From 2aa8a1d45cd65c0bb8b3ae7cbf78bfb27440b1ec Mon Sep 17 00:00:00 2001
From: joboet <jonasboettiger@icloud.com>
Date: Tue, 28 Mar 2023 12:10:53 +0200
Subject: [PATCH 1/8] std: make `ReentrantLock` public

---
 library/std/src/io/stdio.rs                   |  45 ++-
 library/std/src/sync/mod.rs                   |   5 +-
 library/std/src/sync/reentrant_lock.rs        | 320 ++++++++++++++++++
 .../sync/{remutex => reentrant_lock}/tests.rs |  34 +-
 library/std/src/sync/remutex.rs               | 178 ----------
 5 files changed, 375 insertions(+), 207 deletions(-)
 create mode 100644 library/std/src/sync/reentrant_lock.rs
 rename library/std/src/sync/{remutex => reentrant_lock}/tests.rs (53%)
 delete mode 100644 library/std/src/sync/remutex.rs

diff --git a/library/std/src/io/stdio.rs b/library/std/src/io/stdio.rs
index 261b570dee74f..455de6d98bae6 100644
--- a/library/std/src/io/stdio.rs
+++ b/library/std/src/io/stdio.rs
@@ -11,8 +11,9 @@ use crate::fs::File;
 use crate::io::{
     self, BorrowedCursor, BufReader, IoSlice, IoSliceMut, LineWriter, Lines, SpecReadByte,
 };
+use crate::panic::{RefUnwindSafe, UnwindSafe};
 use crate::sync::atomic::{AtomicBool, Ordering};
-use crate::sync::{Arc, Mutex, MutexGuard, OnceLock, ReentrantMutex, ReentrantMutexGuard};
+use crate::sync::{Arc, Mutex, MutexGuard, OnceLock, ReentrantLock, ReentrantLockGuard};
 use crate::sys::stdio;
 
 type LocalStream = Arc<Mutex<Vec<u8>>>;
@@ -545,7 +546,7 @@ pub struct Stdout {
     // FIXME: this should be LineWriter or BufWriter depending on the state of
     //        stdout (tty or not). Note that if this is not line buffered it
     //        should also flush-on-panic or some form of flush-on-abort.
-    inner: &'static ReentrantMutex<RefCell<LineWriter<StdoutRaw>>>,
+    inner: &'static ReentrantLock<RefCell<LineWriter<StdoutRaw>>>,
 }
 
 /// A locked reference to the [`Stdout`] handle.
@@ -567,10 +568,10 @@ pub struct Stdout {
 #[must_use = "if unused stdout will immediately unlock"]
 #[stable(feature = "rust1", since = "1.0.0")]
 pub struct StdoutLock<'a> {
-    inner: ReentrantMutexGuard<'a, RefCell<LineWriter<StdoutRaw>>>,
+    inner: ReentrantLockGuard<'a, RefCell<LineWriter<StdoutRaw>>>,
 }
 
-static STDOUT: OnceLock<ReentrantMutex<RefCell<LineWriter<StdoutRaw>>>> = OnceLock::new();
+static STDOUT: OnceLock<ReentrantLock<RefCell<LineWriter<StdoutRaw>>>> = OnceLock::new();
 
 /// Constructs a new handle to the standard output of the current process.
 ///
@@ -624,7 +625,7 @@ static STDOUT: OnceLock<ReentrantMutex<RefCell<LineWriter<StdoutRaw>>>> = OnceLo
 pub fn stdout() -> Stdout {
     Stdout {
         inner: STDOUT
-            .get_or_init(|| ReentrantMutex::new(RefCell::new(LineWriter::new(stdout_raw())))),
+            .get_or_init(|| ReentrantLock::new(RefCell::new(LineWriter::new(stdout_raw())))),
     }
 }
 
@@ -635,7 +636,7 @@ pub fn cleanup() {
     let mut initialized = false;
     let stdout = STDOUT.get_or_init(|| {
         initialized = true;
-        ReentrantMutex::new(RefCell::new(LineWriter::with_capacity(0, stdout_raw())))
+        ReentrantLock::new(RefCell::new(LineWriter::with_capacity(0, stdout_raw())))
     });
 
     if !initialized {
@@ -678,6 +679,12 @@ impl Stdout {
     }
 }
 
+#[stable(feature = "catch_unwind", since = "1.9.0")]
+impl UnwindSafe for Stdout {}
+
+#[stable(feature = "catch_unwind", since = "1.9.0")]
+impl RefUnwindSafe for Stdout {}
+
 #[stable(feature = "std_debug", since = "1.16.0")]
 impl fmt::Debug for Stdout {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
@@ -737,6 +744,12 @@ impl Write for &Stdout {
     }
 }
 
+#[stable(feature = "catch_unwind", since = "1.9.0")]
+impl UnwindSafe for StdoutLock<'_> {}
+
+#[stable(feature = "catch_unwind", since = "1.9.0")]
+impl RefUnwindSafe for StdoutLock<'_> {}
+
 #[stable(feature = "rust1", since = "1.0.0")]
 impl Write for StdoutLock<'_> {
     fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
@@ -786,7 +799,7 @@ impl fmt::Debug for StdoutLock<'_> {
 /// standard library or via raw Windows API calls, will fail.
 #[stable(feature = "rust1", since = "1.0.0")]
 pub struct Stderr {
-    inner: &'static ReentrantMutex<RefCell<StderrRaw>>,
+    inner: &'static ReentrantLock<RefCell<StderrRaw>>,
 }
 
 /// A locked reference to the [`Stderr`] handle.
@@ -808,7 +821,7 @@ pub struct Stderr {
 #[must_use = "if unused stderr will immediately unlock"]
 #[stable(feature = "rust1", since = "1.0.0")]
 pub struct StderrLock<'a> {
-    inner: ReentrantMutexGuard<'a, RefCell<StderrRaw>>,
+    inner: ReentrantLockGuard<'a, RefCell<StderrRaw>>,
 }
 
 /// Constructs a new handle to the standard error of the current process.
@@ -862,8 +875,8 @@ pub fn stderr() -> Stderr {
     // Note that unlike `stdout()` we don't use `at_exit` here to register a
     // destructor. Stderr is not buffered, so there's no need to run a
     // destructor for flushing the buffer
-    static INSTANCE: ReentrantMutex<RefCell<StderrRaw>> =
-        ReentrantMutex::new(RefCell::new(stderr_raw()));
+    static INSTANCE: ReentrantLock<RefCell<StderrRaw>> =
+        ReentrantLock::new(RefCell::new(stderr_raw()));
 
     Stderr { inner: &INSTANCE }
 }
@@ -898,6 +911,12 @@ impl Stderr {
     }
 }
 
+#[stable(feature = "catch_unwind", since = "1.9.0")]
+impl UnwindSafe for Stderr {}
+
+#[stable(feature = "catch_unwind", since = "1.9.0")]
+impl RefUnwindSafe for Stderr {}
+
 #[stable(feature = "std_debug", since = "1.16.0")]
 impl fmt::Debug for Stderr {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
@@ -957,6 +976,12 @@ impl Write for &Stderr {
     }
 }
 
+#[stable(feature = "catch_unwind", since = "1.9.0")]
+impl UnwindSafe for StderrLock<'_> {}
+
+#[stable(feature = "catch_unwind", since = "1.9.0")]
+impl RefUnwindSafe for StderrLock<'_> {}
+
 #[stable(feature = "rust1", since = "1.0.0")]
 impl Write for StderrLock<'_> {
     fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
diff --git a/library/std/src/sync/mod.rs b/library/std/src/sync/mod.rs
index f6a7c0a9f7549..31def978b0feb 100644
--- a/library/std/src/sync/mod.rs
+++ b/library/std/src/sync/mod.rs
@@ -180,7 +180,8 @@ pub use self::lazy_lock::LazyLock;
 #[stable(feature = "once_cell", since = "1.70.0")]
 pub use self::once_lock::OnceLock;
 
-pub(crate) use self::remutex::{ReentrantMutex, ReentrantMutexGuard};
+#[unstable(feature = "reentrant_lock", issue = "121440")]
+pub use self::reentrant_lock::{ReentrantLock, ReentrantLockGuard};
 
 pub mod mpsc;
 
@@ -192,5 +193,5 @@ mod mutex;
 pub(crate) mod once;
 mod once_lock;
 mod poison;
-mod remutex;
+mod reentrant_lock;
 mod rwlock;
diff --git a/library/std/src/sync/reentrant_lock.rs b/library/std/src/sync/reentrant_lock.rs
new file mode 100644
index 0000000000000..9a44998ebf644
--- /dev/null
+++ b/library/std/src/sync/reentrant_lock.rs
@@ -0,0 +1,320 @@
+#[cfg(all(test, not(target_os = "emscripten")))]
+mod tests;
+
+use crate::cell::UnsafeCell;
+use crate::fmt;
+use crate::ops::Deref;
+use crate::panic::{RefUnwindSafe, UnwindSafe};
+use crate::sync::atomic::{AtomicUsize, Ordering::Relaxed};
+use crate::sys::locks as sys;
+
+/// A re-entrant mutual exclusion lock
+///
+/// This lock will block *other* threads waiting for the lock to become
+/// available. The thread which has already locked the mutex can lock it
+/// multiple times without blocking, preventing a common source of deadlocks.
+///
+/// # Examples
+///
+/// Allow recursively calling a function needing synchronization from within
+/// a callback (this is how [`StdoutLock`](crate::io::StdoutLock) is currently
+/// implemented):
+///
+/// ```
+/// #![feature(reentrant_lock)]
+///
+/// use std::cell::RefCell;
+/// use std::sync::ReentrantLock;
+///
+/// pub struct Log {
+///     data: RefCell<String>,
+/// }
+///
+/// impl Log {
+///     pub fn append(&self, msg: &str) {
+///         self.data.borrow_mut().push_str(msg);
+///     }
+/// }
+///
+/// static LOG: ReentrantLock<Log> = ReentrantLock::new(Log { data: RefCell::new(String::new()) });
+///
+/// pub fn with_log<R>(f: impl FnOnce(&Log) -> R) -> R {
+///     let log = LOG.lock();
+///     f(&*log)
+/// }
+///
+/// with_log(|log| {
+///     log.append("Hello");
+///     with_log(|log| log.append(" there!"));
+/// });
+/// ```
+///
+// # Implementation details
+//
+// The 'owner' field tracks which thread has locked the mutex.
+//
+// We use current_thread_unique_ptr() as the thread identifier,
+// which is just the address of a thread local variable.
+//
+// If `owner` is set to the identifier of the current thread,
+// we assume the mutex is already locked and instead of locking it again,
+// we increment `lock_count`.
+//
+// When unlocking, we decrement `lock_count`, and only unlock the mutex when
+// it reaches zero.
+//
+// `lock_count` is protected by the mutex and only accessed by the thread that has
+// locked the mutex, so needs no synchronization.
+//
+// `owner` can be checked by other threads that want to see if they already
+// hold the lock, so needs to be atomic. If it compares equal, we're on the
+// same thread that holds the mutex and memory access can use relaxed ordering
+// since we're not dealing with multiple threads. If it's not equal,
+// synchronization is left to the mutex, making relaxed memory ordering for
+// the `owner` field fine in all cases.
+#[unstable(feature = "reentrant_lock", issue = "121440")]
+pub struct ReentrantLock<T: ?Sized> {
+    mutex: sys::Mutex,
+    owner: AtomicUsize,
+    lock_count: UnsafeCell<u32>,
+    data: T,
+}
+
+#[unstable(feature = "reentrant_lock", issue = "121440")]
+unsafe impl<T: Send + ?Sized> Send for ReentrantLock<T> {}
+#[unstable(feature = "reentrant_lock", issue = "121440")]
+unsafe impl<T: Send + ?Sized> Sync for ReentrantLock<T> {}
+
+// Because of the `UnsafeCell`, these traits are not implemented automatically
+#[unstable(feature = "reentrant_lock", issue = "121440")]
+impl<T: UnwindSafe + ?Sized> UnwindSafe for ReentrantLock<T> {}
+#[unstable(feature = "reentrant_lock", issue = "121440")]
+impl<T: RefUnwindSafe + ?Sized> RefUnwindSafe for ReentrantLock<T> {}
+
+/// An RAII implementation of a "scoped lock" of a re-entrant lock. When this
+/// structure is dropped (falls out of scope), the lock will be unlocked.
+///
+/// The data protected by the mutex can be accessed through this guard via its
+/// [`Deref`] implementation.
+///
+/// This structure is created by the [`lock`](ReentrantLock::lock) method on
+/// [`ReentrantLock`].
+///
+/// # Mutability
+///
+/// Unlike [`MutexGuard`](super::MutexGuard), `ReentrantLockGuard` does not
+/// implement [`DerefMut`](crate::ops::DerefMut), because implementation of
+/// the trait would violate Rust’s reference aliasing rules. Use interior
+/// mutability (usually [`RefCell`](crate::cell::RefCell)) in order to mutate
+/// the guarded data.
+#[must_use = "if unused the ReentrantLock will immediately unlock"]
+#[unstable(feature = "reentrant_lock", issue = "121440")]
+pub struct ReentrantLockGuard<'a, T: ?Sized + 'a> {
+    lock: &'a ReentrantLock<T>,
+}
+
+#[unstable(feature = "reentrant_lock", issue = "121440")]
+impl<T: ?Sized> !Send for ReentrantLockGuard<'_, T> {}
+
+#[unstable(feature = "reentrant_lock", issue = "121440")]
+impl<T> ReentrantLock<T> {
+    /// Creates a new re-entrant lock in an unlocked state ready for use.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// #![feature(reentrant_lock)]
+    /// use std::sync::ReentrantLock;
+    ///
+    /// let lock = ReentrantLock::new(0);
+    /// ```
+    pub const fn new(t: T) -> ReentrantLock<T> {
+        ReentrantLock {
+            mutex: sys::Mutex::new(),
+            owner: AtomicUsize::new(0),
+            lock_count: UnsafeCell::new(0),
+            data: t,
+        }
+    }
+
+    /// Consumes this lock, returning the underlying data.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// #![feature(reentrant_lock)]
+    ///
+    /// use std::sync::ReentrantLock;
+    ///
+    /// let lock = ReentrantLock::new(0);
+    /// assert_eq!(lock.into_inner(), 0);
+    /// ```
+    pub fn into_inner(self) -> T {
+        self.data
+    }
+}
+
+#[unstable(feature = "reentrant_lock", issue = "121440")]
+impl<T: ?Sized> ReentrantLock<T> {
+    /// Acquires the lock, blocking the current thread until it is able to do
+    /// so.
+    ///
+    /// This function will block the caller until it is available to acquire
+    /// the lock. Upon returning, the thread is the only thread with the lock
+    /// held. When the thread calling this method already holds the lock, the
+    /// call succeeds without blocking.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// #![feature(reentrant_lock)]
+    /// use std::cell::Cell;
+    /// use std::sync::{Arc, ReentrantLock};
+    /// use std::thread;
+    ///
+    /// let lock = Arc::new(ReentrantLock::new(Cell::new(0)));
+    /// let c_lock = Arc::clone(&lock);
+    ///
+    /// thread::spawn(move || {
+    ///     c_lock.lock().set(10);
+    /// }).join().expect("thread::spawn failed");
+    /// assert_eq!(lock.lock().get(), 10);
+    /// ```
+    pub fn lock(&self) -> ReentrantLockGuard<'_, T> {
+        let this_thread = current_thread_unique_ptr();
+        // Safety: We only touch lock_count when we own the lock.
+        unsafe {
+            if self.owner.load(Relaxed) == this_thread {
+                self.increment_lock_count().expect("lock count overflow in reentrant mutex");
+            } else {
+                self.mutex.lock();
+                self.owner.store(this_thread, Relaxed);
+                debug_assert_eq!(*self.lock_count.get(), 0);
+                *self.lock_count.get() = 1;
+            }
+        }
+        ReentrantLockGuard { lock: self }
+    }
+
+    /// Returns a mutable reference to the underlying data.
+    ///
+    /// Since this call borrows the `ReentrantLock` mutably, no actual locking
+    /// needs to take place -- the mutable borrow statically guarantees no locks
+    /// exist.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// #![feature(reentrant_lock)]
+    /// use std::sync::ReentrantLock;
+    ///
+    /// let mut lock = ReentrantLock::new(0);
+    /// *lock.get_mut() = 10;
+    /// assert_eq!(*lock.lock(), 10);
+    /// ```
+    pub fn get_mut(&mut self) -> &mut T {
+        &mut self.data
+    }
+
+    /// Attempts to acquire this lock.
+    ///
+    /// If the lock could not be acquired at this time, then `None` is returned.
+    /// Otherwise, an RAII guard is returned.
+    ///
+    /// This function does not block.
+    pub(crate) fn try_lock(&self) -> Option<ReentrantLockGuard<'_, T>> {
+        let this_thread = current_thread_unique_ptr();
+        // Safety: We only touch lock_count when we own the lock.
+        unsafe {
+            if self.owner.load(Relaxed) == this_thread {
+                self.increment_lock_count()?;
+                Some(ReentrantLockGuard { lock: self })
+            } else if self.mutex.try_lock() {
+                self.owner.store(this_thread, Relaxed);
+                debug_assert_eq!(*self.lock_count.get(), 0);
+                *self.lock_count.get() = 1;
+                Some(ReentrantLockGuard { lock: self })
+            } else {
+                None
+            }
+        }
+    }
+
+    unsafe fn increment_lock_count(&self) -> Option<()> {
+        *self.lock_count.get() = (*self.lock_count.get()).checked_add(1)?;
+        Some(())
+    }
+}
+
+#[unstable(feature = "reentrant_lock", issue = "121440")]
+impl<T: fmt::Debug + ?Sized> fmt::Debug for ReentrantLock<T> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        let mut d = f.debug_struct("ReentrantLock");
+        match self.try_lock() {
+            Some(v) => d.field("data", &&*v),
+            None => d.field("data", &format_args!("<locked>")),
+        };
+        d.finish_non_exhaustive()
+    }
+}
+
+#[unstable(feature = "reentrant_lock", issue = "121440")]
+impl<T: Default> Default for ReentrantLock<T> {
+    fn default() -> Self {
+        Self::new(T::default())
+    }
+}
+
+#[unstable(feature = "reentrant_lock", issue = "121440")]
+impl<T> From<T> for ReentrantLock<T> {
+    fn from(t: T) -> Self {
+        Self::new(t)
+    }
+}
+
+#[unstable(feature = "reentrant_lock", issue = "121440")]
+impl<T: ?Sized> Deref for ReentrantLockGuard<'_, T> {
+    type Target = T;
+
+    fn deref(&self) -> &T {
+        &self.lock.data
+    }
+}
+
+#[unstable(feature = "reentrant_lock", issue = "121440")]
+impl<T: fmt::Debug + ?Sized> fmt::Debug for ReentrantLockGuard<'_, T> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        (**self).fmt(f)
+    }
+}
+
+#[unstable(feature = "reentrant_lock", issue = "121440")]
+impl<T: fmt::Display + ?Sized> fmt::Display for ReentrantLockGuard<'_, T> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        (**self).fmt(f)
+    }
+}
+
+#[unstable(feature = "reentrant_lock", issue = "121440")]
+impl<T: ?Sized> Drop for ReentrantLockGuard<'_, T> {
+    #[inline]
+    fn drop(&mut self) {
+        // Safety: We own the lock.
+        unsafe {
+            *self.lock.lock_count.get() -= 1;
+            if *self.lock.lock_count.get() == 0 {
+                self.lock.owner.store(0, Relaxed);
+                self.lock.mutex.unlock();
+            }
+        }
+    }
+}
+
+/// Get an address that is unique per running thread.
+///
+/// This can be used as a non-null usize-sized ID.
+pub(crate) fn current_thread_unique_ptr() -> usize {
+    // Use a non-drop type to make sure it's still available during thread destruction.
+    thread_local! { static X: u8 = const { 0 } }
+    X.with(|x| <*const _>::addr(x))
+}
diff --git a/library/std/src/sync/remutex/tests.rs b/library/std/src/sync/reentrant_lock/tests.rs
similarity index 53%
rename from library/std/src/sync/remutex/tests.rs
rename to library/std/src/sync/reentrant_lock/tests.rs
index fc553081d4227..d4c1d440c6109 100644
--- a/library/std/src/sync/remutex/tests.rs
+++ b/library/std/src/sync/reentrant_lock/tests.rs
@@ -1,17 +1,17 @@
-use super::{ReentrantMutex, ReentrantMutexGuard};
+use super::{ReentrantLock, ReentrantLockGuard};
 use crate::cell::RefCell;
 use crate::sync::Arc;
 use crate::thread;
 
 #[test]
 fn smoke() {
-    let m = ReentrantMutex::new(());
+    let l = ReentrantLock::new(());
     {
-        let a = m.lock();
+        let a = l.lock();
         {
-            let b = m.lock();
+            let b = l.lock();
             {
-                let c = m.lock();
+                let c = l.lock();
                 assert_eq!(*c, ());
             }
             assert_eq!(*b, ());
@@ -22,15 +22,15 @@ fn smoke() {
 
 #[test]
 fn is_mutex() {
-    let m = Arc::new(ReentrantMutex::new(RefCell::new(0)));
-    let m2 = m.clone();
-    let lock = m.lock();
+    let l = Arc::new(ReentrantLock::new(RefCell::new(0)));
+    let l2 = l.clone();
+    let lock = l.lock();
     let child = thread::spawn(move || {
-        let lock = m2.lock();
+        let lock = l2.lock();
         assert_eq!(*lock.borrow(), 4950);
     });
     for i in 0..100 {
-        let lock = m.lock();
+        let lock = l.lock();
         *lock.borrow_mut() += i;
     }
     drop(lock);
@@ -39,20 +39,20 @@ fn is_mutex() {
 
 #[test]
 fn trylock_works() {
-    let m = Arc::new(ReentrantMutex::new(()));
-    let m2 = m.clone();
-    let _lock = m.try_lock();
-    let _lock2 = m.try_lock();
+    let l = Arc::new(ReentrantLock::new(()));
+    let l2 = l.clone();
+    let _lock = l.try_lock();
+    let _lock2 = l.try_lock();
     thread::spawn(move || {
-        let lock = m2.try_lock();
+        let lock = l2.try_lock();
         assert!(lock.is_none());
     })
     .join()
     .unwrap();
-    let _lock3 = m.try_lock();
+    let _lock3 = l.try_lock();
 }
 
-pub struct Answer<'a>(pub ReentrantMutexGuard<'a, RefCell<u32>>);
+pub struct Answer<'a>(pub ReentrantLockGuard<'a, RefCell<u32>>);
 impl Drop for Answer<'_> {
     fn drop(&mut self) {
         *self.0.borrow_mut() = 42;
diff --git a/library/std/src/sync/remutex.rs b/library/std/src/sync/remutex.rs
deleted file mode 100644
index 0ced48d10b7c6..0000000000000
--- a/library/std/src/sync/remutex.rs
+++ /dev/null
@@ -1,178 +0,0 @@
-#[cfg(all(test, not(target_os = "emscripten")))]
-mod tests;
-
-use crate::cell::UnsafeCell;
-use crate::ops::Deref;
-use crate::panic::{RefUnwindSafe, UnwindSafe};
-use crate::sync::atomic::{AtomicUsize, Ordering::Relaxed};
-use crate::sys::locks as sys;
-
-/// A reentrant mutual exclusion
-///
-/// This mutex will block *other* threads waiting for the lock to become
-/// available. The thread which has already locked the mutex can lock it
-/// multiple times without blocking, preventing a common source of deadlocks.
-///
-/// This is used by stdout().lock() and friends.
-///
-/// ## Implementation details
-///
-/// The 'owner' field tracks which thread has locked the mutex.
-///
-/// We use current_thread_unique_ptr() as the thread identifier,
-/// which is just the address of a thread local variable.
-///
-/// If `owner` is set to the identifier of the current thread,
-/// we assume the mutex is already locked and instead of locking it again,
-/// we increment `lock_count`.
-///
-/// When unlocking, we decrement `lock_count`, and only unlock the mutex when
-/// it reaches zero.
-///
-/// `lock_count` is protected by the mutex and only accessed by the thread that has
-/// locked the mutex, so needs no synchronization.
-///
-/// `owner` can be checked by other threads that want to see if they already
-/// hold the lock, so needs to be atomic. If it compares equal, we're on the
-/// same thread that holds the mutex and memory access can use relaxed ordering
-/// since we're not dealing with multiple threads. If it's not equal,
-/// synchronization is left to the mutex, making relaxed memory ordering for
-/// the `owner` field fine in all cases.
-pub struct ReentrantMutex<T> {
-    mutex: sys::Mutex,
-    owner: AtomicUsize,
-    lock_count: UnsafeCell<u32>,
-    data: T,
-}
-
-unsafe impl<T: Send> Send for ReentrantMutex<T> {}
-unsafe impl<T: Send> Sync for ReentrantMutex<T> {}
-
-impl<T> UnwindSafe for ReentrantMutex<T> {}
-impl<T> RefUnwindSafe for ReentrantMutex<T> {}
-
-/// An RAII implementation of a "scoped lock" of a mutex. When this structure is
-/// dropped (falls out of scope), the lock will be unlocked.
-///
-/// The data protected by the mutex can be accessed through this guard via its
-/// Deref implementation.
-///
-/// # Mutability
-///
-/// Unlike `MutexGuard`, `ReentrantMutexGuard` does not implement `DerefMut`,
-/// because implementation of the trait would violate Rust’s reference aliasing
-/// rules. Use interior mutability (usually `RefCell`) in order to mutate the
-/// guarded data.
-#[must_use = "if unused the ReentrantMutex will immediately unlock"]
-pub struct ReentrantMutexGuard<'a, T: 'a> {
-    lock: &'a ReentrantMutex<T>,
-}
-
-impl<T> !Send for ReentrantMutexGuard<'_, T> {}
-
-impl<T> ReentrantMutex<T> {
-    /// Creates a new reentrant mutex in an unlocked state.
-    pub const fn new(t: T) -> ReentrantMutex<T> {
-        ReentrantMutex {
-            mutex: sys::Mutex::new(),
-            owner: AtomicUsize::new(0),
-            lock_count: UnsafeCell::new(0),
-            data: t,
-        }
-    }
-
-    /// Acquires a mutex, blocking the current thread until it is able to do so.
-    ///
-    /// This function will block the caller until it is available to acquire the mutex.
-    /// Upon returning, the thread is the only thread with the mutex held. When the thread
-    /// calling this method already holds the lock, the call shall succeed without
-    /// blocking.
-    ///
-    /// # Errors
-    ///
-    /// If another user of this mutex panicked while holding the mutex, then
-    /// this call will return failure if the mutex would otherwise be
-    /// acquired.
-    pub fn lock(&self) -> ReentrantMutexGuard<'_, T> {
-        let this_thread = current_thread_unique_ptr();
-        // Safety: We only touch lock_count when we own the lock.
-        unsafe {
-            if self.owner.load(Relaxed) == this_thread {
-                self.increment_lock_count();
-            } else {
-                self.mutex.lock();
-                self.owner.store(this_thread, Relaxed);
-                debug_assert_eq!(*self.lock_count.get(), 0);
-                *self.lock_count.get() = 1;
-            }
-        }
-        ReentrantMutexGuard { lock: self }
-    }
-
-    /// Attempts to acquire this lock.
-    ///
-    /// If the lock could not be acquired at this time, then `Err` is returned.
-    /// Otherwise, an RAII guard is returned.
-    ///
-    /// This function does not block.
-    ///
-    /// # Errors
-    ///
-    /// If another user of this mutex panicked while holding the mutex, then
-    /// this call will return failure if the mutex would otherwise be
-    /// acquired.
-    pub fn try_lock(&self) -> Option<ReentrantMutexGuard<'_, T>> {
-        let this_thread = current_thread_unique_ptr();
-        // Safety: We only touch lock_count when we own the lock.
-        unsafe {
-            if self.owner.load(Relaxed) == this_thread {
-                self.increment_lock_count();
-                Some(ReentrantMutexGuard { lock: self })
-            } else if self.mutex.try_lock() {
-                self.owner.store(this_thread, Relaxed);
-                debug_assert_eq!(*self.lock_count.get(), 0);
-                *self.lock_count.get() = 1;
-                Some(ReentrantMutexGuard { lock: self })
-            } else {
-                None
-            }
-        }
-    }
-
-    unsafe fn increment_lock_count(&self) {
-        *self.lock_count.get() = (*self.lock_count.get())
-            .checked_add(1)
-            .expect("lock count overflow in reentrant mutex");
-    }
-}
-
-impl<T> Deref for ReentrantMutexGuard<'_, T> {
-    type Target = T;
-
-    fn deref(&self) -> &T {
-        &self.lock.data
-    }
-}
-
-impl<T> Drop for ReentrantMutexGuard<'_, T> {
-    #[inline]
-    fn drop(&mut self) {
-        // Safety: We own the lock.
-        unsafe {
-            *self.lock.lock_count.get() -= 1;
-            if *self.lock.lock_count.get() == 0 {
-                self.lock.owner.store(0, Relaxed);
-                self.lock.mutex.unlock();
-            }
-        }
-    }
-}
-
-/// Get an address that is unique per running thread.
-///
-/// This can be used as a non-null usize-sized ID.
-pub fn current_thread_unique_ptr() -> usize {
-    // Use a non-drop type to make sure it's still available during thread destruction.
-    thread_local! { static X: u8 = const { 0 } }
-    X.with(|x| <*const _>::addr(x))
-}

From 5df9593f1ad13eac4ca1da281332c8147937cd34 Mon Sep 17 00:00:00 2001
From: Guillaume Gomez <guillaume.gomez@huawei.com>
Date: Tue, 27 Feb 2024 17:39:32 +0100
Subject: [PATCH 2/8] Prevent inclusion of whitespace character after
 macro_rules ident

---
 src/librustdoc/html/highlight.rs | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/librustdoc/html/highlight.rs b/src/librustdoc/html/highlight.rs
index 1cdc792a819a8..aa5998876d9ab 100644
--- a/src/librustdoc/html/highlight.rs
+++ b/src/librustdoc/html/highlight.rs
@@ -136,6 +136,7 @@ fn can_merge(class1: Option<Class>, class2: Option<Class>, text: &str) -> bool {
     match (class1, class2) {
         (Some(c1), Some(c2)) => c1.is_equal_to(c2),
         (Some(Class::Ident(_)), None) | (None, Some(Class::Ident(_))) => true,
+        (Some(Class::Macro(_)), _) => false,
         (Some(_), None) | (None, Some(_)) => text.trim().is_empty(),
         (None, None) => true,
     }

From 951f2d9ae2c3252e8076aebd54a519be83fcbab2 Mon Sep 17 00:00:00 2001
From: Nicholas Nethercote <n.nethercote@gmail.com>
Date: Wed, 28 Feb 2024 15:49:48 +1100
Subject: [PATCH 3/8] Use `LitKind::Err` for floats with empty exponents.

This prevents a follow-up type error in a test, which seems fine.
---
 compiler/rustc_parse/src/lexer/mod.rs         |  6 ++++--
 .../clippy/tests/ui/crashes/ice-10912.rs      |  2 --
 .../clippy/tests/ui/crashes/ice-10912.stderr  | 11 +---------
 ...nicode-confusable-in-float-literal-expt.rs |  1 -
 ...de-confusable-in-float-literal-expt.stderr | 21 +------------------
 5 files changed, 6 insertions(+), 35 deletions(-)

diff --git a/compiler/rustc_parse/src/lexer/mod.rs b/compiler/rustc_parse/src/lexer/mod.rs
index dc9f5bad765fc..4523276970deb 100644
--- a/compiler/rustc_parse/src/lexer/mod.rs
+++ b/compiler/rustc_parse/src/lexer/mod.rs
@@ -501,9 +501,11 @@ impl<'sess, 'src> StringReader<'sess, 'src> {
                 (kind, self.symbol_from_to(start, end))
             }
             rustc_lexer::LiteralKind::Float { base, empty_exponent } => {
+                let mut kind = token::Float;
                 if empty_exponent {
                     let span = self.mk_sp(start, self.pos);
-                    self.dcx().emit_err(errors::EmptyExponentFloat { span });
+                    let guar = self.dcx().emit_err(errors::EmptyExponentFloat { span });
+                    kind = token::Err(guar);
                 }
                 let base = match base {
                     Base::Hexadecimal => Some("hexadecimal"),
@@ -515,7 +517,7 @@ impl<'sess, 'src> StringReader<'sess, 'src> {
                     let span = self.mk_sp(start, end);
                     self.dcx().emit_err(errors::FloatLiteralUnsupportedBase { span, base });
                 }
-                (token::Float, self.symbol_from_to(start, end))
+                (kind, self.symbol_from_to(start, end))
             }
         }
     }
diff --git a/src/tools/clippy/tests/ui/crashes/ice-10912.rs b/src/tools/clippy/tests/ui/crashes/ice-10912.rs
index 8dfce19422171..1d689e1d0082d 100644
--- a/src/tools/clippy/tests/ui/crashes/ice-10912.rs
+++ b/src/tools/clippy/tests/ui/crashes/ice-10912.rs
@@ -2,7 +2,5 @@
 //@no-rustfix
 fn f2() -> impl Sized { && 3.14159265358979323846E }
 //~^ ERROR: expected at least one digit in exponent
-//~| ERROR: long literal lacking separators
-//~| NOTE: `-D clippy::unreadable-literal` implied by `-D warnings`
 
 fn main() {}
diff --git a/src/tools/clippy/tests/ui/crashes/ice-10912.stderr b/src/tools/clippy/tests/ui/crashes/ice-10912.stderr
index cc80354c7c626..c697e54679f96 100644
--- a/src/tools/clippy/tests/ui/crashes/ice-10912.stderr
+++ b/src/tools/clippy/tests/ui/crashes/ice-10912.stderr
@@ -4,14 +4,5 @@ error: expected at least one digit in exponent
 LL | fn f2() -> impl Sized { && 3.14159265358979323846E }
    |                            ^^^^^^^^^^^^^^^^^^^^^^^
 
-error: long literal lacking separators
-  --> tests/ui/crashes/ice-10912.rs:3:28
-   |
-LL | fn f2() -> impl Sized { && 3.14159265358979323846E }
-   |                            ^^^^^^^^^^^^^^^^^^^^^^^ help: consider: `3.141_592_653_589_793_238_46`
-   |
-   = note: `-D clippy::unreadable-literal` implied by `-D warnings`
-   = help: to override `-D warnings` add `#[allow(clippy::unreadable_literal)]`
-
-error: aborting due to 2 previous errors
+error: aborting due to 1 previous error
 
diff --git a/tests/ui/did_you_mean/issue-49746-unicode-confusable-in-float-literal-expt.rs b/tests/ui/did_you_mean/issue-49746-unicode-confusable-in-float-literal-expt.rs
index 66d562d2eb519..5c2c3b8ec61d5 100644
--- a/tests/ui/did_you_mean/issue-49746-unicode-confusable-in-float-literal-expt.rs
+++ b/tests/ui/did_you_mean/issue-49746-unicode-confusable-in-float-literal-expt.rs
@@ -1,6 +1,5 @@
 const UNIVERSAL_GRAVITATIONAL_CONSTANT: f64 = 6.674e−11; // m³⋅kg⁻¹⋅s⁻²
 //~^ ERROR expected at least one digit in exponent
 //~| ERROR unknown start of token: \u{2212}
-//~| ERROR cannot subtract `{integer}` from `{float}`
 
 fn main() {}
diff --git a/tests/ui/did_you_mean/issue-49746-unicode-confusable-in-float-literal-expt.stderr b/tests/ui/did_you_mean/issue-49746-unicode-confusable-in-float-literal-expt.stderr
index 44bdbb93ff51c..4b3d429c7509a 100644
--- a/tests/ui/did_you_mean/issue-49746-unicode-confusable-in-float-literal-expt.stderr
+++ b/tests/ui/did_you_mean/issue-49746-unicode-confusable-in-float-literal-expt.stderr
@@ -15,24 +15,5 @@ help: Unicode character '−' (Minus Sign) looks like '-' (Minus/Hyphen), but it
 LL | const UNIVERSAL_GRAVITATIONAL_CONSTANT: f64 = 6.674e-11; // m³⋅kg⁻¹⋅s⁻²
    |                                                     ~
 
-error[E0277]: cannot subtract `{integer}` from `{float}`
-  --> $DIR/issue-49746-unicode-confusable-in-float-literal-expt.rs:1:53
-   |
-LL | const UNIVERSAL_GRAVITATIONAL_CONSTANT: f64 = 6.674e−11; // m³⋅kg⁻¹⋅s⁻²
-   |                                                     ^ no implementation for `{float} - {integer}`
-   |
-   = help: the trait `Sub<{integer}>` is not implemented for `{float}`
-   = help: the following other types implement trait `Sub<Rhs>`:
-             <isize as Sub>
-             <isize as Sub<&isize>>
-             <i8 as Sub>
-             <i8 as Sub<&i8>>
-             <i16 as Sub>
-             <i16 as Sub<&i16>>
-             <i32 as Sub>
-             <i32 as Sub<&i32>>
-           and 48 others
-
-error: aborting due to 3 previous errors
+error: aborting due to 2 previous errors
 
-For more information about this error, try `rustc --explain E0277`.

From 79766098a469c72a24464e8157f58b3c6272f3d2 Mon Sep 17 00:00:00 2001
From: Nicholas Nethercote <n.nethercote@gmail.com>
Date: Wed, 28 Feb 2024 16:29:41 +1100
Subject: [PATCH 4/8] Reformat `float-field.rs` test.

- Put every literal in its own braces, rather than just some of them,
  for maximal error recovery.
- Add a blank line between every case, for readability.
---
 tests/ui/parser/float-field.rs     |  69 +++++++----
 tests/ui/parser/float-field.stderr | 186 ++++++++++++++---------------
 2 files changed, 142 insertions(+), 113 deletions(-)

diff --git a/tests/ui/parser/float-field.rs b/tests/ui/parser/float-field.rs
index eaa7465dc4d06..e074b0567a3fb 100644
--- a/tests/ui/parser/float-field.rs
+++ b/tests/ui/parser/float-field.rs
@@ -3,60 +3,89 @@ struct S(u8, (u8, u8));
 fn main() {
     let s = S(0, (0, 0));
 
-    s.1e1; //~ ERROR no field `1e1` on type `S`
-    s.1.; //~ ERROR unexpected token: `;`
-    s.1.1;
-    s.1.1e1; //~ ERROR no field `1e1` on type `(u8, u8)`
+    { s.1e1; } //~ ERROR no field `1e1` on type `S`
+
+    { s.1.; } //~ ERROR unexpected token: `;`
+
+    { s.1.1; }
+
+    { s.1.1e1; } //~ ERROR no field `1e1` on type `(u8, u8)`
+
     { s.1e+; } //~ ERROR unexpected token: `1e+`
                //~| ERROR expected one of `.`, `;`, `?`, `}`, or an operator, found `1e+`
                //~| ERROR expected at least one digit in exponent
+
     { s.1e-; } //~ ERROR unexpected token: `1e-`
                //~| ERROR expected one of `.`, `;`, `?`, `}`, or an operator, found `1e-`
                //~| ERROR expected at least one digit in exponent
+
     { s.1e+1; } //~ ERROR unexpected token: `1e+1`
                 //~| ERROR expected one of `.`, `;`, `?`, `}`, or an operator, found `1e+1`
+
     { s.1e-1; } //~ ERROR unexpected token: `1e-1`
                 //~| ERROR expected one of `.`, `;`, `?`, `}`, or an operator, found `1e-1`
+
     { s.1.1e+1; } //~ ERROR unexpected token: `1.1e+1`
                   //~| ERROR expected one of `.`, `;`, `?`, `}`, or an operator, found `1.1e+1`
+
     { s.1.1e-1; } //~ ERROR unexpected token: `1.1e-1`
                   //~| ERROR expected one of `.`, `;`, `?`, `}`, or an operator, found `1.1e-1`
-    s.0x1e1;  //~ ERROR no field `0x1e1` on type `S`
-    s.0x1.; //~ ERROR no field `0x1` on type `S`
-            //~| ERROR hexadecimal float literal is not supported
-            //~| ERROR unexpected token: `;`
-    s.0x1.1; //~ ERROR no field `0x1` on type `S`
-             //~| ERROR hexadecimal float literal is not supported
-    s.0x1.1e1; //~ ERROR no field `0x1` on type `S`
-               //~| ERROR hexadecimal float literal is not supported
+
+    { s.0x1e1; } //~ ERROR no field `0x1e1` on type `S`
+
+    { s.0x1.; } //~ ERROR no field `0x1` on type `S`
+                //~| ERROR hexadecimal float literal is not supported
+                //~| ERROR unexpected token: `;`
+
+    { s.0x1.1; } //~ ERROR no field `0x1` on type `S`
+                 //~| ERROR hexadecimal float literal is not supported
+
+    { s.0x1.1e1; } //~ ERROR no field `0x1` on type `S`
+                   //~| ERROR hexadecimal float literal is not supported
+
     { s.0x1e+; } //~ ERROR expected expression, found `;`
+
     { s.0x1e-; } //~ ERROR expected expression, found `;`
-    s.0x1e+1; //~ ERROR no field `0x1e` on type `S`
-    s.0x1e-1; //~ ERROR no field `0x1e` on type `S`
+
+    { s.0x1e+1; } //~ ERROR no field `0x1e` on type `S`
+
+    { s.0x1e-1; } //~ ERROR no field `0x1e` on type `S`
+
     { s.0x1.1e+1; } //~ ERROR unexpected token: `0x1.1e+1`
                     //~| ERROR expected one of `.`, `;`, `?`, `}`, or an operator, found `0x1.1e+1`
                     //~| ERROR hexadecimal float literal is not supported
+
     { s.0x1.1e-1; } //~ ERROR unexpected token: `0x1.1e-1`
                     //~| ERROR expected one of `.`, `;`, `?`, `}`, or an operator, found `0x1.1e-1`
                     //~| ERROR hexadecimal float literal is not supported
-    s.1e1f32; //~ ERROR no field `1e1` on type `S`
-              //~| ERROR suffixes on a tuple index are invalid
-    s.1.f32; //~ ERROR no field `f32` on type `(u8, u8)`
-    s.1.1f32; //~ ERROR suffixes on a tuple index are invalid
-    s.1.1e1f32; //~ ERROR no field `1e1` on type `(u8, u8)`
-                //~| ERROR suffixes on a tuple index are invalid
+
+    { s.1e1f32; } //~ ERROR no field `1e1` on type `S`
+                  //~| ERROR suffixes on a tuple index are invalid
+
+    { s.1.f32; } //~ ERROR no field `f32` on type `(u8, u8)`
+
+    { s.1.1f32; } //~ ERROR suffixes on a tuple index are invalid
+
+    { s.1.1e1f32; } //~ ERROR no field `1e1` on type `(u8, u8)`
+                    //~| ERROR suffixes on a tuple index are invalid
+
     { s.1e+f32; } //~ ERROR unexpected token: `1e+f32`
                   //~| ERROR expected one of `.`, `;`, `?`, `}`, or an operator, found `1e+f32`
                   //~| ERROR expected at least one digit in exponent
+
     { s.1e-f32; } //~ ERROR unexpected token: `1e-f32`
                   //~| ERROR expected one of `.`, `;`, `?`, `}`, or an operator, found `1e-f32`
                   //~| ERROR expected at least one digit in exponent
+
     { s.1e+1f32; } //~ ERROR unexpected token: `1e+1f32`
                    //~| ERROR expected one of `.`, `;`, `?`, `}`, or an operator, found `1e+1f32`
+
     { s.1e-1f32; } //~ ERROR unexpected token: `1e-1f32`
                    //~| ERROR expected one of `.`, `;`, `?`, `}`, or an operator, found `1e-1f32`
+
     { s.1.1e+1f32; } //~ ERROR unexpected token: `1.1e+1f32`
                     //~| ERROR expected one of `.`, `;`, `?`, `}`, or an operator, found `1.1e+1f32`
+
     { s.1.1e-1f32; } //~ ERROR unexpected token: `1.1e-1f32`
                     //~| ERROR expected one of `.`, `;`, `?`, `}`, or an operator, found `1.1e-1f32`
 }
diff --git a/tests/ui/parser/float-field.stderr b/tests/ui/parser/float-field.stderr
index d67d270ef7b93..0606e321ef477 100644
--- a/tests/ui/parser/float-field.stderr
+++ b/tests/ui/parser/float-field.stderr
@@ -1,348 +1,348 @@
 error: expected at least one digit in exponent
-  --> $DIR/float-field.rs:10:9
+  --> $DIR/float-field.rs:14:9
    |
 LL |     { s.1e+; }
    |         ^^^
 
 error: expected at least one digit in exponent
-  --> $DIR/float-field.rs:13:9
+  --> $DIR/float-field.rs:18:9
    |
 LL |     { s.1e-; }
    |         ^^^
 
 error: hexadecimal float literal is not supported
-  --> $DIR/float-field.rs:25:7
+  --> $DIR/float-field.rs:36:9
    |
-LL |     s.0x1.;
-   |       ^^^^
+LL |     { s.0x1.; }
+   |         ^^^^
 
 error: hexadecimal float literal is not supported
-  --> $DIR/float-field.rs:28:7
+  --> $DIR/float-field.rs:40:9
    |
-LL |     s.0x1.1;
-   |       ^^^^^
+LL |     { s.0x1.1; }
+   |         ^^^^^
 
 error: hexadecimal float literal is not supported
-  --> $DIR/float-field.rs:30:7
+  --> $DIR/float-field.rs:43:9
    |
-LL |     s.0x1.1e1;
-   |       ^^^^^^^
+LL |     { s.0x1.1e1; }
+   |         ^^^^^^^
 
 error: hexadecimal float literal is not supported
-  --> $DIR/float-field.rs:36:9
+  --> $DIR/float-field.rs:54:9
    |
 LL |     { s.0x1.1e+1; }
    |         ^^^^^^^^
 
 error: hexadecimal float literal is not supported
-  --> $DIR/float-field.rs:39:9
+  --> $DIR/float-field.rs:58:9
    |
 LL |     { s.0x1.1e-1; }
    |         ^^^^^^^^
 
 error: expected at least one digit in exponent
-  --> $DIR/float-field.rs:48:9
+  --> $DIR/float-field.rs:72:9
    |
 LL |     { s.1e+f32; }
    |         ^^^^^^
 
 error: expected at least one digit in exponent
-  --> $DIR/float-field.rs:51:9
+  --> $DIR/float-field.rs:76:9
    |
 LL |     { s.1e-f32; }
    |         ^^^^^^
 
 error: unexpected token: `;`
-  --> $DIR/float-field.rs:7:9
+  --> $DIR/float-field.rs:8:11
    |
-LL |     s.1.;
-   |         ^
+LL |     { s.1.; }
+   |           ^
 
 error: unexpected token: `1e+`
-  --> $DIR/float-field.rs:10:9
+  --> $DIR/float-field.rs:14:9
    |
 LL |     { s.1e+; }
    |         ^^^
 
 error: expected one of `.`, `;`, `?`, `}`, or an operator, found `1e+`
-  --> $DIR/float-field.rs:10:9
+  --> $DIR/float-field.rs:14:9
    |
 LL |     { s.1e+; }
    |         ^^^ expected one of `.`, `;`, `?`, `}`, or an operator
 
 error: unexpected token: `1e-`
-  --> $DIR/float-field.rs:13:9
+  --> $DIR/float-field.rs:18:9
    |
 LL |     { s.1e-; }
    |         ^^^
 
 error: expected one of `.`, `;`, `?`, `}`, or an operator, found `1e-`
-  --> $DIR/float-field.rs:13:9
+  --> $DIR/float-field.rs:18:9
    |
 LL |     { s.1e-; }
    |         ^^^ expected one of `.`, `;`, `?`, `}`, or an operator
 
 error: unexpected token: `1e+1`
-  --> $DIR/float-field.rs:16:9
+  --> $DIR/float-field.rs:22:9
    |
 LL |     { s.1e+1; }
    |         ^^^^
 
 error: expected one of `.`, `;`, `?`, `}`, or an operator, found `1e+1`
-  --> $DIR/float-field.rs:16:9
+  --> $DIR/float-field.rs:22:9
    |
 LL |     { s.1e+1; }
    |         ^^^^ expected one of `.`, `;`, `?`, `}`, or an operator
 
 error: unexpected token: `1e-1`
-  --> $DIR/float-field.rs:18:9
+  --> $DIR/float-field.rs:25:9
    |
 LL |     { s.1e-1; }
    |         ^^^^
 
 error: expected one of `.`, `;`, `?`, `}`, or an operator, found `1e-1`
-  --> $DIR/float-field.rs:18:9
+  --> $DIR/float-field.rs:25:9
    |
 LL |     { s.1e-1; }
    |         ^^^^ expected one of `.`, `;`, `?`, `}`, or an operator
 
 error: unexpected token: `1.1e+1`
-  --> $DIR/float-field.rs:20:9
+  --> $DIR/float-field.rs:28:9
    |
 LL |     { s.1.1e+1; }
    |         ^^^^^^
 
 error: expected one of `.`, `;`, `?`, `}`, or an operator, found `1.1e+1`
-  --> $DIR/float-field.rs:20:9
+  --> $DIR/float-field.rs:28:9
    |
 LL |     { s.1.1e+1; }
    |         ^^^^^^ expected one of `.`, `;`, `?`, `}`, or an operator
 
 error: unexpected token: `1.1e-1`
-  --> $DIR/float-field.rs:22:9
+  --> $DIR/float-field.rs:31:9
    |
 LL |     { s.1.1e-1; }
    |         ^^^^^^
 
 error: expected one of `.`, `;`, `?`, `}`, or an operator, found `1.1e-1`
-  --> $DIR/float-field.rs:22:9
+  --> $DIR/float-field.rs:31:9
    |
 LL |     { s.1.1e-1; }
    |         ^^^^^^ expected one of `.`, `;`, `?`, `}`, or an operator
 
 error: unexpected token: `;`
-  --> $DIR/float-field.rs:25:11
+  --> $DIR/float-field.rs:36:13
    |
-LL |     s.0x1.;
-   |           ^
+LL |     { s.0x1.; }
+   |             ^
 
 error: expected expression, found `;`
-  --> $DIR/float-field.rs:32:14
+  --> $DIR/float-field.rs:46:14
    |
 LL |     { s.0x1e+; }
    |              ^ expected expression
 
 error: expected expression, found `;`
-  --> $DIR/float-field.rs:33:14
+  --> $DIR/float-field.rs:48:14
    |
 LL |     { s.0x1e-; }
    |              ^ expected expression
 
 error: unexpected token: `0x1.1e+1`
-  --> $DIR/float-field.rs:36:9
+  --> $DIR/float-field.rs:54:9
    |
 LL |     { s.0x1.1e+1; }
    |         ^^^^^^^^
 
 error: expected one of `.`, `;`, `?`, `}`, or an operator, found `0x1.1e+1`
-  --> $DIR/float-field.rs:36:9
+  --> $DIR/float-field.rs:54:9
    |
 LL |     { s.0x1.1e+1; }
    |         ^^^^^^^^ expected one of `.`, `;`, `?`, `}`, or an operator
 
 error: unexpected token: `0x1.1e-1`
-  --> $DIR/float-field.rs:39:9
+  --> $DIR/float-field.rs:58:9
    |
 LL |     { s.0x1.1e-1; }
    |         ^^^^^^^^
 
 error: expected one of `.`, `;`, `?`, `}`, or an operator, found `0x1.1e-1`
-  --> $DIR/float-field.rs:39:9
+  --> $DIR/float-field.rs:58:9
    |
 LL |     { s.0x1.1e-1; }
    |         ^^^^^^^^ expected one of `.`, `;`, `?`, `}`, or an operator
 
 error: suffixes on a tuple index are invalid
-  --> $DIR/float-field.rs:42:7
+  --> $DIR/float-field.rs:62:9
    |
-LL |     s.1e1f32;
-   |       ^^^^^^ invalid suffix `f32`
+LL |     { s.1e1f32; }
+   |         ^^^^^^ invalid suffix `f32`
 
 error: suffixes on a tuple index are invalid
-  --> $DIR/float-field.rs:45:7
+  --> $DIR/float-field.rs:67:9
    |
-LL |     s.1.1f32;
-   |       ^^^^^^ invalid suffix `f32`
+LL |     { s.1.1f32; }
+   |         ^^^^^^ invalid suffix `f32`
 
 error: suffixes on a tuple index are invalid
-  --> $DIR/float-field.rs:46:7
+  --> $DIR/float-field.rs:69:9
    |
-LL |     s.1.1e1f32;
-   |       ^^^^^^^^ invalid suffix `f32`
+LL |     { s.1.1e1f32; }
+   |         ^^^^^^^^ invalid suffix `f32`
 
 error: unexpected token: `1e+f32`
-  --> $DIR/float-field.rs:48:9
+  --> $DIR/float-field.rs:72:9
    |
 LL |     { s.1e+f32; }
    |         ^^^^^^
 
 error: expected one of `.`, `;`, `?`, `}`, or an operator, found `1e+f32`
-  --> $DIR/float-field.rs:48:9
+  --> $DIR/float-field.rs:72:9
    |
 LL |     { s.1e+f32; }
    |         ^^^^^^ expected one of `.`, `;`, `?`, `}`, or an operator
 
 error: unexpected token: `1e-f32`
-  --> $DIR/float-field.rs:51:9
+  --> $DIR/float-field.rs:76:9
    |
 LL |     { s.1e-f32; }
    |         ^^^^^^
 
 error: expected one of `.`, `;`, `?`, `}`, or an operator, found `1e-f32`
-  --> $DIR/float-field.rs:51:9
+  --> $DIR/float-field.rs:76:9
    |
 LL |     { s.1e-f32; }
    |         ^^^^^^ expected one of `.`, `;`, `?`, `}`, or an operator
 
 error: unexpected token: `1e+1f32`
-  --> $DIR/float-field.rs:54:9
+  --> $DIR/float-field.rs:80:9
    |
 LL |     { s.1e+1f32; }
    |         ^^^^^^^
 
 error: expected one of `.`, `;`, `?`, `}`, or an operator, found `1e+1f32`
-  --> $DIR/float-field.rs:54:9
+  --> $DIR/float-field.rs:80:9
    |
 LL |     { s.1e+1f32; }
    |         ^^^^^^^ expected one of `.`, `;`, `?`, `}`, or an operator
 
 error: unexpected token: `1e-1f32`
-  --> $DIR/float-field.rs:56:9
+  --> $DIR/float-field.rs:83:9
    |
 LL |     { s.1e-1f32; }
    |         ^^^^^^^
 
 error: expected one of `.`, `;`, `?`, `}`, or an operator, found `1e-1f32`
-  --> $DIR/float-field.rs:56:9
+  --> $DIR/float-field.rs:83:9
    |
 LL |     { s.1e-1f32; }
    |         ^^^^^^^ expected one of `.`, `;`, `?`, `}`, or an operator
 
 error: unexpected token: `1.1e+1f32`
-  --> $DIR/float-field.rs:58:9
+  --> $DIR/float-field.rs:86:9
    |
 LL |     { s.1.1e+1f32; }
    |         ^^^^^^^^^
 
 error: expected one of `.`, `;`, `?`, `}`, or an operator, found `1.1e+1f32`
-  --> $DIR/float-field.rs:58:9
+  --> $DIR/float-field.rs:86:9
    |
 LL |     { s.1.1e+1f32; }
    |         ^^^^^^^^^ expected one of `.`, `;`, `?`, `}`, or an operator
 
 error: unexpected token: `1.1e-1f32`
-  --> $DIR/float-field.rs:60:9
+  --> $DIR/float-field.rs:89:9
    |
 LL |     { s.1.1e-1f32; }
    |         ^^^^^^^^^
 
 error: expected one of `.`, `;`, `?`, `}`, or an operator, found `1.1e-1f32`
-  --> $DIR/float-field.rs:60:9
+  --> $DIR/float-field.rs:89:9
    |
 LL |     { s.1.1e-1f32; }
    |         ^^^^^^^^^ expected one of `.`, `;`, `?`, `}`, or an operator
 
 error[E0609]: no field `1e1` on type `S`
-  --> $DIR/float-field.rs:6:7
+  --> $DIR/float-field.rs:6:9
    |
-LL |     s.1e1;
-   |       ^^^ unknown field
+LL |     { s.1e1; }
+   |         ^^^ unknown field
    |
    = note: available fields are: `0`, `1`
 
 error[E0609]: no field `1e1` on type `(u8, u8)`
-  --> $DIR/float-field.rs:9:9
+  --> $DIR/float-field.rs:12:11
    |
-LL |     s.1.1e1;
-   |         ^^^ unknown field
+LL |     { s.1.1e1; }
+   |           ^^^ unknown field
 
 error[E0609]: no field `0x1e1` on type `S`
-  --> $DIR/float-field.rs:24:7
+  --> $DIR/float-field.rs:34:9
    |
-LL |     s.0x1e1;
-   |       ^^^^^ unknown field
+LL |     { s.0x1e1; }
+   |         ^^^^^ unknown field
    |
    = note: available fields are: `0`, `1`
 
 error[E0609]: no field `0x1` on type `S`
-  --> $DIR/float-field.rs:25:7
+  --> $DIR/float-field.rs:36:9
    |
-LL |     s.0x1.;
-   |       ^^^ unknown field
+LL |     { s.0x1.; }
+   |         ^^^ unknown field
    |
    = note: available fields are: `0`, `1`
 
 error[E0609]: no field `0x1` on type `S`
-  --> $DIR/float-field.rs:28:7
+  --> $DIR/float-field.rs:40:9
    |
-LL |     s.0x1.1;
-   |       ^^^ unknown field
+LL |     { s.0x1.1; }
+   |         ^^^ unknown field
    |
    = note: available fields are: `0`, `1`
 
 error[E0609]: no field `0x1` on type `S`
-  --> $DIR/float-field.rs:30:7
+  --> $DIR/float-field.rs:43:9
    |
-LL |     s.0x1.1e1;
-   |       ^^^ unknown field
+LL |     { s.0x1.1e1; }
+   |         ^^^ unknown field
    |
    = note: available fields are: `0`, `1`
 
 error[E0609]: no field `0x1e` on type `S`
-  --> $DIR/float-field.rs:34:7
+  --> $DIR/float-field.rs:50:9
    |
-LL |     s.0x1e+1;
-   |       ^^^^ unknown field
+LL |     { s.0x1e+1; }
+   |         ^^^^ unknown field
    |
    = note: available fields are: `0`, `1`
 
 error[E0609]: no field `0x1e` on type `S`
-  --> $DIR/float-field.rs:35:7
+  --> $DIR/float-field.rs:52:9
    |
-LL |     s.0x1e-1;
-   |       ^^^^ unknown field
+LL |     { s.0x1e-1; }
+   |         ^^^^ unknown field
    |
    = note: available fields are: `0`, `1`
 
 error[E0609]: no field `1e1` on type `S`
-  --> $DIR/float-field.rs:42:7
+  --> $DIR/float-field.rs:62:9
    |
-LL |     s.1e1f32;
-   |       ^^^^^^ unknown field
+LL |     { s.1e1f32; }
+   |         ^^^^^^ unknown field
    |
    = note: available fields are: `0`, `1`
 
 error[E0609]: no field `f32` on type `(u8, u8)`
-  --> $DIR/float-field.rs:44:9
+  --> $DIR/float-field.rs:65:11
    |
-LL |     s.1.f32;
-   |         ^^^ unknown field
+LL |     { s.1.f32; }
+   |           ^^^ unknown field
 
 error[E0609]: no field `1e1` on type `(u8, u8)`
-  --> $DIR/float-field.rs:46:7
+  --> $DIR/float-field.rs:69:9
    |
-LL |     s.1.1e1f32;
-   |       ^^^^^^^^ unknown field
+LL |     { s.1.1e1f32; }
+   |         ^^^^^^^^ unknown field
 
 error: aborting due to 55 previous errors
 

From 840c8d3243761ac7d3976239aeba6f866f9df1eb Mon Sep 17 00:00:00 2001
From: Nicholas Nethercote <n.nethercote@gmail.com>
Date: Wed, 28 Feb 2024 16:30:20 +1100
Subject: [PATCH 5/8] Use `LitKind::Err` for floats with unsupported bases.

This slightly changes error messages in `float-field.rs`, but nothing of
real importance.
---
 compiler/rustc_parse/src/lexer/mod.rs |   4 +-
 tests/ui/parser/float-field.rs        |  16 ++--
 tests/ui/parser/float-field.stderr    | 124 ++++++++++++++------------
 3 files changed, 77 insertions(+), 67 deletions(-)

diff --git a/compiler/rustc_parse/src/lexer/mod.rs b/compiler/rustc_parse/src/lexer/mod.rs
index 4523276970deb..15ba80be1e63e 100644
--- a/compiler/rustc_parse/src/lexer/mod.rs
+++ b/compiler/rustc_parse/src/lexer/mod.rs
@@ -515,7 +515,9 @@ impl<'sess, 'src> StringReader<'sess, 'src> {
                 };
                 if let Some(base) = base {
                     let span = self.mk_sp(start, end);
-                    self.dcx().emit_err(errors::FloatLiteralUnsupportedBase { span, base });
+                    let guar =
+                        self.dcx().emit_err(errors::FloatLiteralUnsupportedBase { span, base });
+                    kind = token::Err(guar)
                 }
                 (kind, self.symbol_from_to(start, end))
             }
diff --git a/tests/ui/parser/float-field.rs b/tests/ui/parser/float-field.rs
index e074b0567a3fb..59fefee26aa6f 100644
--- a/tests/ui/parser/float-field.rs
+++ b/tests/ui/parser/float-field.rs
@@ -33,15 +33,17 @@ fn main() {
 
     { s.0x1e1; } //~ ERROR no field `0x1e1` on type `S`
 
-    { s.0x1.; } //~ ERROR no field `0x1` on type `S`
-                //~| ERROR hexadecimal float literal is not supported
-                //~| ERROR unexpected token: `;`
+    { s.0x1.; } //~ ERROR hexadecimal float literal is not supported
+                //~| ERROR unexpected token: `0x1.`
+                //~| ERROR expected one of `.`, `;`, `?`, `}`, or an operator, found `0x1.`
 
-    { s.0x1.1; } //~ ERROR no field `0x1` on type `S`
-                 //~| ERROR hexadecimal float literal is not supported
+    { s.0x1.1; } //~ ERROR hexadecimal float literal is not supported
+                 //~| ERROR unexpected token: `0x1.1`
+                 //~| expected one of `.`, `;`, `?`, `}`, or an operator, found `0x1.1`
 
-    { s.0x1.1e1; } //~ ERROR no field `0x1` on type `S`
-                   //~| ERROR hexadecimal float literal is not supported
+    { s.0x1.1e1; } //~ ERROR hexadecimal float literal is not supported
+                   //~| ERROR unexpected token: `0x1.1e1`
+                   //~| expected one of `.`, `;`, `?`, `}`, or an operator, found `0x1.1e1`
 
     { s.0x1e+; } //~ ERROR expected expression, found `;`
 
diff --git a/tests/ui/parser/float-field.stderr b/tests/ui/parser/float-field.stderr
index 0606e321ef477..0cc1b0767dc74 100644
--- a/tests/ui/parser/float-field.stderr
+++ b/tests/ui/parser/float-field.stderr
@@ -23,31 +23,31 @@ LL |     { s.0x1.1; }
    |         ^^^^^
 
 error: hexadecimal float literal is not supported
-  --> $DIR/float-field.rs:43:9
+  --> $DIR/float-field.rs:44:9
    |
 LL |     { s.0x1.1e1; }
    |         ^^^^^^^
 
 error: hexadecimal float literal is not supported
-  --> $DIR/float-field.rs:54:9
+  --> $DIR/float-field.rs:56:9
    |
 LL |     { s.0x1.1e+1; }
    |         ^^^^^^^^
 
 error: hexadecimal float literal is not supported
-  --> $DIR/float-field.rs:58:9
+  --> $DIR/float-field.rs:60:9
    |
 LL |     { s.0x1.1e-1; }
    |         ^^^^^^^^
 
 error: expected at least one digit in exponent
-  --> $DIR/float-field.rs:72:9
+  --> $DIR/float-field.rs:74:9
    |
 LL |     { s.1e+f32; }
    |         ^^^^^^
 
 error: expected at least one digit in exponent
-  --> $DIR/float-field.rs:76:9
+  --> $DIR/float-field.rs:78:9
    |
 LL |     { s.1e-f32; }
    |         ^^^^^^
@@ -130,134 +130,164 @@ error: expected one of `.`, `;`, `?`, `}`, or an operator, found `1.1e-1`
 LL |     { s.1.1e-1; }
    |         ^^^^^^ expected one of `.`, `;`, `?`, `}`, or an operator
 
-error: unexpected token: `;`
-  --> $DIR/float-field.rs:36:13
+error: unexpected token: `0x1.`
+  --> $DIR/float-field.rs:36:9
+   |
+LL |     { s.0x1.; }
+   |         ^^^^
+
+error: expected one of `.`, `;`, `?`, `}`, or an operator, found `0x1.`
+  --> $DIR/float-field.rs:36:9
    |
 LL |     { s.0x1.; }
-   |             ^
+   |         ^^^^ expected one of `.`, `;`, `?`, `}`, or an operator
+
+error: unexpected token: `0x1.1`
+  --> $DIR/float-field.rs:40:9
+   |
+LL |     { s.0x1.1; }
+   |         ^^^^^
+
+error: expected one of `.`, `;`, `?`, `}`, or an operator, found `0x1.1`
+  --> $DIR/float-field.rs:40:9
+   |
+LL |     { s.0x1.1; }
+   |         ^^^^^ expected one of `.`, `;`, `?`, `}`, or an operator
+
+error: unexpected token: `0x1.1e1`
+  --> $DIR/float-field.rs:44:9
+   |
+LL |     { s.0x1.1e1; }
+   |         ^^^^^^^
+
+error: expected one of `.`, `;`, `?`, `}`, or an operator, found `0x1.1e1`
+  --> $DIR/float-field.rs:44:9
+   |
+LL |     { s.0x1.1e1; }
+   |         ^^^^^^^ expected one of `.`, `;`, `?`, `}`, or an operator
 
 error: expected expression, found `;`
-  --> $DIR/float-field.rs:46:14
+  --> $DIR/float-field.rs:48:14
    |
 LL |     { s.0x1e+; }
    |              ^ expected expression
 
 error: expected expression, found `;`
-  --> $DIR/float-field.rs:48:14
+  --> $DIR/float-field.rs:50:14
    |
 LL |     { s.0x1e-; }
    |              ^ expected expression
 
 error: unexpected token: `0x1.1e+1`
-  --> $DIR/float-field.rs:54:9
+  --> $DIR/float-field.rs:56:9
    |
 LL |     { s.0x1.1e+1; }
    |         ^^^^^^^^
 
 error: expected one of `.`, `;`, `?`, `}`, or an operator, found `0x1.1e+1`
-  --> $DIR/float-field.rs:54:9
+  --> $DIR/float-field.rs:56:9
    |
 LL |     { s.0x1.1e+1; }
    |         ^^^^^^^^ expected one of `.`, `;`, `?`, `}`, or an operator
 
 error: unexpected token: `0x1.1e-1`
-  --> $DIR/float-field.rs:58:9
+  --> $DIR/float-field.rs:60:9
    |
 LL |     { s.0x1.1e-1; }
    |         ^^^^^^^^
 
 error: expected one of `.`, `;`, `?`, `}`, or an operator, found `0x1.1e-1`
-  --> $DIR/float-field.rs:58:9
+  --> $DIR/float-field.rs:60:9
    |
 LL |     { s.0x1.1e-1; }
    |         ^^^^^^^^ expected one of `.`, `;`, `?`, `}`, or an operator
 
 error: suffixes on a tuple index are invalid
-  --> $DIR/float-field.rs:62:9
+  --> $DIR/float-field.rs:64:9
    |
 LL |     { s.1e1f32; }
    |         ^^^^^^ invalid suffix `f32`
 
 error: suffixes on a tuple index are invalid
-  --> $DIR/float-field.rs:67:9
+  --> $DIR/float-field.rs:69:9
    |
 LL |     { s.1.1f32; }
    |         ^^^^^^ invalid suffix `f32`
 
 error: suffixes on a tuple index are invalid
-  --> $DIR/float-field.rs:69:9
+  --> $DIR/float-field.rs:71:9
    |
 LL |     { s.1.1e1f32; }
    |         ^^^^^^^^ invalid suffix `f32`
 
 error: unexpected token: `1e+f32`
-  --> $DIR/float-field.rs:72:9
+  --> $DIR/float-field.rs:74:9
    |
 LL |     { s.1e+f32; }
    |         ^^^^^^
 
 error: expected one of `.`, `;`, `?`, `}`, or an operator, found `1e+f32`
-  --> $DIR/float-field.rs:72:9
+  --> $DIR/float-field.rs:74:9
    |
 LL |     { s.1e+f32; }
    |         ^^^^^^ expected one of `.`, `;`, `?`, `}`, or an operator
 
 error: unexpected token: `1e-f32`
-  --> $DIR/float-field.rs:76:9
+  --> $DIR/float-field.rs:78:9
    |
 LL |     { s.1e-f32; }
    |         ^^^^^^
 
 error: expected one of `.`, `;`, `?`, `}`, or an operator, found `1e-f32`
-  --> $DIR/float-field.rs:76:9
+  --> $DIR/float-field.rs:78:9
    |
 LL |     { s.1e-f32; }
    |         ^^^^^^ expected one of `.`, `;`, `?`, `}`, or an operator
 
 error: unexpected token: `1e+1f32`
-  --> $DIR/float-field.rs:80:9
+  --> $DIR/float-field.rs:82:9
    |
 LL |     { s.1e+1f32; }
    |         ^^^^^^^
 
 error: expected one of `.`, `;`, `?`, `}`, or an operator, found `1e+1f32`
-  --> $DIR/float-field.rs:80:9
+  --> $DIR/float-field.rs:82:9
    |
 LL |     { s.1e+1f32; }
    |         ^^^^^^^ expected one of `.`, `;`, `?`, `}`, or an operator
 
 error: unexpected token: `1e-1f32`
-  --> $DIR/float-field.rs:83:9
+  --> $DIR/float-field.rs:85:9
    |
 LL |     { s.1e-1f32; }
    |         ^^^^^^^
 
 error: expected one of `.`, `;`, `?`, `}`, or an operator, found `1e-1f32`
-  --> $DIR/float-field.rs:83:9
+  --> $DIR/float-field.rs:85:9
    |
 LL |     { s.1e-1f32; }
    |         ^^^^^^^ expected one of `.`, `;`, `?`, `}`, or an operator
 
 error: unexpected token: `1.1e+1f32`
-  --> $DIR/float-field.rs:86:9
+  --> $DIR/float-field.rs:88:9
    |
 LL |     { s.1.1e+1f32; }
    |         ^^^^^^^^^
 
 error: expected one of `.`, `;`, `?`, `}`, or an operator, found `1.1e+1f32`
-  --> $DIR/float-field.rs:86:9
+  --> $DIR/float-field.rs:88:9
    |
 LL |     { s.1.1e+1f32; }
    |         ^^^^^^^^^ expected one of `.`, `;`, `?`, `}`, or an operator
 
 error: unexpected token: `1.1e-1f32`
-  --> $DIR/float-field.rs:89:9
+  --> $DIR/float-field.rs:91:9
    |
 LL |     { s.1.1e-1f32; }
    |         ^^^^^^^^^
 
 error: expected one of `.`, `;`, `?`, `}`, or an operator, found `1.1e-1f32`
-  --> $DIR/float-field.rs:89:9
+  --> $DIR/float-field.rs:91:9
    |
 LL |     { s.1.1e-1f32; }
    |         ^^^^^^^^^ expected one of `.`, `;`, `?`, `}`, or an operator
@@ -284,32 +314,8 @@ LL |     { s.0x1e1; }
    |
    = note: available fields are: `0`, `1`
 
-error[E0609]: no field `0x1` on type `S`
-  --> $DIR/float-field.rs:36:9
-   |
-LL |     { s.0x1.; }
-   |         ^^^ unknown field
-   |
-   = note: available fields are: `0`, `1`
-
-error[E0609]: no field `0x1` on type `S`
-  --> $DIR/float-field.rs:40:9
-   |
-LL |     { s.0x1.1; }
-   |         ^^^ unknown field
-   |
-   = note: available fields are: `0`, `1`
-
-error[E0609]: no field `0x1` on type `S`
-  --> $DIR/float-field.rs:43:9
-   |
-LL |     { s.0x1.1e1; }
-   |         ^^^ unknown field
-   |
-   = note: available fields are: `0`, `1`
-
 error[E0609]: no field `0x1e` on type `S`
-  --> $DIR/float-field.rs:50:9
+  --> $DIR/float-field.rs:52:9
    |
 LL |     { s.0x1e+1; }
    |         ^^^^ unknown field
@@ -317,7 +323,7 @@ LL |     { s.0x1e+1; }
    = note: available fields are: `0`, `1`
 
 error[E0609]: no field `0x1e` on type `S`
-  --> $DIR/float-field.rs:52:9
+  --> $DIR/float-field.rs:54:9
    |
 LL |     { s.0x1e-1; }
    |         ^^^^ unknown field
@@ -325,7 +331,7 @@ LL |     { s.0x1e-1; }
    = note: available fields are: `0`, `1`
 
 error[E0609]: no field `1e1` on type `S`
-  --> $DIR/float-field.rs:62:9
+  --> $DIR/float-field.rs:64:9
    |
 LL |     { s.1e1f32; }
    |         ^^^^^^ unknown field
@@ -333,17 +339,17 @@ LL |     { s.1e1f32; }
    = note: available fields are: `0`, `1`
 
 error[E0609]: no field `f32` on type `(u8, u8)`
-  --> $DIR/float-field.rs:65:11
+  --> $DIR/float-field.rs:67:11
    |
 LL |     { s.1.f32; }
    |           ^^^ unknown field
 
 error[E0609]: no field `1e1` on type `(u8, u8)`
-  --> $DIR/float-field.rs:69:9
+  --> $DIR/float-field.rs:71:9
    |
 LL |     { s.1.1e1f32; }
    |         ^^^^^^^^ unknown field
 
-error: aborting due to 55 previous errors
+error: aborting due to 57 previous errors
 
 For more information about this error, try `rustc --explain E0609`.

From 12b991d9f8e969a3db6e41c53d0f3fe5fd69ad8d Mon Sep 17 00:00:00 2001
From: Nadrieril <nadrieril+git@gmail.com>
Date: Wed, 28 Feb 2024 13:26:36 +0100
Subject: [PATCH 6/8] Don't panic when encountering unexpected constructor

---
 compiler/rustc_pattern_analysis/src/constructor.rs | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/compiler/rustc_pattern_analysis/src/constructor.rs b/compiler/rustc_pattern_analysis/src/constructor.rs
index 483986969d167..b1f910b947a93 100644
--- a/compiler/rustc_pattern_analysis/src/constructor.rs
+++ b/compiler/rustc_pattern_analysis/src/constructor.rs
@@ -940,7 +940,7 @@ impl<Cx: TypeCx> ConstructorSet<Cx> {
             }
             ConstructorSet::Variants { variants, non_exhaustive } => {
                 let mut seen_set = index::IdxSet::new_empty(variants.len());
-                for idx in seen.iter().map(|c| c.as_variant().unwrap()) {
+                for idx in seen.iter().filter_map(|c| c.as_variant()) {
                     seen_set.insert(idx);
                 }
                 let mut skipped_a_hidden_variant = false;
@@ -969,7 +969,7 @@ impl<Cx: TypeCx> ConstructorSet<Cx> {
             ConstructorSet::Bool => {
                 let mut seen_false = false;
                 let mut seen_true = false;
-                for b in seen.iter().map(|ctor| ctor.as_bool().unwrap()) {
+                for b in seen.iter().filter_map(|ctor| ctor.as_bool()) {
                     if b {
                         seen_true = true;
                     } else {
@@ -989,7 +989,7 @@ impl<Cx: TypeCx> ConstructorSet<Cx> {
             }
             ConstructorSet::Integers { range_1, range_2 } => {
                 let seen_ranges: Vec<_> =
-                    seen.iter().map(|ctor| *ctor.as_int_range().unwrap()).collect();
+                    seen.iter().filter_map(|ctor| ctor.as_int_range()).copied().collect();
                 for (seen, splitted_range) in range_1.split(seen_ranges.iter().cloned()) {
                     match seen {
                         Presence::Unseen => missing.push(IntRange(splitted_range)),
@@ -1006,7 +1006,7 @@ impl<Cx: TypeCx> ConstructorSet<Cx> {
                 }
             }
             ConstructorSet::Slice { array_len, subtype_is_empty } => {
-                let seen_slices = seen.iter().map(|c| c.as_slice().unwrap());
+                let seen_slices = seen.iter().filter_map(|c| c.as_slice());
                 let base_slice = Slice::new(*array_len, VarLen(0, 0));
                 for (seen, splitted_slice) in base_slice.split(seen_slices) {
                     let ctor = Slice(splitted_slice);

From 632d26aeff1a943d4791ddad3025af61e0ff2256 Mon Sep 17 00:00:00 2001
From: Guillaume Gomez <guillaume.gomez@huawei.com>
Date: Tue, 27 Feb 2024 17:40:12 +0100
Subject: [PATCH 7/8] Add regression test for inclusion of whitespace
 characters in rustdoc highlighting

---
 .../html/highlight/fixtures/sample.html       |  2 +-
 tests/rustdoc/source-code-highlight.rs        | 29 +++++++++++++++++++
 2 files changed, 30 insertions(+), 1 deletion(-)
 create mode 100644 tests/rustdoc/source-code-highlight.rs

diff --git a/src/librustdoc/html/highlight/fixtures/sample.html b/src/librustdoc/html/highlight/fixtures/sample.html
index aa735e81597c7..773afd5c2cc30 100644
--- a/src/librustdoc/html/highlight/fixtures/sample.html
+++ b/src/librustdoc/html/highlight/fixtures/sample.html
@@ -32,7 +32,7 @@
     }
 }
 
-<span class="macro">macro_rules! </span>bar {
+<span class="macro">macro_rules!</span> bar {
     (<span class="macro-nonterminal">$foo</span>:tt) =&gt; {};
 }
 </code></pre>
diff --git a/tests/rustdoc/source-code-highlight.rs b/tests/rustdoc/source-code-highlight.rs
new file mode 100644
index 0000000000000..0a1be791ec2d8
--- /dev/null
+++ b/tests/rustdoc/source-code-highlight.rs
@@ -0,0 +1,29 @@
+// We need this option to be enabled for the `foo` macro declaration to ensure
+// that the link on the ident is not including whitespace characters.
+
+//@ compile-flags: -Zunstable-options --generate-link-to-definition
+#![crate_name = "foo"]
+
+// @has 'src/foo/source-code-highlight.rs.html'
+
+// @hasraw - '<a href="../../foo/macro.foo.html">foo</a>'
+#[macro_export]
+macro_rules! foo {
+    () => {}
+}
+
+// @hasraw - '<span class="macro">foo!</span>'
+foo! {}
+
+// @hasraw - '<a href="../../foo/fn.f.html">f</a>'
+#[rustfmt::skip]
+pub fn f () {}
+// @hasraw - '<a href="../../foo/struct.Bar.html">Bar</a>'
+// @hasraw - '<a href="../../foo/struct.Bar.html">Bar</a>'
+// @hasraw - '<a href="{{channel}}/std/primitive.u32.html">u32</a>'
+#[rustfmt::skip]
+pub struct Bar ( u32 );
+// @hasraw - '<a href="../../foo/enum.Foo.html">Foo</a>'
+pub enum Foo {
+    A,
+}

From 5cdbe83af82e0e48a05bc87ff41ef381e45391dc Mon Sep 17 00:00:00 2001
From: Michael Goulet <michael@errs.io>
Date: Tue, 27 Feb 2024 23:30:07 +0000
Subject: [PATCH 8/8] Opportunistically resolve regions when processing region
 outlives obligations

---
 .../src/infer/outlives/obligations.rs         | 10 +++++++++-
 .../impl-implied-bounds-compatibility.rs      |  2 +-
 .../impl-implied-bounds-compatibility.stderr  | 20 ++++---------------
 3 files changed, 14 insertions(+), 18 deletions(-)

diff --git a/compiler/rustc_infer/src/infer/outlives/obligations.rs b/compiler/rustc_infer/src/infer/outlives/obligations.rs
index c0a99e5cc4177..8dd3a1f40cc10 100644
--- a/compiler/rustc_infer/src/infer/outlives/obligations.rs
+++ b/compiler/rustc_infer/src/infer/outlives/obligations.rs
@@ -62,6 +62,7 @@
 use crate::infer::outlives::components::{push_outlives_components, Component};
 use crate::infer::outlives::env::RegionBoundPairs;
 use crate::infer::outlives::verify::VerifyBoundCx;
+use crate::infer::resolve::OpportunisticRegionResolver;
 use crate::infer::{
     self, GenericKind, InferCtxt, RegionObligation, SubregionOrigin, UndoLog, VerifyBound,
 };
@@ -69,7 +70,9 @@ use crate::traits::{ObligationCause, ObligationCauseCode};
 use rustc_data_structures::undo_log::UndoLogs;
 use rustc_middle::mir::ConstraintCategory;
 use rustc_middle::traits::query::NoSolution;
-use rustc_middle::ty::{self, GenericArgsRef, Region, Ty, TyCtxt, TypeVisitableExt};
+use rustc_middle::ty::{
+    self, GenericArgsRef, Region, Ty, TyCtxt, TypeFoldable as _, TypeVisitableExt,
+};
 use rustc_middle::ty::{GenericArgKind, PolyTypeOutlivesPredicate};
 use rustc_span::DUMMY_SP;
 use smallvec::smallvec;
@@ -176,6 +179,11 @@ impl<'tcx> InferCtxt<'tcx> {
                         .map_err(|NoSolution| (outlives, origin.clone()))?
                         .no_bound_vars()
                         .expect("started with no bound vars, should end with no bound vars");
+                // `TypeOutlives` is structural, so we should try to opportunistically resolve all
+                // region vids before processing regions, so we have a better chance to match clauses
+                // in our param-env.
+                let (sup_type, sub_region) =
+                    (sup_type, sub_region).fold_with(&mut OpportunisticRegionResolver::new(self));
 
                 debug!(?sup_type, ?sub_region, ?origin);
 
diff --git a/tests/ui/implied-bounds/impl-implied-bounds-compatibility.rs b/tests/ui/implied-bounds/impl-implied-bounds-compatibility.rs
index 7f3817b326adc..5e3d21eb26ad7 100644
--- a/tests/ui/implied-bounds/impl-implied-bounds-compatibility.rs
+++ b/tests/ui/implied-bounds/impl-implied-bounds-compatibility.rs
@@ -10,7 +10,7 @@ pub trait MessageListenersInterface {
 
 impl<'a> MessageListenersInterface for MessageListeners<'a> {
     fn listeners<'b>(&'b self) -> &'a MessageListeners<'b> {
-        //~^ ERROR cannot infer an appropriate lifetime for lifetime parameter 'b in generic type due to conflicting requirements
+        //~^ ERROR in type `&'a MessageListeners<'_>`, reference has a longer lifetime than the data it references
         self
     }
 }
diff --git a/tests/ui/implied-bounds/impl-implied-bounds-compatibility.stderr b/tests/ui/implied-bounds/impl-implied-bounds-compatibility.stderr
index 6a412eb5e4bee..e0cf15d0d1f33 100644
--- a/tests/ui/implied-bounds/impl-implied-bounds-compatibility.stderr
+++ b/tests/ui/implied-bounds/impl-implied-bounds-compatibility.stderr
@@ -1,27 +1,15 @@
-error[E0495]: cannot infer an appropriate lifetime for lifetime parameter 'b in generic type due to conflicting requirements
+error[E0491]: in type `&'a MessageListeners<'_>`, reference has a longer lifetime than the data it references
   --> $DIR/impl-implied-bounds-compatibility.rs:12:5
    |
 LL |     fn listeners<'b>(&'b self) -> &'a MessageListeners<'b> {
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-note: first, the lifetime cannot outlive the lifetime `'c` as defined here...
-  --> $DIR/impl-implied-bounds-compatibility.rs:12:5
-   |
-LL |     fn listeners<'b>(&'b self) -> &'a MessageListeners<'b> {
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-note: ...so that the method type is compatible with trait
-  --> $DIR/impl-implied-bounds-compatibility.rs:12:5
-   |
-LL |     fn listeners<'b>(&'b self) -> &'a MessageListeners<'b> {
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   = note: expected `fn(&'c MessageListeners<'_>) -> &'c MessageListeners<'c>`
-              found `fn(&MessageListeners<'_>) -> &'a MessageListeners<'_>`
-note: but, the lifetime must be valid for the lifetime `'a` as defined here...
+note: the pointer is valid for the lifetime `'a` as defined here
   --> $DIR/impl-implied-bounds-compatibility.rs:11:6
    |
 LL | impl<'a> MessageListenersInterface for MessageListeners<'a> {
    |      ^^
-note: ...so that the reference type `&'a MessageListeners<'_>` does not outlive the data it points at
+note: but the referenced data is only valid for the lifetime `'c` as defined here
   --> $DIR/impl-implied-bounds-compatibility.rs:12:5
    |
 LL |     fn listeners<'b>(&'b self) -> &'a MessageListeners<'b> {
@@ -29,4 +17,4 @@ LL |     fn listeners<'b>(&'b self) -> &'a MessageListeners<'b> {
 
 error: aborting due to 1 previous error
 
-For more information about this error, try `rustc --explain E0495`.
+For more information about this error, try `rustc --explain E0491`.