Under discussion as part of an amendment to SE-0466, limit default main
actor inference so it doesn't apply to a nested type within a
nonisolated type.
With `NonisolatedNonsendingByDefault` an explicit `nonisolated`
attribute in declaration context is inferred to mean `nonisolated(nonsending)`
and it should be printed as such in interface files and other places.
The inference logic that did didn't remove the original attribute
which meant that it would be printed twice i.e.
`nonisolated nonisolated(nonsending) func test() async` which is
incorrect and would fail swift interface validation.
Resolves: rdar://155847011
(cherry picked from commit b519c07428)
Completion can end up calling into pre-checking multiple times in
certain cases, make sure we don't attempt to fold a SequenceExpr
multiple times since its original AST is in a broken state
post-folding. Instead, just return the already-folded expression.
rdar://133717866
When checking whether a capture of a metatype is Sendable, we had an
incomplete and incorrect check for SendableMetatype conformance.
Replace that with the proper "prohibits isolated conformances" check
on the generic signature, which matches what we do on the caller side.
Fixes issue #82905 / rdar://155399531.
The compiler shouldn't accept mismatch in explicit isolation attributes
because it could lead to incorrect isolation selection.
Resolves: rdar://155589753
(cherry picked from commit a9373c0f3f)
The reason why this failed is that concurrently to @xedin landing
79af04ccc4, I enabled
NonisolatedNonsendingByDefault on a bunch of other tests. That change broke the
test and so we needed to fix it.
This commit fixes a few issues that were exposed:
1. We do not propagate nonisolated(nonsending) into a closure if its inferred
context isolation is global actor isolated or if the closure captures an
isolated parameter. We previously just always inferred
nonisolated(nonsending). Unfortunately since we do not yet have capture
information in CSApply, this required us to put the isolation change into
TypeCheckConcurrency.cpp and basically have function conversions of the form:
```
(function_conversion_expr type="nonisolated(nonsending) () async -> Void"
(closure_expr type="() async -> ()" isolated_to_caller_isolation))
```
Notice how we have a function conversion to nonisolated(nonsending) from a
closure expr that has an isolation that is isolated_to_caller.
2. With this in hand, we found that this pattern caused us to first thunk a
nonisolated(nonsending) function to an @concurrent function and then thunk that
back to nonisolated(nonsending), causing the final function to always be
concurrent. I put into SILGen a peephole that recognizes this pattern and emits
the correct code.
3. With that in hand, we found that we were emitting nonisolated(nonsending)
parameters for inheritActorContext functions. This was then fixed by @xedin in
With all this in hand, closure literal isolation and all of the other RBI tests
with nonisolated(nonsending) enabled pass.
rdar://154969621
(cherry picked from commit 648bb8fe30)
When synthesizing code for Codable conformances involving unsafe types,
make sure to wrap the resulting expressions in "unsafe" when strict memory safety is enabled.
Tweak the warning-emission logic to suppress warnings about spurious
"unsafe" expressions when the compiler generated the "unsafe" itself,
so we don't spam the developer with warnings they can't fix. Also make
the checking for other suppression considerations safe when there are
no source locations, eliminating a potential assertion.
Fixes rdar://153665692.
The `$generator` variable we create for the async for..in loop is
`nonisolated(unsafe)`, so ensure that we generate an `unsafe`
expression when we use it. This uncovered some inconsistencies in how
we do `unsafe` checking for for..in loops, so fix those.
Fixes rdar://154775389.
(cherry picked from commit 35628cb503)
We were effectively working around this previously at the SIL level. This caused
us not to obey the semantics of the actual evolution proposal. As an example of
this, in the following, x should not be considered main actor isolated:
```swift
nonisolated(nonsending) func useValue<T>(_ t: T) async {}
@MainActor func test() async {
let x = NS()
await useValue(x)
print(x)
}
```
we should just consider this to be a merge and since useValue does not have any
MainActor isolated parameters, x should not be main actor isolated and we should
not emit an error here.
I also fixed a separate issue where we were allowing for parameters of
nonisolated(nonsending) functions to be passed to @concurrent functions. We
cannot allow for this to happen since the nonisolated(nonsending) parameters
/could/ be actor isolated. Of course, we have lost that static information at
this point so we cannot allow for it. Given that we have the actual dynamic
actor isolation information, we could dynamically allow for the parameters to be
passed... but that is something that is speculative and is definitely outside of
the scope of this patch.
rdar://154139237
(cherry picked from commit c12c99fb73)
Cherry pick of #82370 to 6.2 branch.
---
* **Explanation**: Resolves an issue where sema is flagging inout
expressions in expression macros as invalid, setting up a catch 22 where
Sema emits an error when a parameter has the '&' sigil and type checking
fails when it doesn't.
* **Risk**: Low. It allows inout expressions in one additional context.
* **Testing**: Tested by lit tests, including new tests for the newly
allowed expression.
* **Issue**: rdar://153840234
* **Reviewer**: @slavapestov
* **Main branch PR**: https://github.com/swiftlang/swift/pull/82370
SILGen already has an exception for this from -enable-actor-data-race-checks,
so there's no need for it, and it causes problems in actor inits.
Fixes rdar://155239032
Forming an isolated conformance to a SendableMetatype-inherting
protocol opens up a soundness hole any time the conformance is used.
Reword the recently-introduced diagnostic for this case and promote it
to an error (except when it's preconcurrency).
Fixes rdar://154808002.
An isolated conformance to a SendableMetatype-inheriting protocol
cannot actually be used in generic code, because the SendableMetatype
requirement itself prevents it. Warn about this case so folks aren't
surprised at runtime.
This is a part of issue #82550 / rdar://154437489.
@cdecl enums are Swift enums representable in C. These enums must have
an integer raw type. They can be referenced from @cdecl functions and
@objc methods. @objc enums are still rejected from @cdecl functions.
This implements basic checks on the validity of the @cdecl attribute and
ensures the parameters and result types are representable in C. Many
more diagnostics will need to be updated to verify full representability
in C.
`TypeSimplifier` may not eliminate type variables from e.g the
pattern types of pattern expansion types since they can remain
unresolved due to e.g having a placeholder count type. Make sure we
eliminate any remaining type variables along with the placeholders.
There's probably a more principled fix here, but this is a quick and
low risk fix we can hopefully take for 6.2.
rdar://154954995
Currently only declarations would get `nonisolated(nonsending)`
inferred if the upcoming flag is enabled, this changes extend
this to apply to asynchronous nonisolated function types as well.
Resolves: rdar://154808850
(cherry picked from commit bb0cd6f0a6)
We can't assume that type-checking the expression macro in the
parameter will also fail if it fails at the call site since e.g
name lookup may differ. Make sure we only apply this logic to simple
literals.
rdar://154771596
