Auto merge of #68067 - JohnTitor:rollup-vsj5won, r=JohnTitor

Rollup of 10 pull requests

Successful merges:

 - #66254 (Make Layout::new const)
 - #67122 (Do not deduplicate diagnostics in UI tests)
 - #67358 (Add HashSet::get_or_insert_owned)
 - #67725 (Simplify into_key_slice_mut)
 - #67935 (Relax the Sized bounds on Pin::map_unchecked(_mut))
 - #67967 (Delay bug to prevent ICE in MIR borrowck)
 - #67975 (Export public scalar statics in wasm)
 - #68006 (Recognise riscv64 in compiletest)
 - #68040 (Cleanup)
 - #68054 (doc: add Null-unchecked version section to mut pointer as_mut method)

Failed merges:

 - #67258 (Introduce `X..`, `..X`, and `..=X` range patterns)

r? @ghost

1 files changed, 14 insertions, 0 deletions

diff --git a/src/libcore/ptr/mut_ptr.rs b/src/libcore/ptr/mut_ptr.rs
index b3bb2f179b1..4bc0a3e9faa 100644
--- a/src/libcore/ptr/mut_ptr.rs
+++ b/src/libcore/ptr/mut_ptr.rs
@@ -250,6 +250,20 @@ impl<T: ?Sized> *mut T {
     /// *first_value = 4;
     /// println!("{:?}", s); // It'll print: "[4, 2, 3]".
     /// ```
+    ///
+    /// # Null-unchecked version
+    ///
+    /// If you are sure the pointer can never be null and are looking for some kind of
+    /// `as_mut_unchecked` that returns the `&mut T` instead of `Option<&mut T>`, know that
+    /// you can dereference the pointer directly.
+    ///
+    /// ```
+    /// let mut s = [1, 2, 3];
+    /// let ptr: *mut u32 = s.as_mut_ptr();
+    /// let first_value = unsafe { &mut *ptr };
+    /// *first_value = 4;
+    /// println!("{:?}", s); // It'll print: "[4, 2, 3]".
+    /// ```
     #[stable(feature = "ptr_as_ref", since = "1.9.0")]
     #[inline]
     pub unsafe fn as_mut<'a>(self) -> Option<&'a mut T> {