Auto merge of #133527 - matthiaskrgr:rollup-kyre1df, r=matthiaskrgr

Rollup of 6 pull requests

Successful merges:

 - #132979 (use `--exact` on `--skip` to avoid unintended substring matches)
 - #133248 (CI: split x86_64-msvc-ext job)
 - #133449 (std: expose `const_io_error!` as `const_error!`)
 - #133453 (Commit license-metadata.json to git and check it's correct in CI)
 - #133457 (miri: implement `TlsFree`)
 - #133493 (do not constrain infer vars in `find_best_leaf_obligation`)

r? `@ghost`
`@rustbot` modify labels: rollup

79 files changed, 752 insertions, 434 deletions

diff --git a/REUSE.toml b/REUSE.toml
index 3a11c37854e..6b16d97ed80 100644
--- a/REUSE.toml
+++ b/REUSE.toml
@@ -28,6 +28,7 @@ path = [
     "COPYRIGHT",
     "INSTALL.md",
     "LICENSE-APACHE",
+    "license-metadata.json",
     "LICENSE-MIT",
     "README.md",
     "RELEASES.md",
diff --git a/compiler/rustc_trait_selection/src/solve/fulfill.rs b/compiler/rustc_trait_selection/src/solve/fulfill.rs
index 311dc214de6..0f90c45d032 100644
--- a/compiler/rustc_trait_selection/src/solve/fulfill.rs
+++ b/compiler/rustc_trait_selection/src/solve/fulfill.rs
@@ -346,12 +346,21 @@ fn find_best_leaf_obligation<'tcx>(
     consider_ambiguities: bool,
 ) -> PredicateObligation<'tcx> {
     let obligation = infcx.resolve_vars_if_possible(obligation.clone());
+    // FIXME: we use a probe here as the `BestObligation` visitor does not
+    // check whether it uses candidates which get shadowed by where-bounds.
+    //
+    // We should probably fix the visitor to not do so instead, as this also
+    // means the leaf obligation may be incorrect.
     infcx
-        .visit_proof_tree(obligation.clone().into(), &mut BestObligation {
-            obligation: obligation.clone(),
-            consider_ambiguities,
+        .fudge_inference_if_ok(|| {
+            infcx
+                .visit_proof_tree(obligation.clone().into(), &mut BestObligation {
+                    obligation: obligation.clone(),
+                    consider_ambiguities,
+                })
+                .break_value()
+                .ok_or(())
         })
-        .break_value()
         .unwrap_or(obligation)
 }
 
diff --git a/library/std/src/fs.rs b/library/std/src/fs.rs
index d846a4e5f09..2d5d869630e 100644
--- a/library/std/src/fs.rs
+++ b/library/std/src/fs.rs
@@ -3020,7 +3020,7 @@ impl DirBuilder {
         match path.parent() {
             Some(p) => self.create_dir_all(p)?,
             None => {
-                return Err(io::const_io_error!(
+                return Err(io::const_error!(
                     io::ErrorKind::Uncategorized,
                     "failed to create whole tree",
                 ));
diff --git a/library/std/src/io/buffered/bufreader/buffer.rs b/library/std/src/io/buffered/bufreader/buffer.rs
index 52fe49985c6..17721090db5 100644
--- a/library/std/src/io/buffered/bufreader/buffer.rs
+++ b/library/std/src/io/buffered/bufreader/buffer.rs
@@ -41,7 +41,7 @@ impl Buffer {
         match Box::try_new_uninit_slice(capacity) {
             Ok(buf) => Ok(Self { buf, pos: 0, filled: 0, initialized: 0 }),
             Err(_) => {
-                Err(io::const_io_error!(ErrorKind::OutOfMemory, "failed to allocate read buffer"))
+                Err(io::const_error!(ErrorKind::OutOfMemory, "failed to allocate read buffer"))
             }
         }
     }
diff --git a/library/std/src/io/buffered/bufwriter.rs b/library/std/src/io/buffered/bufwriter.rs
index c41bae2aa4e..574eb83dc56 100644
--- a/library/std/src/io/buffered/bufwriter.rs
+++ b/library/std/src/io/buffered/bufwriter.rs
@@ -96,7 +96,7 @@ impl<W: Write> BufWriter<W> {
 
     pub(crate) fn try_new_buffer() -> io::Result<Vec<u8>> {
         Vec::try_with_capacity(DEFAULT_BUF_SIZE).map_err(|_| {
-            io::const_io_error!(ErrorKind::OutOfMemory, "failed to allocate write buffer")
+            io::const_error!(ErrorKind::OutOfMemory, "failed to allocate write buffer")
         })
     }
 
@@ -238,7 +238,7 @@ impl<W: ?Sized + Write> BufWriter<W> {
 
             match r {
                 Ok(0) => {
-                    return Err(io::const_io_error!(
+                    return Err(io::const_error!(
                         ErrorKind::WriteZero,
                         "failed to write the buffered data",
                     ));
diff --git a/library/std/src/io/cursor.rs b/library/std/src/io/cursor.rs
index fbfdb4fa023..b2ffeb0f95d 100644
--- a/library/std/src/io/cursor.rs
+++ b/library/std/src/io/cursor.rs
@@ -304,7 +304,7 @@ where
                 self.pos = n;
                 Ok(self.pos)
             }
-            None => Err(io::const_io_error!(
+            None => Err(io::const_error!(
                 ErrorKind::InvalidInput,
                 "invalid seek to a negative or overflowing position",
             )),
@@ -446,7 +446,7 @@ fn reserve_and_pad<A: Allocator>(
     buf_len: usize,
 ) -> io::Result<usize> {
     let pos: usize = (*pos_mut).try_into().map_err(|_| {
-        io::const_io_error!(
+        io::const_error!(
             ErrorKind::InvalidInput,
             "cursor position exceeds maximum possible vector length",
         )
diff --git a/library/std/src/io/error.rs b/library/std/src/io/error.rs
index 5d7adcace52..03f38e220a5 100644
--- a/library/std/src/io/error.rs
+++ b/library/std/src/io/error.rs
@@ -76,31 +76,31 @@ impl fmt::Debug for Error {
 #[allow(dead_code)]
 impl Error {
     pub(crate) const INVALID_UTF8: Self =
-        const_io_error!(ErrorKind::InvalidData, "stream did not contain valid UTF-8");
+        const_error!(ErrorKind::InvalidData, "stream did not contain valid UTF-8");
 
     pub(crate) const READ_EXACT_EOF: Self =
-        const_io_error!(ErrorKind::UnexpectedEof, "failed to fill whole buffer");
+        const_error!(ErrorKind::UnexpectedEof, "failed to fill whole buffer");
 
-    pub(crate) const UNKNOWN_THREAD_COUNT: Self = const_io_error!(
+    pub(crate) const UNKNOWN_THREAD_COUNT: Self = const_error!(
         ErrorKind::NotFound,
         "The number of hardware threads is not known for the target platform"
     );
 
     pub(crate) const UNSUPPORTED_PLATFORM: Self =
-        const_io_error!(ErrorKind::Unsupported, "operation not supported on this platform");
+        const_error!(ErrorKind::Unsupported, "operation not supported on this platform");
 
     pub(crate) const WRITE_ALL_EOF: Self =
-        const_io_error!(ErrorKind::WriteZero, "failed to write whole buffer");
+        const_error!(ErrorKind::WriteZero, "failed to write whole buffer");
 
     pub(crate) const ZERO_TIMEOUT: Self =
-        const_io_error!(ErrorKind::InvalidInput, "cannot set a 0 duration timeout");
+        const_error!(ErrorKind::InvalidInput, "cannot set a 0 duration timeout");
 }
 
 #[stable(feature = "rust1", since = "1.0.0")]
 impl From<alloc::ffi::NulError> for Error {
     /// Converts a [`alloc::ffi::NulError`] into a [`Error`].
     fn from(_: alloc::ffi::NulError) -> Error {
-        const_io_error!(ErrorKind::InvalidInput, "data provided contains a nul byte")
+        const_error!(ErrorKind::InvalidInput, "data provided contains a nul byte")
     }
 }
 
@@ -151,27 +151,38 @@ pub type RawOsError = sys::RawOsError;
 // (For the sake of being explicit: the alignment requirement here only matters
 // if `error/repr_bitpacked.rs` is in use — for the unpacked repr it doesn't
 // matter at all)
+#[doc(hidden)]
+#[unstable(feature = "io_const_error_internals", issue = "none")]
 #[repr(align(4))]
 #[derive(Debug)]
-pub(crate) struct SimpleMessage {
-    kind: ErrorKind,
-    message: &'static str,
-}
-
-impl SimpleMessage {
-    pub(crate) const fn new(kind: ErrorKind, message: &'static str) -> Self {
-        Self { kind, message }
-    }
+pub struct SimpleMessage {
+    pub kind: ErrorKind,
+    pub message: &'static str,
 }
 
-/// Creates and returns an `io::Error` for a given `ErrorKind` and constant
-/// message. This doesn't allocate.
-pub(crate) macro const_io_error($kind:expr, $message:expr $(,)?) {
-    $crate::io::error::Error::from_static_message({
-        const MESSAGE_DATA: $crate::io::error::SimpleMessage =
-            $crate::io::error::SimpleMessage::new($kind, $message);
-        &MESSAGE_DATA
-    })
+/// Creates a new I/O error from a known kind of error and a string literal.
+///
+/// Contrary to [`Error::new`], this macro does not allocate and can be used in
+/// `const` contexts.
+///
+/// # Example
+/// ```
+/// #![feature(io_const_error)]
+/// use std::io::{const_error, Error, ErrorKind};
+///
+/// const FAIL: Error = const_error!(ErrorKind::Unsupported, "tried something that never works");
+///
+/// fn not_here() -> Result<(), Error> {
+///     Err(FAIL)
+/// }
+/// ```
+#[rustc_macro_transparency = "semitransparent"]
+#[unstable(feature = "io_const_error", issue = "133448")]
+#[allow_internal_unstable(hint_must_use, io_const_error_internals)]
+pub macro const_error($kind:expr, $message:expr $(,)?) {
+    $crate::hint::must_use($crate::io::Error::from_static_message(
+        const { &$crate::io::SimpleMessage { kind: $kind, message: $message } },
+    ))
 }
 
 // As with `SimpleMessage`: `#[repr(align(4))]` here is just because
@@ -592,13 +603,15 @@ impl Error {
     ///
     /// This function does not allocate.
     ///
-    /// You should not use this directly, and instead use the `const_io_error!`
-    /// macro: `io::const_io_error!(ErrorKind::Something, "some_message")`.
+    /// You should not use this directly, and instead use the `const_error!`
+    /// macro: `io::const_error!(ErrorKind::Something, "some_message")`.
     ///
     /// This function should maybe change to `from_static_message<const MSG: &'static
     /// str>(kind: ErrorKind)` in the future, when const generics allow that.
     #[inline]
-    pub(crate) const fn from_static_message(msg: &'static SimpleMessage) -> Error {
+    #[doc(hidden)]
+    #[unstable(feature = "io_const_error_internals", issue = "none")]
+    pub const fn from_static_message(msg: &'static SimpleMessage) -> Error {
         Self { repr: Repr::new_simple_message(msg) }
     }
 
diff --git a/library/std/src/io/error/tests.rs b/library/std/src/io/error/tests.rs
index 00d04984a38..edac6563478 100644
--- a/library/std/src/io/error/tests.rs
+++ b/library/std/src/io/error/tests.rs
@@ -1,4 +1,4 @@
-use super::{Custom, Error, ErrorData, ErrorKind, Repr, SimpleMessage, const_io_error};
+use super::{Custom, Error, ErrorData, ErrorKind, Repr, SimpleMessage, const_error};
 use crate::assert_matches::assert_matches;
 use crate::mem::size_of;
 use crate::sys::decode_error_kind;
@@ -60,7 +60,7 @@ fn test_downcasting() {
 
 #[test]
 fn test_const() {
-    const E: Error = const_io_error!(ErrorKind::NotFound, "hello");
+    const E: Error = const_error!(ErrorKind::NotFound, "hello");
 
     assert_eq!(E.kind(), ErrorKind::NotFound);
     assert_eq!(E.to_string(), "hello");
@@ -110,13 +110,13 @@ fn test_simple_message_packing() {
         }};
     }
 
-    let not_static = const_io_error!(Uncategorized, "not a constant!");
+    let not_static = const_error!(Uncategorized, "not a constant!");
     check_simple_msg!(not_static, Uncategorized, "not a constant!");
 
-    const CONST: Error = const_io_error!(NotFound, "definitely a constant!");
+    const CONST: Error = const_error!(NotFound, "definitely a constant!");
     check_simple_msg!(CONST, NotFound, "definitely a constant!");
 
-    static STATIC: Error = const_io_error!(BrokenPipe, "a constant, sort of!");
+    static STATIC: Error = const_error!(BrokenPipe, "a constant, sort of!");
     check_simple_msg!(STATIC, BrokenPipe, "a constant, sort of!");
 }
 
diff --git a/library/std/src/io/mod.rs b/library/std/src/io/mod.rs
index 21e70774954..4ffb0463006 100644
--- a/library/std/src/io/mod.rs
+++ b/library/std/src/io/mod.rs
@@ -301,12 +301,15 @@ mod tests;
 pub use core::io::{BorrowedBuf, BorrowedCursor};
 use core::slice::memchr;
 
-pub(crate) use error::const_io_error;
-
 #[stable(feature = "bufwriter_into_parts", since = "1.56.0")]
 pub use self::buffered::WriterPanicked;
 #[unstable(feature = "raw_os_error_ty", issue = "107792")]
 pub use self::error::RawOsError;
+#[doc(hidden)]
+#[unstable(feature = "io_const_error_internals", issue = "none")]
+pub use self::error::SimpleMessage;
+#[unstable(feature = "io_const_error", issue = "133448")]
+pub use self::error::const_error;
 #[stable(feature = "is_terminal", since = "1.70.0")]
 pub use self::stdio::IsTerminal;
 pub(crate) use self::stdio::attempt_print_to_stderr;
diff --git a/library/std/src/io/tests.rs b/library/std/src/io/tests.rs
index 89e806c0891..47cbb9614af 100644
--- a/library/std/src/io/tests.rs
+++ b/library/std/src/io/tests.rs
@@ -225,12 +225,12 @@ fn take_eof() {
 
     impl Read for R {
         fn read(&mut self, _: &mut [u8]) -> io::Result<usize> {
-            Err(io::const_io_error!(io::ErrorKind::Other, ""))
+            Err(io::const_error!(io::ErrorKind::Other, ""))
         }
     }
     impl BufRead for R {
         fn fill_buf(&mut self) -> io::Result<&[u8]> {
-            Err(io::const_io_error!(io::ErrorKind::Other, ""))
+            Err(io::const_error!(io::ErrorKind::Other, ""))
         }
         fn consume(&mut self, _amt: usize) {}
     }
diff --git a/library/std/src/lib.rs b/library/std/src/lib.rs
index ee6fceb024f..cf99a618e55 100644
--- a/library/std/src/lib.rs
+++ b/library/std/src/lib.rs
@@ -340,6 +340,7 @@
 #![feature(fmt_internals)]
 #![feature(hasher_prefixfree_extras)]
 #![feature(hashmap_internals)]
+#![feature(hint_must_use)]
 #![feature(ip)]
 #![feature(lazy_get)]
 #![feature(maybe_uninit_slice)]
@@ -410,6 +411,7 @@
 // Only for const-ness:
 // tidy-alphabetical-start
 #![feature(const_collections_with_hasher)]
+#![feature(io_const_error)]
 #![feature(thread_local_internals)]
 // tidy-alphabetical-end
 //
diff --git a/library/std/src/net/mod.rs b/library/std/src/net/mod.rs
index 3b19c743b1e..ddd3b68dd2d 100644
--- a/library/std/src/net/mod.rs
+++ b/library/std/src/net/mod.rs
@@ -84,6 +84,6 @@ where
         }
     }
     Err(last_err.unwrap_or_else(|| {
-        io::const_io_error!(ErrorKind::InvalidInput, "could not resolve to any addresses")
+        io::const_error!(ErrorKind::InvalidInput, "could not resolve to any addresses")
     }))
 }
diff --git a/library/std/src/net/udp.rs b/library/std/src/net/udp.rs
index 6df47d7b0e0..674c5fb7d6e 100644
--- a/library/std/src/net/udp.rs
+++ b/library/std/src/net/udp.rs
@@ -203,9 +203,7 @@ impl UdpSocket {
     pub fn send_to<A: ToSocketAddrs>(&self, buf: &[u8], addr: A) -> io::Result<usize> {
         match addr.to_socket_addrs()?.next() {
             Some(addr) => self.0.send_to(buf, &addr),
-            None => {
-                Err(io::const_io_error!(ErrorKind::InvalidInput, "no addresses to send data to"))
-            }
+            None => Err(io::const_error!(ErrorKind::InvalidInput, "no addresses to send data to")),
         }
     }
 
diff --git a/library/std/src/os/unix/net/addr.rs b/library/std/src/os/unix/net/addr.rs
index 253e1503cf7..56789f235fd 100644
--- a/library/std/src/os/unix/net/addr.rs
+++ b/library/std/src/os/unix/net/addr.rs
@@ -30,14 +30,14 @@ pub(super) fn sockaddr_un(path: &Path) -> io::Result<(libc::sockaddr_un, libc::s
     let bytes = path.as_os_str().as_bytes();
 
     if bytes.contains(&0) {
-        return Err(io::const_io_error!(
+        return Err(io::const_error!(
             io::ErrorKind::InvalidInput,
             "paths must not contain interior null bytes",
         ));
     }
 
     if bytes.len() >= addr.sun_path.len() {
-        return Err(io::const_io_error!(
+        return Err(io::const_error!(
             io::ErrorKind::InvalidInput,
             "path must be shorter than SUN_LEN",
         ));
@@ -119,7 +119,7 @@ impl SocketAddr {
             // linux returns zero bytes of address
             len = SUN_PATH_OFFSET as libc::socklen_t; // i.e., zero-length address
         } else if addr.sun_family != libc::AF_UNIX as libc::sa_family_t {
-            return Err(io::const_io_error!(
+            return Err(io::const_error!(
                 io::ErrorKind::InvalidInput,
                 "file descriptor did not correspond to a Unix socket",
             ));
@@ -273,7 +273,7 @@ impl linux_ext::addr::SocketAddrExt for SocketAddr {
             addr.sun_family = libc::AF_UNIX as libc::sa_family_t;
 
             if name.len() + 1 > addr.sun_path.len() {
-                return Err(io::const_io_error!(
+                return Err(io::const_error!(
                     io::ErrorKind::InvalidInput,
                     "abstract socket name must be shorter than SUN_LEN",
                 ));
diff --git a/library/std/src/os/wasi/fs.rs b/library/std/src/os/wasi/fs.rs
index 9ec3e387e2b..42aada131da 100644
--- a/library/std/src/os/wasi/fs.rs
+++ b/library/std/src/os/wasi/fs.rs
@@ -261,7 +261,7 @@ impl FileExt for fs::File {
             a if a == wasi::ADVICE_DONTNEED.raw() => wasi::ADVICE_DONTNEED,
             a if a == wasi::ADVICE_NOREUSE.raw() => wasi::ADVICE_NOREUSE,
             _ => {
-                return Err(io::const_io_error!(
+                return Err(io::const_error!(
                     io::ErrorKind::InvalidInput,
                     "invalid parameter 'advice'",
                 ));
@@ -560,6 +560,5 @@ pub fn symlink_path<P: AsRef<Path>, U: AsRef<Path>>(old_path: P, new_path: U) ->
 }
 
 fn osstr2str(f: &OsStr) -> io::Result<&str> {
-    f.to_str()
-        .ok_or_else(|| io::const_io_error!(io::ErrorKind::Uncategorized, "input must be utf-8"))
+    f.to_str().ok_or_else(|| io::const_error!(io::ErrorKind::Uncategorized, "input must be utf-8"))
 }
diff --git a/library/std/src/os/windows/io/socket.rs b/library/std/src/os/windows/io/socket.rs
index 1fcfb6e73ad..272641ea6c7 100644
--- a/library/std/src/os/windows/io/socket.rs
+++ b/library/std/src/os/windows/io/socket.rs
@@ -101,7 +101,7 @@ impl OwnedSocket {
 
     #[cfg(target_vendor = "uwp")]
     pub(crate) fn set_no_inherit(&self) -> io::Result<()> {
-        Err(io::const_io_error!(io::ErrorKind::Unsupported, "Unavailable on UWP"))
+        Err(io::const_error!(io::ErrorKind::Unsupported, "Unavailable on UWP"))
     }
 }
 
diff --git a/library/std/src/path.rs b/library/std/src/path.rs
index 7ffb11b6aed..33a3e4332f3 100644
--- a/library/std/src/path.rs
+++ b/library/std/src/path.rs
@@ -3581,7 +3581,7 @@ impl Error for StripPrefixError {
 pub fn absolute<P: AsRef<Path>>(path: P) -> io::Result<PathBuf> {
     let path = path.as_ref();
     if path.as_os_str().is_empty() {
-        Err(io::const_io_error!(io::ErrorKind::InvalidInput, "cannot make an empty path absolute",))
+        Err(io::const_error!(io::ErrorKind::InvalidInput, "cannot make an empty path absolute",))
     } else {
         sys::path::absolute(path)
     }
diff --git a/library/std/src/sys/pal/common/small_c_string.rs b/library/std/src/sys/pal/common/small_c_string.rs
index 3c96714b5c5..f54505a856e 100644
--- a/library/std/src/sys/pal/common/small_c_string.rs
+++ b/library/std/src/sys/pal/common/small_c_string.rs
@@ -11,7 +11,7 @@ const MAX_STACK_ALLOCATION: usize = 384;
 const MAX_STACK_ALLOCATION: usize = 32;
 
 const NUL_ERR: io::Error =
-    io::const_io_error!(io::ErrorKind::InvalidInput, "file name contained an unexpected NUL byte");
+    io::const_error!(io::ErrorKind::InvalidInput, "file name contained an unexpected NUL byte");
 
 #[inline]
 pub fn run_path_with_cstr<T>(path: &Path, f: &dyn Fn(&CStr) -> io::Result<T>) -> io::Result<T> {
diff --git a/library/std/src/sys/pal/hermit/fs.rs b/library/std/src/sys/pal/hermit/fs.rs
index 17d15ed2e50..11862a07608 100644
--- a/library/std/src/sys/pal/hermit/fs.rs
+++ b/library/std/src/sys/pal/hermit/fs.rs
@@ -294,7 +294,7 @@ impl OpenOptions {
             (false, _, true) => Ok(O_WRONLY | O_APPEND),
             (true, _, true) => Ok(O_RDWR | O_APPEND),
             (false, false, false) => {
-                Err(io::const_io_error!(ErrorKind::InvalidInput, "invalid access mode"))
+                Err(io::const_error!(ErrorKind::InvalidInput, "invalid access mode"))
             }
         }
     }
@@ -304,18 +304,16 @@ impl OpenOptions {
             (true, false) => {}
             (false, false) => {
                 if self.truncate || self.create || self.create_new {
-                    return Err(io::const_io_error!(
-                        ErrorKind::InvalidInput,
-                        "invalid creation mode",
-                    ));
+                    return Err(
+                        io::const_error!(ErrorKind::InvalidInput, "invalid creation mode",),
+                    );
                 }
             }
             (_, true) => {
                 if self.truncate && !self.create_new {
-                    return Err(io::const_io_error!(
-                        ErrorKind::InvalidInput,
-                        "invalid creation mode",
-                    ));
+                    return Err(
+                        io::const_error!(ErrorKind::InvalidInput, "invalid creation mode",),
+                    );
                 }
             }
         }
diff --git a/library/std/src/sys/pal/hermit/mod.rs b/library/std/src/sys/pal/hermit/mod.rs
index b62afb40a61..f03fca60344 100644
--- a/library/std/src/sys/pal/hermit/mod.rs
+++ b/library/std/src/sys/pal/hermit/mod.rs
@@ -42,7 +42,7 @@ pub fn unsupported<T>() -> crate::io::Result<T> {
 }
 
 pub fn unsupported_err() -> crate::io::Error {
-    crate::io::const_io_error!(
+    crate::io::const_error!(
         crate::io::ErrorKind::Unsupported,
         "operation not supported on HermitCore yet",
     )
diff --git a/library/std/src/sys/pal/hermit/net.rs b/library/std/src/sys/pal/hermit/net.rs
index d9baa091a23..4e12374203e 100644
--- a/library/std/src/sys/pal/hermit/net.rs
+++ b/library/std/src/sys/pal/hermit/net.rs
@@ -87,7 +87,7 @@ impl Socket {
         loop {
             let elapsed = start.elapsed();
             if elapsed >= timeout {
-                return Err(io::const_io_error!(io::ErrorKind::TimedOut, "connection timed out"));
+                return Err(io::const_error!(io::ErrorKind::TimedOut, "connection timed out"));
             }
 
             let timeout = timeout - elapsed;
@@ -114,7 +114,7 @@ impl Socket {
                     // 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::const_error!(
                                 io::ErrorKind::Uncategorized,
                                 "no error set after POLLHUP",
                             )
diff --git a/library/std/src/sys/pal/hermit/thread.rs b/library/std/src/sys/pal/hermit/thread.rs
index 41f2c3e2123..2a0b8dcb4ed 100644
--- a/library/std/src/sys/pal/hermit/thread.rs
+++ b/library/std/src/sys/pal/hermit/thread.rs
@@ -41,7 +41,7 @@ impl Thread {
             unsafe {
                 drop(Box::from_raw(p));
             }
-            Err(io::const_io_error!(io::ErrorKind::Uncategorized, "Unable to create thread!"))
+            Err(io::const_error!(io::ErrorKind::Uncategorized, "Unable to create thread!"))
         } else {
             Ok(Thread { tid: tid })
         };
diff --git a/library/std/src/sys/pal/sgx/mod.rs b/library/std/src/sys/pal/sgx/mod.rs
index 586ccd18c2f..ce8a2fed4bc 100644
--- a/library/std/src/sys/pal/sgx/mod.rs
+++ b/library/std/src/sys/pal/sgx/mod.rs
@@ -48,7 +48,7 @@ pub fn unsupported<T>() -> crate::io::Result<T> {
 }
 
 pub fn unsupported_err() -> crate::io::Error {
-    crate::io::const_io_error!(ErrorKind::Unsupported, "operation not supported on SGX yet")
+    crate::io::const_error!(ErrorKind::Unsupported, "operation not supported on SGX yet")
 }
 
 /// This function is used to implement various functions that doesn't exist,
@@ -59,7 +59,7 @@ pub fn unsupported_err() -> crate::io::Error {
 pub fn sgx_ineffective<T>(v: T) -> crate::io::Result<T> {
     static SGX_INEFFECTIVE_ERROR: AtomicBool = AtomicBool::new(false);
     if SGX_INEFFECTIVE_ERROR.load(Ordering::Relaxed) {
-        Err(crate::io::const_io_error!(
+        Err(crate::io::const_error!(
             ErrorKind::Uncategorized,
             "operation can't be trusted to have any effect on SGX",
         ))
diff --git a/library/std/src/sys/pal/solid/fs.rs b/library/std/src/sys/pal/solid/fs.rs
index 776a96ff3b7..04dd10ad806 100644
--- a/library/std/src/sys/pal/solid/fs.rs
+++ b/library/std/src/sys/pal/solid/fs.rs
@@ -303,7 +303,7 @@ fn cstr(path: &Path) -> io::Result<CString> {
 
     if !path.starts_with(br"\") {
         // Relative paths aren't supported
-        return Err(crate::io::const_io_error!(
+        return Err(crate::io::const_error!(
             crate::io::ErrorKind::Unsupported,
             "relative path is not supported on this platform",
         ));
@@ -314,10 +314,7 @@ fn cstr(path: &Path) -> io::Result<CString> {
     let wrapped_path = [SAFE_PREFIX, &path, &[0]].concat();
 
     CString::from_vec_with_nul(wrapped_path).map_err(|_| {
-        crate::io::const_io_error!(
-            io::ErrorKind::InvalidInput,
-            "path provided contains a nul byte",
-        )
+        crate::io::const_error!(io::ErrorKind::InvalidInput, "path provided contains a nul byte",)
     })
 }
 
@@ -512,7 +509,7 @@ impl fmt::Debug for File {
 
 pub fn unlink(p: &Path) -> io::Result<()> {
     if stat(p)?.file_type().is_dir() {
-        Err(io::const_io_error!(io::ErrorKind::IsADirectory, "is a directory"))
+        Err(io::const_error!(io::ErrorKind::IsADirectory, "is a directory"))
     } else {
         error::SolidError::err_if_negative(unsafe { abi::SOLID_FS_Unlink(cstr(p)?.as_ptr()) })
             .map_err(|e| e.as_io_error())?;
@@ -542,7 +539,7 @@ pub fn rmdir(p: &Path) -> io::Result<()> {
             .map_err(|e| e.as_io_error())?;
         Ok(())
     } else {
-        Err(io::const_io_error!(io::ErrorKind::NotADirectory, "not a directory"))
+        Err(io::const_error!(io::ErrorKind::NotADirectory, "not a directory"))
     }
 }
 
@@ -570,7 +567,7 @@ pub fn remove_dir_all(path: &Path) -> io::Result<()> {
 pub fn readlink(p: &Path) -> io::Result<PathBuf> {
     // This target doesn't support symlinks
     stat(p)?;
-    Err(io::const_io_error!(io::ErrorKind::InvalidInput, "not a symbolic link"))
+    Err(io::const_error!(io::ErrorKind::InvalidInput, "not a symbolic link"))
 }
 
 pub fn symlink(_original: &Path, _link: &Path) -> io::Result<()> {
diff --git a/library/std/src/sys/pal/solid/net.rs b/library/std/src/sys/pal/solid/net.rs
index c0818ecd856..5f6436807e2 100644
--- a/library/std/src/sys/pal/solid/net.rs
+++ b/library/std/src/sys/pal/solid/net.rs
@@ -175,7 +175,7 @@ impl Socket {
         };
 
         match n {
-            0 => Err(io::const_io_error!(io::ErrorKind::TimedOut, "connection timed out")),
+            0 => Err(io::const_error!(io::ErrorKind::TimedOut, "connection timed out")),
             _ => {
                 let can_write = writefds.num_fds != 0;
                 if !can_write {
diff --git a/library/std/src/sys/pal/solid/os.rs b/library/std/src/sys/pal/solid/os.rs
index d8afcb91f67..57c28aed3b2 100644
--- a/library/std/src/sys/pal/solid/os.rs
+++ b/library/std/src/sys/pal/solid/os.rs
@@ -204,7 +204,7 @@ pub unsafe fn unsetenv(n: &OsStr) -> io::Result<()> {
 /// In kmclib, `setenv` and `unsetenv` don't always set `errno`, so this
 /// function just returns a generic error.
 fn cvt_env(t: c_int) -> io::Result<c_int> {
-    if t == -1 { Err(io::const_io_error!(io::ErrorKind::Uncategorized, "failure")) } else { Ok(t) }
+    if t == -1 { Err(io::const_error!(io::ErrorKind::Uncategorized, "failure")) } else { Ok(t) }
 }
 
 pub fn temp_dir() -> PathBuf {
diff --git a/library/std/src/sys/pal/uefi/helpers.rs b/library/std/src/sys/pal/uefi/helpers.rs
index abc8e69a285..47d9add72b5 100644
--- a/library/std/src/sys/pal/uefi/helpers.rs
+++ b/library/std/src/sys/pal/uefi/helpers.rs
@@ -13,7 +13,7 @@ use r_efi::efi::{self, Guid};
 use r_efi::protocols::{device_path, device_path_to_text, shell};
 
 use crate::ffi::{OsStr, OsString};
-use crate::io::{self, const_io_error};
+use crate::io::{self, const_error};
 use crate::mem::{MaybeUninit, size_of};
 use crate::os::uefi::env::boot_services;
 use crate::os::uefi::ffi::{OsStrExt, OsStringExt};
@@ -30,7 +30,7 @@ type BootUninstallMultipleProtocolInterfaces =
     unsafe extern "efiapi" fn(_: r_efi::efi::Handle, _: ...) -> r_efi::efi::Status;
 
 const BOOT_SERVICES_UNAVAILABLE: io::Error =
-    const_io_error!(io::ErrorKind::Other, "Boot Services are no longer available");
+    const_error!(io::ErrorKind::Other, "Boot Services are no longer available");
 
 /// Locates Handles with a particular Protocol GUID.
 ///
@@ -114,7 +114,7 @@ pub(crate) fn open_protocol<T>(
         Err(crate::io::Error::from_raw_os_error(r.as_usize()))
     } else {
         NonNull::new(unsafe { protocol.assume_init() })
-            .ok_or(const_io_error!(io::ErrorKind::Other, "null protocol"))
+            .ok_or(const_error!(io::ErrorKind::Other, "null protocol"))
     }
 }
 
@@ -134,7 +134,7 @@ pub(crate) fn create_event(
     if r.is_error() {
         Err(crate::io::Error::from_raw_os_error(r.as_usize()))
     } else {
-        NonNull::new(event).ok_or(const_io_error!(io::ErrorKind::Other, "null protocol"))
+        NonNull::new(event).ok_or(const_error!(io::ErrorKind::Other, "null protocol"))
     }
 }
 
@@ -155,10 +155,8 @@ pub(crate) unsafe fn close_event(evt: NonNull<crate::ffi::c_void>) -> io::Result
 ///
 /// Note: Some protocols need to be manually freed. It is the caller's responsibility to do so.
 pub(crate) fn image_handle_protocol<T>(protocol_guid: Guid) -> io::Result<NonNull<T>> {
-    let system_handle = uefi::env::try_image_handle().ok_or(io::const_io_error!(
-        io::ErrorKind::NotFound,
-        "Protocol not found in Image handle"
-    ))?;
+    let system_handle = uefi::env::try_image_handle()
+        .ok_or(io::const_error!(io::ErrorKind::NotFound, "Protocol not found in Image handle"))?;
     open_protocol(system_handle, protocol_guid)
 }
 
@@ -178,7 +176,7 @@ pub(crate) fn device_path_to_text(path: NonNull<device_path::Protocol>) -> io::R
         };
 
         let path = os_string_from_raw(path_ptr)
-            .ok_or(io::const_io_error!(io::ErrorKind::InvalidData, "Invalid path"))?;
+            .ok_or(io::const_error!(io::ErrorKind::InvalidData, "Invalid path"))?;
 
         if let Some(boot_services) = crate::os::uefi::env::boot_services() {
             let boot_services: NonNull<r_efi::efi::BootServices> = boot_services.cast();
@@ -213,7 +211,7 @@ pub(crate) fn device_path_to_text(path: NonNull<device_path::Protocol>) -> io::R
         }
     }
 
-    Err(io::const_io_error!(io::ErrorKind::NotFound, "No device path to text protocol found"))
+    Err(io::const_error!(io::ErrorKind::NotFound, "No device path to text protocol found"))
 }
 
 /// Gets RuntimeServices.
@@ -234,7 +232,7 @@ impl DevicePath {
         ) -> io::Result<DevicePath> {
             let path_vec = p.encode_wide().chain(Some(0)).collect::<Vec<u16>>();
             if path_vec[..path_vec.len() - 1].contains(&0) {
-                return Err(const_io_error!(
+                return Err(const_error!(
                     io::ErrorKind::InvalidInput,
                     "strings passed to UEFI cannot contain NULs",
                 ));
@@ -243,9 +241,9 @@ impl DevicePath {
             let path =
                 unsafe { ((*protocol.as_ptr()).convert_text_to_device_path)(path_vec.as_ptr()) };
 
-            NonNull::new(path).map(DevicePath).ok_or_else(|| {
-                const_io_error!(io::ErrorKind::InvalidFilename, "Invalid Device Path")
-            })
+            NonNull::new(path)
+                .map(DevicePath)
+                .ok_or_else(|| const_error!(io::ErrorKind::InvalidFilename, "Invalid Device Path"))
         }
 
         static LAST_VALID_HANDLE: AtomicPtr<crate::ffi::c_void> =
@@ -271,7 +269,7 @@ impl DevicePath {
             }
         }
 
-        io::Result::Err(const_io_error!(
+        io::Result::Err(const_error!(
             io::ErrorKind::NotFound,
             "DevicePathFromText Protocol not found"
         ))
@@ -326,7 +324,7 @@ impl<T> OwnedProtocol<T> {
         };
 
         let handle = NonNull::new(handle)
-            .ok_or(io::const_io_error!(io::ErrorKind::Uncategorized, "found null handle"))?;
+            .ok_or(io::const_error!(io::ErrorKind::Uncategorized, "found null handle"))?;
 
         Ok(Self { guid, handle, protocol })
     }
diff --git a/library/std/src/sys/pal/uefi/mod.rs b/library/std/src/sys/pal/uefi/mod.rs
index c0ab52f650a..f29c91f3bfe 100644
--- a/library/std/src/sys/pal/uefi/mod.rs
+++ b/library/std/src/sys/pal/uefi/mod.rs
@@ -95,7 +95,7 @@ pub const fn unsupported<T>() -> std_io::Result<T> {
 
 #[inline]
 pub const fn unsupported_err() -> std_io::Error {
-    std_io::const_io_error!(std_io::ErrorKind::Unsupported, "operation not supported on UEFI",)
+    std_io::const_error!(std_io::ErrorKind::Unsupported, "operation not supported on UEFI",)
 }
 
 pub fn decode_error_kind(code: RawOsError) -> crate::io::ErrorKind {
diff --git a/library/std/src/sys/pal/uefi/os.rs b/library/std/src/sys/pal/uefi/os.rs
index 27395f7c3c0..6d23c72ef22 100644
--- a/library/std/src/sys/pal/uefi/os.rs
+++ b/library/std/src/sys/pal/uefi/os.rs
@@ -131,7 +131,7 @@ pub fn getcwd() -> io::Result<PathBuf> {
             let path_ptr = unsafe { ((*shell.as_ptr()).get_cur_dir)(crate::ptr::null_mut()) };
             helpers::os_string_from_raw(path_ptr)
                 .map(PathBuf::from)
-                .ok_or(io::const_io_error!(io::ErrorKind::InvalidData, "Invalid path"))
+                .ok_or(io::const_error!(io::ErrorKind::InvalidData, "Invalid path"))
         }
         None => {
             let mut t = current_exe()?;
@@ -147,7 +147,7 @@ pub fn chdir(p: &path::Path) -> io::Result<()> {
     let shell = helpers::open_shell().ok_or(unsupported_err())?;
 
     let mut p = helpers::os_string_to_raw(p.as_os_str())
-        .ok_or(io::const_io_error!(io::ErrorKind::InvalidData, "Invalid path"))?;
+        .ok_or(io::const_error!(io::ErrorKind::InvalidData, "Invalid path"))?;
 
     let r = unsafe { ((*shell.as_ptr()).set_cur_dir)(crate::ptr::null_mut(), p.as_mut_ptr()) };
     if r.is_error() { Err(io::Error::from_raw_os_error(r.as_usize())) } else { Ok(()) }
@@ -290,15 +290,15 @@ mod uefi_env {
 
     pub(crate) fn set(key: &OsStr, val: &OsStr) -> io::Result<()> {
         let mut key_ptr = helpers::os_string_to_raw(key)
-            .ok_or(io::const_io_error!(io::ErrorKind::InvalidInput, "Invalid Key"))?;
+            .ok_or(io::const_error!(io::ErrorKind::InvalidInput, "Invalid Key"))?;
         let mut val_ptr = helpers::os_string_to_raw(val)
-            .ok_or(io::const_io_error!(io::ErrorKind::InvalidInput, "Invalid Value"))?;
+            .ok_or(io::const_error!(io::ErrorKind::InvalidInput, "Invalid Value"))?;
         unsafe { set_raw(key_ptr.as_mut_ptr(), val_ptr.as_mut_ptr()) }
     }
 
     pub(crate) fn unset(key: &OsStr) -> io::Result<()> {
         let mut key_ptr = helpers::os_string_to_raw(key)
-            .ok_or(io::const_io_error!(io::ErrorKind::InvalidInput, "Invalid Key"))?;
+            .ok_or(io::const_error!(io::ErrorKind::InvalidInput, "Invalid Key"))?;
         unsafe { set_raw(key_ptr.as_mut_ptr(), crate::ptr::null_mut()) }
     }
 
@@ -328,7 +328,7 @@ mod uefi_env {
                 });
                 // SAFETY: val.add(start) is always NULL terminated
                 let val = unsafe { get_raw(shell, val.add(start)) }
-                    .ok_or(io::const_io_error!(io::ErrorKind::InvalidInput, "Invalid Value"))?;
+                    .ok_or(io::const_error!(io::ErrorKind::InvalidInput, "Invalid Value"))?;
 
                 vars.push((key, val));
                 start = i + 1;
diff --git a/library/std/src/sys/pal/uefi/process.rs b/library/std/src/sys/pal/uefi/process.rs
index 1b83f4b0aee..95707ebb7f0 100644
--- a/library/std/src/sys/pal/uefi/process.rs
+++ b/library/std/src/sys/pal/uefi/process.rs
@@ -307,7 +307,7 @@ mod uefi_command_internal {
 
     use super::super::helpers;
     use crate::ffi::{OsStr, OsString};
-    use crate::io::{self, const_io_error};
+    use crate::io::{self, const_error};
     use crate::mem::MaybeUninit;
     use crate::os::uefi::env::{boot_services, image_handle, system_table};
     use crate::os::uefi::ffi::{OsStrExt, OsStringExt};
@@ -328,7 +328,7 @@ mod uefi_command_internal {
         pub fn load_image(p: &OsStr) -> io::Result<Self> {
             let path = helpers::DevicePath::from_text(p)?;
             let boot_services: NonNull<r_efi::efi::BootServices> = boot_services()
-                .ok_or_else(|| const_io_error!(io::ErrorKind::NotFound, "Boot Services not found"))?
+                .ok_or_else(|| const_error!(io::ErrorKind::NotFound, "Boot Services not found"))?
                 .cast();
             let mut child_handle: MaybeUninit<r_efi::efi::Handle> = MaybeUninit::uninit();
             let image_handle = image_handle();
@@ -369,7 +369,7 @@ mod uefi_command_internal {
             }
 
             let boot_services: NonNull<r_efi::efi::BootServices> = boot_services()
-                .ok_or_else(|| const_io_error!(io::ErrorKind::NotFound, "Boot Services not found"))?
+                .ok_or_else(|| const_error!(io::ErrorKind::NotFound, "Boot Services not found"))?
                 .cast();
             let mut exit_data_size: usize = 0;
             let mut exit_data: MaybeUninit<*mut u16> = MaybeUninit::uninit();
@@ -583,7 +583,7 @@ mod uefi_command_internal {
             OsString::from_wide(&self._buffer)
                 .into_string()
                 .map(Into::into)
-                .map_err(|_| const_io_error!(io::ErrorKind::Other, "utf8 conversion failed"))
+                .map_err(|_| const_error!(io::ErrorKind::Other, "utf8 conversion failed"))
         }
 
         extern "efiapi" fn reset(
diff --git a/library/std/src/sys/pal/unix/fs.rs b/library/std/src/sys/pal/unix/fs.rs
index 96f99efb21e..37029bcd36e 100644
--- a/library/std/src/sys/pal/unix/fs.rs
+++ b/library/std/src/sys/pal/unix/fs.rs
@@ -559,7 +559,7 @@ impl FileAttr {
                 return if (ext.stx_mask & libc::STATX_BTIME) != 0 {
                     SystemTime::new(ext.stx_btime.tv_sec, ext.stx_btime.tv_nsec as i64)
                 } else {
-                    Err(io::const_io_error!(
+                    Err(io::const_error!(
                         io::ErrorKind::Unsupported,
                         "creation time is not available for the filesystem",
                     ))
@@ -567,7 +567,7 @@ impl FileAttr {
             }
         }
 
-        Err(io::const_io_error!(
+        Err(io::const_error!(
             io::ErrorKind::Unsupported,
             "creation time is not available on this platform \
                             currently",
@@ -1272,7 +1272,7 @@ impl File {
         target_vendor = "apple",
     )))]
     pub fn lock(&self) -> io::Result<()> {
-        Err(io::const_io_error!(io::ErrorKind::Unsupported, "lock() not supported"))
+        Err(io::const_error!(io::ErrorKind::Unsupported, "lock() not supported"))
     }
 
     #[cfg(any(
@@ -1293,7 +1293,7 @@ impl File {
         target_vendor = "apple",
     )))]
     pub fn lock_shared(&self) -> io::Result<()> {
-        Err(io::const_io_error!(io::ErrorKind::Unsupported, "lock_shared() not supported"))
+        Err(io::const_error!(io::ErrorKind::Unsupported, "lock_shared() not supported"))
     }
 
     #[cfg(any(
@@ -1320,7 +1320,7 @@ impl File {
         target_vendor = "apple",
     )))]
     pub fn try_lock(&self) -> io::Result<bool> {
-        Err(io::const_io_error!(io::ErrorKind::Unsupported, "try_lock() not supported"))
+        Err(io::const_error!(io::ErrorKind::Unsupported, "try_lock() not supported"))
     }
 
     #[cfg(any(
@@ -1347,7 +1347,7 @@ impl File {
         target_vendor = "apple",
     )))]
     pub fn try_lock_shared(&self) -> io::Result<bool> {
-        Err(io::const_io_error!(io::ErrorKind::Unsupported, "try_lock_shared() not supported"))
+        Err(io::const_error!(io::ErrorKind::Unsupported, "try_lock_shared() not supported"))
     }
 
     #[cfg(any(
@@ -1368,7 +1368,7 @@ impl File {
         target_vendor = "apple",
     )))]
     pub fn unlock(&self) -> io::Result<()> {
-        Err(io::const_io_error!(io::ErrorKind::Unsupported, "unlock() not supported"))
+        Err(io::const_error!(io::ErrorKind::Unsupported, "unlock() not supported"))
     }
 
     pub fn truncate(&self, size: u64) -> io::Result<()> {
@@ -1459,11 +1459,11 @@ impl File {
         )))]
         let to_timespec = |time: Option<SystemTime>| match time {
             Some(time) if let Some(ts) = time.t.to_timespec() => Ok(ts),
-            Some(time) if time > crate::sys::time::UNIX_EPOCH => Err(io::const_io_error!(
+            Some(time) if time > crate::sys::time::UNIX_EPOCH => Err(io::const_error!(
                 io::ErrorKind::InvalidInput,
                 "timestamp is too large to set as a file time"
             )),
-            Some(_) => Err(io::const_io_error!(
+            Some(_) => Err(io::const_error!(
                 io::ErrorKind::InvalidInput,
                 "timestamp is too small to set as a file time"
             )),
@@ -1476,7 +1476,7 @@ impl File {
                 // the same as for Redox.
                 // `futimens` and `UTIME_OMIT` are a work in progress for vxworks.
                 let _ = times;
-                Err(io::const_io_error!(
+                Err(io::const_error!(
                     io::ErrorKind::Unsupported,
                     "setting file times not supported",
                 ))
@@ -1515,7 +1515,7 @@ impl File {
                     weak!(fn futimens(c_int, *const libc::timespec) -> c_int);
                     match futimens.get() {
                         Some(futimens) => futimens(self.as_raw_fd(), times.as_ptr()),
-                        None => return Err(io::const_io_error!(
+                        None => return Err(io::const_error!(
                             io::ErrorKind::Unsupported,
                             "setting file times requires Android API level >= 19",
                         )),
@@ -2090,7 +2090,7 @@ pub fn lchown(path: &Path, uid: u32, gid: u32) -> io::Result<()> {
 #[cfg(target_os = "vxworks")]
 pub fn lchown(path: &Path, uid: u32, gid: u32) -> io::Result<()> {
     let (_, _, _) = (path, uid, gid);
-    Err(io::const_io_error!(io::ErrorKind::Unsupported, "lchown not supported by vxworks"))
+    Err(io::const_error!(io::ErrorKind::Unsupported, "lchown not supported by vxworks"))
 }
 
 #[cfg(not(any(target_os = "fuchsia", target_os = "vxworks")))]
@@ -2101,7 +2101,7 @@ pub fn chroot(dir: &Path) -> io::Result<()> {
 #[cfg(target_os = "vxworks")]
 pub fn chroot(dir: &Path) -> io::Result<()> {
     let _ = dir;
-    Err(io::const_io_error!(io::ErrorKind::Unsupported, "chroot not supported by vxworks"))
+    Err(io::const_error!(io::ErrorKind::Unsupported, "chroot not supported by vxworks"))
 }
 
 pub use remove_dir_impl::remove_dir_all;
diff --git a/library/std/src/sys/pal/unix/l4re.rs b/library/std/src/sys/pal/unix/l4re.rs
index 52d39dcfb16..37dd370c514 100644
--- a/library/std/src/sys/pal/unix/l4re.rs
+++ b/library/std/src/sys/pal/unix/l4re.rs
@@ -1,6 +1,6 @@
 macro_rules! unimpl {
     () => {
-        return Err(io::const_io_error!(
+        return Err(io::const_error!(
             io::ErrorKind::Unsupported,
             "No networking available on L4Re.",
         ));
diff --git a/library/std/src/sys/pal/unix/net.rs b/library/std/src/sys/pal/unix/net.rs
index 6a67bb0a101..d140607869c 100644
--- a/library/std/src/sys/pal/unix/net.rs
+++ b/library/std/src/sys/pal/unix/net.rs
@@ -190,7 +190,7 @@ impl Socket {
         loop {
             let elapsed = start.elapsed();
             if elapsed >= timeout {
-                return Err(io::const_io_error!(io::ErrorKind::TimedOut, "connection timed out"));
+                return Err(io::const_error!(io::ErrorKind::TimedOut, "connection timed out"));
             }
 
             let timeout = timeout - elapsed;
@@ -225,7 +225,7 @@ impl Socket {
                         // for POLLHUP or POLLERR rather than read readiness
                         if pollfd.revents & (libc::POLLHUP | libc::POLLERR) != 0 {
                             let e = self.take_error()?.unwrap_or_else(|| {
-                                io::const_io_error!(
+                                io::const_error!(
                                     io::ErrorKind::Uncategorized,
                                     "no error set after POLLHUP",
                                 )
diff --git a/library/std/src/sys/pal/unix/os.rs b/library/std/src/sys/pal/unix/os.rs
index f207131ddf3..789a40c13e6 100644
--- a/library/std/src/sys/pal/unix/os.rs
+++ b/library/std/src/sys/pal/unix/os.rs
@@ -258,7 +258,7 @@ pub fn current_exe() -> io::Result<PathBuf> {
     use crate::env;
     use crate::io::ErrorKind;
 
-    let exe_path = env::args().next().ok_or(io::const_io_error!(
+    let exe_path = env::args().next().ok_or(io::const_error!(
         ErrorKind::NotFound,
         "an executable path was not found because no arguments were provided through argv"
     ))?;
@@ -284,7 +284,7 @@ pub fn current_exe() -> io::Result<PathBuf> {
             }
         }
     }
-    Err(io::const_io_error!(ErrorKind::NotFound, "an executable path was not found"))
+    Err(io::const_error!(ErrorKind::NotFound, "an executable path was not found"))
 }
 
 #[cfg(any(target_os = "freebsd", target_os = "dragonfly"))]
@@ -340,7 +340,7 @@ pub fn current_exe() -> io::Result<PathBuf> {
                 0,
             ))?;
             if path_len <= 1 {
-                return Err(io::const_io_error!(
+                return Err(io::const_error!(
                     io::ErrorKind::Uncategorized,
                     "KERN_PROC_PATHNAME sysctl returned zero-length string",
                 ));
@@ -363,7 +363,7 @@ pub fn current_exe() -> io::Result<PathBuf> {
         if curproc_exe.is_file() {
             return crate::fs::read_link(curproc_exe);
         }
-        Err(io::const_io_error!(
+        Err(io::const_error!(
             io::ErrorKind::Uncategorized,
             "/proc/curproc/exe doesn't point to regular file.",
         ))
@@ -382,10 +382,9 @@ pub fn current_exe() -> io::Result<PathBuf> {
         cvt(libc::sysctl(mib, 4, argv.as_mut_ptr() as *mut _, &mut argv_len, ptr::null_mut(), 0))?;
         argv.set_len(argv_len as usize);
         if argv[0].is_null() {
-            return Err(io::const_io_error!(
-                io::ErrorKind::Uncategorized,
-                "no current exe available",
-            ));
+            return Err(
+                io::const_error!(io::ErrorKind::Uncategorized, "no current exe available",),
+            );
         }
         let argv0 = CStr::from_ptr(argv[0]).to_bytes();
         if argv0[0] == b'.' || argv0.iter().any(|b| *b == b'/') {
@@ -405,7 +404,7 @@ pub fn current_exe() -> io::Result<PathBuf> {
 ))]
 pub fn current_exe() -> io::Result<PathBuf> {
     match crate::fs::read_link("/proc/self/exe") {
-        Err(ref e) if e.kind() == io::ErrorKind::NotFound => Err(io::const_io_error!(
+        Err(ref e) if e.kind() == io::ErrorKind::NotFound => Err(io::const_error!(
             io::ErrorKind::Uncategorized,
             "no /proc/self/exe available. Is /proc mounted?",
         )),
@@ -476,7 +475,7 @@ pub fn current_exe() -> io::Result<PathBuf> {
         );
         if result != libc::B_OK {
             use crate::io::ErrorKind;
-            Err(io::const_io_error!(ErrorKind::Uncategorized, "Error getting executable path"))
+            Err(io::const_error!(ErrorKind::Uncategorized, "Error getting executable path"))
         } else {
             // find_path adds the null terminator.
             let name = CStr::from_ptr(name.as_ptr()).to_bytes();
@@ -493,7 +492,7 @@ pub fn current_exe() -> io::Result<PathBuf> {
 #[cfg(target_os = "l4re")]
 pub fn current_exe() -> io::Result<PathBuf> {
     use crate::io::ErrorKind;
-    Err(io::const_io_error!(ErrorKind::Unsupported, "Not yet implemented!"))
+    Err(io::const_error!(ErrorKind::Unsupported, "Not yet implemented!"))
 }
 
 #[cfg(target_os = "vxworks")]
@@ -523,7 +522,7 @@ pub fn current_exe() -> io::Result<PathBuf> {
     use crate::env;
     use crate::io::ErrorKind;
 
-    let exe_path = env::args().next().ok_or(io::const_io_error!(
+    let exe_path = env::args().next().ok_or(io::const_error!(
         ErrorKind::Uncategorized,
         "an executable path was not found because no arguments were provided through argv"
     ))?;
diff --git a/library/std/src/sys/pal/unix/process/process_fuchsia.rs b/library/std/src/sys/pal/unix/process/process_fuchsia.rs
index 8f7d786e32f..b7a35718757 100644
--- a/library/std/src/sys/pal/unix/process/process_fuchsia.rs
+++ b/library/std/src/sys/pal/unix/process/process_fuchsia.rs
@@ -18,7 +18,7 @@ impl Command {
         let envp = self.capture_env();
 
         if self.saw_nul() {
-            return Err(io::const_io_error!(
+            return Err(io::const_error!(
                 io::ErrorKind::InvalidInput,
                 "nul byte found in provided data",
             ));
@@ -38,7 +38,7 @@ impl Command {
 
     pub fn exec(&mut self, default: Stdio) -> io::Error {
         if self.saw_nul() {
-            return io::const_io_error!(
+            return io::const_error!(
                 io::ErrorKind::InvalidInput,
                 "nul byte found in provided data",
             );
@@ -185,7 +185,7 @@ impl Process {
             ))?;
         }
         if actual != 1 {
-            return Err(io::const_io_error!(
+            return Err(io::const_error!(
                 io::ErrorKind::InvalidData,
                 "Failed to get exit status of process",
             ));
@@ -222,7 +222,7 @@ impl Process {
             ))?;
         }
         if actual != 1 {
-            return Err(io::const_io_error!(
+            return Err(io::const_error!(
                 io::ErrorKind::InvalidData,
                 "Failed to get exit status of process",
             ));
diff --git a/library/std/src/sys/pal/unix/process/process_unix.rs b/library/std/src/sys/pal/unix/process/process_unix.rs
index 8faf1fda546..ec4965c1d71 100644
--- a/library/std/src/sys/pal/unix/process/process_unix.rs
+++ b/library/std/src/sys/pal/unix/process/process_unix.rs
@@ -61,7 +61,7 @@ impl Command {
         let envp = self.capture_env();
 
         if self.saw_nul() {
-            return Err(io::const_io_error!(
+            return Err(io::const_error!(
                 ErrorKind::InvalidInput,
                 "nul byte found in provided data",
             ));
@@ -175,7 +175,7 @@ impl Command {
     // allowed to exist in dead code), but it sounds bad, so we go out of our
     // way to avoid that all-together.
     #[cfg(any(target_os = "tvos", target_os = "watchos"))]
-    const ERR_APPLE_TV_WATCH_NO_FORK_EXEC: Error = io::const_io_error!(
+    const ERR_APPLE_TV_WATCH_NO_FORK_EXEC: Error = io::const_error!(
         ErrorKind::Unsupported,
         "`fork`+`exec`-based process spawning is not supported on this target",
     );
@@ -218,7 +218,7 @@ impl Command {
                 } else if delay < MAX_FORKSPAWN_SLEEP {
                     thread::sleep(delay);
                 } else {
-                    return Err(io::const_io_error!(
+                    return Err(io::const_error!(
                         ErrorKind::WouldBlock,
                         "forking returned EBADF too often",
                     ));
@@ -235,7 +235,7 @@ impl Command {
         let envp = self.capture_env();
 
         if self.saw_nul() {
-            return io::const_io_error!(ErrorKind::InvalidInput, "nul byte found in provided data",);
+            return io::const_error!(ErrorKind::InvalidInput, "nul byte found in provided data",);
         }
 
         match self.setup_io(default, true) {
@@ -561,7 +561,7 @@ impl Command {
                         } else if delay < MAX_FORKSPAWN_SLEEP {
                             thread::sleep(delay);
                         } else {
-                            return Err(io::const_io_error!(
+                            return Err(io::const_error!(
                                 ErrorKind::WouldBlock,
                                 "posix_spawnp returned EBADF too often",
                             ));
diff --git a/library/std/src/sys/pal/unix/process/process_vxworks.rs b/library/std/src/sys/pal/unix/process/process_vxworks.rs
index 38daf6af918..e2c1b6a0326 100644
--- a/library/std/src/sys/pal/unix/process/process_vxworks.rs
+++ b/library/std/src/sys/pal/unix/process/process_vxworks.rs
@@ -22,7 +22,7 @@ impl Command {
         let envp = self.capture_env();
 
         if self.saw_nul() {
-            return Err(io::const_io_error!(
+            return Err(io::const_error!(
                 ErrorKind::InvalidInput,
                 "nul byte found in provided data",
             ));
diff --git a/library/std/src/sys/pal/unix/thread.rs b/library/std/src/sys/pal/unix/thread.rs
index 04024661836..131a6e81b1e 100644
--- a/library/std/src/sys/pal/unix/thread.rs
+++ b/library/std/src/sys/pal/unix/thread.rs
@@ -469,7 +469,7 @@ pub fn available_parallelism() -> io::Result<NonZero<usize>> {
             unsafe {
                 use libc::_syspage_ptr;
                 if _syspage_ptr.is_null() {
-                    Err(io::const_io_error!(io::ErrorKind::NotFound, "No syspage available"))
+                    Err(io::const_error!(io::ErrorKind::NotFound, "No syspage available"))
                 } else {
                     let cpus = (*_syspage_ptr).num_cpu;
                     NonZero::new(cpus as usize)
@@ -509,7 +509,7 @@ pub fn available_parallelism() -> io::Result<NonZero<usize>> {
             }
         } else {
             // FIXME: implement on Redox, l4re
-            Err(io::const_io_error!(io::ErrorKind::Unsupported, "Getting the number of hardware threads is not supported on the target platform"))
+            Err(io::const_error!(io::ErrorKind::Unsupported, "Getting the number of hardware threads is not supported on the target platform"))
         }
     }
 }
diff --git a/library/std/src/sys/pal/unix/time.rs b/library/std/src/sys/pal/unix/time.rs
index 535fe6b27d9..343864d0b3f 100644
--- a/library/std/src/sys/pal/unix/time.rs
+++ b/library/std/src/sys/pal/unix/time.rs
@@ -96,7 +96,7 @@ impl Timespec {
         if tv_nsec >= 0 && tv_nsec < NSEC_PER_SEC as i64 {
             Ok(unsafe { Self::new_unchecked(tv_sec, tv_nsec) })
         } else {
-            Err(io::const_io_error!(io::ErrorKind::InvalidData, "Invalid timestamp"))
+            Err(io::const_error!(io::ErrorKind::InvalidData, "Invalid timestamp"))
         }
     }
 
diff --git a/library/std/src/sys/pal/unsupported/os.rs b/library/std/src/sys/pal/unsupported/os.rs
index 481fd62c04f..48de4312885 100644
--- a/library/std/src/sys/pal/unsupported/os.rs
+++ b/library/std/src/sys/pal/unsupported/os.rs
@@ -96,11 +96,11 @@ pub fn getenv(_: &OsStr) -> Option<OsString> {
 }
 
 pub unsafe fn setenv(_: &OsStr, _: &OsStr) -> io::Result<()> {
-    Err(io::const_io_error!(io::ErrorKind::Unsupported, "cannot set env vars on this platform"))
+    Err(io::const_error!(io::ErrorKind::Unsupported, "cannot set env vars on this platform"))
 }
 
 pub unsafe fn unsetenv(_: &OsStr) -> io::Result<()> {
-    Err(io::const_io_error!(io::ErrorKind::Unsupported, "cannot unset env vars on this platform"))
+    Err(io::const_error!(io::ErrorKind::Unsupported, "cannot unset env vars on this platform"))
 }
 
 pub fn temp_dir() -> PathBuf {
diff --git a/library/std/src/sys/pal/wasi/fs.rs b/library/std/src/sys/pal/wasi/fs.rs
index 3296c762cca..0667eb90101 100644
--- a/library/std/src/sys/pal/wasi/fs.rs
+++ b/library/std/src/sys/pal/wasi/fs.rs
@@ -496,7 +496,7 @@ impl File {
     pub fn set_times(&self, times: FileTimes) -> io::Result<()> {
         let to_timestamp = |time: Option<SystemTime>| match time {
             Some(time) if let Some(ts) = time.to_wasi_timestamp() => Ok(ts),
-            Some(_) => Err(io::const_io_error!(
+            Some(_) => Err(io::const_error!(
                 io::ErrorKind::InvalidInput,
                 "timestamp is too large to set as a file time"
             )),
@@ -764,8 +764,7 @@ fn open_parent(p: &Path) -> io::Result<(ManuallyDrop<WasiFd>, PathBuf)> {
 }
 
 pub fn osstr2str(f: &OsStr) -> io::Result<&str> {
-    f.to_str()
-        .ok_or_else(|| io::const_io_error!(io::ErrorKind::Uncategorized, "input must be utf-8"))
+    f.to_str().ok_or_else(|| io::const_error!(io::ErrorKind::Uncategorized, "input must be utf-8"))
 }
 
 pub fn copy(from: &Path, to: &Path) -> io::Result<u64> {
@@ -811,7 +810,7 @@ fn remove_dir_all_recursive(parent: &WasiFd, path: &Path) -> io::Result<()> {
     for entry in ReadDir::new(fd, dummy_root) {
         let entry = entry?;
         let path = crate::str::from_utf8(&entry.name).map_err(|_| {
-            io::const_io_error!(io::ErrorKind::Uncategorized, "invalid utf-8 file name found")
+            io::const_error!(io::ErrorKind::Uncategorized, "invalid utf-8 file name found")
         })?;
 
         let result: io::Result<()> = try {
diff --git a/library/std/src/sys/pal/wasip2/net.rs b/library/std/src/sys/pal/wasip2/net.rs
index 06e623df843..f009a51821f 100644
--- a/library/std/src/sys/pal/wasip2/net.rs
+++ b/library/std/src/sys/pal/wasip2/net.rs
@@ -117,7 +117,7 @@ impl Socket {
         loop {
             let elapsed = start.elapsed();
             if elapsed >= timeout {
-                return Err(io::const_io_error!(io::ErrorKind::TimedOut, "connection timed out"));
+                return Err(io::const_error!(io::ErrorKind::TimedOut, "connection timed out"));
             }
 
             let timeout = timeout - elapsed;
diff --git a/library/std/src/sys/pal/windows/args.rs b/library/std/src/sys/pal/windows/args.rs
index e9fc19bcb99..3447a0157e4 100644
--- a/library/std/src/sys/pal/windows/args.rs
+++ b/library/std/src/sys/pal/windows/args.rs
@@ -327,7 +327,7 @@ pub(crate) fn make_bat_command_line(
     force_quotes: bool,
 ) -> io::Result<Vec<u16>> {
     const INVALID_ARGUMENT_ERROR: io::Error =
-        io::const_io_error!(io::ErrorKind::InvalidInput, r#"batch file arguments are invalid"#);
+        io::const_error!(io::ErrorKind::InvalidInput, r#"batch file arguments are invalid"#);
     // Set the start of the command line to `cmd.exe /c "`
     // 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
@@ -340,7 +340,7 @@ pub(crate) fn make_bat_command_line(
     // Windows file names cannot contain a `"` character or end with `\\`.
     // If the script name does then return an error.
     if script.contains(&(b'"' as u16)) || script.last() == Some(&(b'\\' as u16)) {
-        return Err(io::const_io_error!(
+        return Err(io::const_error!(
             io::ErrorKind::InvalidInput,
             "Windows file names may not contain `\"` or end with `\\`"
         ));
diff --git a/library/std/src/sys/pal/windows/fs.rs b/library/std/src/sys/pal/windows/fs.rs
index 07e4f93a379..5bdd5f81b9c 100644
--- a/library/std/src/sys/pal/windows/fs.rs
+++ b/library/std/src/sys/pal/windows/fs.rs
@@ -677,7 +677,7 @@ impl File {
                     )
                 }
                 _ => {
-                    return Err(io::const_io_error!(
+                    return Err(io::const_error!(
                         io::ErrorKind::Uncategorized,
                         "Unsupported reparse point type",
                     ));
@@ -718,7 +718,7 @@ impl File {
             || times.modified.map_or(false, is_zero)
             || times.created.map_or(false, is_zero)
         {
-            return Err(io::const_io_error!(
+            return Err(io::const_error!(
                 io::ErrorKind::InvalidInput,
                 "Cannot set file timestamp to 0",
             ));
@@ -728,7 +728,7 @@ impl File {
             || times.modified.map_or(false, is_max)
             || times.created.map_or(false, is_max)
         {
-            return Err(io::const_io_error!(
+            return Err(io::const_error!(
                 io::ErrorKind::InvalidInput,
                 "Cannot set file timestamp to 0xFFFF_FFFF_FFFF_FFFF",
             ));
@@ -1305,10 +1305,9 @@ pub fn link(original: &Path, link: &Path) -> io::Result<()> {
 
 #[cfg(target_vendor = "uwp")]
 pub fn link(_original: &Path, _link: &Path) -> io::Result<()> {
-    return Err(io::const_io_error!(
-        io::ErrorKind::Unsupported,
-        "hard link are not supported on UWP",
-    ));
+    return Err(
+        io::const_error!(io::ErrorKind::Unsupported, "hard link are not supported on UWP",),
+    );
 }
 
 pub fn stat(path: &Path) -> io::Result<FileAttr> {
@@ -1495,7 +1494,7 @@ pub fn junction_point(original: &Path, link: &Path) -> io::Result<()> {
             let bytes = unsafe { OsStr::from_encoded_bytes_unchecked(&abs_path[2..]) };
             r"\??\UNC\".encode_utf16().chain(bytes.encode_wide()).collect()
         } else {
-            return Err(io::const_io_error!(io::ErrorKind::InvalidInput, "path is not valid"));
+            return Err(io::const_error!(io::ErrorKind::InvalidInput, "path is not valid"));
         }
     };
     // Defined inline so we don't have to mess about with variable length buffer.
@@ -1512,10 +1511,7 @@ pub fn junction_point(original: &Path, link: &Path) -> io::Result<()> {
     }
     let data_len = 12 + (abs_path.len() * 2);
     if data_len > u16::MAX as usize {
-        return Err(io::const_io_error!(
-            io::ErrorKind::InvalidInput,
-            "`original` path is too long"
-        ));
+        return Err(io::const_error!(io::ErrorKind::InvalidInput, "`original` path is too long"));
     }
     let data_len = data_len as u16;
     let mut header = MountPointBuffer {
diff --git a/library/std/src/sys/pal/windows/mod.rs b/library/std/src/sys/pal/windows/mod.rs
index aca69490d7a..d66ff15e10b 100644
--- a/library/std/src/sys/pal/windows/mod.rs
+++ b/library/std/src/sys/pal/windows/mod.rs
@@ -183,7 +183,7 @@ pub fn to_u16s<S: AsRef<OsStr>>(s: S) -> crate::io::Result<Vec<u16>> {
         maybe_result.extend(s.encode_wide());
 
         if unrolled_find_u16s(0, &maybe_result).is_some() {
-            return Err(crate::io::const_io_error!(
+            return Err(crate::io::const_error!(
                 ErrorKind::InvalidInput,
                 "strings passed to WinAPI cannot contain NULs",
             ));
diff --git a/library/std/src/sys/pal/windows/net.rs b/library/std/src/sys/pal/windows/net.rs
index fd62d1f407c..a92853c642c 100644
--- a/library/std/src/sys/pal/windows/net.rs
+++ b/library/std/src/sys/pal/windows/net.rs
@@ -267,7 +267,7 @@ impl Socket {
                 };
 
                 match count {
-                    0 => Err(io::const_io_error!(io::ErrorKind::TimedOut, "connection timed out")),
+                    0 => Err(io::const_error!(io::ErrorKind::TimedOut, "connection timed out")),
                     _ => {
                         if writefds.fd_count != 1 {
                             if let Some(e) = self.take_error()? {
diff --git a/library/std/src/sys/pal/windows/process.rs b/library/std/src/sys/pal/windows/process.rs
index 17bb03fe7af..da0daacd1dd 100644
--- a/library/std/src/sys/pal/windows/process.rs
+++ b/library/std/src/sys/pal/windows/process.rs
@@ -144,7 +144,7 @@ impl AsRef<OsStr> for EnvKey {
 
 pub(crate) fn ensure_no_nuls<T: AsRef<OsStr>>(str: T) -> io::Result<T> {
     if str.as_ref().encode_wide().any(|b| b == 0) {
-        Err(io::const_io_error!(ErrorKind::InvalidInput, "nul byte found in provided data"))
+        Err(io::const_error!(ErrorKind::InvalidInput, "nul byte found in provided data"))
     } else {
         Ok(str)
     }
@@ -439,10 +439,9 @@ fn resolve_exe<'a>(
 ) -> io::Result<Vec<u16>> {
     // Early return if there is no filename.
     if exe_path.is_empty() || path::has_trailing_slash(exe_path) {
-        return Err(io::const_io_error!(
-            io::ErrorKind::InvalidInput,
-            "program path has no file name",
-        ));
+        return Err(
+            io::const_error!(io::ErrorKind::InvalidInput, "program path has no file name",),
+        );
     }
     // Test if the file name has the `exe` extension.
     // This does a case-insensitive `ends_with`.
@@ -492,7 +491,7 @@ fn resolve_exe<'a>(
         }
     }
     // If we get here then the executable cannot be found.
-    Err(io::const_io_error!(io::ErrorKind::NotFound, "program not found"))
+    Err(io::const_error!(io::ErrorKind::NotFound, "program not found"))
 }
 
 // Calls `f` for every path that should be used to find an executable.
@@ -921,7 +920,7 @@ fn make_proc_thread_attribute_list(
     // a null pointer to retrieve the required size.
     let mut required_size = 0;
     let Ok(attribute_count) = attributes.len().try_into() else {
-        return Err(io::const_io_error!(
+        return Err(io::const_error!(
             ErrorKind::InvalidInput,
             "maximum number of ProcThreadAttributes exceeded",
         ));
diff --git a/library/std/src/sys/pal/windows/stdio.rs b/library/std/src/sys/pal/windows/stdio.rs
index 575f2250eb9..642c8bc4df7 100644
--- a/library/std/src/sys/pal/windows/stdio.rs
+++ b/library/std/src/sys/pal/windows/stdio.rs
@@ -107,7 +107,7 @@ fn write(handle_id: u32, data: &[u8], incomplete_utf8: &mut IncompleteUtf8) -> i
         if data[0] >> 6 != 0b10 {
             // not a continuation byte - reject
             incomplete_utf8.len = 0;
-            return Err(io::const_io_error!(
+            return Err(io::const_error!(
                 io::ErrorKind::InvalidData,
                 "Windows stdio in console mode does not support writing non-UTF-8 byte sequences",
             ));
@@ -129,7 +129,7 @@ fn write(handle_id: u32, data: &[u8], incomplete_utf8: &mut IncompleteUtf8) -> i
                 return Ok(1);
             }
             Err(_) => {
-                return Err(io::const_io_error!(
+                return Err(io::const_error!(
                     io::ErrorKind::InvalidData,
                     "Windows stdio in console mode does not support writing non-UTF-8 byte sequences",
                 ));
@@ -153,7 +153,7 @@ fn write(handle_id: u32, data: &[u8], incomplete_utf8: &mut IncompleteUtf8) -> i
                 incomplete_utf8.len = 1;
                 return Ok(1);
             } else {
-                return Err(io::const_io_error!(
+                return Err(io::const_error!(
                     io::ErrorKind::InvalidData,
                     "Windows stdio in console mode does not support writing non-UTF-8 byte sequences",
                 ));
@@ -392,7 +392,7 @@ fn utf16_to_utf8(utf16: &[u16], utf8: &mut [u8]) -> io::Result<usize> {
     };
     if result == 0 {
         // We can't really do any better than forget all data and return an error.
-        Err(io::const_io_error!(
+        Err(io::const_error!(
             io::ErrorKind::InvalidData,
             "Windows stdin in console mode does not support non-UTF-16 input; \
             encountered unpaired surrogate",
diff --git a/library/std/src/sys/pal/xous/net/dns.rs b/library/std/src/sys/pal/xous/net/dns.rs
index 1a2b56b4da5..ff6e49ed2d4 100644
--- a/library/std/src/sys/pal/xous/net/dns.rs
+++ b/library/std/src/sys/pal/xous/net/dns.rs
@@ -107,7 +107,7 @@ impl TryFrom<&str> for LookupHost {
             ($e:expr, $msg:expr) => {
                 match $e {
                     Some(r) => r,
-                    None => return Err(io::const_io_error!(io::ErrorKind::InvalidInput, &$msg)),
+                    None => return Err(io::const_error!(io::ErrorKind::InvalidInput, &$msg)),
                 }
             };
         }
@@ -123,7 +123,6 @@ impl TryFrom<(&str, u16)> for LookupHost {
     type Error = io::Error;
 
     fn try_from(v: (&str, u16)) -> io::Result<LookupHost> {
-        lookup(v.0, v.1)
-            .map_err(|_e| io::const_io_error!(io::ErrorKind::InvalidInput, &"DNS failure"))
+        lookup(v.0, v.1).map_err(|_e| io::const_error!(io::ErrorKind::InvalidInput, &"DNS failure"))
     }
 }
diff --git a/library/std/src/sys/pal/xous/net/tcplistener.rs b/library/std/src/sys/pal/xous/net/tcplistener.rs
index ddfb289162b..640a02a64f5 100644
--- a/library/std/src/sys/pal/xous/net/tcplistener.rs
+++ b/library/std/src/sys/pal/xous/net/tcplistener.rs
@@ -9,7 +9,7 @@ use crate::{fmt, io};
 
 macro_rules! unimpl {
     () => {
-        return Err(io::const_io_error!(
+        return Err(io::const_error!(
             io::ErrorKind::Unsupported,
             &"This function is not yet implemented",
         ));
@@ -71,7 +71,7 @@ impl TcpListener {
             0,
             4096,
         ) else {
-            return Err(io::const_io_error!(io::ErrorKind::InvalidInput, &"Invalid response"));
+            return Err(io::const_error!(io::ErrorKind::InvalidInput, &"Invalid response"));
         };
 
         // The first four bytes should be zero upon success, and will be nonzero
@@ -80,16 +80,13 @@ impl TcpListener {
         if response[0] != 0 || valid == 0 {
             let errcode = response[1];
             if errcode == NetError::SocketInUse as u8 {
-                return Err(io::const_io_error!(io::ErrorKind::ResourceBusy, &"Socket in use"));
+                return Err(io::const_error!(io::ErrorKind::ResourceBusy, &"Socket in use"));
             } else if errcode == NetError::Invalid as u8 {
-                return Err(io::const_io_error!(
-                    io::ErrorKind::AddrNotAvailable,
-                    &"Invalid address"
-                ));
+                return Err(io::const_error!(io::ErrorKind::AddrNotAvailable, &"Invalid address"));
             } else if errcode == NetError::LibraryError as u8 {
-                return Err(io::const_io_error!(io::ErrorKind::Other, &"Library error"));
+                return Err(io::const_error!(io::ErrorKind::Other, &"Library error"));
             } else {
-                return Err(io::const_io_error!(
+                return Err(io::const_error!(
                     io::ErrorKind::Other,
                     &"Unable to connect or internal error"
                 ));
@@ -130,16 +127,15 @@ impl TcpListener {
             if receive_request.raw[0] != 0 {
                 // error case
                 if receive_request.raw[1] == NetError::TimedOut as u8 {
-                    return Err(io::const_io_error!(io::ErrorKind::TimedOut, &"accept timed out",));
+                    return Err(io::const_error!(io::ErrorKind::TimedOut, &"accept timed out",));
                 } else if receive_request.raw[1] == NetError::WouldBlock as u8 {
-                    return Err(io::const_io_error!(
-                        io::ErrorKind::WouldBlock,
-                        &"accept would block",
-                    ));
+                    return Err(
+                        io::const_error!(io::ErrorKind::WouldBlock, &"accept would block",),
+                    );
                 } else if receive_request.raw[1] == NetError::LibraryError as u8 {
-                    return Err(io::const_io_error!(io::ErrorKind::Other, &"Library error"));
+                    return Err(io::const_error!(io::ErrorKind::Other, &"Library error"));
                 } else {
-                    return Err(io::const_io_error!(io::ErrorKind::Other, &"library error",));
+                    return Err(io::const_error!(io::ErrorKind::Other, &"library error",));
                 }
             } else {
                 // accept successful
@@ -163,7 +159,7 @@ impl TcpListener {
                         port,
                     )
                 } else {
-                    return Err(io::const_io_error!(io::ErrorKind::Other, &"library error",));
+                    return Err(io::const_error!(io::ErrorKind::Other, &"library error",));
                 };
 
                 // replenish the listener
@@ -175,7 +171,7 @@ impl TcpListener {
                 Ok((TcpStream::from_listener(stream_fd, self.local.port(), port, addr), addr))
             }
         } else {
-            Err(io::const_io_error!(io::ErrorKind::InvalidInput, &"Unable to accept"))
+            Err(io::const_error!(io::ErrorKind::InvalidInput, &"Unable to accept"))
         }
     }
 
@@ -192,7 +188,7 @@ impl TcpListener {
             services::net_server(),
             services::NetBlockingScalar::StdSetTtlTcp(self.fd.load(Ordering::Relaxed), ttl).into(),
         )
-        .or(Err(io::const_io_error!(io::ErrorKind::InvalidInput, &"Unexpected return value")))
+        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, &"Unexpected return value")))
         .map(|_| ())
     }
 
@@ -201,7 +197,7 @@ impl TcpListener {
             services::net_server(),
             services::NetBlockingScalar::StdGetTtlTcp(self.fd.load(Ordering::Relaxed)).into(),
         )
-        .or(Err(io::const_io_error!(io::ErrorKind::InvalidInput, &"Unexpected return value")))
+        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, &"Unexpected return value")))
         .map(|res| res[0] as _)?)
     }
 
diff --git a/library/std/src/sys/pal/xous/net/tcpstream.rs b/library/std/src/sys/pal/xous/net/tcpstream.rs
index 03442cf2fcd..572dd6b3b63 100644
--- a/library/std/src/sys/pal/xous/net/tcpstream.rs
+++ b/library/std/src/sys/pal/xous/net/tcpstream.rs
@@ -10,7 +10,7 @@ use crate::time::Duration;
 
 macro_rules! unimpl {
     () => {
-        return Err(io::const_io_error!(
+        return Err(io::const_error!(
             io::ErrorKind::Unsupported,
             &"This function is not yet implemented",
         ));
@@ -96,7 +96,7 @@ impl TcpStream {
             0,
             4096,
         ) else {
-            return Err(io::const_io_error!(io::ErrorKind::InvalidInput, &"Invalid response"));
+            return Err(io::const_error!(io::ErrorKind::InvalidInput, &"Invalid response"));
         };
 
         // The first four bytes should be zero upon success, and will be nonzero
@@ -106,14 +106,11 @@ impl TcpStream {
             // errcode is a u8 but stuck in a u16 where the upper byte is invalid. Mask & decode accordingly.
             let errcode = response[0];
             if errcode == NetError::SocketInUse as u8 {
-                return Err(io::const_io_error!(io::ErrorKind::ResourceBusy, &"Socket in use",));
+                return Err(io::const_error!(io::ErrorKind::ResourceBusy, &"Socket in use",));
             } else if errcode == NetError::Unaddressable as u8 {
-                return Err(io::const_io_error!(
-                    io::ErrorKind::AddrNotAvailable,
-                    &"Invalid address",
-                ));
+                return Err(io::const_error!(io::ErrorKind::AddrNotAvailable, &"Invalid address",));
             } else {
-                return Err(io::const_io_error!(
+                return Err(io::const_error!(
                     io::ErrorKind::InvalidInput,
                     &"Unable to connect or internal error",
                 ));
@@ -199,7 +196,7 @@ impl TcpStream {
             self.read_timeout.load(Ordering::Relaxed) as usize,
             data_to_read,
         ) else {
-            return Err(io::const_io_error!(
+            return Err(io::const_error!(
                 io::ErrorKind::InvalidInput,
                 &"Library failure: wrong message type or messaging error"
             ));
@@ -215,14 +212,14 @@ impl TcpStream {
             if result[0] != 0 {
                 if result[1] == 8 {
                     // timed out
-                    return Err(io::const_io_error!(io::ErrorKind::TimedOut, &"Timeout",));
+                    return Err(io::const_error!(io::ErrorKind::TimedOut, &"Timeout",));
                 }
                 if result[1] == 9 {
                     // would block
-                    return Err(io::const_io_error!(io::ErrorKind::WouldBlock, &"Would block",));
+                    return Err(io::const_error!(io::ErrorKind::WouldBlock, &"Would block",));
                 }
             }
-            Err(io::const_io_error!(io::ErrorKind::Other, &"recv_slice failure"))
+            Err(io::const_error!(io::ErrorKind::Other, &"recv_slice failure"))
         }
     }
 
@@ -261,23 +258,20 @@ impl TcpStream {
             self.write_timeout.load(Ordering::Relaxed) as usize,
             buf_len,
         )
-        .or(Err(io::const_io_error!(io::ErrorKind::InvalidInput, &"Internal error")))?;
+        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, &"Internal error")))?;
 
         if send_request.raw[0] != 0 {
             if send_request.raw[4] == 8 {
                 // timed out
-                return Err(io::const_io_error!(
+                return Err(io::const_error!(
                     io::ErrorKind::BrokenPipe,
                     &"Timeout or connection closed",
                 ));
             } else if send_request.raw[4] == 9 {
                 // would block
-                return Err(io::const_io_error!(io::ErrorKind::WouldBlock, &"Would block",));
+                return Err(io::const_error!(io::ErrorKind::WouldBlock, &"Would block",));
             } else {
-                return Err(io::const_io_error!(
-                    io::ErrorKind::InvalidInput,
-                    &"Error when sending",
-                ));
+                return Err(io::const_error!(io::ErrorKind::InvalidInput, &"Error when sending",));
             }
         }
         Ok(u32::from_le_bytes([
@@ -310,7 +304,7 @@ impl TcpStream {
             0,
             0,
         ) else {
-            return Err(io::const_io_error!(io::ErrorKind::InvalidInput, &"Internal error"));
+            return Err(io::const_error!(io::ErrorKind::InvalidInput, &"Internal error"));
         };
         let mut i = get_addr.raw.iter();
         match *i.next().unwrap() {
@@ -330,7 +324,7 @@ impl TcpStream {
                 }
                 Ok(SocketAddr::V6(SocketAddrV6::new(new_addr.into(), self.local_port, 0, 0)))
             }
-            _ => Err(io::const_io_error!(io::ErrorKind::InvalidInput, &"Internal error")),
+            _ => Err(io::const_error!(io::ErrorKind::InvalidInput, &"Internal error")),
         }
     }
 
@@ -339,7 +333,7 @@ impl TcpStream {
             services::net_server(),
             services::NetBlockingScalar::StdTcpStreamShutdown(self.fd, how).into(),
         )
-        .or(Err(io::const_io_error!(io::ErrorKind::InvalidInput, &"Unexpected return value")))
+        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, &"Unexpected return value")))
         .map(|_| ())
     }
 
@@ -361,7 +355,7 @@ impl TcpStream {
             services::net_server(),
             services::NetBlockingScalar::StdSetNodelay(self.fd, enabled).into(),
         )
-        .or(Err(io::const_io_error!(io::ErrorKind::InvalidInput, &"Unexpected return value")))
+        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, &"Unexpected return value")))
         .map(|_| ())
     }
 
@@ -370,7 +364,7 @@ impl TcpStream {
             services::net_server(),
             services::NetBlockingScalar::StdGetNodelay(self.fd).into(),
         )
-        .or(Err(io::const_io_error!(io::ErrorKind::InvalidInput, &"Unexpected return value")))
+        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, &"Unexpected return value")))
         .map(|res| res[0] != 0)?)
     }
 
@@ -382,7 +376,7 @@ impl TcpStream {
             services::net_server(),
             services::NetBlockingScalar::StdSetTtlTcp(self.fd, ttl).into(),
         )
-        .or(Err(io::const_io_error!(io::ErrorKind::InvalidInput, &"Unexpected return value")))
+        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, &"Unexpected return value")))
         .map(|_| ())
     }
 
@@ -391,7 +385,7 @@ impl TcpStream {
             services::net_server(),
             services::NetBlockingScalar::StdGetTtlTcp(self.fd).into(),
         )
-        .or(Err(io::const_io_error!(io::ErrorKind::InvalidInput, &"Unexpected return value")))
+        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, &"Unexpected return value")))
         .map(|res| res[0] as _)?)
     }
 
diff --git a/library/std/src/sys/pal/xous/net/udp.rs b/library/std/src/sys/pal/xous/net/udp.rs
index de5133280ba..1b7ecac6d3a 100644
--- a/library/std/src/sys/pal/xous/net/udp.rs
+++ b/library/std/src/sys/pal/xous/net/udp.rs
@@ -11,7 +11,7 @@ use crate::{fmt, io};
 
 macro_rules! unimpl {
     () => {
-        return Err(io::const_io_error!(
+        return Err(io::const_error!(
             io::ErrorKind::Unsupported,
             &"This function is not yet implemented",
         ));
@@ -72,16 +72,16 @@ impl UdpSocket {
             if response[0] != 0 || valid == 0 {
                 let errcode = response[1];
                 if errcode == NetError::SocketInUse as u8 {
-                    return Err(io::const_io_error!(io::ErrorKind::ResourceBusy, &"Socket in use"));
+                    return Err(io::const_error!(io::ErrorKind::ResourceBusy, &"Socket in use"));
                 } else if errcode == NetError::Invalid as u8 {
-                    return Err(io::const_io_error!(
+                    return Err(io::const_error!(
                         io::ErrorKind::InvalidInput,
                         &"Port can't be 0 or invalid address"
                     ));
                 } else if errcode == NetError::LibraryError as u8 {
-                    return Err(io::const_io_error!(io::ErrorKind::Other, &"Library error"));
+                    return Err(io::const_error!(io::ErrorKind::Other, &"Library error"));
                 } else {
-                    return Err(io::const_io_error!(
+                    return Err(io::const_error!(
                         io::ErrorKind::Other,
                         &"Unable to connect or internal error"
                     ));
@@ -98,13 +98,13 @@ impl UdpSocket {
                 nonblocking: Cell::new(false),
             });
         }
-        Err(io::const_io_error!(io::ErrorKind::InvalidInput, &"Invalid response"))
+        Err(io::const_error!(io::ErrorKind::InvalidInput, &"Invalid response"))
     }
 
     pub fn peer_addr(&self) -> io::Result<SocketAddr> {
         match self.remote.get() {
             Some(dest) => Ok(dest),
-            None => Err(io::const_io_error!(io::ErrorKind::NotConnected, &"No peer specified")),
+            None => Err(io::const_error!(io::ErrorKind::NotConnected, &"No peer specified")),
         }
     }
 
@@ -141,16 +141,13 @@ impl UdpSocket {
             if receive_request.raw[0] != 0 {
                 // error case
                 if receive_request.raw[1] == NetError::TimedOut as u8 {
-                    return Err(io::const_io_error!(io::ErrorKind::TimedOut, &"recv timed out",));
+                    return Err(io::const_error!(io::ErrorKind::TimedOut, &"recv timed out",));
                 } else if receive_request.raw[1] == NetError::WouldBlock as u8 {
-                    return Err(io::const_io_error!(
-                        io::ErrorKind::WouldBlock,
-                        &"recv would block",
-                    ));
+                    return Err(io::const_error!(io::ErrorKind::WouldBlock, &"recv would block",));
                 } else if receive_request.raw[1] == NetError::LibraryError as u8 {
-                    return Err(io::const_io_error!(io::ErrorKind::Other, &"Library error"));
+                    return Err(io::const_error!(io::ErrorKind::Other, &"Library error"));
                 } else {
-                    return Err(io::const_io_error!(io::ErrorKind::Other, &"library error",));
+                    return Err(io::const_error!(io::ErrorKind::Other, &"library error",));
                 }
             } else {
                 let rr = &receive_request.raw;
@@ -173,7 +170,7 @@ impl UdpSocket {
                         port,
                     )
                 } else {
-                    return Err(io::const_io_error!(io::ErrorKind::Other, &"library error",));
+                    return Err(io::const_error!(io::ErrorKind::Other, &"library error",));
                 };
                 for (&s, d) in rr[22..22 + rxlen as usize].iter().zip(buf.iter_mut()) {
                     *d = s;
@@ -181,7 +178,7 @@ impl UdpSocket {
                 Ok((rxlen as usize, addr))
             }
         } else {
-            Err(io::const_io_error!(io::ErrorKind::InvalidInput, &"Unable to recv"))
+            Err(io::const_error!(io::ErrorKind::InvalidInput, &"Unable to recv"))
         }
     }
 
@@ -211,7 +208,7 @@ impl UdpSocket {
         if let Some(addr) = self.remote.get() {
             self.send_to(buf, &addr)
         } else {
-            Err(io::const_io_error!(io::ErrorKind::NotConnected, &"No remote specified"))
+            Err(io::const_error!(io::ErrorKind::NotConnected, &"No remote specified"))
         }
     }
 
@@ -282,22 +279,19 @@ impl UdpSocket {
                     if response[0] != 0 || valid == 0 {
                         let errcode = response[1];
                         if errcode == NetError::SocketInUse as u8 {
-                            return Err(io::const_io_error!(
+                            return Err(io::const_error!(
                                 io::ErrorKind::ResourceBusy,
                                 &"Socket in use"
                             ));
                         } else if errcode == NetError::Invalid as u8 {
-                            return Err(io::const_io_error!(
+                            return Err(io::const_error!(
                                 io::ErrorKind::InvalidInput,
                                 &"Socket not valid"
                             ));
                         } else if errcode == NetError::LibraryError as u8 {
-                            return Err(io::const_io_error!(
-                                io::ErrorKind::Other,
-                                &"Library error"
-                            ));
+                            return Err(io::const_error!(io::ErrorKind::Other, &"Library error"));
                         } else {
-                            return Err(io::const_io_error!(
+                            return Err(io::const_error!(
                                 io::ErrorKind::Other,
                                 &"Unable to connect"
                             ));
@@ -309,7 +303,7 @@ impl UdpSocket {
                 }
                 Err(crate::os::xous::ffi::Error::ServerQueueFull) => {
                     if now.elapsed() >= write_timeout {
-                        return Err(io::const_io_error!(
+                        return Err(io::const_error!(
                             io::ErrorKind::WouldBlock,
                             &"Write timed out"
                         ));
@@ -318,7 +312,7 @@ impl UdpSocket {
                         crate::thread::yield_now();
                     }
                 }
-                _ => return Err(io::const_io_error!(io::ErrorKind::Other, &"Library error")),
+                _ => return Err(io::const_error!(io::ErrorKind::Other, &"Library error")),
             }
         }
     }
@@ -372,7 +366,7 @@ impl UdpSocket {
             services::net_server(),
             services::NetBlockingScalar::StdSetTtlUdp(self.fd, ttl).into(),
         )
-        .or(Err(io::const_io_error!(io::ErrorKind::InvalidInput, &"Unexpected return value")))
+        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, &"Unexpected return value")))
         .map(|_| ())
     }
 
@@ -381,7 +375,7 @@ impl UdpSocket {
             services::net_server(),
             services::NetBlockingScalar::StdGetTtlUdp(self.fd).into(),
         )
-        .or(Err(io::const_io_error!(io::ErrorKind::InvalidInput, &"Unexpected return value")))
+        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, &"Unexpected return value")))
         .map(|res| res[0] as _)?)
     }
 
diff --git a/library/std/src/sys/pal/zkvm/os.rs b/library/std/src/sys/pal/zkvm/os.rs
index 5d224ffd1ba..868b19e33b6 100644
--- a/library/std/src/sys/pal/zkvm/os.rs
+++ b/library/std/src/sys/pal/zkvm/os.rs
@@ -115,11 +115,11 @@ pub fn getenv(varname: &OsStr) -> Option<OsString> {
 }
 
 pub unsafe fn setenv(_: &OsStr, _: &OsStr) -> io::Result<()> {
-    Err(io::const_io_error!(io::ErrorKind::Unsupported, "cannot set env vars on this platform"))
+    Err(io::const_error!(io::ErrorKind::Unsupported, "cannot set env vars on this platform"))
 }
 
 pub unsafe fn unsetenv(_: &OsStr) -> io::Result<()> {
-    Err(io::const_io_error!(io::ErrorKind::Unsupported, "cannot unset env vars on this platform"))
+    Err(io::const_error!(io::ErrorKind::Unsupported, "cannot unset env vars on this platform"))
 }
 
 pub fn temp_dir() -> PathBuf {
diff --git a/library/std/src/sys/path/windows.rs b/library/std/src/sys/path/windows.rs
index 9267602cb97..de042fa3f82 100644
--- a/library/std/src/sys/path/windows.rs
+++ b/library/std/src/sys/path/windows.rs
@@ -328,7 +328,7 @@ pub(crate) fn absolute(path: &Path) -> io::Result<PathBuf> {
     if prefix.map(|x| x.is_verbatim()).unwrap_or(false) {
         // NULs in verbatim paths are rejected for consistency.
         if path.as_encoded_bytes().contains(&0) {
-            return Err(io::const_io_error!(
+            return Err(io::const_error!(
                 io::ErrorKind::InvalidInput,
                 "strings passed to WinAPI cannot contain NULs",
             ));
diff --git a/library/std/src/sys_common/fs.rs b/library/std/src/sys_common/fs.rs
index a25a7244660..bfd684d295b 100644
--- a/library/std/src/sys_common/fs.rs
+++ b/library/std/src/sys_common/fs.rs
@@ -5,7 +5,7 @@ use crate::io::{self, Error, ErrorKind};
 use crate::path::Path;
 use crate::sys_common::ignore_notfound;
 
-pub(crate) const NOT_FILE_ERROR: Error = io::const_io_error!(
+pub(crate) const NOT_FILE_ERROR: Error = io::const_error!(
     ErrorKind::InvalidInput,
     "the source path is neither a regular file nor a symlink to a regular file",
 );
diff --git a/library/std/src/sys_common/net.rs b/library/std/src/sys_common/net.rs
index 5a0ad907581..74306978d22 100644
--- a/library/std/src/sys_common/net.rs
+++ b/library/std/src/sys_common/net.rs
@@ -122,7 +122,7 @@ pub fn sockaddr_to_addr(storage: &c::sockaddr_storage, len: usize) -> io::Result
                 *(storage as *const _ as *const c::sockaddr_in6)
             })))
         }
-        _ => Err(io::const_io_error!(ErrorKind::InvalidInput, "invalid argument")),
+        _ => Err(io::const_error!(ErrorKind::InvalidInput, "invalid argument")),
     }
 }
 
@@ -185,7 +185,7 @@ impl TryFrom<&str> for LookupHost {
             ($e:expr, $msg:expr) => {
                 match $e {
                     Some(r) => r,
-                    None => return Err(io::const_io_error!(io::ErrorKind::InvalidInput, $msg)),
+                    None => return Err(io::const_error!(io::ErrorKind::InvalidInput, $msg)),
                 }
             };
         }
diff --git a/license-metadata.json b/license-metadata.json
new file mode 100644
index 00000000000..09cc3693565
--- /dev/null
+++ b/license-metadata.json
@@ -0,0 +1,269 @@
+{
+  "files": {
+    "children": [
+      {
+        "children": [
+          {
+            "children": [
+              {
+                "children": [
+                  {
+                    "children": [
+                      {
+                        "directories": [],
+                        "files": [
+                          "analyzer-decls.h",
+                          "malloc-macro.h"
+                        ],
+                        "license": {
+                          "copyright": [
+                            "2000-2024 Free Software Foundation, Inc"
+                          ],
+                          "spdx": "GPL-2.0-only"
+                        },
+                        "type": "group"
+                      }
+                    ],
+                    "license": {
+                      "copyright": [
+                        "2007-2011 Atheros Communications Inc",
+                        "2011-2012,2017 Qualcomm Atheros, Inc",
+                        "2016-2017 Erik Stromdahl <erik.stromdahl@gmail.com>"
+                      ],
+                      "spdx": "ISC"
+                    },
+                    "name": "c-c++-common/analyzer",
+                    "type": "directory"
+                  }
+                ],
+                "license": {
+                  "copyright": [
+                    "2000-2024 Free Software Foundation, Inc"
+                  ],
+                  "spdx": "GPL-2.0-only"
+                },
+                "name": "gcc/testsuite",
+                "type": "directory"
+              },
+              {
+                "license": {
+                  "copyright": [
+                    "2000-2024 Free Software Foundation, Inc"
+                  ],
+                  "spdx": "GCC-exception-3.1"
+                },
+                "name": "libstdc++-v3/config/os/aix/os_defines.h",
+                "type": "file"
+              }
+            ],
+            "license": {
+              "copyright": [
+                "1997-2024 Free Software Foundation, Inc"
+              ],
+              "spdx": "GPL-3.0-or-later"
+            },
+            "name": "src/gcc",
+            "type": "directory"
+          },
+          {
+            "children": [
+              {
+                "license": {
+                  "copyright": [
+                    "The Rust Project Developers (see https://thanks.rust-lang.org)"
+                  ],
+                  "spdx": "Apache-2.0 OR MIT"
+                },
+                "name": "noscript.css",
+                "type": "file"
+              },
+              {
+                "license": {
+                  "copyright": [
+                    "Nicolas Gallagher and Jonathan Neal"
+                  ],
+                  "spdx": "MIT"
+                },
+                "name": "normalize.css",
+                "type": "file"
+              }
+            ],
+            "license": {
+              "copyright": [
+                "2016 Ike Ku, Jessica Stokes and Leon Guan",
+                "The Rust Project Developers (see https://thanks.rust-lang.org)"
+              ],
+              "spdx": "Apache-2.0 OR MIT"
+            },
+            "name": "src/librustdoc/html/static/css",
+            "type": "directory"
+          },
+          {
+            "children": [
+              {
+                "license": {
+                  "copyright": [
+                    "The Rust Project Developers (see https://thanks.rust-lang.org)"
+                  ],
+                  "spdx": "Apache-2.0 OR MIT"
+                },
+                "name": "README.txt",
+                "type": "file"
+              },
+              {
+                "directories": [],
+                "files": [
+                  "FiraSans-LICENSE.txt",
+                  "FiraSans-Medium.woff2",
+                  "FiraSans-Regular.woff2"
+                ],
+                "license": {
+                  "copyright": [
+                    "2014, Mozilla Foundation",
+                    "2014, Telefonica S.A"
+                  ],
+                  "spdx": "OFL-1.1"
+                },
+                "type": "group"
+              },
+              {
+                "directories": [],
+                "files": [
+                  "NanumBarunGothic-LICENSE.txt",
+                  "NanumBarunGothic.ttf.woff2"
+                ],
+                "license": {
+                  "copyright": [
+                    "2010 NAVER Corporation"
+                  ],
+                  "spdx": "OFL-1.1"
+                },
+                "type": "group"
+              }
+            ],
+            "license": {
+              "copyright": [
+                "2010, 2012, 2014-2023, Adobe Systems Incorporated"
+              ],
+              "spdx": "OFL-1.1"
+            },
+            "name": "src/librustdoc/html/static/fonts",
+            "type": "directory"
+          },
+          {
+            "license": {
+              "copyright": [
+                "2003-2019 University of Illinois at Urbana-Champaign",
+                "The Rust Project Developers (see https://thanks.rust-lang.org)"
+              ],
+              "spdx": "Apache-2.0 WITH LLVM-exception AND (Apache-2.0 OR MIT)"
+            },
+            "name": "compiler/rustc_llvm/llvm-wrapper/SymbolWrapper.cpp",
+            "type": "file"
+          },
+          {
+            "children": [],
+            "license": {
+              "copyright": [
+                "2014 Alex Crichton",
+                "The Rust Project Developers (see https://thanks.rust-lang.org)"
+              ],
+              "spdx": "Apache-2.0 OR MIT"
+            },
+            "name": "library/backtrace",
+            "type": "directory"
+          },
+          {
+            "license": {
+              "copyright": [
+                "1991-2024 Unicode, Inc"
+              ],
+              "spdx": "Unicode-3.0"
+            },
+            "name": "library/core/src/unicode/unicode_data.rs",
+            "type": "file"
+          },
+          {
+            "children": [],
+            "license": {
+              "copyright": [
+                "2019 The Crossbeam Project Developers",
+                "The Rust Project Developers (see https://thanks.rust-lang.org)"
+              ],
+              "spdx": "Apache-2.0 OR MIT"
+            },
+            "name": "library/std/src/sync/mpmc",
+            "type": "directory"
+          },
+          {
+            "license": {
+              "copyright": [
+                "2016 The Fuchsia Authors",
+                "The Rust Project Developers (see https://thanks.rust-lang.org)"
+              ],
+              "spdx": "BSD-2-Clause AND (Apache-2.0 OR MIT)"
+            },
+            "name": "library/std/src/sys/sync/mutex/fuchsia.rs",
+            "type": "file"
+          },
+          {
+            "children": [],
+            "license": {
+              "copyright": [
+                "Rust on Embedded Devices Working Group",
+                "The Rust Project Developers (see https://thanks.rust-lang.org)"
+              ],
+              "spdx": "Apache-2.0 OR CC-BY-SA-4.0 OR MIT"
+            },
+            "name": "src/doc/embedded-book",
+            "type": "directory"
+          },
+          {
+            "children": [],
+            "license": {
+              "copyright": [
+                "2014 Jorge Aparicio",
+                "The Rust Project Developers (see https://thanks.rust-lang.org)"
+              ],
+              "spdx": "Apache-2.0 OR MIT"
+            },
+            "name": "src/doc/rust-by-example",
+            "type": "directory"
+          },
+          {
+            "license": {
+              "copyright": [
+                "2014-2021 Knut Sveidqvist"
+              ],
+              "spdx": "MIT"
+            },
+            "name": "src/doc/rustc-dev-guide/mermaid.min.js",
+            "type": "file"
+          },
+          {
+            "children": [],
+            "license": {
+              "copyright": [
+                "2003-2019 University of Illinois at Urbana-Champaign",
+                "2003-2019 by the contributors listed in CREDITS.TXT (https://github.com/rust-lang/llvm-project/blob/7738295178045041669876bf32b0543ec8319a5c/llvm/CREDITS.TXT)",
+                "2010 Apple Inc"
+              ],
+              "spdx": "Apache-2.0 WITH LLVM-exception AND NCSA"
+            },
+            "name": "src/llvm-project",
+            "type": "directory"
+          }
+        ],
+        "license": {
+          "copyright": [
+            "The Rust Project Developers (see https://thanks.rust-lang.org)"
+          ],
+          "spdx": "Apache-2.0 OR MIT"
+        },
+        "name": ".",
+        "type": "directory"
+      }
+    ],
+    "type": "root"
+  }
+}
\ No newline at end of file
diff --git a/src/bootstrap/src/core/build_steps/run.rs b/src/bootstrap/src/core/build_steps/run.rs
index 1a0a90564e6..c76504761be 100644
--- a/src/bootstrap/src/core/build_steps/run.rs
+++ b/src/bootstrap/src/core/build_steps/run.rs
@@ -181,8 +181,7 @@ impl Step for CollectLicenseMetadata {
             panic!("REUSE is required to collect the license metadata");
         };
 
-        // Temporary location, it will be moved to src/etc once it's accurate.
-        let dest = builder.out.join("license-metadata.json");
+        let dest = builder.src.join("license-metadata.json");
 
         let mut cmd = builder.tool_cmd(Tool::CollectLicenseMetadata);
         cmd.env("REUSE_EXE", reuse);
@@ -209,8 +208,7 @@ impl Step for GenerateCopyright {
     }
 
     fn run(self, builder: &Builder<'_>) -> Self::Output {
-        let license_metadata = builder.ensure(CollectLicenseMetadata);
-
+        let license_metadata = builder.src.join("license-metadata.json");
         let dest = builder.out.join("COPYRIGHT.html");
         let dest_libstd = builder.out.join("COPYRIGHT-library.html");
 
diff --git a/src/bootstrap/src/core/build_steps/test.rs b/src/bootstrap/src/core/build_steps/test.rs
index 1cabd1c39f1..dd967bca867 100644
--- a/src/bootstrap/src/core/build_steps/test.rs
+++ b/src/bootstrap/src/core/build_steps/test.rs
@@ -3469,7 +3469,6 @@ impl Step for CodegenCranelift {
             // FIXME remove once vendoring is handled
             .arg("--skip-test")
             .arg("testsuite.extended_sysroot");
-        cargo.args(builder.config.test_args());
 
         cargo.into_cmd().run(builder);
     }
@@ -3664,14 +3663,42 @@ impl Step for TestFloatParse {
             &[],
         );
 
-        cargo_run.arg("--");
-        if builder.config.args().is_empty() {
-            // By default, exclude tests that take longer than ~1m.
-            cargo_run.arg("--skip-huge");
-        } else {
-            cargo_run.args(builder.config.args());
+        if !matches!(env::var("FLOAT_PARSE_TESTS_NO_SKIP_HUGE").as_deref(), Ok("1") | Ok("true")) {
+            cargo_run.args(["--", "--skip-huge"]);
         }
 
         cargo_run.into_cmd().run(builder);
     }
 }
+
+#[derive(Debug, PartialOrd, Ord, Clone, Hash, PartialEq, Eq)]
+pub struct CollectLicenseMetadata;
+
+impl Step for CollectLicenseMetadata {
+    type Output = PathBuf;
+    const ONLY_HOSTS: bool = true;
+
+    fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
+        run.path("src/tools/collect-license-metadata")
+    }
+
+    fn make_run(run: RunConfig<'_>) {
+        run.builder.ensure(CollectLicenseMetadata);
+    }
+
+    fn run(self, builder: &Builder<'_>) -> Self::Output {
+        let Some(reuse) = &builder.config.reuse else {
+            panic!("REUSE is required to collect the license metadata");
+        };
+
+        let dest = builder.src.join("license-metadata.json");
+
+        let mut cmd = builder.tool_cmd(Tool::CollectLicenseMetadata);
+        cmd.env("REUSE_EXE", reuse);
+        cmd.env("DEST", &dest);
+        cmd.env("ONLY_CHECK", "1");
+        cmd.run(builder);
+
+        dest
+    }
+}
diff --git a/src/bootstrap/src/core/builder/mod.rs b/src/bootstrap/src/core/builder/mod.rs
index d59e0fa7288..e6902bb8cee 100644
--- a/src/bootstrap/src/core/builder/mod.rs
+++ b/src/bootstrap/src/core/builder/mod.rs
@@ -915,6 +915,7 @@ impl<'a> Builder<'a> {
                 test::HtmlCheck,
                 test::RustInstaller,
                 test::TestFloatParse,
+                test::CollectLicenseMetadata,
                 // Run bootstrap close to the end as it's unlikely to fail
                 test::Bootstrap,
                 // Run run-make last, since these won't pass without make on Windows
diff --git a/src/ci/docker/host-x86_64/mingw-check/Dockerfile b/src/ci/docker/host-x86_64/mingw-check/Dockerfile
index f0afb570cc4..d408cd518a0 100644
--- a/src/ci/docker/host-x86_64/mingw-check/Dockerfile
+++ b/src/ci/docker/host-x86_64/mingw-check/Dockerfile
@@ -63,6 +63,7 @@ ENV SCRIPT \
            /scripts/validate-toolstate.sh && \
            /scripts/validate-error-codes.sh && \
            reuse --include-submodules lint && \
+           python3 ../x.py test collect-license-metadata && \
            # Runs checks to ensure that there are no issues in our JS code.
            es-check es2019 ../src/librustdoc/html/static/js/*.js && \
            eslint -c ../src/librustdoc/html/static/.eslintrc.js ../src/librustdoc/html/static/js/*.js && \
diff --git a/src/ci/github-actions/jobs.yml b/src/ci/github-actions/jobs.yml
index 9a51a3f4268..2f59892acf6 100644
--- a/src/ci/github-actions/jobs.yml
+++ b/src/ci/github-actions/jobs.yml
@@ -48,7 +48,7 @@ runners:
 
 envs:
   env-x86_64-apple-tests: &env-x86_64-apple-tests
-    SCRIPT: ./x.py --stage 2 test --skip tests/ui --skip tests/rustdoc
+    SCRIPT: ./x.py --stage 2 test --skip tests/ui --skip tests/rustdoc -- --exact
     RUST_CONFIGURE_ARGS: --build=x86_64-apple-darwin --enable-sanitizers --enable-profiler --set rust.jemalloc
     RUSTC_RETRY_LINKER_ON_SEGFAULT: 1
     MACOSX_DEPLOYMENT_TARGET: 10.12
@@ -384,13 +384,12 @@ auto:
       SCRIPT: make ci-msvc
     <<: *job-windows-8c
 
-  - image: x86_64-msvc-ext
+  # x86_64-msvc-ext is split into multiple jobs to run tests in parallel.
+  - image: x86_64-msvc-ext1
     env:
-      SCRIPT: python x.py --stage 2 test src/tools/cargotest src/tools/cargo && src/ci/docker/host-x86_64/x86_64-gnu-tools/checktools.sh x.py /tmp/toolstate/toolstates.json windows
-      HOST_TARGET: x86_64-pc-windows-msvc
-      RUST_CONFIGURE_ARGS: --build=x86_64-pc-windows-msvc --enable-lld --save-toolstates=/tmp/toolstate/toolstates.json
-      DEPLOY_TOOLSTATES_JSON: toolstates-windows.json
-    <<: *job-windows-8c
+      SCRIPT: python x.py --stage 2 test src/tools/cargotest src/tools/cargo
+      RUST_CONFIGURE_ARGS: --build=x86_64-pc-windows-msvc --enable-lld
+    <<: *job-windows
 
   # Temporary builder to workaround CI issues
   # See <https://github.com/rust-lang/rust/issues/127883>
@@ -406,6 +405,15 @@ auto:
       RUST_CONFIGURE_ARGS: --build=x86_64-pc-windows-msvc --enable-lld
     <<: *job-windows
 
+  # Run `checktools.sh` and upload the toolstate file.
+  - image: x86_64-msvc-ext3
+    env:
+      SCRIPT: src/ci/docker/host-x86_64/x86_64-gnu-tools/checktools.sh x.py /tmp/toolstate/toolstates.json windows
+      HOST_TARGET: x86_64-pc-windows-msvc
+      RUST_CONFIGURE_ARGS: --build=x86_64-pc-windows-msvc --enable-lld --save-toolstates=/tmp/toolstate/toolstates.json
+      DEPLOY_TOOLSTATES_JSON: toolstates-windows.json
+    <<: *job-windows
+
   # 32/64-bit MinGW builds.
   #
   # We are using MinGW with POSIX threads since LLVM requires
diff --git a/src/tools/collect-license-metadata/src/main.rs b/src/tools/collect-license-metadata/src/main.rs
index dce36bb17b6..08a30d0b899 100644
--- a/src/tools/collect-license-metadata/src/main.rs
+++ b/src/tools/collect-license-metadata/src/main.rs
@@ -4,7 +4,7 @@ mod reuse;
 
 use std::path::PathBuf;
 
-use anyhow::Error;
+use anyhow::{Context, Error};
 
 use crate::licenses::LicensesInterner;
 
@@ -12,10 +12,12 @@ use crate::licenses::LicensesInterner;
 ///
 /// You should probably let `bootstrap` execute this program instead of running it directly.
 ///
-/// Run `x.py run collect-license-metadata`
+/// * Run `x.py run collect-license-metadata` to re-regenerate the file.
+/// * Run `x.py test collect-license-metadata` to check if the file you have is correct.
 fn main() -> Result<(), Error> {
     let reuse_exe: PathBuf = std::env::var_os("REUSE_EXE").expect("Missing REUSE_EXE").into();
     let dest: PathBuf = std::env::var_os("DEST").expect("Missing DEST").into();
+    let only_check = std::env::var_os("ONLY_CHECK").is_some();
 
     let mut interner = LicensesInterner::new();
     let paths = crate::reuse::collect(&reuse_exe, &mut interner)?;
@@ -23,15 +25,32 @@ fn main() -> Result<(), Error> {
     let mut tree = crate::path_tree::build(paths);
     tree.simplify();
 
-    if let Some(parent) = dest.parent() {
-        std::fs::create_dir_all(parent)?;
+    let output = serde_json::json!({
+        "files": crate::path_tree::expand_interned_licenses(tree, &interner)
+    });
+
+    if only_check {
+        println!("loading existing license information");
+        let existing = std::fs::read_to_string(&dest).with_context(|| {
+            format!("Failed to read existing license JSON at {}", dest.display())
+        })?;
+        let existing_json: serde_json::Value =
+            serde_json::from_str(&existing).with_context(|| {
+                format!("Failed to read existing license JSON at {}", dest.display())
+            })?;
+        if existing_json != output {
+            eprintln!("The existing {} file is out of date.", dest.display());
+            eprintln!("Run ./x run collect-license-metadata to update it.");
+            anyhow::bail!("The existing {} file doesn't match what REUSE reports.", dest.display());
+        }
+        println!("license information matches");
+    } else {
+        if let Some(parent) = dest.parent() {
+            std::fs::create_dir_all(parent)?;
+        }
+        std::fs::write(&dest, &serde_json::to_vec_pretty(&output)?)?;
+        println!("license information written to {}", dest.display());
     }
-    std::fs::write(
-        &dest,
-        &serde_json::to_vec_pretty(&serde_json::json!({
-            "files": crate::path_tree::expand_interned_licenses(tree, &interner),
-        }))?,
-    )?;
 
     Ok(())
 }
diff --git a/src/tools/collect-license-metadata/src/reuse.rs b/src/tools/collect-license-metadata/src/reuse.rs
index e5ee8f0da5e..dbe46781b7c 100644
--- a/src/tools/collect-license-metadata/src/reuse.rs
+++ b/src/tools/collect-license-metadata/src/reuse.rs
@@ -10,10 +10,10 @@ pub(crate) fn collect(
     reuse_exe: &Path,
     interner: &mut LicensesInterner,
 ) -> Result<Vec<(PathBuf, LicenseId)>, Error> {
-    eprintln!("gathering license information from REUSE");
+    println!("gathering license information from REUSE (this might take a minute...)");
     let start = Instant::now();
     let raw = &obtain_spdx_document(reuse_exe)?;
-    eprintln!("finished gathering the license information from REUSE in {:.2?}", start.elapsed());
+    println!("finished gathering the license information from REUSE in {:.2?}", start.elapsed());
 
     let document = spdx_rs::parsers::spdx_from_tag_value(&raw)?;
 
diff --git a/src/tools/generate-copyright/src/main.rs b/src/tools/generate-copyright/src/main.rs
index f9d96b59462..f83d16d0cab 100644
--- a/src/tools/generate-copyright/src/main.rs
+++ b/src/tools/generate-copyright/src/main.rs
@@ -57,6 +57,10 @@ fn main() -> Result<(), Error> {
         dependencies: collected_cargo_metadata,
     };
     let output = template.render()?;
+    // Git stores text files with \n, but this file may contain \r\n in files
+    // copied from dependencies. Normalise them before we write them out, for
+    // consistency.
+    let output = output.replace("\r\n", "\n");
     std::fs::write(&dest_file, output)?;
 
     // Output libstd subset file
@@ -65,6 +69,10 @@ fn main() -> Result<(), Error> {
         dependencies: library_collected_cargo_metadata,
     };
     let output = template.render()?;
+    // Git stores text files with \n, but this file may contain \r\n in files
+    // copied from dependencies. Normalise them before we write them out, for
+    // consistency.
+    let output = output.replace("\r\n", "\n");
     std::fs::write(&libstd_dest_file, output)?;
 
     Ok(())
diff --git a/src/tools/miri/src/shims/windows/foreign_items.rs b/src/tools/miri/src/shims/windows/foreign_items.rs
index c145cf3ceb8..a1fad6f9af4 100644
--- a/src/tools/miri/src/shims/windows/foreign_items.rs
+++ b/src/tools/miri/src/shims/windows/foreign_items.rs
@@ -382,6 +382,14 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
                 // Return success (`1`).
                 this.write_int(1, dest)?;
             }
+            "TlsFree" => {
+                let [key] = this.check_shim(abi, ExternAbi::System { unwind: false }, link_name, args)?;
+                let key = u128::from(this.read_scalar(key)?.to_u32()?);
+                this.machine.tls.delete_tls_key(key)?;
+
+                // Return success (`1`).
+                this.write_int(1, dest)?;
+            }
 
             // Access to command-line arguments
             "GetCommandLineW" => {
diff --git a/src/tools/miri/tests/pass/tls/windows-tls.rs b/src/tools/miri/tests/pass/tls/windows-tls.rs
new file mode 100644
index 00000000000..58131be1903
--- /dev/null
+++ b/src/tools/miri/tests/pass/tls/windows-tls.rs
@@ -0,0 +1,18 @@
+//@only-target: windows # this directly tests windows-only functions
+
+use std::ffi::c_void;
+use std::ptr;
+
+extern "system" {
+    fn TlsAlloc() -> u32;
+    fn TlsSetValue(key: u32, val: *mut c_void) -> bool;
+    fn TlsGetValue(key: u32) -> *mut c_void;
+    fn TlsFree(key: u32) -> bool;
+}
+
+fn main() {
+    let key = unsafe { TlsAlloc() };
+    assert!(unsafe { TlsSetValue(key, ptr::without_provenance_mut(1)) });
+    assert_eq!(unsafe { TlsGetValue(key).addr() }, 1);
+    assert!(unsafe { TlsFree(key) });
+}
diff --git a/tests/crashes/129444.rs b/tests/crashes/129444.rs
deleted file mode 100644
index b1b547b5191..00000000000
--- a/tests/crashes/129444.rs
+++ /dev/null
@@ -1,15 +0,0 @@
-//@ known-bug: rust-lang/rust#129444
-
-//@ compile-flags: -Znext-solver=coherence
-
-trait Trait {
-    type Assoc;
-}
-
-struct W<T: Trait>(*mut T);
-impl<T: ?Trait> Trait for W<W<W<T>>> {}
-
-trait NoOverlap {}
-impl<T: Trait<W<T>>> NoOverlap for T {}
-
-impl<T: Trait<Assoc = u32>> NoOverlap for W<T> {}
diff --git a/tests/ui/coherence/fuzzing/best-obligation-ICE.rs b/tests/ui/coherence/fuzzing/best-obligation-ICE.rs
new file mode 100644
index 00000000000..49f40b579d4
--- /dev/null
+++ b/tests/ui/coherence/fuzzing/best-obligation-ICE.rs
@@ -0,0 +1,20 @@
+// A regression test for #129444. This previously ICE'd as
+// computing the best obligation for one ambiguous obligation
+// added spurious inference constraints which caused another
+// candidate to pass.
+trait Trait {
+    type Assoc;
+}
+
+struct W<T: Trait>(*mut T);
+impl<T> Trait for W<W<W<T>>> {}
+//~^ ERROR the trait bound `W<W<T>>: Trait` is not satisfied
+//~| ERROR the trait bound `W<T>: Trait` is not satisfied
+//~| ERROR the trait bound `T: Trait` is not satisfied
+//~| ERROR not all trait items implemented, missing: `Assoc`
+
+trait NoOverlap {}
+impl<T: Trait> NoOverlap for T {}
+impl<T: Trait<Assoc = u32>> NoOverlap for W<T> {}
+//~^ ERROR conflicting implementations of trait `NoOverlap` for type `W<W<W<W<_>>>>`
+fn main() {}
diff --git a/tests/ui/coherence/fuzzing/best-obligation-ICE.stderr b/tests/ui/coherence/fuzzing/best-obligation-ICE.stderr
new file mode 100644
index 00000000000..88de8023f6d
--- /dev/null
+++ b/tests/ui/coherence/fuzzing/best-obligation-ICE.stderr
@@ -0,0 +1,69 @@
+error[E0277]: the trait bound `W<W<T>>: Trait` is not satisfied
+  --> $DIR/best-obligation-ICE.rs:10:19
+   |
+LL | impl<T> Trait for W<W<W<T>>> {}
+   |                   ^^^^^^^^^^ the trait `Trait` is not implemented for `W<W<T>>`
+   |
+note: required by a bound in `W`
+  --> $DIR/best-obligation-ICE.rs:9:13
+   |
+LL | struct W<T: Trait>(*mut T);
+   |             ^^^^^ required by this bound in `W`
+help: consider introducing a `where` clause, but there might be an alternative better way to express this requirement
+   |
+LL | impl<T> Trait for W<W<W<T>>> where W<W<T>>: Trait {}
+   |                              ++++++++++++++++++++
+
+error[E0277]: the trait bound `W<T>: Trait` is not satisfied
+  --> $DIR/best-obligation-ICE.rs:10:19
+   |
+LL | impl<T> Trait for W<W<W<T>>> {}
+   |                   ^^^^^^^^^^ the trait `Trait` is not implemented for `W<T>`
+   |
+note: required by a bound in `W`
+  --> $DIR/best-obligation-ICE.rs:9:13
+   |
+LL | struct W<T: Trait>(*mut T);
+   |             ^^^^^ required by this bound in `W`
+help: consider introducing a `where` clause, but there might be an alternative better way to express this requirement
+   |
+LL | impl<T> Trait for W<W<W<T>>> where W<T>: Trait {}
+   |                              +++++++++++++++++
+
+error[E0277]: the trait bound `T: Trait` is not satisfied
+  --> $DIR/best-obligation-ICE.rs:10:19
+   |
+LL | impl<T> Trait for W<W<W<T>>> {}
+   |                   ^^^^^^^^^^ the trait `Trait` is not implemented for `T`
+   |
+note: required by a bound in `W`
+  --> $DIR/best-obligation-ICE.rs:9:13
+   |
+LL | struct W<T: Trait>(*mut T);
+   |             ^^^^^ required by this bound in `W`
+help: consider restricting type parameter `T`
+   |
+LL | impl<T: Trait> Trait for W<W<W<T>>> {}
+   |       +++++++
+
+error[E0046]: not all trait items implemented, missing: `Assoc`
+  --> $DIR/best-obligation-ICE.rs:10:1
+   |
+LL |     type Assoc;
+   |     ---------- `Assoc` from trait
+...
+LL | impl<T> Trait for W<W<W<T>>> {}
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ missing `Assoc` in implementation
+
+error[E0119]: conflicting implementations of trait `NoOverlap` for type `W<W<W<W<_>>>>`
+  --> $DIR/best-obligation-ICE.rs:18:1
+   |
+LL | impl<T: Trait> NoOverlap for T {}
+   | ------------------------------ first implementation here
+LL | impl<T: Trait<Assoc = u32>> NoOverlap for W<T> {}
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `W<W<W<W<_>>>>`
+
+error: aborting due to 5 previous errors
+
+Some errors have detailed explanations: E0046, E0119, E0277.
+For more information about an error, try `rustc --explain E0046`.
diff --git a/tests/ui/impl-trait/unsized_coercion.next.stderr b/tests/ui/impl-trait/unsized_coercion.next.stderr
index 4cebd26a5be..bea5ddb0aef 100644
--- a/tests/ui/impl-trait/unsized_coercion.next.stderr
+++ b/tests/ui/impl-trait/unsized_coercion.next.stderr
@@ -1,35 +1,11 @@
 error[E0277]: the size for values of type `dyn Trait` cannot be known at compilation time
-  --> $DIR/unsized_coercion.rs:15:17
+  --> $DIR/unsized_coercion.rs:14:17
    |
 LL |         let x = hello();
    |                 ^^^^^^^ doesn't have a size known at compile-time
    |
    = help: the trait `Sized` is not implemented for `dyn Trait`
 
-error[E0308]: mismatched types
-  --> $DIR/unsized_coercion.rs:19:5
-   |
-LL | fn hello() -> Box<impl Trait> {
-   |               ---------------
-   |               |   |
-   |               |   the expected opaque type
-   |               expected `Box<impl Trait>` because of return type
-...
-LL |     Box::new(1u32)
-   |     ^^^^^^^^^^^^^^ types differ
-   |
-   = note: expected struct `Box<impl Trait>`
-              found struct `Box<u32>`
-
-error[E0277]: the size for values of type `dyn Trait` cannot be known at compilation time
-  --> $DIR/unsized_coercion.rs:12:1
-   |
-LL | fn hello() -> Box<impl Trait> {
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ doesn't have a size known at compile-time
-   |
-   = help: the trait `Sized` is not implemented for `dyn Trait`
-
-error: aborting due to 3 previous errors
+error: aborting due to 1 previous error
 
-Some errors have detailed explanations: E0277, E0308.
-For more information about an error, try `rustc --explain E0277`.
+For more information about this error, try `rustc --explain E0277`.
diff --git a/tests/ui/impl-trait/unsized_coercion.rs b/tests/ui/impl-trait/unsized_coercion.rs
index b3791b38abc..2cbf0d25d7e 100644
--- a/tests/ui/impl-trait/unsized_coercion.rs
+++ b/tests/ui/impl-trait/unsized_coercion.rs
@@ -10,13 +10,12 @@ trait Trait {}
 impl Trait for u32 {}
 
 fn hello() -> Box<impl Trait> {
-    //[next]~^ ERROR the size for values of type `dyn Trait` cannot be known at compilation time
     if true {
         let x = hello();
         //[next]~^ ERROR: the size for values of type `dyn Trait` cannot be known at compilation time
         let y: Box<dyn Trait> = x;
     }
-    Box::new(1u32) //[next]~ ERROR: mismatched types
+    Box::new(1u32)
 }
 
 fn main() {}
diff --git a/tests/ui/impl-trait/unsized_coercion3.next.stderr b/tests/ui/impl-trait/unsized_coercion3.next.stderr
index d1e1809cf16..28771e01813 100644
--- a/tests/ui/impl-trait/unsized_coercion3.next.stderr
+++ b/tests/ui/impl-trait/unsized_coercion3.next.stderr
@@ -1,35 +1,11 @@
 error[E0277]: the trait bound `dyn Send: Trait` is not satisfied
-  --> $DIR/unsized_coercion3.rs:14:17
+  --> $DIR/unsized_coercion3.rs:13:17
    |
 LL |         let x = hello();
    |                 ^^^^^^^ the trait `Trait` is not implemented for `dyn Send`
    |
    = help: the trait `Trait` is implemented for `u32`
 
-error[E0308]: mismatched types
-  --> $DIR/unsized_coercion3.rs:19:5
-   |
-LL | fn hello() -> Box<impl Trait + ?Sized> {
-   |               ------------------------
-   |               |   |
-   |               |   the expected opaque type
-   |               expected `Box<impl Trait + ?Sized>` because of return type
-...
-LL |     Box::new(1u32)
-   |     ^^^^^^^^^^^^^^ types differ
-   |
-   = note: expected struct `Box<impl Trait + ?Sized>`
-              found struct `Box<u32>`
-
-error[E0277]: the trait bound `dyn Send: Trait` is not satisfied
-  --> $DIR/unsized_coercion3.rs:11:1
-   |
-LL | fn hello() -> Box<impl Trait + ?Sized> {
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `Trait` is not implemented for `dyn Send`
-   |
-   = help: the trait `Trait` is implemented for `u32`
-
-error: aborting due to 3 previous errors
+error: aborting due to 1 previous error
 
-Some errors have detailed explanations: E0277, E0308.
-For more information about an error, try `rustc --explain E0277`.
+For more information about this error, try `rustc --explain E0277`.
diff --git a/tests/ui/impl-trait/unsized_coercion3.old.stderr b/tests/ui/impl-trait/unsized_coercion3.old.stderr
index 3bb9f9c2095..52a72b84a8d 100644
--- a/tests/ui/impl-trait/unsized_coercion3.old.stderr
+++ b/tests/ui/impl-trait/unsized_coercion3.old.stderr
@@ -1,5 +1,5 @@
 error[E0277]: the size for values of type `impl Trait + ?Sized` cannot be known at compilation time
-  --> $DIR/unsized_coercion3.rs:16:32
+  --> $DIR/unsized_coercion3.rs:15:32
    |
 LL |         let y: Box<dyn Send> = x;
    |                                ^ doesn't have a size known at compile-time
diff --git a/tests/ui/impl-trait/unsized_coercion3.rs b/tests/ui/impl-trait/unsized_coercion3.rs
index c1dd5350e22..ebfbb2955de 100644
--- a/tests/ui/impl-trait/unsized_coercion3.rs
+++ b/tests/ui/impl-trait/unsized_coercion3.rs
@@ -9,7 +9,6 @@ trait Trait {}
 impl Trait for u32 {}
 
 fn hello() -> Box<impl Trait + ?Sized> {
-    //[next]~^ ERROR: the trait bound `dyn Send: Trait` is not satisfied
     if true {
         let x = hello();
         //[next]~^ ERROR: the trait bound `dyn Send: Trait` is not satisfied
@@ -17,7 +16,6 @@ fn hello() -> Box<impl Trait + ?Sized> {
         //[old]~^ ERROR: the size for values of type `impl Trait + ?Sized` cannot be know
     }
     Box::new(1u32)
-    //[next]~^ ERROR: mismatched types
 }
 
 fn main() {}
diff --git a/tests/ui/traits/negative-bounds/opaque-type-unsatisfied-bound.rs b/tests/ui/traits/negative-bounds/opaque-type-unsatisfied-bound.rs
index 1260cca5106..cbd591eec96 100644
--- a/tests/ui/traits/negative-bounds/opaque-type-unsatisfied-bound.rs
+++ b/tests/ui/traits/negative-bounds/opaque-type-unsatisfied-bound.rs
@@ -14,13 +14,7 @@ fn main() {
 
 fn weird0() -> impl Sized + !Sized {}
 //~^ ERROR the trait bound `(): !Sized` is not satisfied
-//~| ERROR the trait bound `(): !Sized` is not satisfied
-//~| ERROR the trait bound `(): !Sized` is not satisfied
 fn weird1() -> impl !Sized + Sized {}
 //~^ ERROR the trait bound `(): !Sized` is not satisfied
-//~| ERROR the trait bound `(): !Sized` is not satisfied
-//~| ERROR the trait bound `(): !Sized` is not satisfied
 fn weird2() -> impl !Sized {}
 //~^ ERROR the trait bound `(): !Sized` is not satisfied
-//~| ERROR the trait bound `(): !Sized` is not satisfied
-//~| ERROR the trait bound `(): !Sized` is not satisfied
diff --git a/tests/ui/traits/negative-bounds/opaque-type-unsatisfied-bound.stderr b/tests/ui/traits/negative-bounds/opaque-type-unsatisfied-bound.stderr
index 4ec578a3b7b..3dad6d534fd 100644
--- a/tests/ui/traits/negative-bounds/opaque-type-unsatisfied-bound.stderr
+++ b/tests/ui/traits/negative-bounds/opaque-type-unsatisfied-bound.stderr
@@ -5,53 +5,17 @@ LL | fn weird0() -> impl Sized + !Sized {}
    |                ^^^^^^^^^^^^^^^^^^^ the trait bound `(): !Sized` is not satisfied
 
 error[E0277]: the trait bound `(): !Sized` is not satisfied
-  --> $DIR/opaque-type-unsatisfied-bound.rs:15:36
-   |
-LL | fn weird0() -> impl Sized + !Sized {}
-   |                                    ^^ the trait bound `(): !Sized` is not satisfied
-
-error[E0277]: the trait bound `(): !Sized` is not satisfied
-  --> $DIR/opaque-type-unsatisfied-bound.rs:15:1
-   |
-LL | fn weird0() -> impl Sized + !Sized {}
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait bound `(): !Sized` is not satisfied
-
-error[E0277]: the trait bound `(): !Sized` is not satisfied
-  --> $DIR/opaque-type-unsatisfied-bound.rs:19:16
+  --> $DIR/opaque-type-unsatisfied-bound.rs:17:16
    |
 LL | fn weird1() -> impl !Sized + Sized {}
    |                ^^^^^^^^^^^^^^^^^^^ the trait bound `(): !Sized` is not satisfied
 
 error[E0277]: the trait bound `(): !Sized` is not satisfied
-  --> $DIR/opaque-type-unsatisfied-bound.rs:19:36
-   |
-LL | fn weird1() -> impl !Sized + Sized {}
-   |                                    ^^ the trait bound `(): !Sized` is not satisfied
-
-error[E0277]: the trait bound `(): !Sized` is not satisfied
-  --> $DIR/opaque-type-unsatisfied-bound.rs:19:1
-   |
-LL | fn weird1() -> impl !Sized + Sized {}
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait bound `(): !Sized` is not satisfied
-
-error[E0277]: the trait bound `(): !Sized` is not satisfied
-  --> $DIR/opaque-type-unsatisfied-bound.rs:23:16
+  --> $DIR/opaque-type-unsatisfied-bound.rs:19:16
    |
 LL | fn weird2() -> impl !Sized {}
    |                ^^^^^^^^^^^ the trait bound `(): !Sized` is not satisfied
 
-error[E0277]: the trait bound `(): !Sized` is not satisfied
-  --> $DIR/opaque-type-unsatisfied-bound.rs:23:28
-   |
-LL | fn weird2() -> impl !Sized {}
-   |                            ^^ the trait bound `(): !Sized` is not satisfied
-
-error[E0277]: the trait bound `(): !Sized` is not satisfied
-  --> $DIR/opaque-type-unsatisfied-bound.rs:23:1
-   |
-LL | fn weird2() -> impl !Sized {}
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait bound `(): !Sized` is not satisfied
-
 error[E0277]: the trait bound `impl !Trait: Trait` is not satisfied
   --> $DIR/opaque-type-unsatisfied-bound.rs:12:13
    |
@@ -66,6 +30,6 @@ note: required by a bound in `consume`
 LL | fn consume(_: impl Trait) {}
    |                    ^^^^^ required by this bound in `consume`
 
-error: aborting due to 10 previous errors
+error: aborting due to 4 previous errors
 
 For more information about this error, try `rustc --explain E0277`.
diff --git a/tests/ui/traits/negative-bounds/opaque-type-unsatisfied-fn-bound.rs b/tests/ui/traits/negative-bounds/opaque-type-unsatisfied-fn-bound.rs
index c6826578658..39422914afc 100644
--- a/tests/ui/traits/negative-bounds/opaque-type-unsatisfied-fn-bound.rs
+++ b/tests/ui/traits/negative-bounds/opaque-type-unsatisfied-fn-bound.rs
@@ -4,7 +4,5 @@
 
 fn produce() -> impl !Fn<(u32,)> {}
 //~^ ERROR the trait bound `(): !Fn(u32)` is not satisfied
-//~| ERROR the trait bound `(): !Fn(u32)` is not satisfied
-//~| ERROR the trait bound `(): !Fn(u32)` is not satisfied
 
 fn main() {}
diff --git a/tests/ui/traits/negative-bounds/opaque-type-unsatisfied-fn-bound.stderr b/tests/ui/traits/negative-bounds/opaque-type-unsatisfied-fn-bound.stderr
index f81f0a23ac3..760e5aa62f2 100644
--- a/tests/ui/traits/negative-bounds/opaque-type-unsatisfied-fn-bound.stderr
+++ b/tests/ui/traits/negative-bounds/opaque-type-unsatisfied-fn-bound.stderr
@@ -4,18 +4,6 @@ error[E0277]: the trait bound `(): !Fn(u32)` is not satisfied
 LL | fn produce() -> impl !Fn<(u32,)> {}
    |                 ^^^^^^^^^^^^^^^^ the trait bound `(): !Fn(u32)` is not satisfied
 
-error[E0277]: the trait bound `(): !Fn(u32)` is not satisfied
-  --> $DIR/opaque-type-unsatisfied-fn-bound.rs:5:34
-   |
-LL | fn produce() -> impl !Fn<(u32,)> {}
-   |                                  ^^ the trait bound `(): !Fn(u32)` is not satisfied
-
-error[E0277]: the trait bound `(): !Fn(u32)` is not satisfied
-  --> $DIR/opaque-type-unsatisfied-fn-bound.rs:5:1
-   |
-LL | fn produce() -> impl !Fn<(u32,)> {}
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait bound `(): !Fn(u32)` is not satisfied
-
-error: aborting due to 3 previous errors
+error: aborting due to 1 previous error
 
 For more information about this error, try `rustc --explain E0277`.