OpenE2K/rust
2
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

RwLock guards are Sync if T is

Browse Source 
Currently, the compiler requires `T` to also be `Send`.  There is no reason for
that.  `&Rw{Read,Write}LockGuard` only provides a shared referenced to `T`, sending
that across threads is safe if `T` is `Sync`.
This commit is contained in:
Ralf Jung 2017-11-01 13:39:44 +01:00
parent 2f581cf9d6
commit 71534c45cc
1 changed files with 8 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

11
src/libstd/sync/rwlock.rs
View File

@ -10,7 +10,6 @@
use cell::UnsafeCell;
use fmt;
use marker;
use mem;
use ops::{Deref, DerefMut};
use ptr;
@ -102,7 +101,10 @@ pub struct RwLockReadGuard<'a, T: ?Sized + 'a> {
}
#[stable(feature = "rust1", since = "1.0.0")]
impl<'a, T: ?Sized> !marker::Send for RwLockReadGuard<'a, T> {}
impl<'a, T: ?Sized> !Send for RwLockReadGuard<'a, T> {}
#[stable(feature = "rwlock_guard_sync", since = "1.23.0")]
unsafe impl<'a, T: ?Sized + Sync> Sync for RwLockReadGuard<'a, T> {}
/// RAII structure used to release the exclusive write access of a lock when
/// dropped.
@ -121,7 +123,10 @@ pub struct RwLockWriteGuard<'a, T: ?Sized + 'a> {
}
#[stable(feature = "rust1", since = "1.0.0")]
impl<'a, T: ?Sized> !marker::Send for RwLockWriteGuard<'a, T> {}
impl<'a, T: ?Sized> !Send for RwLockWriteGuard<'a, T> {}
#[stable(feature = "rwlock_guard_sync", since = "1.23.0")]
unsafe impl<'a, T: ?Sized + Sync> Sync for RwLockWriteGuard<'a, T> {}
impl<T> RwLock<T> {
/// Creates a new instance of an `RwLock<T>` which is unlocked.