New async iterators should be able to implement only `next(isolation:)` and
get the older `next()` implementation via a default. Implement the
appropriate default witness.
Fixes rdar://125447861.
To preserve compatibility with older compilers that do not allow `IsolatedAny`
to be enabled in production compilers, use an alias experimental feature when
building the stdlib (`IsolatedAny2`).
Also, add `@_allowFeatureSuppression(IsolatedAny)` in a couple spots it was
forgotten.
Partially resolves rdar://125138945
Associated type inference ought to take care of providing the `Failure`
typealias for these `AsyncIteratorProtocol` types. However, the inferred
typealias is printed with `@_implements` in the `.swiftinterface`, guarded with
the `$AssociatedTypeImplements` language feature guard, which means older
compilers cannot see the typealias and therefore think the conformance is
incomplete. To make sure the `_Concurrency` module's interface is backward
compatible, we must manually define these typealiases temporarily.
Part of rdar://125138945
can be reentrantly executed.
I don't think doing this is *actually a good idea*, but corrupting the
runtime is an even worse idea, and the overhead here is very low.
language feature, and suppress it for `Clock.measure`.
This allows the _Concurrency swiftinterface file to continue building with
compilers that do not support `OptionalIsolatedParameters`. The feature
suppression drops the `isolated` keyword and replaces `#isolation` with
`nil`.
Since `withoutActuallyEscaping()` has adopted typed throws, it's no longer
visible to older compilers that do not support typed throws. We need to guard
use of the function in inlinable code to make sure the textual interface of
`_Concurrency` remains buildable with older compilers.
Resolves rdar://124352900
We can't use os_log functionality in logd, diagnosticd, or notifyd. Check for them and disable tracing in those processes.
Add a new TracingCommon.h for common code shared between swiftCore and swift_Concurrency tracing. Add a single function that checks if tracing should be enabled, which now checks if os_signpost_enabled is available, and if the process is one of these. Modify the tracing code to check this before creating os_log objects.
rdar://124226334
This has been the behavior of the runtime since the initial release.
Initially, it was thought that task executors would provide similar
functionality, so they naturally took over the enumerator. After that
changed, we forgot to change it back. Fortunately, we haven't released
any versions of Swift with the task executors feature yet, so it's not
too late to fix this.
When building the Swift standard library, the compiler warns:
```
warning: capture of 'wordPtr' with non-sendable type 'UnsafeMutablePointer<Builtin.Word>' in a `@Sendable` closure
```
This diagnostic will become an error in the Swift 6 language mode, so it needs
to be addressed. This PR factors the atomic operations used by the
implementation of `Task.sleep()` into an `@unchecked Sendable` wrapper in order
to convince the compiler that these operations are thread-safe. As an added
benefit, the code is more readable when the atomic operatios are abstracted
away. This refactor intentionally translates the existing implementation into a
wrapper as faithfully as possible and does not attempt to improve on any other
aspects of the implementation, such as the unsafe manual memory allocation and
deallocation.
At the type that I introduced type throws into AsyncSequence and its
algorithms, I accidentally dropped a `@preconcurrency` on the ABI
entrypoint, leading to a mangled name change.
Fixes rdar://123639030.
The name of the `TaskExecutor` protocol was recently changed to remove
underscores after the feature was accepted in Swift Evolution. An implication
of that rename is that the `buildOrdinaryTaskExecutorRef` builtin changed
the type that it expected as the argument. However, the original change
landed in the standard library which as since produced swiftinterfaces
that contain the following inlinable code:
```
@inlinable public init<E>(ordinary executor: __shared E) where E : _Concurrency._TaskExecutor {
#if $BuiltinBuildTaskExecutor
self.executor = Builtin.buildOrdinaryTaskExecutorRef(executor)
#else
fatalError("Swift compiler is incompatible with this SDK version")
#endif
}
```
When a compiler containing the protocol rename attempts to type check the
above inlinable code, it crashes because the builtin is expecting an argument
conforming to `TaskExecutor`, which doesn't exist in this version of the
standard library. The issue is that the current compiler still supports
the `$BuiltinBuildTaskExecutor` feature guard, but the builtin supported
has since changed.
To resolve this issue, we need to stop supporting the `$BuiltinBuildTaskExecutor`
feature guard and introduce a new one that is only supported by compiler versions
that contain the rename. This approach relies on nothing having adopted the
API, otherwise we would need to stage in the rename as a parallel set of APIs,
and only remove the old APIs once nothing is relying on the old _Concurrency
swiftinterfaces.
Don't delete the OS declaration of `exit` because the concurrency shims aren't always imported, and so the shim declaration might not always be available.
Don't override the OS declaration of `exit` in the concurrency shims since we can't just delete the OS one. Instead, set up internal shims just for building Concurrency that forward declares `exit`.
