The `@abi` checker ignores uses of marker protocols, as they don’t have any impact on call compatibility. Add tests to ensure that this rule encompasses SE-0470’s `SendableMetatype`.
Fixes rdar://152602566.
- Extend `@_inheritActorContext` attribute to support optional `always` modifier.
The new modifier will make closure context isolated even if the parameter is not
captured by the closure.
- Implementation `@_inheritActorContext` attribute validation - it could only be
used on parameter that have `@Sendable` or `sending` and `@isolated(any)` or
`async` function type (downgraded to a warning until future major Swift mode
to avoid source compatibility issues).
- Add a new language feature that guards use of `@_inheritActorContext(always)` in swift interface files
- Update `getLoweredLocalCaptures` to add an entry for isolation parameter implicitly captured by `@_inheritActorContext(always)`
- Update serialization code to store `always` modifier
(cherry picked from commit 04d46760bb)
(cherry picked from commit c050e8f75a)
(cherry picked from commit c0aca5384b)
(cherry picked from commit a4f6d710cf)
(cherry picked from commit 6c911f5d42)
(cherry picked from commit 17b8f7ef12)
This includes changing the feature name so that compilers with the experimental feature don’t accidentally pick up content that only works in the final version.
Resolves rdar://150065196.
It has indirect effects on the accessors, so it shouldn’t matter, but we can defensively redirect the query to the API counterpart anyway.
This was the last `InferredInABIAttr` attribute, so we can now remove all of the infrastructure involved in supporting attribute inference.
Inlinability doesn’t affect the mangling except in function specializations, which are applied after the fact and should never mangle in information from an ABI-only decl. That means we can simply ban these from `@abi` instead of inferring them.
Also adds some assertions to help double-check that SIL never tries to directly mangle or retrieve inlinability info from an ABI-only decl.
SwiftSyntaxParser is already doing this, and we already diagnosed it in Sema anyway, so we’re just moving that diagnostic earlier so the ASTGen testing mode is happy. Also adding compiler tests for it.
Macro-related tests are not included in this commit; they require matching swift-syntax changes which are being negotiated.
CustomAttr backs four different features, each of which requires a different behavior in `@abi`:
• Global actors: Permitted (and permitted to vary) since they can affect mangling
• Result builders: Forbidden inside an `@abi` since they have no ABI impact
• Property wrappers: Forbidden both inside an `@abi` and on a decl with an `@abi` since it’s not clear how we would apply `@abi` to the auxiliary decls
• Attached macros: Forbidden inside an `@abi` since an ABI-only decl has no body, accessors, members, peers, extensions, or (currently) conformances
Implement these behaviors (outside of `ABIDeclChecker` since they can’t be described there).
Macro-related tests are not included in this commit; they require matching swift-syntax changes which are being negotiated.
A same-type constraint in an enclosing `where` clause will eliminate a generic parameter’s ABI impact. Teach `ABIDeclChecker::checkType()` about this so it can handle a known-unsupported case for `Swift.Result.init(catching:)`.
This commit compares the attributes on the decl inside the `@abi` attribute to those in the decl it’s attached to, diagnosing ABI-incompatible differences. It also rejects many attributes that don’t need to be specified in the `@abi` attribute, such as ObjC-ness, access control, or ABI-neutral traits like `@discardableResult`, so developers know to remove them.
This commit compares the decl inside the `@abi` attribute to the decl it’s attached to, diagnosing ABI-incompatible differences. It does not yet cover attributes, which are a large undertaking.
Check for:
• Matching decl kinds
• Matching PBD shapes (does every VarDecl on both sides have a counterpart?)
• Matching function effects
• Matching function arity (roughly)
Sema now type-checks the alternate ABI-providing decls inside of @abi attributes.
Making this work—particularly, making redeclaration checking work—required making name lookup aware of ABI decls. Name lookup now evaluates both API-providing and ABI-providing declarations. In most cases, it will filter ABI-only decls out unless a specific flag is passed, in which case it will filter API-only decls out instead. Calls that simply retrieve a list of declarations, like `IterableDeclContext::getMembers()` and friends, typically only return API-providing decls; you have to access the ABI-providing ones through those.
As part of that work, I have also added some basic compiler interfaces for working with the API-providing and ABI-providing variants. `ABIRole` encodes whether a declaration provides only API, only ABI, or both, and `ABIRoleInfo` combines that with a pointer to the counterpart providing the other role (for a declaration that provides both, that’ll just be a pointer to `this`).
Decl checking of behavior specific to @abi will come in a future commit.
Note that this probably doesn’t properly exercise some of the new code (ASTScope::lookupEnclosingABIAttributeScope(), for instance); I expect that to happen only once we can rename types using an @abi attribute, since that will create distinguishable behavior differences when resolving TypeReprs in other @abi attributes.
This attribute will allow you to specify an alternate version of the declaration used for mangling. It will allow minor adjustments to be made to declarations so long as they’re still compatible at the calling convention level, such as refining isolation or sendability, renaming without breaking ABI, etc.
The attribute is behind the experimental feature flag `ABIAttribute`.
