Auto merge of #98335 - JohnTitor:rollup-j2zudxv, r=JohnTitor

Rollup of 11 pull requests

Successful merges:

 - #94033 (Improve docs for `is_running` to explain use case)
 - #97269 (adjust transmute const stabilization version)
 - #97805 (Add proper tracing spans to rustc_trait_selection::traits::error_reporting)
 - #98022 (Fix erroneous span for borrowck error)
 - #98124 (Improve loading of crates.js and sidebar-items.js)
 - #98278 (Some token stream cleanups)
 - #98306 (`try_fold_unevaluated` for infallible folders)
 - #98313 (Remove lies in comments.)
 - #98323 (:arrow_up: rust-analyzer)
 - #98329 (Avoid an ICE and instead let the compiler report a useful error)
 - #98330 (update ioslice docs to use shared slices)

Failed merges:

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

6 files changed, 22 insertions, 21 deletions

diff --git a/library/std/src/io/mod.rs b/library/std/src/io/mod.rs
index cad1fab7b8f..f4f2e3f2434 100644
--- a/library/std/src/io/mod.rs
+++ b/library/std/src/io/mod.rs
@@ -1240,8 +1240,8 @@ impl<'a> IoSlice<'a> {
     /// use std::io::IoSlice;
     /// use std::ops::Deref;
     ///
-    /// let mut data = [1; 8];
-    /// let mut buf = IoSlice::new(&mut data);
+    /// let data = [1; 8];
+    /// let mut buf = IoSlice::new(&data);
     ///
     /// // Mark 3 bytes as read.
     /// buf.advance(3);
@@ -1435,10 +1435,10 @@ pub trait Write {
     /// use std::fs::File;
     ///
     /// fn main() -> std::io::Result<()> {
-    ///     let mut data1 = [1; 8];
-    ///     let mut data2 = [15; 8];
-    ///     let io_slice1 = IoSlice::new(&mut data1);
-    ///     let io_slice2 = IoSlice::new(&mut data2);
+    ///     let data1 = [1; 8];
+    ///     let data2 = [15; 8];
+    ///     let io_slice1 = IoSlice::new(&data1);
+    ///     let io_slice2 = IoSlice::new(&data2);
     ///
     ///     let mut buffer = File::create("foo.txt")?;
     ///
diff --git a/library/std/src/os/unix/net/ancillary.rs b/library/std/src/os/unix/net/ancillary.rs
index ecee123a9b6..7cc901a7944 100644
--- a/library/std/src/os/unix/net/ancillary.rs
+++ b/library/std/src/os/unix/net/ancillary.rs
@@ -583,8 +583,8 @@ impl<'a> SocketAncillary<'a> {
     ///     let mut ancillary = SocketAncillary::new(&mut ancillary_buffer[..]);
     ///     ancillary.add_fds(&[sock.as_raw_fd()][..]);
     ///
-    ///     let mut buf = [1; 8];
-    ///     let mut bufs = &mut [IoSlice::new(&mut buf[..])][..];
+    ///     let buf = [1; 8];
+    ///     let mut bufs = &mut [IoSlice::new(&buf[..])][..];
     ///     sock.send_vectored_with_ancillary(bufs, &mut ancillary)?;
     ///     Ok(())
     /// }
diff --git a/library/std/src/sys_common/mutex.rs b/library/std/src/sys_common/mutex.rs
index 81eefa1133f..48479f5bdb3 100644
--- a/library/std/src/sys_common/mutex.rs
+++ b/library/std/src/sys_common/mutex.rs
@@ -46,13 +46,12 @@ impl Drop for StaticMutexGuard {
 
 /// An OS-based mutual exclusion lock.
 ///
-/// This mutex does *not* have a const constructor, cleans up its resources in
-/// its `Drop` implementation, may safely be moved (when not borrowed), and
-/// does not cause UB when used reentrantly.
+/// This mutex cleans up its resources in its `Drop` implementation, may safely
+/// be moved (when not borrowed), and does not cause UB when used reentrantly.
 ///
 /// This mutex does not implement poisoning.
 ///
-/// This is either a wrapper around `Box<imp::Mutex>` or `imp::Mutex`,
+/// This is either a wrapper around `LazyBox<imp::Mutex>` or `imp::Mutex`,
 /// depending on the platform. It is boxed on platforms where `imp::Mutex` may
 /// not be moved.
 pub struct MovableMutex(imp::MovableMutex);
diff --git a/library/std/src/sys_common/rwlock.rs b/library/std/src/sys_common/rwlock.rs
index 265cebfdc3e..ba56f3a8f1b 100644
--- a/library/std/src/sys_common/rwlock.rs
+++ b/library/std/src/sys_common/rwlock.rs
@@ -62,12 +62,12 @@ impl Drop for StaticRwLockWriteGuard {
 
 /// An OS-based reader-writer lock.
 ///
-/// This rwlock does *not* have a const constructor, cleans up its resources in
-/// its `Drop` implementation and may safely be moved (when not borrowed).
+/// This rwlock cleans up its resources in its `Drop` implementation and may
+/// safely be moved (when not borrowed).
 ///
 /// This rwlock does not implement poisoning.
 ///
-/// This is either a wrapper around `Box<imp::RwLock>` or `imp::RwLock`,
+/// This is either a wrapper around `LazyBox<imp::RwLock>` or `imp::RwLock`,
 /// depending on the platform. It is boxed on platforms where `imp::RwLock` may
 /// not be moved.
 pub struct MovableRwLock(imp::MovableRwLock);
diff --git a/library/std/src/thread/mod.rs b/library/std/src/thread/mod.rs
index f7af66ae5b5..0a6a7cfe976 100644
--- a/library/std/src/thread/mod.rs
+++ b/library/std/src/thread/mod.rs
@@ -1487,13 +1487,14 @@ impl<T> JoinHandle<T> {
 
     /// Checks if the associated thread has finished running its main function.
     ///
+    /// `is_finished` supports implementing a non-blocking join operation, by checking
+    /// `is_finished`, and calling `join` if it returns `true`. This function does not block. To
+    /// block while waiting on the thread to finish, use [`join`][Self::join].
+    ///
     /// This might return `true` for a brief moment after the thread's main
     /// function has returned, but before the thread itself has stopped running.
     /// However, once this returns `true`, [`join`][Self::join] can be expected
     /// to return quickly, without blocking for any significant amount of time.
-    ///
-    /// This function does not block. To block while waiting on the thread to finish,
-    /// use [`join`][Self::join].
     #[stable(feature = "thread_is_running", since = "1.61.0")]
     pub fn is_finished(&self) -> bool {
         Arc::strong_count(&self.0.packet) == 1
diff --git a/library/std/src/thread/scoped.rs b/library/std/src/thread/scoped.rs
index 4fd076e4a2d..a387a09dc8b 100644
--- a/library/std/src/thread/scoped.rs
+++ b/library/std/src/thread/scoped.rs
@@ -308,13 +308,14 @@ impl<'scope, T> ScopedJoinHandle<'scope, T> {
 
     /// Checks if the associated thread has finished running its main function.
     ///
+    /// `is_finished` supports implementing a non-blocking join operation, by checking
+    /// `is_finished`, and calling `join` if it returns `false`. This function does not block. To
+    /// block while waiting on the thread to finish, use [`join`][Self::join].
+    ///
     /// This might return `true` for a brief moment after the thread's main
     /// function has returned, but before the thread itself has stopped running.
     /// However, once this returns `true`, [`join`][Self::join] can be expected
     /// to return quickly, without blocking for any significant amount of time.
-    ///
-    /// This function does not block. To block while waiting on the thread to finish,
-    /// use [`join`][Self::join].
     #[stable(feature = "scoped_threads", since = "1.63.0")]
     pub fn is_finished(&self) -> bool {
         Arc::strong_count(&self.0.packet) == 1