Auto merge of #50003 - kennytm:rollup, r=kennytm

Rollup of 8 pull requests

Successful merges:

 - #49555 (Inline most of the code paths for conversions with boxed slices)
 - #49606 (Prevent broken pipes causing ICEs)
 - #49646 (Use box syntax instead of Box::new in Mutex::remutex on Windows)
 - #49647 (Remove `underscore_lifetimes` and `match_default_bindings` from active feature list)
 - #49931 (Fix incorrect span in `&mut` suggestion)
 - #49959 (rustbuild: allow building tools with debuginfo)
 - #49965 (Remove warning about f64->f32 cast being potential UB)
 - #49994 (Remove unnecessary indentation in rustdoc book codeblock.)

Failed merges:

1 files changed, 1 insertions, 0 deletions

diff --git a/src/liballoc/string.rs b/src/liballoc/string.rs
index 0924ca24791..11fb82c09d3 100644
--- a/src/liballoc/string.rs
+++ b/src/liballoc/string.rs
@@ -1586,6 +1586,7 @@ impl String {
     /// let b = s.into_boxed_str();
     /// ```
     #[stable(feature = "box_str", since = "1.4.0")]
+    #[inline]
     pub fn into_boxed_str(self) -> Box<str> {
         let slice = self.vec.into_boxed_slice();
         unsafe { from_boxed_utf8_unchecked(slice) }