Merging upstream version 1.69.0+dfsg1.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

37 files changed, 1155 insertions, 699 deletions

diff --git a/library/std/src/sys/common/alloc.rs b/library/std/src/sys/common/alloc.rs
index 3edbe7280..403a5e627 100644
--- a/library/std/src/sys/common/alloc.rs
+++ b/library/std/src/sys/common/alloc.rs
@@ -7,6 +7,7 @@ use crate::ptr;
 #[cfg(any(
     target_arch = "x86",
     target_arch = "arm",
+    target_arch = "m68k",
     target_arch = "mips",
     target_arch = "powerpc",
     target_arch = "powerpc64",
diff --git a/library/std/src/sys/hermit/args.rs b/library/std/src/sys/hermit/args.rs
index afcae6c90..220a76e4b 100644
--- a/library/std/src/sys/hermit/args.rs
+++ b/library/std/src/sys/hermit/args.rs
@@ -1,6 +1,6 @@
 use crate::ffi::{c_char, CStr, OsString};
 use crate::fmt;
-use crate::os::unix::ffi::OsStringExt;
+use crate::os::hermit::ffi::OsStringExt;
 use crate::ptr;
 use crate::sync::atomic::{
     AtomicIsize, AtomicPtr,
diff --git a/library/std/src/sys/hermit/fd.rs b/library/std/src/sys/hermit/fd.rs
index c400f5f2c..3a2cdd301 100644
--- a/library/std/src/sys/hermit/fd.rs
+++ b/library/std/src/sys/hermit/fd.rs
@@ -1,36 +1,23 @@
 #![unstable(reason = "not public", issue = "none", feature = "fd")]
 
 use crate::io::{self, Read};
-use crate::mem;
+use crate::os::hermit::io::{FromRawFd, OwnedFd, RawFd};
 use crate::sys::cvt;
 use crate::sys::hermit::abi;
 use crate::sys::unsupported;
-use crate::sys_common::AsInner;
+use crate::sys_common::{AsInner, FromInner, IntoInner};
+
+use crate::os::hermit::io::*;
 
 #[derive(Debug)]
 pub struct FileDesc {
-    fd: i32,
+    fd: OwnedFd,
 }
 
 impl FileDesc {
-    pub fn new(fd: i32) -> FileDesc {
-        FileDesc { fd }
-    }
-
-    pub fn raw(&self) -> i32 {
-        self.fd
-    }
-
-    /// Extracts the actual file descriptor without closing it.
-    pub fn into_raw(self) -> i32 {
-        let fd = self.fd;
-        mem::forget(self);
-        fd
-    }
-
     pub fn read(&self, buf: &mut [u8]) -> io::Result<usize> {
-        let result = unsafe { abi::read(self.fd, buf.as_mut_ptr(), buf.len()) };
-        cvt(result as i32)
+        let result = cvt(unsafe { abi::read(self.fd.as_raw_fd(), buf.as_mut_ptr(), buf.len()) })?;
+        Ok(result as usize)
     }
 
     pub fn read_to_end(&self, buf: &mut Vec<u8>) -> io::Result<usize> {
@@ -39,8 +26,8 @@ impl FileDesc {
     }
 
     pub fn write(&self, buf: &[u8]) -> io::Result<usize> {
-        let result = unsafe { abi::write(self.fd, buf.as_ptr(), buf.len()) };
-        cvt(result as i32)
+        let result = cvt(unsafe { abi::write(self.fd.as_raw_fd(), buf.as_ptr(), buf.len()) })?;
+        Ok(result as usize)
     }
 
     pub fn duplicate(&self) -> io::Result<FileDesc> {
@@ -69,19 +56,45 @@ impl<'a> Read for &'a FileDesc {
     }
 }
 
-impl AsInner<i32> for FileDesc {
-    fn as_inner(&self) -> &i32 {
+impl IntoInner<OwnedFd> for FileDesc {
+    fn into_inner(self) -> OwnedFd {
+        self.fd
+    }
+}
+
+impl FromInner<OwnedFd> for FileDesc {
+    fn from_inner(owned_fd: OwnedFd) -> Self {
+        Self { fd: owned_fd }
+    }
+}
+
+impl FromRawFd for FileDesc {
+    unsafe fn from_raw_fd(raw_fd: RawFd) -> Self {
+        Self { fd: FromRawFd::from_raw_fd(raw_fd) }
+    }
+}
+
+impl AsInner<OwnedFd> for FileDesc {
+    fn as_inner(&self) -> &OwnedFd {
         &self.fd
     }
 }
 
-impl Drop for FileDesc {
-    fn drop(&mut self) {
-        // Note that errors are ignored when closing a file descriptor. The
-        // reason for this is that if an error occurs we don't actually know if
-        // the file descriptor was closed or not, and if we retried (for
-        // something like EINTR), we might close another valid file descriptor
-        // (opened after we closed ours.
-        let _ = unsafe { abi::close(self.fd) };
+impl AsFd for FileDesc {
+    fn as_fd(&self) -> BorrowedFd<'_> {
+        self.fd.as_fd()
+    }
+}
+
+impl AsRawFd for FileDesc {
+    #[inline]
+    fn as_raw_fd(&self) -> RawFd {
+        self.fd.as_raw_fd()
+    }
+}
+
+impl IntoRawFd for FileDesc {
+    fn into_raw_fd(self) -> RawFd {
+        self.fd.into_raw_fd()
     }
 }
diff --git a/library/std/src/sys/hermit/fs.rs b/library/std/src/sys/hermit/fs.rs
index 6fb92c037..c966f2177 100644
--- a/library/std/src/sys/hermit/fs.rs
+++ b/library/std/src/sys/hermit/fs.rs
@@ -3,14 +3,17 @@ use crate::fmt;
 use crate::hash::{Hash, Hasher};
 use crate::io::{self, Error, ErrorKind};
 use crate::io::{BorrowedCursor, IoSlice, IoSliceMut, SeekFrom};
+use crate::os::hermit::io::{AsFd, AsRawFd, BorrowedFd, FromRawFd, IntoRawFd, RawFd};
 use crate::path::{Path, PathBuf};
 use crate::sys::common::small_c_string::run_path_with_cstr;
 use crate::sys::cvt;
-use crate::sys::hermit::abi;
-use crate::sys::hermit::abi::{O_APPEND, O_CREAT, O_EXCL, O_RDONLY, O_RDWR, O_TRUNC, O_WRONLY};
+use crate::sys::hermit::abi::{
+    self, O_APPEND, O_CREAT, O_EXCL, O_RDONLY, O_RDWR, O_TRUNC, O_WRONLY,
+};
 use crate::sys::hermit::fd::FileDesc;
 use crate::sys::time::SystemTime;
 use crate::sys::unsupported;
+use crate::sys_common::{AsInner, AsInnerMut, FromInner, IntoInner};
 
 pub use crate::sys_common::fs::{copy, try_exists};
 //pub use crate::sys_common::fs::remove_dir_all;
@@ -283,7 +286,7 @@ impl File {
         }
 
         let fd = unsafe { cvt(abi::open(path.as_ptr(), flags, mode))? };
-        Ok(File(FileDesc::new(fd as i32)))
+        Ok(File(unsafe { FileDesc::from_raw_fd(fd as i32) }))
     }
 
     pub fn file_attr(&self) -> io::Result<FileAttr> {
@@ -363,6 +366,54 @@ impl DirBuilder {
     }
 }
 
+impl AsInner<FileDesc> for File {
+    fn as_inner(&self) -> &FileDesc {
+        &self.0
+    }
+}
+
+impl AsInnerMut<FileDesc> for File {
+    fn as_inner_mut(&mut self) -> &mut FileDesc {
+        &mut self.0
+    }
+}
+
+impl IntoInner<FileDesc> for File {
+    fn into_inner(self) -> FileDesc {
+        self.0
+    }
+}
+
+impl FromInner<FileDesc> for File {
+    fn from_inner(file_desc: FileDesc) -> Self {
+        Self(file_desc)
+    }
+}
+
+impl AsFd for File {
+    fn as_fd(&self) -> BorrowedFd<'_> {
+        self.0.as_fd()
+    }
+}
+
+impl AsRawFd for File {
+    fn as_raw_fd(&self) -> RawFd {
+        self.0.as_raw_fd()
+    }
+}
+
+impl IntoRawFd for File {
+    fn into_raw_fd(self) -> RawFd {
+        self.0.into_raw_fd()
+    }
+}
+
+impl FromRawFd for File {
+    unsafe fn from_raw_fd(raw_fd: RawFd) -> Self {
+        Self(FromRawFd::from_raw_fd(raw_fd))
+    }
+}
+
 pub fn readdir(_p: &Path) -> io::Result<ReadDir> {
     unsupported()
 }
diff --git a/library/std/src/sys/hermit/mod.rs b/library/std/src/sys/hermit/mod.rs
index 6811fadb0..d34a4cfed 100644
--- a/library/std/src/sys/hermit/mod.rs
+++ b/library/std/src/sys/hermit/mod.rs
@@ -13,7 +13,7 @@
 //! compiling for wasm. That way it's a compile time error for something that's
 //! guaranteed to be a runtime error!
 
-#![allow(unsafe_op_in_unsafe_fn)]
+#![allow(missing_docs, nonstandard_style, unsafe_op_in_unsafe_fn)]
 
 use crate::intrinsics;
 use crate::os::raw::c_char;
@@ -57,9 +57,7 @@ pub mod locks {
 }
 
 use crate::io::ErrorKind;
-
-#[allow(unused_extern_crates)]
-pub extern crate hermit_abi as abi;
+use crate::os::hermit::abi;
 
 pub fn unsupported<T>() -> crate::io::Result<T> {
     Err(unsupported_err())
@@ -72,11 +70,6 @@ pub fn unsupported_err() -> crate::io::Error {
     )
 }
 
-#[no_mangle]
-pub extern "C" fn floor(x: f64) -> f64 {
-    unsafe { intrinsics::floorf64(x) }
-}
-
 pub fn abort_internal() -> ! {
     unsafe {
         abi::abort();
@@ -131,25 +124,72 @@ pub unsafe extern "C" fn runtime_entry(
 
 pub fn decode_error_kind(errno: i32) -> ErrorKind {
     match errno {
-        x if x == 13 as i32 => ErrorKind::PermissionDenied,
-        x if x == 98 as i32 => ErrorKind::AddrInUse,
-        x if x == 99 as i32 => ErrorKind::AddrNotAvailable,
-        x if x == 11 as i32 => ErrorKind::WouldBlock,
-        x if x == 103 as i32 => ErrorKind::ConnectionAborted,
-        x if x == 111 as i32 => ErrorKind::ConnectionRefused,
-        x if x == 104 as i32 => ErrorKind::ConnectionReset,
-        x if x == 17 as i32 => ErrorKind::AlreadyExists,
-        x if x == 4 as i32 => ErrorKind::Interrupted,
-        x if x == 22 as i32 => ErrorKind::InvalidInput,
-        x if x == 2 as i32 => ErrorKind::NotFound,
-        x if x == 107 as i32 => ErrorKind::NotConnected,
-        x if x == 1 as i32 => ErrorKind::PermissionDenied,
-        x if x == 32 as i32 => ErrorKind::BrokenPipe,
-        x if x == 110 as i32 => ErrorKind::TimedOut,
+        abi::errno::EACCES => ErrorKind::PermissionDenied,
+        abi::errno::EADDRINUSE => ErrorKind::AddrInUse,
+        abi::errno::EADDRNOTAVAIL => ErrorKind::AddrNotAvailable,
+        abi::errno::EAGAIN => ErrorKind::WouldBlock,
+        abi::errno::ECONNABORTED => ErrorKind::ConnectionAborted,
+        abi::errno::ECONNREFUSED => ErrorKind::ConnectionRefused,
+        abi::errno::ECONNRESET => ErrorKind::ConnectionReset,
+        abi::errno::EEXIST => ErrorKind::AlreadyExists,
+        abi::errno::EINTR => ErrorKind::Interrupted,
+        abi::errno::EINVAL => ErrorKind::InvalidInput,
+        abi::errno::ENOENT => ErrorKind::NotFound,
+        abi::errno::ENOTCONN => ErrorKind::NotConnected,
+        abi::errno::EPERM => ErrorKind::PermissionDenied,
+        abi::errno::EPIPE => ErrorKind::BrokenPipe,
+        abi::errno::ETIMEDOUT => ErrorKind::TimedOut,
         _ => ErrorKind::Uncategorized,
     }
 }
 
-pub fn cvt(result: i32) -> crate::io::Result<usize> {
-    if result < 0 { Err(crate::io::Error::from_raw_os_error(-result)) } else { Ok(result as usize) }
+#[doc(hidden)]
+pub trait IsNegative {
+    fn is_negative(&self) -> bool;
+    fn negate(&self) -> i32;
+}
+
+macro_rules! impl_is_negative {
+    ($($t:ident)*) => ($(impl IsNegative for $t {
+        fn is_negative(&self) -> bool {
+            *self < 0
+        }
+
+        fn negate(&self) -> i32 {
+            i32::try_from(-(*self)).unwrap()
+        }
+    })*)
+}
+
+impl IsNegative for i32 {
+    fn is_negative(&self) -> bool {
+        *self < 0
+    }
+
+    fn negate(&self) -> i32 {
+        -(*self)
+    }
+}
+impl_is_negative! { i8 i16 i64 isize }
+
+pub fn cvt<T: IsNegative>(t: T) -> crate::io::Result<T> {
+    if t.is_negative() {
+        let e = decode_error_kind(t.negate());
+        Err(crate::io::Error::from(e))
+    } else {
+        Ok(t)
+    }
+}
+
+pub fn cvt_r<T, F>(mut f: F) -> crate::io::Result<T>
+where
+    T: IsNegative,
+    F: FnMut() -> T,
+{
+    loop {
+        match cvt(f()) {
+            Err(ref e) if e.kind() == ErrorKind::Interrupted => {}
+            other => return other,
+        }
+    }
 }
diff --git a/library/std/src/sys/hermit/net.rs b/library/std/src/sys/hermit/net.rs
index 8a13879d8..5fb6281aa 100644
--- a/library/std/src/sys/hermit/net.rs
+++ b/library/std/src/sys/hermit/net.rs
@@ -1,490 +1,353 @@
-use crate::fmt;
-use crate::io::{self, ErrorKind, IoSlice, IoSliceMut};
-use crate::net::{IpAddr, Ipv4Addr, Ipv6Addr, Shutdown, SocketAddr};
-use crate::str;
-use crate::sync::Arc;
-use crate::sys::hermit::abi;
-use crate::sys::hermit::abi::IpAddress::{Ipv4, Ipv6};
-use crate::sys::unsupported;
-use crate::sys_common::AsInner;
+#![allow(dead_code)]
+
+use crate::cmp;
+use crate::io::{self, IoSlice, IoSliceMut};
+use crate::mem;
+use crate::net::{Shutdown, SocketAddr};
+use crate::os::hermit::io::{AsFd, AsRawFd, BorrowedFd, FromRawFd, RawFd};
+use crate::sys::hermit::fd::FileDesc;
+use crate::sys::time::Instant;
+use crate::sys_common::net::{getsockopt, setsockopt, sockaddr_to_addr};
+use crate::sys_common::{AsInner, FromInner, IntoInner};
 use crate::time::Duration;
 
-/// Checks whether the HermitCore's socket interface has been started already, and
-/// if not, starts it.
-pub fn init() -> io::Result<()> {
-    if abi::network_init() < 0 {
-        return Err(io::const_io_error!(
-            ErrorKind::Uncategorized,
-            "Unable to initialize network interface",
-        ));
-    }
-
-    Ok(())
-}
-
-#[derive(Debug, Clone)]
-pub struct Socket(abi::Handle);
-
-impl AsInner<abi::Handle> for Socket {
-    fn as_inner(&self) -> &abi::Handle {
-        &self.0
-    }
-}
+use core::ffi::c_int;
 
-impl Drop for Socket {
-    fn drop(&mut self) {
-        let _ = abi::tcpstream::close(self.0);
-    }
-}
+#[allow(unused_extern_crates)]
+pub extern crate hermit_abi as netc;
 
-// Arc is used to count the number of used sockets.
-// Only if all sockets are released, the drop
-// method will close the socket.
-#[derive(Clone)]
-pub struct TcpStream(Arc<Socket>);
-
-impl TcpStream {
-    pub fn connect(addr: io::Result<&SocketAddr>) -> io::Result<TcpStream> {
-        let addr = addr?;
-
-        match abi::tcpstream::connect(addr.ip().to_string().as_bytes(), addr.port(), None) {
-            Ok(handle) => Ok(TcpStream(Arc::new(Socket(handle)))),
-            _ => Err(io::const_io_error!(
-                ErrorKind::Uncategorized,
-                "Unable to initiate a connection on a socket",
-            )),
-        }
-    }
+pub use crate::sys::{cvt, cvt_r};
 
-    pub fn connect_timeout(saddr: &SocketAddr, duration: Duration) -> io::Result<TcpStream> {
-        match abi::tcpstream::connect(
-            saddr.ip().to_string().as_bytes(),
-            saddr.port(),
-            Some(duration.as_millis() as u64),
-        ) {
-            Ok(handle) => Ok(TcpStream(Arc::new(Socket(handle)))),
-            _ => Err(io::const_io_error!(
-                ErrorKind::Uncategorized,
-                "Unable to initiate a connection on a socket",
-            )),
-        }
-    }
+pub type wrlen_t = usize;
 
-    pub fn set_read_timeout(&self, duration: Option<Duration>) -> io::Result<()> {
-        abi::tcpstream::set_read_timeout(*self.0.as_inner(), duration.map(|d| d.as_millis() as u64))
-            .map_err(|_| {
-                io::const_io_error!(ErrorKind::Uncategorized, "Unable to set timeout value")
-            })
+pub fn cvt_gai(err: i32) -> io::Result<()> {
+    if err == 0 {
+        return Ok(());
     }
 
-    pub fn set_write_timeout(&self, duration: Option<Duration>) -> io::Result<()> {
-        abi::tcpstream::set_write_timeout(
-            *self.0.as_inner(),
-            duration.map(|d| d.as_millis() as u64),
-        )
-        .map_err(|_| io::const_io_error!(ErrorKind::Uncategorized, "Unable to set timeout value"))
-    }
+    let detail = "";
 
-    pub fn read_timeout(&self) -> io::Result<Option<Duration>> {
-        let duration = abi::tcpstream::get_read_timeout(*self.0.as_inner()).map_err(|_| {
-            io::const_io_error!(ErrorKind::Uncategorized, "Unable to determine timeout value")
-        })?;
+    Err(io::Error::new(
+        io::ErrorKind::Uncategorized,
+        &format!("failed to lookup address information: {detail}")[..],
+    ))
+}
 
-        Ok(duration.map(|d| Duration::from_millis(d)))
+/// Checks whether the HermitCore's socket interface has been started already, and
+/// if not, starts it.
+pub fn init() {
+    if unsafe { netc::network_init() } < 0 {
+        panic!("Unable to initialize network interface");
     }
+}
 
-    pub fn write_timeout(&self) -> io::Result<Option<Duration>> {
-        let duration = abi::tcpstream::get_write_timeout(*self.0.as_inner()).map_err(|_| {
-            io::const_io_error!(ErrorKind::Uncategorized, "Unable to determine timeout value")
-        })?;
+#[derive(Debug)]
+pub struct Socket(FileDesc);
 
-        Ok(duration.map(|d| Duration::from_millis(d)))
+impl Socket {
+    pub fn new(addr: &SocketAddr, ty: i32) -> io::Result<Socket> {
+        let fam = match *addr {
+            SocketAddr::V4(..) => netc::AF_INET,
+            SocketAddr::V6(..) => netc::AF_INET6,
+        };
+        Socket::new_raw(fam, ty)
     }
 
-    pub fn peek(&self, buf: &mut [u8]) -> io::Result<usize> {
-        abi::tcpstream::peek(*self.0.as_inner(), buf)
-            .map_err(|_| io::const_io_error!(ErrorKind::Uncategorized, "peek failed"))
+    pub fn new_raw(fam: i32, ty: i32) -> io::Result<Socket> {
+        let fd = cvt(unsafe { netc::socket(fam, ty, 0) })?;
+        Ok(Socket(unsafe { FileDesc::from_raw_fd(fd) }))
     }
 
-    pub fn read(&self, buffer: &mut [u8]) -> io::Result<usize> {
-        self.read_vectored(&mut [IoSliceMut::new(buffer)])
+    pub fn new_pair(_fam: i32, _ty: i32) -> io::Result<(Socket, Socket)> {
+        unimplemented!()
     }
 
-    pub fn read_vectored(&self, ioslice: &mut [IoSliceMut<'_>]) -> io::Result<usize> {
-        let mut size: usize = 0;
-
-        for i in ioslice.iter_mut() {
-            let ret = abi::tcpstream::read(*self.0.as_inner(), &mut i[0..]).map_err(|_| {
-                io::const_io_error!(ErrorKind::Uncategorized, "Unable to read on socket")
-            })?;
+    pub fn connect_timeout(&self, addr: &SocketAddr, timeout: Duration) -> io::Result<()> {
+        self.set_nonblocking(true)?;
+        let r = unsafe {
+            let (addr, len) = addr.into_inner();
+            cvt(netc::connect(self.as_raw_fd(), addr.as_ptr(), len))
+        };
+        self.set_nonblocking(false)?;
 
-            if ret != 0 {
-                size += ret;
-            }
+        match r {
+            Ok(_) => return Ok(()),
+            // there's no ErrorKind for EINPROGRESS :(
+            Err(ref e) if e.raw_os_error() == Some(netc::errno::EINPROGRESS) => {}
+            Err(e) => return Err(e),
         }
 
-        Ok(size)
-    }
-
-    #[inline]
-    pub fn is_read_vectored(&self) -> bool {
-        true
-    }
-
-    pub fn write(&self, buffer: &[u8]) -> io::Result<usize> {
-        self.write_vectored(&[IoSlice::new(buffer)])
-    }
+        let mut pollfd = netc::pollfd { fd: self.as_raw_fd(), events: netc::POLLOUT, revents: 0 };
 
-    pub fn write_vectored(&self, ioslice: &[IoSlice<'_>]) -> io::Result<usize> {
-        let mut size: usize = 0;
-
-        for i in ioslice.iter() {
-            size += abi::tcpstream::write(*self.0.as_inner(), i).map_err(|_| {
-                io::const_io_error!(ErrorKind::Uncategorized, "Unable to write on socket")
-            })?;
+        if timeout.as_secs() == 0 && timeout.subsec_nanos() == 0 {
+            return Err(io::const_io_error!(
+                io::ErrorKind::InvalidInput,
+                "cannot set a 0 duration timeout",
+            ));
         }
 
-        Ok(size)
-    }
-
-    #[inline]
-    pub fn is_write_vectored(&self) -> bool {
-        true
-    }
-
-    pub fn peer_addr(&self) -> io::Result<SocketAddr> {
-        let (ipaddr, port) = abi::tcpstream::peer_addr(*self.0.as_inner())
-            .map_err(|_| io::const_io_error!(ErrorKind::Uncategorized, "peer_addr failed"))?;
+        let start = Instant::now();
 
-        let saddr = match ipaddr {
-            Ipv4(ref addr) => SocketAddr::new(IpAddr::V4(Ipv4Addr::from(addr.0)), port),
-            Ipv6(ref addr) => SocketAddr::new(IpAddr::V6(Ipv6Addr::from(addr.0)), port),
-            _ => {
-                return Err(io::const_io_error!(ErrorKind::Uncategorized, "peer_addr failed"));
+        loop {
+            let elapsed = start.elapsed();
+            if elapsed >= timeout {
+                return Err(io::const_io_error!(io::ErrorKind::TimedOut, "connection timed out"));
             }
-        };
-
-        Ok(saddr)
-    }
-
-    pub fn socket_addr(&self) -> io::Result<SocketAddr> {
-        unsupported()
-    }
-
-    pub fn shutdown(&self, how: Shutdown) -> io::Result<()> {
-        abi::tcpstream::shutdown(*self.0.as_inner(), how as i32)
-            .map_err(|_| io::const_io_error!(ErrorKind::Uncategorized, "unable to shutdown socket"))
-    }
-
-    pub fn duplicate(&self) -> io::Result<TcpStream> {
-        Ok(self.clone())
-    }
-
-    pub fn set_linger(&self, _linger: Option<Duration>) -> io::Result<()> {
-        unsupported()
-    }
-
-    pub fn linger(&self) -> io::Result<Option<Duration>> {
-        unsupported()
-    }
-
-    pub fn set_nodelay(&self, mode: bool) -> io::Result<()> {
-        abi::tcpstream::set_nodelay(*self.0.as_inner(), mode)
-            .map_err(|_| io::const_io_error!(ErrorKind::Uncategorized, "set_nodelay failed"))
-    }
-
-    pub fn nodelay(&self) -> io::Result<bool> {
-        abi::tcpstream::nodelay(*self.0.as_inner())
-            .map_err(|_| io::const_io_error!(ErrorKind::Uncategorized, "nodelay failed"))
-    }
-
-    pub fn set_ttl(&self, tll: u32) -> io::Result<()> {
-        abi::tcpstream::set_tll(*self.0.as_inner(), tll)
-            .map_err(|_| io::const_io_error!(ErrorKind::Uncategorized, "unable to set TTL"))
-    }
-
-    pub fn ttl(&self) -> io::Result<u32> {
-        abi::tcpstream::get_tll(*self.0.as_inner())
-            .map_err(|_| io::const_io_error!(ErrorKind::Uncategorized, "unable to get TTL"))
-    }
 
-    pub fn take_error(&self) -> io::Result<Option<io::Error>> {
-        unsupported()
-    }
-
-    pub fn set_nonblocking(&self, mode: bool) -> io::Result<()> {
-        abi::tcpstream::set_nonblocking(*self.0.as_inner(), mode).map_err(|_| {
-            io::const_io_error!(ErrorKind::Uncategorized, "unable to set blocking mode")
-        })
-    }
-}
-
-impl fmt::Debug for TcpStream {
-    fn fmt(&self, _f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        Ok(())
-    }
-}
-
-#[derive(Clone)]
-pub struct TcpListener(SocketAddr);
-
-impl TcpListener {
-    pub fn bind(addr: io::Result<&SocketAddr>) -> io::Result<TcpListener> {
-        let addr = addr?;
-
-        Ok(TcpListener(*addr))
-    }
-
-    pub fn socket_addr(&self) -> io::Result<SocketAddr> {
-        Ok(self.0)
-    }
-
-    pub fn accept(&self) -> io::Result<(TcpStream, SocketAddr)> {
-        let (handle, ipaddr, port) = abi::tcplistener::accept(self.0.port())
-            .map_err(|_| io::const_io_error!(ErrorKind::Uncategorized, "accept failed"))?;
-        let saddr = match ipaddr {
-            Ipv4(ref addr) => SocketAddr::new(IpAddr::V4(Ipv4Addr::from(addr.0)), port),
-            Ipv6(ref addr) => SocketAddr::new(IpAddr::V6(Ipv6Addr::from(addr.0)), port),
-            _ => {
-                return Err(io::const_io_error!(ErrorKind::Uncategorized, "accept failed"));
+            let timeout = timeout - elapsed;
+            let mut timeout = timeout
+                .as_secs()
+                .saturating_mul(1_000)
+                .saturating_add(timeout.subsec_nanos() as u64 / 1_000_000);
+            if timeout == 0 {
+                timeout = 1;
             }
-        };
-
-        Ok((TcpStream(Arc::new(Socket(handle))), saddr))
-    }
 
-    pub fn duplicate(&self) -> io::Result<TcpListener> {
-        Ok(self.clone())
-    }
-
-    pub fn set_ttl(&self, _: u32) -> io::Result<()> {
-        unsupported()
-    }
-
-    pub fn ttl(&self) -> io::Result<u32> {
-        unsupported()
-    }
-
-    pub fn set_only_v6(&self, _: bool) -> io::Result<()> {
-        unsupported()
+            let timeout = cmp::min(timeout, c_int::MAX as u64) as c_int;
+
+            match unsafe { netc::poll(&mut pollfd, 1, timeout) } {
+                -1 => {
+                    let err = io::Error::last_os_error();
+                    if err.kind() != io::ErrorKind::Interrupted {
+                        return Err(err);
+                    }
+                }
+                0 => {}
+                _ => {
+                    // linux returns POLLOUT|POLLERR|POLLHUP for refused connections (!), so look
+                    // for POLLHUP rather than read readiness
+                    if pollfd.revents & netc::POLLHUP != 0 {
+                        let e = self.take_error()?.unwrap_or_else(|| {
+                            io::const_io_error!(
+                                io::ErrorKind::Uncategorized,
+                                "no error set after POLLHUP",
+                            )
+                        });
+                        return Err(e);
+                    }
+
+                    return Ok(());
+                }
+            }
+        }
     }
 
-    pub fn only_v6(&self) -> io::Result<bool> {
-        unsupported()
+    pub fn accept(
+        &self,
+        storage: *mut netc::sockaddr,
+        len: *mut netc::socklen_t,
+    ) -> io::Result<Socket> {
+        let fd = cvt(unsafe { netc::accept(self.0.as_raw_fd(), storage, len) })?;
+        Ok(Socket(unsafe { FileDesc::from_raw_fd(fd) }))
     }
 
-    pub fn take_error(&self) -> io::Result<Option<io::Error>> {
-        unsupported()
+    pub fn duplicate(&self) -> io::Result<Socket> {
+        let fd = cvt(unsafe { netc::dup(self.0.as_raw_fd()) })?;
+        Ok(Socket(unsafe { FileDesc::from_raw_fd(fd) }))
     }
 
-    pub fn set_nonblocking(&self, _: bool) -> io::Result<()> {
-        unsupported()
+    fn recv_with_flags(&self, buf: &mut [u8], flags: i32) -> io::Result<usize> {
+        let ret =
+            cvt(unsafe { netc::recv(self.0.as_raw_fd(), buf.as_mut_ptr(), buf.len(), flags) })?;
+        Ok(ret as usize)
     }
-}
 
-impl fmt::Debug for TcpListener {
-    fn fmt(&self, _f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        Ok(())
+    pub fn read(&self, buf: &mut [u8]) -> io::Result<usize> {
+        self.recv_with_flags(buf, 0)
     }
-}
-
-pub struct UdpSocket(abi::Handle);
 
-impl UdpSocket {
-    pub fn bind(_: io::Result<&SocketAddr>) -> io::Result<UdpSocket> {
-        unsupported()
+    pub fn peek(&self, buf: &mut [u8]) -> io::Result<usize> {
+        self.recv_with_flags(buf, netc::MSG_PEEK)
     }
 
-    pub fn peer_addr(&self) -> io::Result<SocketAddr> {
-        unsupported()
-    }
+    pub fn read_vectored(&self, bufs: &mut [IoSliceMut<'_>]) -> io::Result<usize> {
+        let mut size: isize = 0;
 
-    pub fn socket_addr(&self) -> io::Result<SocketAddr> {
-        unsupported()
-    }
+        for i in bufs.iter_mut() {
+            let ret: isize =
+                cvt(unsafe { netc::read(self.0.as_raw_fd(), i.as_mut_ptr(), i.len()) })?;
 
-    pub fn recv_from(&self, _: &mut [u8]) -> io::Result<(usize, SocketAddr)> {
-        unsupported()
-    }
+            if ret != 0 {
+                size += ret;
+            }
+        }
 
-    pub fn peek_from(&self, _: &mut [u8]) -> io::Result<(usize, SocketAddr)> {
-        unsupported()
+        Ok(size.try_into().unwrap())
     }
 
-    pub fn send_to(&self, _: &[u8], _: &SocketAddr) -> io::Result<usize> {
-        unsupported()
+    #[inline]
+    pub fn is_read_vectored(&self) -> bool {
+        true
     }
 
-    pub fn duplicate(&self) -> io::Result<UdpSocket> {
-        unsupported()
-    }
+    fn recv_from_with_flags(&self, buf: &mut [u8], flags: i32) -> io::Result<(usize, SocketAddr)> {
+        let mut storage: netc::sockaddr_storage = unsafe { mem::zeroed() };
+        let mut addrlen = mem::size_of_val(&storage) as netc::socklen_t;
 
-    pub fn set_read_timeout(&self, _: Option<Duration>) -> io::Result<()> {
-        unsupported()
+        let n = cvt(unsafe {
+            netc::recvfrom(
+                self.as_raw_fd(),
+                buf.as_mut_ptr(),
+                buf.len(),
+                flags,
+                &mut storage as *mut _ as *mut _,
+                &mut addrlen,
+            )
+        })?;
+        Ok((n as usize, sockaddr_to_addr(&storage, addrlen as usize)?))
     }
 
-    pub fn set_write_timeout(&self, _: Option<Duration>) -> io::Result<()> {
-        unsupported()
+    pub fn recv_from(&self, buf: &mut [u8]) -> io::Result<(usize, SocketAddr)> {
+        self.recv_from_with_flags(buf, 0)
     }
 
-    pub fn read_timeout(&self) -> io::Result<Option<Duration>> {
-        unsupported()
+    pub fn peek_from(&self, buf: &mut [u8]) -> io::Result<(usize, SocketAddr)> {
+        self.recv_from_with_flags(buf, netc::MSG_PEEK)
     }
 
-    pub fn write_timeout(&self) -> io::Result<Option<Duration>> {
-        unsupported()
+    pub fn write(&self, buf: &[u8]) -> io::Result<usize> {
+        let sz = cvt(unsafe { netc::write(self.0.as_raw_fd(), buf.as_ptr(), buf.len()) })?;
+        Ok(sz.try_into().unwrap())
     }
 
-    pub fn set_broadcast(&self, _: bool) -> io::Result<()> {
-        unsupported()
-    }
+    pub fn write_vectored(&self, bufs: &[IoSlice<'_>]) -> io::Result<usize> {
+        let mut size: isize = 0;
 
-    pub fn broadcast(&self) -> io::Result<bool> {
-        unsupported()
-    }
+        for i in bufs.iter() {
+            size += cvt(unsafe { netc::write(self.0.as_raw_fd(), i.as_ptr(), i.len()) })?;
+        }
 
-    pub fn set_multicast_loop_v4(&self, _: bool) -> io::Result<()> {
-        unsupported()
+        Ok(size.try_into().unwrap())
     }
 
-    pub fn multicast_loop_v4(&self) -> io::Result<bool> {
-        unsupported()
+    pub fn is_write_vectored(&self) -> bool {
+        true
     }
 
-    pub fn set_multicast_ttl_v4(&self, _: u32) -> io::Result<()> {
-        unsupported()
-    }
+    pub fn set_timeout(&self, dur: Option<Duration>, kind: i32) -> io::Result<()> {
+        let timeout = match dur {
+            Some(dur) => {
+                if dur.as_secs() == 0 && dur.subsec_nanos() == 0 {
+                    return Err(io::const_io_error!(
+                        io::ErrorKind::InvalidInput,
+                        "cannot set a 0 duration timeout",
+                    ));
+                }
+
+                let secs = if dur.as_secs() > netc::time_t::MAX as u64 {
+                    netc::time_t::MAX
+                } else {
+                    dur.as_secs() as netc::time_t
+                };
+                let mut timeout = netc::timeval {
+                    tv_sec: secs,
+                    tv_usec: dur.subsec_micros() as netc::suseconds_t,
+                };
+                if timeout.tv_sec == 0 && timeout.tv_usec == 0 {
+                    timeout.tv_usec = 1;
+                }
+                timeout
+            }
+            None => netc::timeval { tv_sec: 0, tv_usec: 0 },
+        };
 
-    pub fn multicast_ttl_v4(&self) -> io::Result<u32> {
-        unsupported()
+        setsockopt(self, netc::SOL_SOCKET, kind, timeout)
     }
 
-    pub fn set_multicast_loop_v6(&self, _: bool) -> io::Result<()> {
-        unsupported()
+    pub fn timeout(&self, kind: i32) -> io::Result<Option<Duration>> {
+        let raw: netc::timeval = getsockopt(self, netc::SOL_SOCKET, kind)?;
+        if raw.tv_sec == 0 && raw.tv_usec == 0 {
+            Ok(None)
+        } else {
+            let sec = raw.tv_sec as u64;
+            let nsec = (raw.tv_usec as u32) * 1000;
+            Ok(Some(Duration::new(sec, nsec)))
+        }
     }
 
-    pub fn multicast_loop_v6(&self) -> io::Result<bool> {
-        unsupported()
+    pub fn shutdown(&self, how: Shutdown) -> io::Result<()> {
+        let how = match how {
+            Shutdown::Write => netc::SHUT_WR,
+            Shutdown::Read => netc::SHUT_RD,
+            Shutdown::Both => netc::SHUT_RDWR,
+        };
+        cvt(unsafe { netc::shutdown_socket(self.as_raw_fd(), how) })?;
+        Ok(())
     }
 
-    pub fn join_multicast_v4(&self, _: &Ipv4Addr, _: &Ipv4Addr) -> io::Result<()> {
-        unsupported()
-    }
+    pub fn set_linger(&self, linger: Option<Duration>) -> io::Result<()> {
+        let linger = netc::linger {
+            l_onoff: linger.is_some() as i32,
+            l_linger: linger.unwrap_or_default().as_secs() as libc::c_int,
+        };
 
-    pub fn join_multicast_v6(&self, _: &Ipv6Addr, _: u32) -> io::Result<()> {
-        unsupported()
+        setsockopt(self, netc::SOL_SOCKET, netc::SO_LINGER, linger)
     }
 
-    pub fn leave_multicast_v4(&self, _: &Ipv4Addr, _: &Ipv4Addr) -> io::Result<()> {
-        unsupported()
-    }
+    pub fn linger(&self) -> io::Result<Option<Duration>> {
+        let val: netc::linger = getsockopt(self, netc::SOL_SOCKET, netc::SO_LINGER)?;
 
-    pub fn leave_multicast_v6(&self, _: &Ipv6Addr, _: u32) -> io::Result<()> {
-        unsupported()
+        Ok((val.l_onoff != 0).then(|| Duration::from_secs(val.l_linger as u64)))
     }
 
-    pub fn set_ttl(&self, _: u32) -> io::Result<()> {
-        unsupported()
+    pub fn set_nodelay(&self, nodelay: bool) -> io::Result<()> {
+        let value: i32 = if nodelay { 1 } else { 0 };
+        setsockopt(self, netc::IPPROTO_TCP, netc::TCP_NODELAY, value)
     }
 
-    pub fn ttl(&self) -> io::Result<u32> {
-        unsupported()
+    pub fn nodelay(&self) -> io::Result<bool> {
+        let raw: i32 = getsockopt(self, netc::IPPROTO_TCP, netc::TCP_NODELAY)?;
+        Ok(raw != 0)
+    }
+
+    pub fn set_nonblocking(&self, nonblocking: bool) -> io::Result<()> {
+        let mut nonblocking: i32 = if nonblocking { 1 } else { 0 };
+        cvt(unsafe {
+            netc::ioctl(
+                self.as_raw_fd(),
+                netc::FIONBIO,
+                &mut nonblocking as *mut _ as *mut core::ffi::c_void,
+            )
+        })
+        .map(drop)
     }
 
     pub fn take_error(&self) -> io::Result<Option<io::Error>> {
-        unsupported()
-    }
-
-    pub fn set_nonblocking(&self, _: bool) -> io::Result<()> {
-        unsupported()
-    }
-
-    pub fn recv(&self, _: &mut [u8]) -> io::Result<usize> {
-        unsupported()
-    }
-
-    pub fn peek(&self, _: &mut [u8]) -> io::Result<usize> {
-        unsupported()
+        unimplemented!()
     }
 
-    pub fn send(&self, _: &[u8]) -> io::Result<usize> {
-        unsupported()
-    }
-
-    pub fn connect(&self, _: io::Result<&SocketAddr>) -> io::Result<()> {
-        unsupported()
+    // This is used by sys_common code to abstract over Windows and Unix.
+    pub fn as_raw(&self) -> RawFd {
+        self.0.as_raw_fd()
     }
 }
 
-impl fmt::Debug for UdpSocket {
-    fn fmt(&self, _f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        Ok(())
+impl AsInner<FileDesc> for Socket {
+    fn as_inner(&self) -> &FileDesc {
+        &self.0
     }
 }
 
-pub struct LookupHost(!);
-
-impl LookupHost {
-    pub fn port(&self) -> u16 {
+impl IntoInner<FileDesc> for Socket {
+    fn into_inner(self) -> FileDesc {
         self.0
     }
 }
 
-impl Iterator for LookupHost {
-    type Item = SocketAddr;
-    fn next(&mut self) -> Option<SocketAddr> {
-        self.0
+impl FromInner<FileDesc> for Socket {
+    fn from_inner(file_desc: FileDesc) -> Self {
+        Self(file_desc)
     }
 }
 
-impl TryFrom<&str> for LookupHost {
-    type Error = io::Error;
-
-    fn try_from(_v: &str) -> io::Result<LookupHost> {
-        unsupported()
+impl AsFd for Socket {
+    fn as_fd(&self) -> BorrowedFd<'_> {
+        self.0.as_fd()
     }
 }
 
-impl<'a> TryFrom<(&'a str, u16)> for LookupHost {
-    type Error = io::Error;
-
-    fn try_from(_v: (&'a str, u16)) -> io::Result<LookupHost> {
-        unsupported()
+impl AsRawFd for Socket {
+    fn as_raw_fd(&self) -> RawFd {
+        self.0.as_raw_fd()
     }
 }
-
-#[allow(nonstandard_style)]
-pub mod netc {
-    pub const AF_INET: u8 = 0;
-    pub const AF_INET6: u8 = 1;
-    pub type sa_family_t = u8;
-
-    #[derive(Copy, Clone)]
-    pub struct in_addr {
-        pub s_addr: u32,
-    }
-
-    #[derive(Copy, Clone)]
-    pub struct sockaddr_in {
-        pub sin_family: sa_family_t,
-        pub sin_port: u16,
-        pub sin_addr: in_addr,
-    }
-
-    #[derive(Copy, Clone)]
-    pub struct in6_addr {
-        pub s6_addr: [u8; 16],
-    }
-
-    #[derive(Copy, Clone)]
-    pub struct sockaddr_in6 {
-        pub sin6_family: sa_family_t,
-        pub sin6_port: u16,
-        pub sin6_addr: in6_addr,
-        pub sin6_flowinfo: u32,
-        pub sin6_scope_id: u32,
-    }
-
-    #[derive(Copy, Clone)]
-    pub struct sockaddr {}
-}
diff --git a/library/std/src/sys/hermit/os.rs b/library/std/src/sys/hermit/os.rs
index 8f927df85..e53dbae61 100644
--- a/library/std/src/sys/hermit/os.rs
+++ b/library/std/src/sys/hermit/os.rs
@@ -4,7 +4,7 @@ use crate::ffi::{CStr, OsStr, OsString};
 use crate::fmt;
 use crate::io;
 use crate::marker::PhantomData;
-use crate::os::unix::ffi::OsStringExt;
+use crate::os::hermit::ffi::OsStringExt;
 use crate::path::{self, PathBuf};
 use crate::str;
 use crate::sync::Mutex;
diff --git a/library/std/src/sys/hermit/thread.rs b/library/std/src/sys/hermit/thread.rs
index 8f65544a9..2507f7069 100644
--- a/library/std/src/sys/hermit/thread.rs
+++ b/library/std/src/sys/hermit/thread.rs
@@ -27,10 +27,10 @@ impl Thread {
         p: Box<dyn FnOnce()>,
         core_id: isize,
     ) -> io::Result<Thread> {
-        let p = Box::into_raw(box p);
+        let p = Box::into_raw(Box::new(p));
         let tid = abi::spawn2(
             thread_start,
-            p as usize,
+            p.expose_addr(),
             abi::Priority::into(abi::NORMAL_PRIO),
             stack,
             core_id,
diff --git a/library/std/src/sys/hermit/thread_local_dtor.rs b/library/std/src/sys/hermit/thread_local_dtor.rs
index 9b683fce1..613266b95 100644
--- a/library/std/src/sys/hermit/thread_local_dtor.rs
+++ b/library/std/src/sys/hermit/thread_local_dtor.rs
@@ -5,32 +5,23 @@
 // The this solution works like the implementation of macOS and
 // doesn't additional OS support
 
-use crate::cell::Cell;
-use crate::ptr;
+use crate::mem;
 
 #[thread_local]
-static DTORS: Cell<*mut List> = Cell::new(ptr::null_mut());
-
-type List = Vec<(*mut u8, unsafe extern "C" fn(*mut u8))>;
+static mut DTORS: Vec<(*mut u8, unsafe extern "C" fn(*mut u8))> = Vec::new();
 
 pub unsafe fn register_dtor(t: *mut u8, dtor: unsafe extern "C" fn(*mut u8)) {
-    if DTORS.get().is_null() {
-        let v: Box<List> = box Vec::new();
-        DTORS.set(Box::into_raw(v));
-    }
-
-    let list: &mut List = &mut *DTORS.get();
+    let list = &mut DTORS;
     list.push((t, dtor));
 }
 
 // every thread call this function to run through all possible destructors
 pub unsafe fn run_dtors() {
-    let mut ptr = DTORS.replace(ptr::null_mut());
-    while !ptr.is_null() {
-        let list = Box::from_raw(ptr);
-        for (ptr, dtor) in list.into_iter() {
+    let mut list = mem::take(&mut DTORS);
+    while !list.is_empty() {
+        for (ptr, dtor) in list {
             dtor(ptr);
         }
-        ptr = DTORS.replace(ptr::null_mut());
+        list = mem::take(&mut DTORS);
     }
 }
diff --git a/library/std/src/sys/hermit/time.rs b/library/std/src/sys/hermit/time.rs
index c17e6c8af..32ddc4346 100644
--- a/library/std/src/sys/hermit/time.rs
+++ b/library/std/src/sys/hermit/time.rs
@@ -1,6 +1,7 @@
 #![allow(dead_code)]
 
 use crate::cmp::Ordering;
+use crate::ops::{Add, AddAssign, Sub, SubAssign};
 use crate::sys::hermit::abi;
 use crate::sys::hermit::abi::timespec;
 use crate::sys::hermit::abi::{CLOCK_MONOTONIC, CLOCK_REALTIME, NSEC_PER_SEC};
@@ -102,55 +103,122 @@ impl Hash for Timespec {
 }
 
 #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Debug, Hash)]
-pub struct Instant {
-    t: Timespec,
-}
+pub struct Instant(Timespec);
 
 impl Instant {
     pub fn now() -> Instant {
         let mut time: Timespec = Timespec::zero();
         let _ = unsafe { abi::clock_gettime(CLOCK_MONOTONIC, &mut time.t as *mut timespec) };
 
-        Instant { t: time }
+        Instant(time)
+    }
+
+    #[stable(feature = "time2", since = "1.8.0")]
+    pub fn elapsed(&self) -> Duration {
+        Instant::now() - *self
+    }
+
+    pub fn duration_since(&self, earlier: Instant) -> Duration {
+        self.checked_duration_since(earlier).unwrap_or_default()
+    }
+
+    pub fn checked_duration_since(&self, earlier: Instant) -> Option<Duration> {
+        self.checked_sub_instant(&earlier)
     }
 
     pub fn checked_sub_instant(&self, other: &Instant) -> Option<Duration> {
-        self.t.sub_timespec(&other.t).ok()
+        self.0.sub_timespec(&other.0).ok()
     }
 
     pub fn checked_add_duration(&self, other: &Duration) -> Option<Instant> {
-        Some(Instant { t: self.t.checked_add_duration(other)? })
+        Some(Instant(self.0.checked_add_duration(other)?))
     }
 
     pub fn checked_sub_duration(&self, other: &Duration) -> Option<Instant> {
-        Some(Instant { t: self.t.checked_sub_duration(other)? })
+        Some(Instant(self.0.checked_sub_duration(other)?))
+    }
+
+    pub fn checked_add(&self, duration: Duration) -> Option<Instant> {
+        self.0.checked_add_duration(&duration).map(Instant)
+    }
+
+    pub fn checked_sub(&self, duration: Duration) -> Option<Instant> {
+        self.0.checked_sub_duration(&duration).map(Instant)
     }
 }
 
-#[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash, Debug)]
-pub struct SystemTime {
-    t: Timespec,
+impl Add<Duration> for Instant {
+    type Output = Instant;
+
+    /// # Panics
+    ///
+    /// This function may panic if the resulting point in time cannot be represented by the
+    /// underlying data structure. See [`Instant::checked_add`] for a version without panic.
+    fn add(self, other: Duration) -> Instant {
+        self.checked_add(other).expect("overflow when adding duration to instant")
+    }
 }
 
-pub const UNIX_EPOCH: SystemTime = SystemTime { t: Timespec::zero() };
+impl AddAssign<Duration> for Instant {
+    fn add_assign(&mut self, other: Duration) {
+        *self = *self + other;
+    }
+}
+
+impl Sub<Duration> for Instant {
+    type Output = Instant;
+
+    fn sub(self, other: Duration) -> Instant {
+        self.checked_sub(other).expect("overflow when subtracting duration from instant")
+    }
+}
+
+impl SubAssign<Duration> for Instant {
+    fn sub_assign(&mut self, other: Duration) {
+        *self = *self - other;
+    }
+}
+
+impl Sub<Instant> for Instant {
+    type Output = Duration;
+
+    /// Returns the amount of time elapsed from another instant to this one,
+    /// or zero duration if that instant is later than this one.
+    ///
+    /// # Panics
+    ///
+    /// Previous rust versions panicked when `other` was later than `self`. Currently this
+    /// method saturates. Future versions may reintroduce the panic in some circumstances.
+    /// See [Monotonicity].
+    ///
+    /// [Monotonicity]: Instant#monotonicity
+    fn sub(self, other: Instant) -> Duration {
+        self.duration_since(other)
+    }
+}
+
+#[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash, Debug)]
+pub struct SystemTime(Timespec);
+
+pub const UNIX_EPOCH: SystemTime = SystemTime(Timespec::zero());
 
 impl SystemTime {
     pub fn now() -> SystemTime {
         let mut time: Timespec = Timespec::zero();
         let _ = unsafe { abi::clock_gettime(CLOCK_REALTIME, &mut time.t as *mut timespec) };
 
-        SystemTime { t: time }
+        SystemTime(time)
     }
 
     pub fn sub_time(&self, other: &SystemTime) -> Result<Duration, Duration> {
-        self.t.sub_timespec(&other.t)
+        self.0.sub_timespec(&other.0)
     }
 
     pub fn checked_add_duration(&self, other: &Duration) -> Option<SystemTime> {
-        Some(SystemTime { t: self.t.checked_add_duration(other)? })
+        Some(SystemTime(self.0.checked_add_duration(other)?))
     }
 
     pub fn checked_sub_duration(&self, other: &Duration) -> Option<SystemTime> {
-        Some(SystemTime { t: self.t.checked_sub_duration(other)? })
+        Some(SystemTime(self.0.checked_sub_duration(other)?))
     }
 }
diff --git a/library/std/src/sys/itron/thread.rs b/library/std/src/sys/itron/thread.rs
index 19350b83f..ae0f71853 100644
--- a/library/std/src/sys/itron/thread.rs
+++ b/library/std/src/sys/itron/thread.rs
@@ -247,7 +247,7 @@ impl Thread {
                 // [FINISHED → JOINED]
                 // To synchronize with the child task's memory accesses to
                 // `inner` up to the point of the assignment of `FINISHED`,
-                // `Ordering::Acquire` must be used for the above `swap` call`.
+                // `Ordering::Acquire` must be used for the above `swap` call.
             }
             _ => unsafe { hint::unreachable_unchecked() },
         }
diff --git a/library/std/src/sys/itron/thread_parking.rs b/library/std/src/sys/itron/thread_parking.rs
new file mode 100644
index 000000000..fe9934439
--- /dev/null
+++ b/library/std/src/sys/itron/thread_parking.rs
@@ -0,0 +1,37 @@
+use super::abi;
+use super::error::expect_success_aborting;
+use super::time::with_tmos;
+use crate::time::Duration;
+
+pub type ThreadId = abi::ID;
+
+pub use super::task::current_task_id_aborting as current;
+
+pub fn park(_hint: usize) {
+    match unsafe { abi::slp_tsk() } {
+        abi::E_OK | abi::E_RLWAI => {}
+        err => {
+            expect_success_aborting(err, &"slp_tsk");
+        }
+    }
+}
+
+pub fn park_timeout(dur: Duration, _hint: usize) {
+    match with_tmos(dur, |tmo| unsafe { abi::tslp_tsk(tmo) }) {
+        abi::E_OK | abi::E_RLWAI | abi::E_TMOUT => {}
+        err => {
+            expect_success_aborting(err, &"tslp_tsk");
+        }
+    }
+}
+
+pub fn unpark(id: ThreadId, _hint: usize) {
+    match unsafe { abi::wup_tsk(id) } {
+        // It is allowed to try to wake up a destroyed or unrelated task, so we ignore all
+        // errors that could result from that situation.
+        abi::E_OK | abi::E_NOEXS | abi::E_OBJ | abi::E_QOVR => {}
+        err => {
+            expect_success_aborting(err, &"wup_tsk");
+        }
+    }
+}
diff --git a/library/std/src/sys/itron/wait_flag.rs b/library/std/src/sys/itron/wait_flag.rs
deleted file mode 100644
index e432edd20..000000000
--- a/library/std/src/sys/itron/wait_flag.rs
+++ /dev/null
@@ -1,72 +0,0 @@
-use crate::mem::MaybeUninit;
-use crate::time::Duration;
-
-use super::{
-    abi,
-    error::{expect_success, fail},
-    time::with_tmos,
-};
-
-const CLEAR: abi::FLGPTN = 0;
-const RAISED: abi::FLGPTN = 1;
-
-/// A thread parking primitive that is not susceptible to race conditions,
-/// but provides no atomic ordering guarantees and allows only one `raise` per wait.
-pub struct WaitFlag {
-    flag: abi::ID,
-}
-
-impl WaitFlag {
-    /// Creates a new wait flag.
-    pub fn new() -> WaitFlag {
-        let flag = expect_success(
-            unsafe {
-                abi::acre_flg(&abi::T_CFLG {
-                    flgatr: abi::TA_FIFO | abi::TA_WSGL | abi::TA_CLR,
-                    iflgptn: CLEAR,
-                })
-            },
-            &"acre_flg",
-        );
-
-        WaitFlag { flag }
-    }
-
-    /// Wait for the wait flag to be raised.
-    pub fn wait(&self) {
-        let mut token = MaybeUninit::uninit();
-        expect_success(
-            unsafe { abi::wai_flg(self.flag, RAISED, abi::TWF_ORW, token.as_mut_ptr()) },
-            &"wai_flg",
-        );
-    }
-
-    /// Wait for the wait flag to be raised or the timeout to occur.
-    ///
-    /// Returns whether the flag was raised (`true`) or the operation timed out (`false`).
-    pub fn wait_timeout(&self, dur: Duration) -> bool {
-        let mut token = MaybeUninit::uninit();
-        let res = with_tmos(dur, |tmout| unsafe {
-            abi::twai_flg(self.flag, RAISED, abi::TWF_ORW, token.as_mut_ptr(), tmout)
-        });
-
-        match res {
-            abi::E_OK => true,
-            abi::E_TMOUT => false,
-            error => fail(error, &"twai_flg"),
-        }
-    }
-
-    /// Raise the wait flag.
-    ///
-    /// Calls to this function should be balanced with the number of successful waits.
-    pub fn raise(&self) {
-        expect_success(unsafe { abi::set_flg(self.flag, RAISED) }, &"set_flg");
-    }
-}
-
-impl Drop for WaitFlag {
-    fn drop(&mut self) {
-        expect_success(unsafe { abi::del_flg(self.flag) }, &"del_flg");
-    }
-}
diff --git a/library/std/src/sys/solid/mod.rs b/library/std/src/sys/solid/mod.rs
index 5867979a2..923d27fd9 100644
--- a/library/std/src/sys/solid/mod.rs
+++ b/library/std/src/sys/solid/mod.rs
@@ -13,9 +13,9 @@ mod itron {
     pub(super) mod spin;
     pub(super) mod task;
     pub mod thread;
+    pub mod thread_parking;
     pub(super) mod time;
     use super::unsupported;
-    pub mod wait_flag;
 }
 
 pub mod alloc;
@@ -43,8 +43,8 @@ pub use self::itron::thread;
 pub mod memchr;
 pub mod thread_local_dtor;
 pub mod thread_local_key;
+pub use self::itron::thread_parking;
 pub mod time;
-pub use self::itron::wait_flag;
 
 mod rwlock;
 
diff --git a/library/std/src/sys/solid/thread_local_dtor.rs b/library/std/src/sys/solid/thread_local_dtor.rs
index 973564570..bad14bb37 100644
--- a/library/std/src/sys/solid/thread_local_dtor.rs
+++ b/library/std/src/sys/solid/thread_local_dtor.rs
@@ -5,43 +5,35 @@
 
 use super::{abi, itron::task};
 use crate::cell::Cell;
-use crate::ptr;
+use crate::mem;
 
 #[thread_local]
-static DTORS: Cell<*mut List> = Cell::new(ptr::null_mut());
+static REGISTERED: Cell<bool> = Cell::new(false);
 
-type List = Vec<(*mut u8, unsafe extern "C" fn(*mut u8))>;
+#[thread_local]
+static mut DTORS: Vec<(*mut u8, unsafe extern "C" fn(*mut u8))> = Vec::new();
 
 pub unsafe fn register_dtor(t: *mut u8, dtor: unsafe extern "C" fn(*mut u8)) {
-    if DTORS.get().is_null() {
+    if !REGISTERED.get() {
         let tid = task::current_task_id_aborting();
-        let v: Box<List> = box Vec::new();
-        DTORS.set(Box::into_raw(v));
-
         // Register `tls_dtor` to make sure the TLS destructors are called
         // for tasks created by other means than `std::thread`
         unsafe { abi::SOLID_TLS_AddDestructor(tid as i32, tls_dtor) };
+        REGISTERED.set(true);
     }
 
-    let list: &mut List = unsafe { &mut *DTORS.get() };
+    let list = unsafe { &mut DTORS };
     list.push((t, dtor));
 }
 
 pub unsafe fn run_dtors() {
-    let ptr = DTORS.get();
-    if !ptr.is_null() {
-        // Swap the destructor list, call all registered destructors,
-        // and repeat this until the list becomes permanently empty.
-        while let Some(list) = Some(crate::mem::replace(unsafe { &mut *ptr }, Vec::new()))
-            .filter(|list| !list.is_empty())
-        {
-            for (ptr, dtor) in list.into_iter() {
-                unsafe { dtor(ptr) };
-            }
+    let mut list = mem::take(unsafe { &mut DTORS });
+    while !list.is_empty() {
+        for (ptr, dtor) in list {
+            unsafe { dtor(ptr) };
         }
 
-        // Drop the destructor list
-        unsafe { Box::from_raw(DTORS.replace(ptr::null_mut())) };
+        list = mem::take(unsafe { &mut DTORS });
     }
 }
 
diff --git a/library/std/src/sys/unix/args.rs b/library/std/src/sys/unix/args.rs
index a342f0f5e..3d79058b3 100644
--- a/library/std/src/sys/unix/args.rs
+++ b/library/std/src/sys/unix/args.rs
@@ -69,7 +69,8 @@ impl DoubleEndedIterator for Args {
     target_os = "fuchsia",
     target_os = "redox",
     target_os = "vxworks",
-    target_os = "horizon"
+    target_os = "horizon",
+    target_os = "nto",
 ))]
 mod imp {
     use super::Args;
@@ -141,12 +142,28 @@ mod imp {
             // list.
             let argv = ARGV.load(Ordering::Relaxed);
             let argc = if argv.is_null() { 0 } else { ARGC.load(Ordering::Relaxed) };
-            (0..argc)
-                .map(|i| {
-                    let cstr = CStr::from_ptr(*argv.offset(i) as *const libc::c_char);
-                    OsStringExt::from_vec(cstr.to_bytes().to_vec())
-                })
-                .collect()
+            let mut args = Vec::with_capacity(argc as usize);
+            for i in 0..argc {
+                let ptr = *argv.offset(i) as *const libc::c_char;
+
+                // Some C commandline parsers (e.g. GLib and Qt) are replacing already
+                // handled arguments in `argv` with `NULL` and move them to the end. That
+                // means that `argc` might be bigger than the actual number of non-`NULL`
+                // pointers in `argv` at this point.
+                //
+                // To handle this we simply stop iterating at the first `NULL` argument.
+                //
+                // `argv` is also guaranteed to be `NULL`-terminated so any non-`NULL` arguments
+                // after the first `NULL` can safely be ignored.
+                if ptr.is_null() {
+                    break;
+                }
+
+                let cstr = CStr::from_ptr(ptr);
+                args.push(OsStringExt::from_vec(cstr.to_bytes().to_vec()));
+            }
+
+            args
         }
     }
 }
diff --git a/library/std/src/sys/unix/env.rs b/library/std/src/sys/unix/env.rs
index c9ba661c8..1a9276f11 100644
--- a/library/std/src/sys/unix/env.rs
+++ b/library/std/src/sys/unix/env.rs
@@ -185,6 +185,17 @@ pub mod os {
     pub const EXE_EXTENSION: &str = "";
 }
 
+#[cfg(target_os = "nto")]
+pub mod os {
+    pub const FAMILY: &str = "unix";
+    pub const OS: &str = "nto";
+    pub const DLL_PREFIX: &str = "lib";
+    pub const DLL_SUFFIX: &str = ".so";
+    pub const DLL_EXTENSION: &str = "so";
+    pub const EXE_SUFFIX: &str = "";
+    pub const EXE_EXTENSION: &str = "";
+}
+
 #[cfg(target_os = "redox")]
 pub mod os {
     pub const FAMILY: &str = "unix";
diff --git a/library/std/src/sys/unix/fd.rs b/library/std/src/sys/unix/fd.rs
index dbaa3c33e..9874af4d3 100644
--- a/library/std/src/sys/unix/fd.rs
+++ b/library/std/src/sys/unix/fd.rs
@@ -53,7 +53,12 @@ const fn max_iov() -> usize {
     libc::IOV_MAX as usize
 }
 
-#[cfg(any(target_os = "android", target_os = "emscripten", target_os = "linux"))]
+#[cfg(any(
+    target_os = "android",
+    target_os = "emscripten",
+    target_os = "linux",
+    target_os = "nto",
+))]
 const fn max_iov() -> usize {
     libc::UIO_MAXIOV as usize
 }
@@ -67,6 +72,7 @@ const fn max_iov() -> usize {
     target_os = "linux",
     target_os = "macos",
     target_os = "netbsd",
+    target_os = "nto",
     target_os = "openbsd",
     target_os = "horizon",
     target_os = "watchos",
@@ -92,7 +98,7 @@ impl FileDesc {
         let ret = cvt(unsafe {
             libc::readv(
                 self.as_raw_fd(),
-                bufs.as_ptr() as *const libc::iovec,
+                bufs.as_mut_ptr() as *mut libc::iovec as *const libc::iovec,
                 cmp::min(bufs.len(), max_iov()) as libc::c_int,
             )
         })?;
@@ -101,7 +107,7 @@ impl FileDesc {
 
     #[cfg(any(target_os = "espidf", target_os = "horizon"))]
     pub fn read_vectored(&self, bufs: &mut [IoSliceMut<'_>]) -> io::Result<usize> {
-        return crate::io::default_read_vectored(|b| self.read(b), bufs);
+        io::default_read_vectored(|b| self.read(b), bufs)
     }
 
     #[inline]
@@ -147,6 +153,95 @@ impl FileDesc {
         Ok(())
     }
 
+    #[cfg(any(
+        target_os = "emscripten",
+        target_os = "freebsd",
+        target_os = "fuchsia",
+        target_os = "illumos",
+        target_os = "linux",
+        target_os = "netbsd",
+    ))]
+    pub fn read_vectored_at(&self, bufs: &mut [IoSliceMut<'_>], offset: u64) -> io::Result<usize> {
+        let ret = cvt(unsafe {
+            libc::preadv(
+                self.as_raw_fd(),
+                bufs.as_mut_ptr() as *mut libc::iovec as *const libc::iovec,
+                cmp::min(bufs.len(), max_iov()) as libc::c_int,
+                offset as _,
+            )
+        })?;
+        Ok(ret as usize)
+    }
+
+    #[cfg(not(any(
+        target_os = "android",
+        target_os = "emscripten",
+        target_os = "freebsd",
+        target_os = "fuchsia",
+        target_os = "illumos",
+        target_os = "ios",
+        target_os = "linux",
+        target_os = "macos",
+        target_os = "netbsd",
+    )))]
+    pub fn read_vectored_at(&self, bufs: &mut [IoSliceMut<'_>], offset: u64) -> io::Result<usize> {
+        io::default_read_vectored(|b| self.read_at(b, offset), bufs)
+    }
+
+    // We support some old Android versions that do not have `preadv` in libc,
+    // so we use weak linkage and fallback to a direct syscall if not available.
+    //
+    // On 32-bit targets, we don't want to deal with weird ABI issues around
+    // passing 64-bits parameters to syscalls, so we fallback to the default
+    // implementation if `preadv` is not available.
+    #[cfg(all(target_os = "android", target_pointer_width = "64"))]
+    pub fn read_vectored_at(&self, bufs: &mut [IoSliceMut<'_>], offset: u64) -> io::Result<usize> {
+        super::weak::syscall! {
+            fn preadv(
+                fd: libc::c_int,
+                iovec: *const libc::iovec,
+                n_iovec: libc::c_int,
+                offset: off64_t
+            ) -> isize
+        }
+
+        let ret = cvt(unsafe {
+            preadv(
+                self.as_raw_fd(),
+                bufs.as_mut_ptr() as *mut libc::iovec as *const libc::iovec,
+                cmp::min(bufs.len(), max_iov()) as libc::c_int,
+                offset as _,
+            )
+        })?;
+        Ok(ret as usize)
+    }
+
+    // We support old MacOS and iOS versions that do not have `preadv`. There is
+    // no `syscall` possible in these platform.
+    #[cfg(any(
+        all(target_os = "android", target_pointer_width = "32"),
+        target_os = "ios",
+        target_os = "macos",
+    ))]
+    pub fn read_vectored_at(&self, bufs: &mut [IoSliceMut<'_>], offset: u64) -> io::Result<usize> {
+        super::weak::weak!(fn preadv64(libc::c_int, *const libc::iovec, libc::c_int, off64_t) -> isize);
+
+        match preadv64.get() {
+            Some(preadv) => {
+                let ret = cvt(unsafe {
+                    preadv(
+                        self.as_raw_fd(),
+                        bufs.as_mut_ptr() as *mut libc::iovec as *const libc::iovec,
+                        cmp::min(bufs.len(), max_iov()) as libc::c_int,
+                        offset as _,
+                    )
+                })?;
+                Ok(ret as usize)
+            }
+            None => io::default_read_vectored(|b| self.read_at(b, offset), bufs),
+        }
+    }
+
     pub fn write(&self, buf: &[u8]) -> io::Result<usize> {
         let ret = cvt(unsafe {
             libc::write(
@@ -172,7 +267,7 @@ impl FileDesc {
 
     #[cfg(any(target_os = "espidf", target_os = "horizon"))]
     pub fn write_vectored(&self, bufs: &[IoSlice<'_>]) -> io::Result<usize> {
-        return crate::io::default_write_vectored(|b| self.write(b), bufs);
+        io::default_write_vectored(|b| self.write(b), bufs)
     }
 
     #[inline]
@@ -197,9 +292,93 @@ impl FileDesc {
         }
     }
 
-    #[cfg(target_os = "linux")]
-    pub fn get_cloexec(&self) -> io::Result<bool> {
-        unsafe { Ok((cvt(libc::fcntl(self.as_raw_fd(), libc::F_GETFD))? & libc::FD_CLOEXEC) != 0) }
+    #[cfg(any(
+        target_os = "emscripten",
+        target_os = "freebsd",
+        target_os = "fuchsia",
+        target_os = "illumos",
+        target_os = "linux",
+        target_os = "netbsd",
+    ))]
+    pub fn write_vectored_at(&self, bufs: &[IoSlice<'_>], offset: u64) -> io::Result<usize> {
+        let ret = cvt(unsafe {
+            libc::pwritev(
+                self.as_raw_fd(),
+                bufs.as_ptr() as *const libc::iovec,
+                cmp::min(bufs.len(), max_iov()) as libc::c_int,
+                offset as _,
+            )
+        })?;
+        Ok(ret as usize)
+    }
+
+    #[cfg(not(any(
+        target_os = "android",
+        target_os = "emscripten",
+        target_os = "freebsd",
+        target_os = "fuchsia",
+        target_os = "illumos",
+        target_os = "ios",
+        target_os = "linux",
+        target_os = "macos",
+        target_os = "netbsd",
+    )))]
+    pub fn write_vectored_at(&self, bufs: &[IoSlice<'_>], offset: u64) -> io::Result<usize> {
+        io::default_write_vectored(|b| self.write_at(b, offset), bufs)
+    }
+
+    // We support some old Android versions that do not have `pwritev` in libc,
+    // so we use weak linkage and fallback to a direct syscall if not available.
+    //
+    // On 32-bit targets, we don't want to deal with weird ABI issues around
+    // passing 64-bits parameters to syscalls, so we fallback to the default
+    // implementation if `pwritev` is not available.
+    #[cfg(all(target_os = "android", target_pointer_width = "64"))]
+    pub fn write_vectored_at(&self, bufs: &[IoSlice<'_>], offset: u64) -> io::Result<usize> {
+        super::weak::syscall! {
+            fn pwritev(
+                fd: libc::c_int,
+                iovec: *const libc::iovec,
+                n_iovec: libc::c_int,
+                offset: off64_t
+            ) -> isize
+        }
+
+        let ret = cvt(unsafe {
+            pwritev(
+                self.as_raw_fd(),
+                bufs.as_ptr() as *const libc::iovec,
+                cmp::min(bufs.len(), max_iov()) as libc::c_int,
+                offset as _,
+            )
+        })?;
+        Ok(ret as usize)
+    }
+
+    // We support old MacOS and iOS versions that do not have `pwritev`. There is
+    // no `syscall` possible in these platform.
+    #[cfg(any(
+        all(target_os = "android", target_pointer_width = "32"),
+        target_os = "ios",
+        target_os = "macos",
+    ))]
+    pub fn write_vectored_at(&self, bufs: &[IoSlice<'_>], offset: u64) -> io::Result<usize> {
+        super::weak::weak!(fn pwritev64(libc::c_int, *const libc::iovec, libc::c_int, off64_t) -> isize);
+
+        match pwritev64.get() {
+            Some(pwritev) => {
+                let ret = cvt(unsafe {
+                    pwritev(
+                        self.as_raw_fd(),
+                        bufs.as_ptr() as *const libc::iovec,
+                        cmp::min(bufs.len(), max_iov()) as libc::c_int,
+                        offset as _,
+                    )
+                })?;
+                Ok(ret as usize)
+            }
+            None => io::default_write_vectored(|b| self.write_at(b, offset), bufs),
+        }
     }
 
     #[cfg(not(any(
@@ -212,7 +391,8 @@ impl FileDesc {
         target_os = "linux",
         target_os = "haiku",
         target_os = "redox",
-        target_os = "vxworks"
+        target_os = "vxworks",
+        target_os = "nto",
     )))]
     pub fn set_cloexec(&self) -> io::Result<()> {
         unsafe {
@@ -230,7 +410,8 @@ impl FileDesc {
         target_os = "linux",
         target_os = "haiku",
         target_os = "redox",
-        target_os = "vxworks"
+        target_os = "vxworks",
+        target_os = "nto",
     ))]
     pub fn set_cloexec(&self) -> io::Result<()> {
         unsafe {
@@ -284,6 +465,10 @@ impl<'a> Read for &'a FileDesc {
     fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
         (**self).read(buf)
     }
+
+    fn read_buf(&mut self, cursor: BorrowedCursor<'_>) -> io::Result<()> {
+        (**self).read_buf(cursor)
+    }
 }
 
 impl AsInner<OwnedFd> for FileDesc {
diff --git a/library/std/src/sys/unix/fs.rs b/library/std/src/sys/unix/fs.rs
index 8e1f35d6c..7566fafda 100644
--- a/library/std/src/sys/unix/fs.rs
+++ b/library/std/src/sys/unix/fs.rs
@@ -13,7 +13,8 @@ use crate::mem;
     target_os = "solaris",
     target_os = "fuchsia",
     target_os = "redox",
-    target_os = "illumos"
+    target_os = "illumos",
+    target_os = "nto",
 ))]
 use crate::mem::MaybeUninit;
 use crate::os::unix::io::{AsFd, AsRawFd, BorrowedFd, FromRawFd, IntoRawFd};
@@ -54,7 +55,8 @@ use libc::fstatat64;
     target_os = "solaris",
     target_os = "fuchsia",
     target_os = "redox",
-    target_os = "illumos"
+    target_os = "illumos",
+    target_os = "nto",
 ))]
 use libc::readdir as readdir64;
 #[cfg(target_os = "linux")]
@@ -69,7 +71,8 @@ use libc::readdir64_r;
     target_os = "illumos",
     target_os = "l4re",
     target_os = "fuchsia",
-    target_os = "redox"
+    target_os = "redox",
+    target_os = "nto",
 )))]
 use libc::readdir_r as readdir64_r;
 #[cfg(target_os = "android")]
@@ -277,7 +280,8 @@ unsafe impl Sync for Dir {}
     target_os = "solaris",
     target_os = "illumos",
     target_os = "fuchsia",
-    target_os = "redox"
+    target_os = "redox",
+    target_os = "nto",
 ))]
 pub struct DirEntry {
     dir: Arc<InnerReadDir>,
@@ -297,11 +301,12 @@ pub struct DirEntry {
     target_os = "solaris",
     target_os = "illumos",
     target_os = "fuchsia",
-    target_os = "redox"
+    target_os = "redox",
+    target_os = "nto",
 ))]
 struct dirent64_min {
     d_ino: u64,
-    #[cfg(not(any(target_os = "solaris", target_os = "illumos")))]
+    #[cfg(not(any(target_os = "solaris", target_os = "illumos", target_os = "nto")))]
     d_type: u8,
 }
 
@@ -311,7 +316,8 @@ struct dirent64_min {
     target_os = "solaris",
     target_os = "illumos",
     target_os = "fuchsia",
-    target_os = "redox"
+    target_os = "redox",
+    target_os = "nto",
 )))]
 pub struct DirEntry {
     dir: Arc<InnerReadDir>,
@@ -438,7 +444,7 @@ impl FileAttr {
     }
 }
 
-#[cfg(not(target_os = "netbsd"))]
+#[cfg(not(any(target_os = "netbsd", target_os = "nto")))]
 impl FileAttr {
     #[cfg(not(any(target_os = "vxworks", target_os = "espidf", target_os = "horizon")))]
     pub fn modified(&self) -> io::Result<SystemTime> {
@@ -524,6 +530,21 @@ impl FileAttr {
     }
 }
 
+#[cfg(target_os = "nto")]
+impl FileAttr {
+    pub fn modified(&self) -> io::Result<SystemTime> {
+        Ok(SystemTime::new(self.stat.st_mtim.tv_sec, self.stat.st_mtim.tv_nsec))
+    }
+
+    pub fn accessed(&self) -> io::Result<SystemTime> {
+        Ok(SystemTime::new(self.stat.st_atim.tv_sec, self.stat.st_atim.tv_nsec))
+    }
+
+    pub fn created(&self) -> io::Result<SystemTime> {
+        Ok(SystemTime::new(self.stat.st_ctim.tv_sec, self.stat.st_ctim.tv_nsec))
+    }
+}
+
 impl AsInner<stat64> for FileAttr {
     fn as_inner(&self) -> &stat64 {
         &self.stat
@@ -603,7 +624,8 @@ impl Iterator for ReadDir {
         target_os = "solaris",
         target_os = "fuchsia",
         target_os = "redox",
-        target_os = "illumos"
+        target_os = "illumos",
+        target_os = "nto",
     ))]
     fn next(&mut self) -> Option<io::Result<DirEntry>> {
         if self.end_of_stream {
@@ -686,7 +708,11 @@ impl Iterator for ReadDir {
 
                 let entry = dirent64_min {
                     d_ino: *offset_ptr!(entry_ptr, d_ino) as u64,
-                    #[cfg(not(any(target_os = "solaris", target_os = "illumos")))]
+                    #[cfg(not(any(
+                        target_os = "solaris",
+                        target_os = "illumos",
+                        target_os = "nto",
+                    )))]
                     d_type: *offset_ptr!(entry_ptr, d_type) as u8,
                 };
 
@@ -705,7 +731,8 @@ impl Iterator for ReadDir {
         target_os = "solaris",
         target_os = "fuchsia",
         target_os = "redox",
-        target_os = "illumos"
+        target_os = "illumos",
+        target_os = "nto",
     )))]
     fn next(&mut self) -> Option<io::Result<DirEntry>> {
         if self.end_of_stream {
@@ -794,7 +821,8 @@ impl DirEntry {
         target_os = "solaris",
         target_os = "illumos",
         target_os = "haiku",
-        target_os = "vxworks"
+        target_os = "vxworks",
+        target_os = "nto",
     ))]
     pub fn file_type(&self) -> io::Result<FileType> {
         self.metadata().map(|m| m.file_type())
@@ -804,7 +832,8 @@ impl DirEntry {
         target_os = "solaris",
         target_os = "illumos",
         target_os = "haiku",
-        target_os = "vxworks"
+        target_os = "vxworks",
+        target_os = "nto",
     )))]
     pub fn file_type(&self) -> io::Result<FileType> {
         match self.entry.d_type {
@@ -834,7 +863,8 @@ impl DirEntry {
         target_os = "redox",
         target_os = "vxworks",
         target_os = "espidf",
-        target_os = "horizon"
+        target_os = "horizon",
+        target_os = "nto",
     ))]
     pub fn ino(&self) -> u64 {
         self.entry.d_ino as u64
@@ -887,7 +917,8 @@ impl DirEntry {
         target_os = "solaris",
         target_os = "illumos",
         target_os = "fuchsia",
-        target_os = "redox"
+        target_os = "redox",
+        target_os = "nto",
     )))]
     fn name_cstr(&self) -> &CStr {
         unsafe { CStr::from_ptr(self.entry.d_name.as_ptr()) }
@@ -898,7 +929,8 @@ impl DirEntry {
         target_os = "solaris",
         target_os = "illumos",
         target_os = "fuchsia",
-        target_os = "redox"
+        target_os = "redox",
+        target_os = "nto",
     ))]
     fn name_cstr(&self) -> &CStr {
         &self.name
@@ -1051,7 +1083,8 @@ impl File {
             target_os = "linux",
             target_os = "android",
             target_os = "netbsd",
-            target_os = "openbsd"
+            target_os = "openbsd",
+            target_os = "nto",
         ))]
         unsafe fn os_datasync(fd: c_int) -> c_int {
             libc::fdatasync(fd)
@@ -1065,6 +1098,7 @@ impl File {
             target_os = "netbsd",
             target_os = "openbsd",
             target_os = "watchos",
+            target_os = "nto",
         )))]
         unsafe fn os_datasync(fd: c_int) -> c_int {
             libc::fsync(fd)
@@ -1098,6 +1132,10 @@ impl File {
         self.0.read_buf(cursor)
     }
 
+    pub fn read_vectored_at(&self, bufs: &mut [IoSliceMut<'_>], offset: u64) -> io::Result<usize> {
+        self.0.read_vectored_at(bufs, offset)
+    }
+
     pub fn write(&self, buf: &[u8]) -> io::Result<usize> {
         self.0.write(buf)
     }
@@ -1115,6 +1153,10 @@ impl File {
         self.0.write_at(buf, offset)
     }
 
+    pub fn write_vectored_at(&self, bufs: &[IoSlice<'_>], offset: u64) -> io::Result<usize> {
+        self.0.write_vectored_at(bufs, offset)
+    }
+
     pub fn flush(&self) -> io::Result<()> {
         Ok(())
     }
@@ -1750,13 +1792,25 @@ pub fn chroot(dir: &Path) -> io::Result<()> {
 pub use remove_dir_impl::remove_dir_all;
 
 // Fallback for REDOX, ESP-ID, Horizon, and Miri
-#[cfg(any(target_os = "redox", target_os = "espidf", target_os = "horizon", miri))]
+#[cfg(any(
+    target_os = "redox",
+    target_os = "espidf",
+    target_os = "horizon",
+    target_os = "nto",
+    miri
+))]
 mod remove_dir_impl {
     pub use crate::sys_common::fs::remove_dir_all;
 }
 
 // Modern implementation using openat(), unlinkat() and fdopendir()
-#[cfg(not(any(target_os = "redox", target_os = "espidf", target_os = "horizon", miri)))]
+#[cfg(not(any(
+    target_os = "redox",
+    target_os = "espidf",
+    target_os = "horizon",
+    target_os = "nto",
+    miri
+)))]
 mod remove_dir_impl {
     use super::{lstat, Dir, DirEntry, InnerReadDir, ReadDir};
     use crate::ffi::CStr;
diff --git a/library/std/src/sys/unix/locks/pthread_condvar.rs b/library/std/src/sys/unix/locks/pthread_condvar.rs
index 6be1abc2b..192fa216d 100644
--- a/library/std/src/sys/unix/locks/pthread_condvar.rs
+++ b/library/std/src/sys/unix/locks/pthread_condvar.rs
@@ -2,7 +2,10 @@ use crate::cell::UnsafeCell;
 use crate::ptr;
 use crate::sync::atomic::{AtomicPtr, Ordering::Relaxed};
 use crate::sys::locks::{pthread_mutex, Mutex};
+#[cfg(not(target_os = "nto"))]
 use crate::sys::time::TIMESPEC_MAX;
+#[cfg(target_os = "nto")]
+use crate::sys::time::TIMESPEC_MAX_CAPPED;
 use crate::sys_common::lazy_box::{LazyBox, LazyInit};
 use crate::time::Duration;
 
@@ -132,10 +135,18 @@ impl Condvar {
         let mutex = pthread_mutex::raw(mutex);
         self.verify(mutex);
 
+        #[cfg(not(target_os = "nto"))]
         let timeout = Timespec::now(libc::CLOCK_MONOTONIC)
             .checked_add_duration(&dur)
             .and_then(|t| t.to_timespec())
             .unwrap_or(TIMESPEC_MAX);
+
+        #[cfg(target_os = "nto")]
+        let timeout = Timespec::now(libc::CLOCK_MONOTONIC)
+            .checked_add_duration(&dur)
+            .and_then(|t| t.to_timespec_capped())
+            .unwrap_or(TIMESPEC_MAX_CAPPED);
+
         let r = libc::pthread_cond_timedwait(raw(self), mutex, &timeout);
         assert!(r == libc::ETIMEDOUT || r == 0);
         r == 0
diff --git a/library/std/src/sys/unix/mod.rs b/library/std/src/sys/unix/mod.rs
index 30a96be14..68c9520cc 100644
--- a/library/std/src/sys/unix/mod.rs
+++ b/library/std/src/sys/unix/mod.rs
@@ -329,7 +329,7 @@ pub fn cvt_nz(error: libc::c_int) -> crate::io::Result<()> {
 // do so.  In 1003.1-2004 this was fixed.
 //
 // glibc's implementation did the flush, unsafely, before glibc commit
-// 91e7cf982d01 `abort: Do not flush stdio streams [BZ #15436]' by Florian
+// 91e7cf982d01 `abort: Do not flush stdio streams [BZ #15436]` by Florian
 // Weimer.  According to glibc's NEWS:
 //
 //    The abort function terminates the process immediately, without flushing
diff --git a/library/std/src/sys/unix/net.rs b/library/std/src/sys/unix/net.rs
index c86f80972..8e05b618d 100644
--- a/library/std/src/sys/unix/net.rs
+++ b/library/std/src/sys/unix/net.rs
@@ -78,6 +78,7 @@ impl Socket {
                     target_os = "linux",
                     target_os = "netbsd",
                     target_os = "openbsd",
+                    target_os = "nto",
                 ))] {
                     // On platforms that support it we pass the SOCK_CLOEXEC
                     // flag to atomically create the socket and set it as
@@ -115,6 +116,7 @@ impl Socket {
                     target_os = "linux",
                     target_os = "netbsd",
                     target_os = "openbsd",
+                    target_os = "nto",
                 ))] {
                     // Like above, set cloexec atomically
                     cvt(libc::socketpair(fam, ty | libc::SOCK_CLOEXEC, 0, fds.as_mut_ptr()))?;
diff --git a/library/std/src/sys/unix/os.rs b/library/std/src/sys/unix/os.rs
index 2f2663db6..21b035fb3 100644
--- a/library/std/src/sys/unix/os.rs
+++ b/library/std/src/sys/unix/os.rs
@@ -62,6 +62,7 @@ extern "C" {
         link_name = "__errno"
     )]
     #[cfg_attr(any(target_os = "solaris", target_os = "illumos"), link_name = "___errno")]
+    #[cfg_attr(target_os = "nto", link_name = "__get_errno_ptr")]
     #[cfg_attr(
         any(target_os = "macos", target_os = "ios", target_os = "freebsd", target_os = "watchos"),
         link_name = "__error"
@@ -361,6 +362,17 @@ pub fn current_exe() -> io::Result<PathBuf> {
     }
 }
 
+#[cfg(target_os = "nto")]
+pub fn current_exe() -> io::Result<PathBuf> {
+    let mut e = crate::fs::read("/proc/self/exefile")?;
+    // Current versions of QNX Neutrino provide a null-terminated path.
+    // Ensure the trailing null byte is not returned here.
+    if let Some(0) = e.last() {
+        e.pop();
+    }
+    Ok(PathBuf::from(OsString::from_vec(e)))
+}
+
 #[cfg(any(target_os = "macos", target_os = "ios", target_os = "watchos"))]
 pub fn current_exe() -> io::Result<PathBuf> {
     unsafe {
diff --git a/library/std/src/sys/unix/process/process_unix.rs b/library/std/src/sys/unix/process/process_unix.rs
index 3bc17b775..ceaff5966 100644
--- a/library/std/src/sys/unix/process/process_unix.rs
+++ b/library/std/src/sys/unix/process/process_unix.rs
@@ -18,6 +18,7 @@ use crate::sys::weak::raw_syscall;
     target_os = "freebsd",
     all(target_os = "linux", target_env = "gnu"),
     all(target_os = "linux", target_env = "musl"),
+    target_os = "nto",
 ))]
 use crate::sys::weak::weak;
 
@@ -30,6 +31,15 @@ use libc::{c_int, pid_t};
 #[cfg(not(any(target_os = "vxworks", target_os = "l4re")))]
 use libc::{gid_t, uid_t};
 
+cfg_if::cfg_if! {
+    if #[cfg(all(target_os = "nto", target_env = "nto71"))] {
+        use crate::thread;
+        use libc::{c_char, posix_spawn_file_actions_t, posix_spawnattr_t};
+        // arbitrary number of tries:
+        const MAX_FORKSPAWN_TRIES: u32 = 4;
+    }
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 // Command
 ////////////////////////////////////////////////////////////////////////////////
@@ -140,11 +150,31 @@ impl Command {
 
     // Attempts to fork the process. If successful, returns Ok((0, -1))
     // in the child, and Ok((child_pid, -1)) in the parent.
-    #[cfg(not(target_os = "linux"))]
+    #[cfg(not(any(target_os = "linux", all(target_os = "nto", target_env = "nto71"))))]
     unsafe fn do_fork(&mut self) -> Result<(pid_t, pid_t), io::Error> {
         cvt(libc::fork()).map(|res| (res, -1))
     }
 
+    // On QNX Neutrino, fork can fail with EBADF in case "another thread might have opened
+    // or closed a file descriptor while the fork() was occurring".
+    // Documentation says "... or try calling fork() again". This is what we do here.
+    // See also https://www.qnx.com/developers/docs/7.1/#com.qnx.doc.neutrino.lib_ref/topic/f/fork.html
+    #[cfg(all(target_os = "nto", target_env = "nto71"))]
+    unsafe fn do_fork(&mut self) -> Result<(pid_t, pid_t), io::Error> {
+        use crate::sys::os::errno;
+
+        let mut tries_left = MAX_FORKSPAWN_TRIES;
+        loop {
+            let r = libc::fork();
+            if r == -1 as libc::pid_t && tries_left > 0 && errno() as libc::c_int == libc::EBADF {
+                thread::yield_now();
+                tries_left -= 1;
+            } else {
+                return cvt(r).map(|res| (res, -1));
+            }
+        }
+    }
+
     // Attempts to fork the process. If successful, returns Ok((0, -1))
     // in the child, and Ok((child_pid, child_pidfd)) in the parent.
     #[cfg(target_os = "linux")]
@@ -389,6 +419,7 @@ impl Command {
         target_os = "freebsd",
         all(target_os = "linux", target_env = "gnu"),
         all(target_os = "linux", target_env = "musl"),
+        target_os = "nto",
     )))]
     fn posix_spawn(
         &mut self,
@@ -405,6 +436,7 @@ impl Command {
         target_os = "freebsd",
         all(target_os = "linux", target_env = "gnu"),
         all(target_os = "linux", target_env = "musl"),
+        target_os = "nto",
     ))]
     fn posix_spawn(
         &mut self,
@@ -436,6 +468,34 @@ impl Command {
             }
         }
 
+        // On QNX Neutrino, posix_spawnp can fail with EBADF in case "another thread might have opened
+        // or closed a file descriptor while the posix_spawn() was occurring".
+        // Documentation says "... or try calling posix_spawn() again". This is what we do here.
+        // See also http://www.qnx.com/developers/docs/7.1/#com.qnx.doc.neutrino.lib_ref/topic/p/posix_spawn.html
+        #[cfg(all(target_os = "nto", target_env = "nto71"))]
+        unsafe fn retrying_libc_posix_spawnp(
+            pid: *mut pid_t,
+            file: *const c_char,
+            file_actions: *const posix_spawn_file_actions_t,
+            attrp: *const posix_spawnattr_t,
+            argv: *const *mut c_char,
+            envp: *const *mut c_char,
+        ) -> i32 {
+            let mut tries_left = MAX_FORKSPAWN_TRIES;
+            loop {
+                match libc::posix_spawnp(pid, file, file_actions, attrp, argv, envp) {
+                    libc::EBADF if tries_left > 0 => {
+                        thread::yield_now();
+                        tries_left -= 1;
+                        continue;
+                    }
+                    r => {
+                        return r;
+                    }
+                }
+            }
+        }
+
         // Solaris, glibc 2.29+, and musl 1.24+ can set a new working directory,
         // and maybe others will gain this non-POSIX function too. We'll check
         // for this weak symbol as soon as it's needed, so we can return early
@@ -555,7 +615,12 @@ impl Command {
             // Make sure we synchronize access to the global `environ` resource
             let _env_lock = sys::os::env_read_lock();
             let envp = envp.map(|c| c.as_ptr()).unwrap_or_else(|| *sys::os::environ() as *const _);
-            cvt_nz(libc::posix_spawnp(
+
+            #[cfg(not(target_os = "nto"))]
+            let spawn_fn = libc::posix_spawnp;
+            #[cfg(target_os = "nto")]
+            let spawn_fn = retrying_libc_posix_spawnp;
+            cvt_nz(spawn_fn(
                 &mut p.pid,
                 self.get_program_cstr().as_ptr(),
                 file_actions.0.as_ptr(),
@@ -760,7 +825,7 @@ fn signal_string(signal: i32) -> &'static str {
             )
         ))]
         libc::SIGSTKFLT => " (SIGSTKFLT)",
-        #[cfg(target_os = "linux")]
+        #[cfg(any(target_os = "linux", target_os = "nto"))]
         libc::SIGPWR => " (SIGPWR)",
         #[cfg(any(
             target_os = "macos",
@@ -769,7 +834,8 @@ fn signal_string(signal: i32) -> &'static str {
             target_os = "freebsd",
             target_os = "netbsd",
             target_os = "openbsd",
-            target_os = "dragonfly"
+            target_os = "dragonfly",
+            target_os = "nto",
         ))]
         libc::SIGEMT => " (SIGEMT)",
         #[cfg(any(
diff --git a/library/std/src/sys/unix/thread.rs b/library/std/src/sys/unix/thread.rs
index 2a1830d06..15070b1f6 100644
--- a/library/std/src/sys/unix/thread.rs
+++ b/library/std/src/sys/unix/thread.rs
@@ -9,7 +9,7 @@ use crate::time::Duration;
 
 #[cfg(all(target_os = "linux", target_env = "gnu"))]
 use crate::sys::weak::dlsym;
-#[cfg(any(target_os = "solaris", target_os = "illumos"))]
+#[cfg(any(target_os = "solaris", target_os = "illumos", target_os = "nto"))]
 use crate::sys::weak::weak;
 #[cfg(not(any(target_os = "l4re", target_os = "vxworks", target_os = "espidf")))]
 pub const DEFAULT_MIN_STACK_SIZE: usize = 2 * 1024 * 1024;
@@ -49,7 +49,7 @@ unsafe impl Sync for Thread {}
 impl Thread {
     // unsafe: see thread::Builder::spawn_unchecked for safety requirements
     pub unsafe fn new(stack: usize, p: Box<dyn FnOnce()>) -> io::Result<Thread> {
-        let p = Box::into_raw(box p);
+        let p = Box::into_raw(Box::new(p));
         let mut native: libc::pthread_t = mem::zeroed();
         let mut attr: libc::pthread_attr_t = mem::zeroed();
         assert_eq!(libc::pthread_attr_init(&mut attr), 0);
@@ -173,7 +173,7 @@ impl Thread {
         }
     }
 
-    #[cfg(any(target_os = "solaris", target_os = "illumos"))]
+    #[cfg(any(target_os = "solaris", target_os = "illumos", target_os = "nto"))]
     pub fn set_name(name: &CStr) {
         weak! {
             fn pthread_setname_np(
@@ -381,6 +381,17 @@ pub fn available_parallelism() -> io::Result<NonZeroUsize> {
             }
 
             Ok(unsafe { NonZeroUsize::new_unchecked(cpus as usize) })
+        } else if #[cfg(target_os = "nto")] {
+            unsafe {
+                use libc::_syspage_ptr;
+                if _syspage_ptr.is_null() {
+                    Err(io::const_io_error!(io::ErrorKind::NotFound, "No syspage available"))
+                } else {
+                    let cpus = (*_syspage_ptr).num_cpu;
+                    NonZeroUsize::new(cpus as usize)
+                        .ok_or(io::const_io_error!(io::ErrorKind::NotFound, "The number of hardware threads is not known for the target platform"))
+                }
+            }
         } else if #[cfg(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`
diff --git a/library/std/src/sys/unix/thread_local_dtor.rs b/library/std/src/sys/unix/thread_local_dtor.rs
index d7fd2130f..236d2f2ee 100644
--- a/library/std/src/sys/unix/thread_local_dtor.rs
+++ b/library/std/src/sys/unix/thread_local_dtor.rs
@@ -11,13 +11,7 @@
 // Note, however, that we run on lots older linuxes, as well as cross
 // compiling from a newer linux to an older linux, so we also have a
 // fallback implementation to use as well.
-#[cfg(any(
-    target_os = "linux",
-    target_os = "fuchsia",
-    target_os = "redox",
-    target_os = "emscripten"
-))]
-#[cfg_attr(target_family = "wasm", allow(unused))] // might remain unused depending on target details (e.g. wasm32-unknown-emscripten)
+#[cfg(any(target_os = "linux", target_os = "fuchsia", target_os = "redox"))]
 pub unsafe fn register_dtor(t: *mut u8, dtor: unsafe extern "C" fn(*mut u8)) {
     use crate::mem;
     use crate::sys_common::thread_local_dtor::register_dtor_fallback;
@@ -57,44 +51,40 @@ pub unsafe fn register_dtor(t: *mut u8, dtor: unsafe extern "C" fn(*mut u8)) {
 #[cfg(target_os = "macos")]
 pub unsafe fn register_dtor(t: *mut u8, dtor: unsafe extern "C" fn(*mut u8)) {
     use crate::cell::Cell;
+    use crate::mem;
     use crate::ptr;
 
     #[thread_local]
     static REGISTERED: Cell<bool> = Cell::new(false);
+
+    #[thread_local]
+    static mut DTORS: Vec<(*mut u8, unsafe extern "C" fn(*mut u8))> = Vec::new();
+
     if !REGISTERED.get() {
         _tlv_atexit(run_dtors, ptr::null_mut());
         REGISTERED.set(true);
     }
 
-    type List = Vec<(*mut u8, unsafe extern "C" fn(*mut u8))>;
-
-    #[thread_local]
-    static DTORS: Cell<*mut List> = Cell::new(ptr::null_mut());
-    if DTORS.get().is_null() {
-        let v: Box<List> = box Vec::new();
-        DTORS.set(Box::into_raw(v));
-    }
-
     extern "C" {
         fn _tlv_atexit(dtor: unsafe extern "C" fn(*mut u8), arg: *mut u8);
     }
 
-    let list: &mut List = &mut *DTORS.get();
+    let list = &mut DTORS;
     list.push((t, dtor));
 
     unsafe extern "C" fn run_dtors(_: *mut u8) {
-        let mut ptr = DTORS.replace(ptr::null_mut());
-        while !ptr.is_null() {
-            let list = Box::from_raw(ptr);
-            for (ptr, dtor) in list.into_iter() {
+        let mut list = mem::take(&mut DTORS);
+        while !list.is_empty() {
+            for (ptr, dtor) in list {
                 dtor(ptr);
             }
-            ptr = DTORS.replace(ptr::null_mut());
+            list = mem::take(&mut DTORS);
         }
     }
 }
 
-#[cfg(any(target_os = "vxworks", target_os = "horizon"))]
+#[cfg(any(target_os = "vxworks", target_os = "horizon", target_os = "emscripten"))]
+#[cfg_attr(target_family = "wasm", allow(unused))] // might remain unused depending on target details (e.g. wasm32-unknown-emscripten)
 pub unsafe fn register_dtor(t: *mut u8, dtor: unsafe extern "C" fn(*mut u8)) {
     use crate::sys_common::thread_local_dtor::register_dtor_fallback;
     register_dtor_fallback(t, dtor);
diff --git a/library/std/src/sys/unix/thread_parking/pthread.rs b/library/std/src/sys/unix/thread_parking/pthread.rs
index 082d25e68..43046ed07 100644
--- a/library/std/src/sys/unix/thread_parking/pthread.rs
+++ b/library/std/src/sys/unix/thread_parking/pthread.rs
@@ -6,7 +6,10 @@ use crate::pin::Pin;
 use crate::ptr::addr_of_mut;
 use crate::sync::atomic::AtomicUsize;
 use crate::sync::atomic::Ordering::SeqCst;
+#[cfg(not(target_os = "nto"))]
 use crate::sys::time::TIMESPEC_MAX;
+#[cfg(target_os = "nto")]
+use crate::sys::time::TIMESPEC_MAX_CAPPED;
 use crate::time::Duration;
 
 const EMPTY: usize = 0;
@@ -80,8 +83,14 @@ unsafe fn wait_timeout(
         (Timespec::now(libc::CLOCK_MONOTONIC), dur)
     };
 
+    #[cfg(not(target_os = "nto"))]
     let timeout =
         now.checked_add_duration(&dur).and_then(|t| t.to_timespec()).unwrap_or(TIMESPEC_MAX);
+    #[cfg(target_os = "nto")]
+    let timeout = now
+        .checked_add_duration(&dur)
+        .and_then(|t| t.to_timespec_capped())
+        .unwrap_or(TIMESPEC_MAX_CAPPED);
     let r = libc::pthread_cond_timedwait(cond, lock, &timeout);
     debug_assert!(r == libc::ETIMEDOUT || r == 0);
 }
diff --git a/library/std/src/sys/unix/time.rs b/library/std/src/sys/unix/time.rs
index 2daad981b..0f11de8f5 100644
--- a/library/std/src/sys/unix/time.rs
+++ b/library/std/src/sys/unix/time.rs
@@ -9,6 +9,14 @@ pub const UNIX_EPOCH: SystemTime = SystemTime { t: Timespec::zero() };
 pub const TIMESPEC_MAX: libc::timespec =
     libc::timespec { tv_sec: <libc::time_t>::MAX, tv_nsec: 1_000_000_000 - 1 };
 
+// This additional constant is only used when calling
+// `libc::pthread_cond_timedwait`.
+#[cfg(target_os = "nto")]
+pub(super) const TIMESPEC_MAX_CAPPED: libc::timespec = libc::timespec {
+    tv_sec: (u64::MAX / NSEC_PER_SEC) as i64,
+    tv_nsec: (u64::MAX % NSEC_PER_SEC) as i64,
+};
+
 #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
 #[repr(transparent)]
 #[rustc_layout_scalar_valid_range_start(0)]
@@ -144,6 +152,20 @@ impl Timespec {
             tv_nsec: self.tv_nsec.0.try_into().ok()?,
         })
     }
+
+    // On QNX Neutrino, the maximum timespec for e.g. pthread_cond_timedwait
+    // is 2^64 nanoseconds
+    #[cfg(target_os = "nto")]
+    pub(super) fn to_timespec_capped(&self) -> Option<libc::timespec> {
+        // Check if timeout in nanoseconds would fit into an u64
+        if (self.tv_nsec.0 as u64)
+            .checked_add((self.tv_sec as u64).checked_mul(NSEC_PER_SEC)?)
+            .is_none()
+        {
+            return None;
+        }
+        self.to_timespec()
+    }
 }
 
 impl From<libc::timespec> for Timespec {
diff --git a/library/std/src/sys/unsupported/once.rs b/library/std/src/sys/unsupported/once.rs
index b4bb4975f..11fde1888 100644
--- a/library/std/src/sys/unsupported/once.rs
+++ b/library/std/src/sys/unsupported/once.rs
@@ -1,5 +1,6 @@
 use crate::cell::Cell;
 use crate::sync as public;
+use crate::sync::once::ExclusiveState;
 
 pub struct Once {
     state: Cell<State>,
@@ -44,6 +45,16 @@ impl Once {
         self.state.get() == State::Complete
     }
 
+    #[inline]
+    pub(crate) fn state(&mut self) -> ExclusiveState {
+        match self.state.get() {
+            State::Incomplete => ExclusiveState::Incomplete,
+            State::Poisoned => ExclusiveState::Poisoned,
+            State::Complete => ExclusiveState::Complete,
+            _ => unreachable!("invalid Once state"),
+        }
+    }
+
     #[cold]
     #[track_caller]
     pub fn call(&self, ignore_poisoning: bool, f: &mut impl FnMut(&public::OnceState)) {
diff --git a/library/std/src/sys/wasi/os.rs b/library/std/src/sys/wasi/os.rs
index f5513e999..9919dc708 100644
--- a/library/std/src/sys/wasi/os.rs
+++ b/library/std/src/sys/wasi/os.rs
@@ -21,6 +21,7 @@ mod libc {
     extern "C" {
         pub fn getcwd(buf: *mut c_char, size: size_t) -> *mut c_char;
         pub fn chdir(dir: *const c_char) -> c_int;
+        pub fn __wasilibc_get_environ() -> *mut *mut c_char;
     }
 }
 
@@ -161,7 +162,12 @@ impl Iterator for Env {
 pub fn env() -> Env {
     unsafe {
         let _guard = env_read_lock();
-        let mut environ = libc::environ;
+
+        // Use `__wasilibc_get_environ` instead of `environ` here so that we
+        // don't require wasi-libc to eagerly initialize the environment
+        // variables.
+        let mut environ = libc::__wasilibc_get_environ();
+
         let mut result = Vec::new();
         if !environ.is_null() {
             while !(*environ).is_null() {
diff --git a/library/std/src/sys/windows/args.rs b/library/std/src/sys/windows/args.rs
index 6741ae46d..30356fa85 100644
--- a/library/std/src/sys/windows/args.rs
+++ b/library/std/src/sys/windows/args.rs
@@ -270,7 +270,7 @@ pub(crate) fn make_bat_command_line(
     // It is necessary to surround the command in an extra pair of quotes,
     // hence the trailing quote here. It will be closed after all arguments
     // have been added.
-    let mut cmd: Vec<u16> = "cmd.exe /c \"".encode_utf16().collect();
+    let mut cmd: Vec<u16> = "cmd.exe /d /c \"".encode_utf16().collect();
 
     // Push the script name surrounded by its quote pair.
     cmd.push(b'"' as u16);
@@ -290,6 +290,15 @@ pub(crate) fn make_bat_command_line(
     // reconstructed by the batch script by default.
     for arg in args {
         cmd.push(' ' as u16);
+        // Make sure to always quote special command prompt characters, including:
+        // * Characters `cmd /?` says require quotes.
+        // * `%` for environment variables, as in `%TMP%`.
+        // * `|<>` pipe/redirect characters.
+        const SPECIAL: &[u8] = b"\t &()[]{}^=;!'+,`~%|<>";
+        let force_quotes = match arg {
+            Arg::Regular(arg) if !force_quotes => arg.bytes().iter().any(|c| SPECIAL.contains(c)),
+            _ => force_quotes,
+        };
         append_arg(&mut cmd, arg, force_quotes)?;
     }
 
diff --git a/library/std/src/sys/windows/c.rs b/library/std/src/sys/windows/c.rs
index f58dcf128..5d150eca0 100644
--- a/library/std/src/sys/windows/c.rs
+++ b/library/std/src/sys/windows/c.rs
@@ -6,13 +6,15 @@
 
 use crate::ffi::CStr;
 use crate::mem;
-use crate::os::raw::{c_char, c_int, c_long, c_longlong, c_uint, c_ulong, c_ushort};
+use crate::os::raw::{c_char, c_long, c_longlong, c_uint, c_ulong, c_ushort};
 use crate::os::windows::io::{BorrowedHandle, HandleOrInvalid, HandleOrNull};
 use crate::ptr;
 use core::ffi::NonZero_c_ulong;
 
 use libc::{c_void, size_t, wchar_t};
 
+pub use crate::os::raw::c_int;
+
 #[path = "c/errors.rs"] // c.rs is included from two places so we need to specify this
 mod errors;
 pub use errors::*;
@@ -47,16 +49,19 @@ pub type ACCESS_MASK = DWORD;
 
 pub type LPBOOL = *mut BOOL;
 pub type LPBYTE = *mut BYTE;
+pub type LPCCH = *const CHAR;
 pub type LPCSTR = *const CHAR;
+pub type LPCWCH = *const WCHAR;
 pub type LPCWSTR = *const WCHAR;
+pub type LPCVOID = *const c_void;
 pub type LPDWORD = *mut DWORD;
 pub type LPHANDLE = *mut HANDLE;
 pub type LPOVERLAPPED = *mut OVERLAPPED;
 pub type LPPROCESS_INFORMATION = *mut PROCESS_INFORMATION;
 pub type LPSECURITY_ATTRIBUTES = *mut SECURITY_ATTRIBUTES;
 pub type LPSTARTUPINFO = *mut STARTUPINFO;
+pub type LPSTR = *mut CHAR;
 pub type LPVOID = *mut c_void;
-pub type LPCVOID = *const c_void;
 pub type LPWCH = *mut WCHAR;
 pub type LPWIN32_FIND_DATAW = *mut WIN32_FIND_DATAW;
 pub type LPWSADATA = *mut WSADATA;
@@ -132,6 +137,10 @@ pub const MAX_PATH: usize = 260;
 
 pub const FILE_TYPE_PIPE: u32 = 3;
 
+pub const CP_UTF8: DWORD = 65001;
+pub const MB_ERR_INVALID_CHARS: DWORD = 0x08;
+pub const WC_ERR_INVALID_CHARS: DWORD = 0x80;
+
 #[repr(C)]
 #[derive(Copy)]
 pub struct WIN32_FIND_DATAW {
@@ -539,14 +548,6 @@ pub struct SYMBOLIC_LINK_REPARSE_BUFFER {
     pub PathBuffer: WCHAR,
 }
 
-/// NB: Use carefully! In general using this as a reference is likely to get the
-/// provenance wrong for the `PathBuffer` field!
-#[repr(C)]
-pub struct FILE_NAME_INFO {
-    pub FileNameLength: DWORD,
-    pub FileName: [WCHAR; 1],
-}
-
 #[repr(C)]
 pub struct MOUNT_POINT_REPARSE_BUFFER {
     pub SubstituteNameOffset: c_ushort,
@@ -1155,6 +1156,25 @@ extern "system" {
         lpFilePart: *mut LPWSTR,
     ) -> DWORD;
     pub fn GetFileAttributesW(lpFileName: LPCWSTR) -> DWORD;
+
+    pub fn MultiByteToWideChar(
+        CodePage: UINT,
+        dwFlags: DWORD,
+        lpMultiByteStr: LPCCH,
+        cbMultiByte: c_int,
+        lpWideCharStr: LPWSTR,
+        cchWideChar: c_int,
+    ) -> c_int;
+    pub fn WideCharToMultiByte(
+        CodePage: UINT,
+        dwFlags: DWORD,
+        lpWideCharStr: LPCWCH,
+        cchWideChar: c_int,
+        lpMultiByteStr: LPSTR,
+        cbMultiByte: c_int,
+        lpDefaultChar: LPCCH,
+        lpUsedDefaultChar: LPBOOL,
+    ) -> c_int;
 }
 
 #[link(name = "ws2_32")]
diff --git a/library/std/src/sys/windows/fs.rs b/library/std/src/sys/windows/fs.rs
index 378098038..d2c597664 100644
--- a/library/std/src/sys/windows/fs.rs
+++ b/library/std/src/sys/windows/fs.rs
@@ -1266,7 +1266,12 @@ fn metadata(path: &Path, reparse: ReparsePoint) -> io::Result<FileAttr> {
     // If the fallback fails for any reason we return the original error.
     match File::open(path, &opts) {
         Ok(file) => file.file_attr(),
-        Err(e) if e.raw_os_error() == Some(c::ERROR_SHARING_VIOLATION as _) => {
+        Err(e)
+            if [Some(c::ERROR_SHARING_VIOLATION as _), Some(c::ERROR_ACCESS_DENIED as _)]
+                .contains(&e.raw_os_error()) =>
+        {
+            // `ERROR_ACCESS_DENIED` is returned when the user doesn't have permission for the resource.
+            // One such example is `System Volume Information` as default but can be created as well
             // `ERROR_SHARING_VIOLATION` will almost never be returned.
             // Usually if a file is locked you can still read some metadata.
             // However, there are special system files, such as
@@ -1393,6 +1398,8 @@ fn symlink_junction_inner(original: &Path, junction: &Path) -> io::Result<()> {
         let mut data = Align8([MaybeUninit::<u8>::uninit(); c::MAXIMUM_REPARSE_DATA_BUFFER_SIZE]);
         let data_ptr = data.0.as_mut_ptr();
         let db = data_ptr.cast::<c::REPARSE_MOUNTPOINT_DATA_BUFFER>();
+        // Zero the header to ensure it's fully initialized, including reserved parameters.
+        *db = mem::zeroed();
         let buf = ptr::addr_of_mut!((*db).ReparseTarget).cast::<c::WCHAR>();
         let mut i = 0;
         // FIXME: this conversion is very hacky
diff --git a/library/std/src/sys/windows/io.rs b/library/std/src/sys/windows/io.rs
index 2cc34c986..7fdd1f702 100644
--- a/library/std/src/sys/windows/io.rs
+++ b/library/std/src/sys/windows/io.rs
@@ -2,8 +2,7 @@ use crate::marker::PhantomData;
 use crate::mem::size_of;
 use crate::os::windows::io::{AsHandle, AsRawHandle, BorrowedHandle};
 use crate::slice;
-use crate::sys::{c, Align8};
-use core;
+use crate::sys::c;
 use libc;
 
 #[derive(Copy, Clone)]
@@ -125,22 +124,33 @@ unsafe fn msys_tty_on(handle: c::HANDLE) -> bool {
         return false;
     }
 
-    const SIZE: usize = size_of::<c::FILE_NAME_INFO>() + c::MAX_PATH * size_of::<c::WCHAR>();
-    let mut name_info_bytes = Align8([0u8; SIZE]);
+    /// Mirrors [`FILE_NAME_INFO`], giving it a fixed length that we can stack
+    /// allocate
+    ///
+    /// [`FILE_NAME_INFO`]: https://learn.microsoft.com/en-us/windows/win32/api/winbase/ns-winbase-file_name_info
+    #[repr(C)]
+    #[allow(non_snake_case)]
+    struct FILE_NAME_INFO {
+        FileNameLength: u32,
+        FileName: [u16; c::MAX_PATH as usize],
+    }
+    let mut name_info = FILE_NAME_INFO { FileNameLength: 0, FileName: [0; c::MAX_PATH as usize] };
+    // Safety: buffer length is fixed.
     let res = c::GetFileInformationByHandleEx(
         handle,
         c::FileNameInfo,
-        name_info_bytes.0.as_mut_ptr() as *mut libc::c_void,
-        SIZE as u32,
+        &mut name_info as *mut _ as *mut libc::c_void,
+        size_of::<FILE_NAME_INFO>() as u32,
     );
     if res == 0 {
         return false;
     }
-    let name_info: &c::FILE_NAME_INFO = &*(name_info_bytes.0.as_ptr() as *const c::FILE_NAME_INFO);
-    let name_len = name_info.FileNameLength as usize / 2;
-    // Offset to get the `FileName` field.
-    let name_ptr = name_info_bytes.0.as_ptr().offset(size_of::<c::DWORD>() as isize).cast::<u16>();
-    let s = core::slice::from_raw_parts(name_ptr, name_len);
+
+    // Use `get` because `FileNameLength` can be out of range.
+    let s = match name_info.FileName.get(..name_info.FileNameLength as usize / 2) {
+        None => return false,
+        Some(s) => s,
+    };
     let name = String::from_utf16_lossy(s);
     // Get the file name only.
     let name = name.rsplit('\\').next().unwrap_or(&name);
diff --git a/library/std/src/sys/windows/stdio.rs b/library/std/src/sys/windows/stdio.rs
index 70c9b14a0..32c6ccffb 100644
--- a/library/std/src/sys/windows/stdio.rs
+++ b/library/std/src/sys/windows/stdio.rs
@@ -1,6 +1,5 @@
 #![unstable(issue = "none", feature = "windows_stdio")]
 
-use crate::char::decode_utf16;
 use crate::cmp;
 use crate::io;
 use crate::mem::MaybeUninit;
@@ -170,14 +169,27 @@ fn write(
 }
 
 fn write_valid_utf8_to_console(handle: c::HANDLE, utf8: &str) -> io::Result<usize> {
+    debug_assert!(!utf8.is_empty());
+
     let mut utf16 = [MaybeUninit::<u16>::uninit(); MAX_BUFFER_SIZE / 2];
-    let mut len_utf16 = 0;
-    for (chr, dest) in utf8.encode_utf16().zip(utf16.iter_mut()) {
-        *dest = MaybeUninit::new(chr);
-        len_utf16 += 1;
-    }
-    // Safety: We've initialized `len_utf16` values.
-    let utf16: &[u16] = unsafe { MaybeUninit::slice_assume_init_ref(&utf16[..len_utf16]) };
+    let utf8 = &utf8[..utf8.floor_char_boundary(utf16.len())];
+
+    let utf16: &[u16] = unsafe {
+        // Note that this theoretically checks validity twice in the (most common) case
+        // where the underlying byte sequence is valid utf-8 (given the check in `write()`).
+        let result = c::MultiByteToWideChar(
+            c::CP_UTF8,                      // CodePage
+            c::MB_ERR_INVALID_CHARS,         // dwFlags
+            utf8.as_ptr() as c::LPCCH,       // lpMultiByteStr
+            utf8.len() as c::c_int,          // cbMultiByte
+            utf16.as_mut_ptr() as c::LPWSTR, // lpWideCharStr
+            utf16.len() as c::c_int,         // cchWideChar
+        );
+        assert!(result != 0, "Unexpected error in MultiByteToWideChar");
+
+        // Safety: MultiByteToWideChar initializes `result` values.
+        MaybeUninit::slice_assume_init_ref(&utf16[..result as usize])
+    };
 
     let mut written = write_u16s(handle, &utf16)?;
 
@@ -190,8 +202,8 @@ fn write_valid_utf8_to_console(handle: c::HANDLE, utf8: &str) -> io::Result<usiz
         // a missing surrogate can be produced (and also because of the UTF-8 validation above),
         // write the missing surrogate out now.
         // Buffering it would mean we have to lie about the number of bytes written.
-        let first_char_remaining = utf16[written];
-        if first_char_remaining >= 0xDCEE && first_char_remaining <= 0xDFFF {
+        let first_code_unit_remaining = utf16[written];
+        if first_code_unit_remaining >= 0xDCEE && first_code_unit_remaining <= 0xDFFF {
             // low surrogate
             // We just hope this works, and give up otherwise
             let _ = write_u16s(handle, &utf16[written..written + 1]);
@@ -213,6 +225,7 @@ fn write_valid_utf8_to_console(handle: c::HANDLE, utf8: &str) -> io::Result<usiz
 }
 
 fn write_u16s(handle: c::HANDLE, data: &[u16]) -> io::Result<usize> {
+    debug_assert!(data.len() < u32::MAX as usize);
     let mut written = 0;
     cvt(unsafe {
         c::WriteConsoleW(
@@ -366,26 +379,32 @@ fn read_u16s(handle: c::HANDLE, buf: &mut [MaybeUninit<u16>]) -> io::Result<usiz
     Ok(amount as usize)
 }
 
-#[allow(unused)]
 fn utf16_to_utf8(utf16: &[u16], utf8: &mut [u8]) -> io::Result<usize> {
-    let mut written = 0;
-    for chr in decode_utf16(utf16.iter().cloned()) {
-        match chr {
-            Ok(chr) => {
-                chr.encode_utf8(&mut utf8[written..]);
-                written += chr.len_utf8();
-            }
-            Err(_) => {
-                // We can't really do any better than forget all data and return an error.
-                return Err(io::const_io_error!(
-                    io::ErrorKind::InvalidData,
-                    "Windows stdin in console mode does not support non-UTF-16 input; \
-                     encountered unpaired surrogate",
-                ));
-            }
-        }
+    debug_assert!(utf16.len() <= c::c_int::MAX as usize);
+    debug_assert!(utf8.len() <= c::c_int::MAX as usize);
+
+    let result = unsafe {
+        c::WideCharToMultiByte(
+            c::CP_UTF8,                    // CodePage
+            c::WC_ERR_INVALID_CHARS,       // dwFlags
+            utf16.as_ptr(),                // lpWideCharStr
+            utf16.len() as c::c_int,       // cchWideChar
+            utf8.as_mut_ptr() as c::LPSTR, // lpMultiByteStr
+            utf8.len() as c::c_int,        // cbMultiByte
+            ptr::null(),                   // lpDefaultChar
+            ptr::null_mut(),               // lpUsedDefaultChar
+        )
+    };
+    if result == 0 {
+        // We can't really do any better than forget all data and return an error.
+        Err(io::const_io_error!(
+            io::ErrorKind::InvalidData,
+            "Windows stdin in console mode does not support non-UTF-16 input; \
+            encountered unpaired surrogate",
+        ))
+    } else {
+        Ok(result as usize)
     }
-    Ok(written)
 }
 
 impl IncompleteUtf8 {
diff --git a/library/std/src/sys/windows/thread.rs b/library/std/src/sys/windows/thread.rs
index 1cb576c95..ed58c47e0 100644
--- a/library/std/src/sys/windows/thread.rs
+++ b/library/std/src/sys/windows/thread.rs
@@ -22,7 +22,7 @@ pub struct Thread {
 impl Thread {
     // unsafe: see thread::Builder::spawn_unchecked for safety requirements
     pub unsafe fn new(stack: usize, p: Box<dyn FnOnce()>) -> io::Result<Thread> {
-        let p = Box::into_raw(box p);
+        let p = Box::into_raw(Box::new(p));
 
         // FIXME On UNIX, we guard against stack sizes that are too small but
         // that's because pthreads enforces that stacks are at least
diff --git a/library/std/src/sys/windows/thread_parking.rs b/library/std/src/sys/windows/thread_parking.rs
index 5d43676ad..eb9167cd8 100644
--- a/library/std/src/sys/windows/thread_parking.rs
+++ b/library/std/src/sys/windows/thread_parking.rs
@@ -221,7 +221,7 @@ impl Parker {
 
 fn keyed_event_handle() -> c::HANDLE {
     const INVALID: c::HANDLE = ptr::invalid_mut(!0);
-    static HANDLE: AtomicPtr<libc::c_void> = AtomicPtr::new(INVALID);
+    static HANDLE: AtomicPtr<crate::ffi::c_void> = AtomicPtr::new(INVALID);
     match HANDLE.load(Relaxed) {
         INVALID => {
             let mut handle = c::INVALID_HANDLE_VALUE;