-            // we passed the try_exists above so we should have traversed the correct hierarchy
-            // when reaching this line
-            break;
-        }
-
-        quota
-    }
-
-    /// Scan mountinfo for cgroup v1 mountpoint with a cpu controller
-    ///
-    /// If the cgroupfs is a bind mount then `group_path` is adjusted to skip
-    /// over the already-included prefix
-    fn find_mountpoint(group_path: &Path) -> Option<(Cow<'static, str>, &Path)> {
-        let mut reader = File::open_buffered("/proc/self/mountinfo").ok()?;
-        let mut line = String::with_capacity(256);
-        loop {
-            line.clear();
-            if reader.read_line(&mut line).ok()? == 0 {
-                break;
-            }
-
-            let line = line.trim();
-            let mut items = line.split(' ');
-
-            let sub_path = items.nth(3)?;
-            let mount_point = items.next()?;
-            let mount_opts = items.next_back()?;
-            let filesystem_type = items.nth_back(1)?;
-
-            if filesystem_type != "cgroup" || !mount_opts.split(',').any(|opt| opt == "cpu") {
-                // not a cgroup / not a cpu-controller
-                continue;
-            }
-
-            let sub_path = Path::new(sub_path).strip_prefix("/").ok()?;
-
-            if !group_path.starts_with(sub_path) {
-                // this is a bind-mount and the bound subdirectory
-                // does not contain the cgroup this process belongs to
-                continue;
-            }
-
-            let trimmed_group_path = group_path.strip_prefix(sub_path).ok()?;
-
-            return Some((Cow::Owned(mount_point.to_owned()), trimmed_group_path));
-        }
-
-        None
-    }
-}
-
-// glibc >= 2.15 has a __pthread_get_minstack() function that returns
-// PTHREAD_STACK_MIN plus bytes needed for thread-local storage.
-// We need that information to avoid blowing up when a small stack
-// is created in an application with big thread-local storage requirements.
-// See #6233 for rationale and details.
-#[cfg(all(target_os = "linux", target_env = "gnu"))]
-unsafe fn min_stack_size(attr: *const libc::pthread_attr_t) -> usize {
-    // We use dlsym to avoid an ELF version dependency on GLIBC_PRIVATE. (#23628)
-    // We shouldn't really be using such an internal symbol, but there's currently
-    // no other way to account for the TLS size.
-    dlsym!(
-        fn __pthread_get_minstack(attr: *const libc::pthread_attr_t) -> libc::size_t;
-    );
-
-    match __pthread_get_minstack.get() {
-        None => libc::PTHREAD_STACK_MIN,
-        Some(f) => unsafe { f(attr) },
-    }
-}
-
-// No point in looking up __pthread_get_minstack() on non-glibc platforms.
-#[cfg(all(
-    not(all(target_os = "linux", target_env = "gnu")),
-    not(any(target_os = "netbsd", target_os = "nuttx"))
-))]
-unsafe fn min_stack_size(_: *const libc::pthread_attr_t) -> usize {
-    libc::PTHREAD_STACK_MIN
-}
-
-#[cfg(any(target_os = "netbsd", target_os = "nuttx"))]
-unsafe fn min_stack_size(_: *const libc::pthread_attr_t) -> usize {
-    static STACK: crate::sync::OnceLock<usize> = crate::sync::OnceLock::new();
-
-    *STACK.get_or_init(|| {
-        let mut stack = unsafe { libc::sysconf(libc::_SC_THREAD_STACK_MIN) };
-        if stack < 0 {
-            stack = 2048; // just a guess
-        }
-
-        stack as usize
-    })
-}