diff options
| -rw-r--r-- | library/std/src/sync/rwlock.rs | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/library/std/src/sync/rwlock.rs b/library/std/src/sync/rwlock.rs index 02d221fe6c6..51e9c73d41a 100644 --- a/library/std/src/sync/rwlock.rs +++ b/library/std/src/sync/rwlock.rs @@ -102,6 +102,10 @@ unsafe impl<T: ?Sized + Send + Sync> Sync for RwLock<T> {} #[stable(feature = "rust1", since = "1.0.0")] #[clippy::has_significant_drop] pub struct RwLockReadGuard<'a, T: ?Sized + 'a> { + // NB: we use a pointer instead of `&'a T` to avoid `noalias` violations, because a + // `Ref` argument doesn't hold immutability for its whole scope, only until it drops. + // `NonNull` is also covariant over `T`, just like we would have with `&T`. `NonNull` + // is preferable over `const* T` to allow for niche optimization. data: NonNull<T>, inner_lock: &'a sys::MovableRwLock, } |