pub unsafe auto trait Send { }
Expand description
Types that can be transferred across thread boundaries.
This trait is automatically implemented when the compiler determines it’s appropriate.
An example of a non-Send
type is the reference-counting pointer
rc::Rc
. If two threads attempt to clone Rc
s that point to the same
reference-counted value, they might try to update the reference count at the
same time, which is undefined behavior because Rc
doesn’t use atomic
operations. Its cousin sync::Arc
does use atomic operations (incurring
some overhead) and thus is Send
.
See the Nomicon for more details.
Implementors
impl !Send for Args
impl !Send for ArgsOs
impl Send for Waker
impl Send for HandleOrInvalid
impl Send for HandleOrNull
impl Send for OwnedHandle
impl Send for std::sync::once::Once
impl<'_> Send for alloc::string::Drain<'_>
impl<'_> Send for BorrowedHandle<'_>
impl<'_, K, V> Send for IterMut<'_, K, V> where
K: Send,
V: Send,
impl<'_, K, V> Send for IterMut<'_, K, V> where
K: Send,
V: Send,
impl<'_, K, V, S, A> Send for OccupiedEntry<'_, K, V, S, A> where
K: Send,
V: Send,
S: Send,
A: Send + Allocator + Clone,
impl<'_, K, V, S, A> Send for OccupiedEntry<'_, K, V, S, A> where
K: Send,
V: Send,
S: Send,
A: Send + Allocator + Clone,
impl<'_, K, V, S, A> Send for RawOccupiedEntryMut<'_, K, V, S, A> where
K: Send,
V: Send,
A: Send + Allocator + Clone,
impl<'_, K, V, S, A> Send for RawOccupiedEntryMut<'_, K, V, S, A> where
K: Send,
V: Send,
S: Send,
A: Send + Allocator + Clone,
impl<'_, T> !Send for MutexGuard<'_, T> where
T: ?Sized,
impl<'_, T> !Send for RwLockReadGuard<'_, T> where
T: ?Sized,
impl<'_, T> !Send for RwLockWriteGuard<'_, T> where
T: ?Sized,
impl<'_, T> Send for &T where
T: Sync + ?Sized,
impl<'_, T> Send for &mut T where
T: Send + ?Sized,
impl<'_, T> Send for wasmtime_environ::__core::slice::Iter<'_, T> where
T: Sync,
impl<'_, T> Send for wasmtime_environ::__core::slice::IterMut<'_, T> where
T: Send,
impl<'_, T> Send for Cursor<'_, T> where
T: Sync,
impl<'_, T> Send for CursorMut<'_, T> where
T: Send,
impl<'_, T> Send for alloc::collections::linked_list::Iter<'_, T> where
T: Sync,
impl<'_, T> Send for alloc::collections::linked_list::IterMut<'_, T> where
T: Send,
impl<'_, T> Send for alloc::collections::vec_deque::iter_mut::IterMut<'_, T> where
T: Send,
impl<'_, T, A> Send for alloc::collections::vec_deque::drain::Drain<'_, T, A> where
T: Send,
A: Allocator + Send,
impl<'_, T, A> Send for alloc::vec::drain::Drain<'_, T, A> where
T: Send,
A: Send + Allocator,
impl<'_, T, A> Send for RawDrain<'_, T, A> where
A: Allocator + Copy + Send,
T: Send,
impl<'a> Send for IoSlice<'a>
impl<'a> Send for IoSliceMut<'a>
impl<'a, 'b, K, Q, V, S, A> Send for OccupiedEntryRef<'a, 'b, K, Q, V, S, A> where
K: Send,
Q: Sync + ?Sized,
V: Send,
S: Send,
A: Send + Allocator + Clone,
impl<Dyn> Send for DynMetadata<Dyn> where
Dyn: ?Sized,
impl<T> !Send for *const T where
T: ?Sized,
impl<T> !Send for *mut T where
T: ?Sized,
impl<T> !Send for NonNull<T> where
T: ?Sized,
NonNull
pointers are not Send
because the data they reference may be aliased.