Trait wasmer_types::lib::std::marker::Sync 1.0.0[−][src]
pub unsafe auto trait Sync { }
Expand description
Types for which it is safe to share references between threads.
This trait is automatically implemented when the compiler determines it’s appropriate.
The precise definition is: a type T
is Sync
if and only if &T
is
Send
. In other words, if there is no possibility of
undefined behavior (including data races) when passing
&T
references between threads.
As one would expect, primitive types like u8
and f64
are all Sync
, and so are simple aggregate types containing them,
like tuples, structs and enums. More examples of basic Sync
types include “immutable” types like &T
, and those with simple
inherited mutability, such as Box<T>
, Vec<T>
and
most other collection types. (Generic parameters need to be Sync
for their container to be Sync
.)
A somewhat surprising consequence of the definition is that &mut T
is Sync
(if T
is Sync
) even though it seems like that might
provide unsynchronized mutation. The trick is that a mutable
reference behind a shared reference (that is, & &mut T
)
becomes read-only, as if it were a & &T
. Hence there is no risk
of a data race.
Types that are not Sync
are those that have “interior
mutability” in a non-thread-safe form, such as Cell
and RefCell
. These types allow for mutation of
their contents even through an immutable, shared reference. For
example the set
method on Cell<T>
takes &self
, so it requires
only a shared reference &Cell<T>
. The method performs no
synchronization, thus Cell
cannot be Sync
.
Another example of a non-Sync
type is the reference-counting
pointer Rc
. Given any reference &Rc<T>
, you can clone
a new Rc<T>
, modifying the reference counts in a non-atomic way.
For cases when one does need thread-safe interior mutability,
Rust provides atomic data types, as well as explicit locking via
sync::Mutex
and sync::RwLock
. These types
ensure that any mutation cannot cause data races, hence the types
are Sync
. Likewise, sync::Arc
provides a thread-safe
analogue of Rc
.
Any types with interior mutability must also use the
cell::UnsafeCell
wrapper around the value(s) which
can be mutated through a shared reference. Failing to doing this is
undefined behavior. For example, transmute
-ing
from &T
to &mut T
is invalid.
See the Nomicon for more details about Sync
.
Implementations on Foreign Types
impl Sync for Argument
impl Sync for FormatSpec
impl Sync for Alignment
impl Sync for Count
impl<T> Sync for Key<T>
[src]
impl<T> Sync for SyncOnceCell<T> where
T: Sync + Send,
[src]
T: Sync + Send,
impl<T> Sync for JoinHandle<T>
[src]
impl !Sync for Args
[src]
impl<'a> Sync for IoSlice<'a>
[src]
impl !Sync for ArgsOs
[src]
impl<T, F> Sync for SyncLazy<T, F> where
F: Send,
SyncOnceCell<T>: Sync,
[src]
F: Send,
SyncOnceCell<T>: Sync,
impl<'a> Sync for IoSliceMut<'a>
[src]
impl<T> !Sync for *mut T where
T: ?Sized,
[src]
T: ?Sized,
impl Sync for Waker
[src]
impl<T> !Sync for *const T where
T: ?Sized,
[src]
T: ?Sized,
impl<'_, T> Sync for Cursor<'_, T> where
T: Sync,
[src]
T: Sync,
impl<T> Sync for LinkedList<T> where
T: Sync,
[src]
T: Sync,
impl<'_, T> Sync for Drain<'_, T> where
T: Sync,
[src]
T: Sync,
impl<'_, T> Sync for IterMut<'_, T> where
T: Sync,
[src]
T: Sync,
impl<'_, T> Sync for Iter<'_, T> where
T: Sync,
[src]
T: Sync,
impl<'_, T> Sync for IterMut<'_, T> where
T: Sync,
[src]
T: Sync,
impl<'_, T> Sync for CursorMut<'_, T> where
T: Sync,
[src]
T: Sync,
impl<'_, K, V> Sync for OccupiedEntry<'_, K, V> where
K: Sync,
V: Sync,
[src]
K: Sync,
V: Sync,
impl<'_, T> Sync for RawDrain<'_, T> where
T: Sync,
T: Sync,
impl<'_, K, V, S> Sync for RawOccupiedEntryMut<'_, K, V, S> where
K: Sync,
V: Sync,
S: Sync,
K: Sync,
V: Sync,
S: Sync,
impl<T> Sync for RawTable<T> where
T: Sync,
T: Sync,
impl<'_, K, V, S> Sync for OccupiedEntry<'_, K, V, S> where
K: Sync,
V: Sync,
S: Sync,
K: Sync,
V: Sync,
S: Sync,
impl<T> Sync for RawIntoIter<T> where
T: Sync,
T: Sync,
impl Sync for AlignedVec
[src]
impl<Dyn> Sync for DynMetadata<Dyn> where
Dyn: ?Sized,
Dyn: ?Sized,
impl Sync for isize
impl<T> Sync for [T] where
T: Sync,
T: Sync,
impl Sync for [u8]
impl Sync for char
impl Sync for u128
impl Sync for u16
impl Sync for i128
impl Sync for i16
impl Sync for str
impl Sync for f64
impl Sync for u64
impl Sync for u8
impl Sync for i64
impl Sync for i8
impl<T, const N: usize> Sync for [T; N] where
T: Sync,
T: Sync,
impl Sync for bool
impl Sync for f32
impl Sync for u32
impl Sync for usize
impl Sync for i32
Implementors
impl Sync for AtomicBool
[src]
impl Sync for AtomicI8
1.34.0[src]
impl Sync for AtomicI16
1.34.0[src]
impl Sync for AtomicI32
1.34.0[src]
impl Sync for AtomicI64
1.34.0[src]
impl Sync for AtomicIsize
[src]
impl Sync for AtomicU8
1.34.0[src]
impl Sync for AtomicU16
1.34.0[src]
impl Sync for AtomicU32
1.34.0[src]
impl Sync for AtomicU64
1.34.0[src]
impl Sync for AtomicUsize
[src]
impl Sync for wasmer_types::lib::std::sync::Once
[src]
impl<'_> Sync for wasmer_types::lib::std::string::Drain<'_>
1.6.0[src]
impl<'_, T> Sync for wasmer_types::lib::std::slice::Iter<'_, T> where
T: Sync,
[src]
T: Sync,
impl<'_, T> Sync for wasmer_types::lib::std::slice::IterMut<'_, T> where
T: Sync,
[src]
T: Sync,
impl<'_, T> Sync for MutexGuard<'_, T> where
T: Sync + ?Sized,
1.19.0[src]
T: Sync + ?Sized,
impl<'_, T> Sync for RwLockReadGuard<'_, T> where
T: Sync + ?Sized,
1.23.0[src]
T: Sync + ?Sized,
impl<'_, T> Sync for RwLockWriteGuard<'_, T> where
T: Sync + ?Sized,
1.23.0[src]
T: Sync + ?Sized,
impl<'_, T, A> Sync for wasmer_types::lib::std::vec::Drain<'_, T, A> where
T: Sync,
A: Sync + Allocator,
1.6.0[src]
T: Sync,
A: Sync + Allocator,
impl<Dyn> Sync for wasmer_types::lib::std::ptr::DynMetadata<Dyn> where
Dyn: ?Sized,
[src]
Dyn: ?Sized,
impl<T> !Sync for Cell<T> where
T: ?Sized,
[src]
T: ?Sized,
impl<T> !Sync for RefCell<T> where
T: ?Sized,
[src]
T: ?Sized,
impl<T> !Sync for UnsafeCell<T> where
T: ?Sized,
[src]
T: ?Sized,
impl<T> !Sync for NonNull<T> where
T: ?Sized,
1.25.0[src]
T: ?Sized,
NonNull
pointers are not Sync
because the data they reference may be aliased.
impl<T> !Sync for Rc<T> where
T: ?Sized,
[src]
T: ?Sized,
impl<T> !Sync for wasmer_types::lib::std::rc::Weak<T> where
T: ?Sized,
1.4.0[src]
T: ?Sized,
impl<T> !Sync for Receiver<T>
[src]
impl<T> !Sync for Sender<T>
[src]
impl<T> Sync for Empty<T>
1.42.0[src]
impl<T> Sync for AtomicPtr<T>
[src]
impl<T> Sync for Arc<T> where
T: Sync + Send + ?Sized,
[src]
T: Sync + Send + ?Sized,
impl<T> Sync for Mutex<T> where
T: Send + ?Sized,
[src]
T: Send + ?Sized,
impl<T> Sync for RwLock<T> where
T: Send + Sync + ?Sized,
[src]
T: Send + Sync + ?Sized,
impl<T> Sync for wasmer_types::lib::std::sync::Weak<T> where
T: Sync + Send + ?Sized,
1.4.0[src]
T: Sync + Send + ?Sized,
impl<T, A> Sync for wasmer_types::lib::std::vec::IntoIter<T, A> where
T: Sync,
A: Allocator,
[src]
T: Sync,
A: Allocator,
Auto implementors
impl !Sync for ExternRef
impl !Sync for VMExternRef
impl !Sync for OnceState
impl Sync for ExportIndex
impl Sync for ExternType
impl Sync for GlobalInit
impl Sync for ImportIndex
impl Sync for Mutability
impl Sync for Type
impl Sync for wasmer_types::lib::std::cmp::Ordering
impl Sync for Infallible
impl Sync for wasmer_types::lib::std::fmt::Alignment
impl Sync for wasmer_types::lib::std::sync::atomic::Ordering
impl Sync for RecvTimeoutError
impl Sync for TryRecvError
impl Sync for Atomically
impl Sync for Bytes
impl Sync for CustomSectionIndex
impl Sync for DataIndex
impl Sync for DataInitializerLocation
impl Sync for ElemIndex
impl Sync for Features
impl Sync for FunctionIndex
impl Sync for FunctionType
impl Sync for GlobalIndex
impl Sync for GlobalType
impl Sync for LocalFunctionIndex
impl Sync for LocalGlobalIndex
impl Sync for LocalMemoryIndex
impl Sync for LocalTableIndex
impl Sync for MemoryIndex
impl Sync for MemoryType
impl Sync for OwnedDataInitializer
impl Sync for PageCountOutOfRange
impl Sync for Pages
impl Sync for SignatureIndex
impl Sync for TableIndex
impl Sync for TableInitializer
impl Sync for TableType
impl Sync for V128
impl Sync for TypeId
impl Sync for BorrowError
impl Sync for BorrowMutError
impl Sync for Error
impl Sync for SipHasher
impl Sync for RangeFull
impl Sync for FromUtf8Error
impl Sync for FromUtf16Error
impl Sync for String
impl Sync for RecvError
impl Sync for Barrier
impl Sync for BarrierWaitResult
impl Sync for Condvar
impl Sync for WaitTimeoutResult
impl Sync for PhantomPinned
impl<'a> !Sync for Arguments<'a>
impl<'a> !Sync for Formatter<'a>
impl<'a, 'b> !Sync for DebugList<'a, 'b>
impl<'a, 'b> !Sync for DebugMap<'a, 'b>
impl<'a, 'b> !Sync for DebugSet<'a, 'b>
impl<'a, 'b> !Sync for DebugStruct<'a, 'b>
impl<'a, 'b> !Sync for DebugTuple<'a, 'b>
impl<'a, B: ?Sized> Sync for Cow<'a, B> where
B: Sync,
<B as ToOwned>::Owned: Sync,
B: Sync,
<B as ToOwned>::Owned: Sync,
impl<'a, I, A> Sync for Splice<'a, I, A> where
A: Sync,
I: Sync,
<I as Iterator>::Item: Sync,
A: Sync,
I: Sync,
<I as Iterator>::Item: Sync,
impl<'a, K, V> Sync for wasmer_types::entity::Iter<'a, K, V> where
K: Sync,
V: Sync,
K: Sync,
V: Sync,
impl<'a, K, V> Sync for wasmer_types::entity::IterMut<'a, K, V> where
K: Sync,
V: Sync,
K: Sync,
V: Sync,
impl<'a, T> !Sync for wasmer_types::lib::std::sync::mpsc::Iter<'a, T>
impl<'a, T> !Sync for TryIter<'a, T>
impl<'a, T> Sync for Chunks<'a, T> where
T: Sync,
T: Sync,
impl<'a, T> Sync for ChunksExact<'a, T> where
T: Sync,
T: Sync,
impl<'a, T> Sync for ChunksExactMut<'a, T> where
T: Sync,
T: Sync,
impl<'a, T> Sync for ChunksMut<'a, T> where
T: Sync,
T: Sync,
impl<'a, T> Sync for RChunks<'a, T> where
T: Sync,
T: Sync,
impl<'a, T> Sync for RChunksExact<'a, T> where
T: Sync,
T: Sync,
impl<'a, T> Sync for RChunksExactMut<'a, T> where
T: Sync,
T: Sync,
impl<'a, T> Sync for RChunksMut<'a, T> where
T: Sync,
T: Sync,
impl<'a, T> Sync for Windows<'a, T> where
T: Sync,
T: Sync,
impl<'a, T, A = NonAtomically> !Sync for MemoryView<'a, T, A>
impl<'a, T, F, A> Sync for DrainFilter<'a, T, F, A> where
A: Sync,
F: Sync,
T: Sync,
A: Sync,
F: Sync,
T: Sync,
impl<'a, T, P> Sync for GroupBy<'a, T, P> where
P: Sync,
T: Sync,
P: Sync,
T: Sync,
impl<'a, T, P> Sync for GroupByMut<'a, T, P> where
P: Sync,
T: Sync,
P: Sync,
T: Sync,
impl<'a, T, P> Sync for RSplit<'a, T, P> where
P: Sync,
T: Sync,
P: Sync,
T: Sync,
impl<'a, T, P> Sync for RSplitMut<'a, T, P> where
P: Sync,
T: Sync,
P: Sync,
T: Sync,
impl<'a, T, P> Sync for RSplitN<'a, T, P> where
P: Sync,
T: Sync,
P: Sync,
T: Sync,
impl<'a, T, P> Sync for RSplitNMut<'a, T, P> where
P: Sync,
T: Sync,
P: Sync,
T: Sync,
impl<'a, T, P> Sync for Split<'a, T, P> where
P: Sync,
T: Sync,
P: Sync,
T: Sync,
impl<'a, T, P> Sync for SplitMut<'a, T, P> where
P: Sync,
T: Sync,
P: Sync,
T: Sync,
impl<'a, T, P> Sync for SplitN<'a, T, P> where
P: Sync,
T: Sync,
P: Sync,
T: Sync,
impl<'a, T, P> Sync for SplitNMut<'a, T, P> where
P: Sync,
T: Sync,
P: Sync,
T: Sync,
impl<'a, T, const N: usize> !Sync for ArrayWindows<'a, T, N>
impl<'a, T, const N: usize> Sync for ArrayChunks<'a, T, N> where
T: Sync,
T: Sync,
impl<'a, T, const N: usize> Sync for ArrayChunksMut<'a, T, N> where
T: Sync,
T: Sync,
impl<'b, T> !Sync for Ref<'b, T>
impl<'b, T> !Sync for RefMut<'b, T>
impl<'data> Sync for DataInitializer<'data>
impl<A> Sync for Repeat<A> where
A: Sync,
A: Sync,
impl<A, B> Sync for Chain<A, B> where
A: Sync,
B: Sync,
A: Sync,
B: Sync,
impl<A, B> Sync for Zip<A, B> where
A: Sync,
B: Sync,
A: Sync,
B: Sync,
impl<B, C> Sync for ControlFlow<B, C> where
B: Sync,
C: Sync,
B: Sync,
C: Sync,
impl<F> Sync for FromFn<F> where
F: Sync,
F: Sync,
impl<F> Sync for OnceWith<F> where
F: Sync,
F: Sync,
impl<F> Sync for RepeatWith<F> where
F: Sync,
F: Sync,
impl<H> Sync for BuildHasherDefault<H> where
H: Sync,
H: Sync,
impl<I> Sync for Cloned<I> where
I: Sync,
I: Sync,
impl<I> Sync for Copied<I> where
I: Sync,
I: Sync,
impl<I> Sync for Cycle<I> where
I: Sync,
I: Sync,
impl<I> Sync for Enumerate<I> where
I: Sync,
I: Sync,
impl<I> Sync for Flatten<I> where
I: Sync,
<<I as Iterator>::Item as IntoIterator>::IntoIter: Sync,
I: Sync,
<<I as Iterator>::Item as IntoIterator>::IntoIter: Sync,
impl<I> Sync for Fuse<I> where
I: Sync,
I: Sync,
impl<I> Sync for Intersperse<I> where
I: Sync,
<I as Iterator>::Item: Sync,
I: Sync,
<I as Iterator>::Item: Sync,
impl<I> Sync for Peekable<I> where
I: Sync,
<I as Iterator>::Item: Sync,
I: Sync,
<I as Iterator>::Item: Sync,
impl<I> Sync for Skip<I> where
I: Sync,
I: Sync,
impl<I> Sync for StepBy<I> where
I: Sync,
I: Sync,
impl<I> Sync for Take<I> where
I: Sync,
I: Sync,
impl<I, F> Sync for FilterMap<I, F> where
F: Sync,
I: Sync,
F: Sync,
I: Sync,
impl<I, F> Sync for Inspect<I, F> where
F: Sync,
I: Sync,
F: Sync,
I: Sync,
impl<I, F> Sync for Map<I, F> where
F: Sync,
I: Sync,
F: Sync,
I: Sync,
impl<I, G> Sync for IntersperseWith<I, G> where
G: Sync,
I: Sync,
<I as Iterator>::Item: Sync,
G: Sync,
I: Sync,
<I as Iterator>::Item: Sync,
impl<I, P> Sync for Filter<I, P> where
I: Sync,
P: Sync,
I: Sync,
P: Sync,
impl<I, P> Sync for MapWhile<I, P> where
I: Sync,
P: Sync,
I: Sync,
P: Sync,
impl<I, P> Sync for SkipWhile<I, P> where
I: Sync,
P: Sync,
I: Sync,
P: Sync,
impl<I, P> Sync for TakeWhile<I, P> where
I: Sync,
P: Sync,
I: Sync,
P: Sync,
impl<I, St, F> Sync for Scan<I, St, F> where
F: Sync,
I: Sync,
St: Sync,
F: Sync,
I: Sync,
St: Sync,
impl<I, U, F> Sync for FlatMap<I, U, F> where
F: Sync,
I: Sync,
<U as IntoIterator>::IntoIter: Sync,
F: Sync,
I: Sync,
<U as IntoIterator>::IntoIter: Sync,
impl<Idx> Sync for Range<Idx> where
Idx: Sync,
Idx: Sync,
impl<Idx> Sync for RangeFrom<Idx> where
Idx: Sync,
Idx: Sync,
impl<Idx> Sync for RangeInclusive<Idx> where
Idx: Sync,
Idx: Sync,
impl<Idx> Sync for RangeTo<Idx> where
Idx: Sync,
Idx: Sync,
impl<Idx> Sync for RangeToInclusive<Idx> where
Idx: Sync,
Idx: Sync,
impl<K> Sync for Keys<K> where
K: Sync,
K: Sync,
impl<K, V> Sync for BoxedSlice<K, V> where
K: Sync,
V: Sync,
K: Sync,
V: Sync,
impl<K, V> Sync for PrimaryMap<K, V> where
K: Sync,
V: Sync,
K: Sync,
V: Sync,
impl<K, V> Sync for SecondaryMap<K, V> where
K: Sync,
V: Sync,
K: Sync,
V: Sync,
impl<K, V> Sync for ArchivableIndexMap<K, V> where
K: Sync,
V: Sync,
K: Sync,
V: Sync,
impl<T> !Sync for Value<T>
impl<T> !Sync for wasmer_types::lib::std::sync::mpsc::IntoIter<T>
impl<T> Sync for Bound<T> where
T: Sync,
T: Sync,
impl<T> Sync for TryLockError<T> where
T: Sync,
T: Sync,
impl<T> Sync for TrySendError<T> where
T: Sync,
T: Sync,
impl<T> Sync for PackedOption<T> where
T: Sync,
T: Sync,
impl<T> Sync for ExportType<T> where
T: Sync,
T: Sync,
impl<T> Sync for ImportType<T> where
T: Sync,
T: Sync,
impl<T> Sync for Reverse<T> where
T: Sync,
T: Sync,
impl<T> Sync for wasmer_types::lib::std::iter::Once<T> where
T: Sync,
T: Sync,
impl<T> Sync for Rev<T> where
T: Sync,
T: Sync,
impl<T> Sync for Discriminant<T>
impl<T> Sync for SendError<T> where
T: Sync,
T: Sync,
impl<T> Sync for SyncSender<T> where
T: Send,
T: Send,
impl<T> Sync for PoisonError<T> where
T: Sync,
T: Sync,
impl<T> Sync for MaybeUninit<T> where
T: Sync,
T: Sync,
impl<T, A> Sync for Vec<T, A> where
A: Sync,
T: Sync,
A: Sync,
T: Sync,
impl<T, F> Sync for Successors<T, F> where
F: Sync,
T: Sync,
F: Sync,
T: Sync,
impl<T: ?Sized> Sync for ManuallyDrop<T> where
T: Sync,
T: Sync,
impl<T: ?Sized> Sync for PhantomData<T> where
T: Sync,
T: Sync,
impl<T: ?Sized, A> Sync for Box<T, A> where
A: Sync,
T: Sync,
A: Sync,
T: Sync,
impl<Y, R> Sync for GeneratorState<Y, R> where
R: Sync,
Y: Sync,
R: Sync,
Y: Sync,