dnrops
/
rust
mirror of https://github.com/rust-lang/rust.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Rollup merge of #131261 - clarfonthey:unsafe-cell-from-mut, r=m-ou-se 

Stabilize `UnsafeCell::from_mut`

Closes #111645.
FCP: https://github.com/rust-lang/rust/issues/111645#issuecomment-2393893003

Note that because `const_mut_refs` and `const_refs_to_cell` was stabilized, it's okay to const-stabilize this method as well.
This commit is contained in:
Matthias Krüger 2024-11-05 23:43:55 +01:00 committed by GitHub
parent bc5cf994db 6828a1edc6
commit efa5af96a1
No known key found for this signature in database
GPG Key ID: B5690EEEBB952194
1 changed files with 3 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
library/core/src/cell.rs
View File

@ -2122,7 +2122,6 @@ impl<T: ?Sized> UnsafeCell<T> {
/// # Examples
///
/// ```
/// # #![feature(unsafe_cell_from_mut)]
/// use std::cell::UnsafeCell;
///
/// let mut val = 42;
@ -2132,7 +2131,9 @@ impl<T: ?Sized> UnsafeCell<T> {
/// assert_eq!(*uc.get_mut(), 41);
/// ```
#[inline(always)]
#[unstable(feature = "unsafe_cell_from_mut", issue = "111645")]
#[stable(feature = "unsafe_cell_from_mut", since = "CURRENT_RUSTC_VERSION")]
#[rustc_const_stable(feature = "unsafe_cell_from_mut", since = "CURRENT_RUSTC_VERSION")]
#[cfg_attr(bootstrap, rustc_allow_const_fn_unstable(const_mut_refs))]
pub const fn from_mut(value: &mut T) -> &mut UnsafeCell<T> {
// SAFETY: `UnsafeCell<T>` has the same memory layout as `T` due to #[repr(transparent)].
unsafe { &mut *(value as *mut T as *mut UnsafeCell<T>) }