mathieu/granite-rust
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

relax a memory order in once_box

Browse source
This commit is contained in:
Slanterns 2024-10-16 00:22:05 +08:00
parent f79fae3069
commit 937d13b8ef
No known key found for this signature in database
GPG key ID: 1AA37EE7FAAE433A
1 changed files with 2 additions and 2 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

4
library/std/src/sys/sync/once_box.rs
View file

@ -8,7 +8,7 @@
use crate::mem::replace;
use crate::ptr::null_mut;
use crate::sync::atomic::AtomicPtr;
use crate::sync::atomic::Ordering::{AcqRel, Acquire, Relaxed};
use crate::sync::atomic::Ordering::{Acquire, Relaxed, Release};
pub(crate) struct OnceBox<T> {
ptr: AtomicPtr<T>,
@ -60,7 +60,7 @@ impl<T> OnceBox<T> {
#[cold]
fn initialize(&self, f: impl FnOnce() -> Box<T>) -> &T {
let new_ptr = Box::into_raw(f());
match self.ptr.compare_exchange(null_mut(), new_ptr, AcqRel, Acquire) {
match self.ptr.compare_exchange(null_mut(), new_ptr, Release, Acquire) {
Ok(_) => unsafe { &*new_ptr },
Err(ptr) => {
// Lost the race to another thread.