This is very brittle in this first iteration. For now we require the
declaration representing the availability domain be deserialized before it can
be looked up by name since Clang does not have a lookup table for availabilty
domains in its module representation. As a result, it only works for bridging
headers that are not precompiled.
Part of rdar://138441266.
Instead of using the `isolated P` syntax, switch to specifying the
global actor type directly, e.g.,
class MyClass: @MainActor MyProto { ... }
No functionality change at this point
To pave the way for the new experimental feature which will operate on '@const' attribute and expand the scope of what's currently handled by '_const' without breaking compatibility, for now.
Allow a conformance to be "isolated", meaning that it stays in the same
isolation domain as the conforming type. Only allow this for
global-actor-isolated types.
When a conformance is isolated, a nonisolated requirement can be
witnessed by a declaration with the same global actor isolation as the
enclosing type.
We had an exploded form of conformance attributes (@unchecked,
@preconcurrency, @unsafe) at several different places in the compiler.
Pull these into a single structure so it's easier to manage and extend.
Should have done this a long time ago.
When `SendableCompletionHandlers` feature is enabled, ClangImporter
is going to inject `@Sendable` attribute into the completion handler
parameter's function type. We need to make sure that his new behavior
doesn't break shadowing rules and allow APIs to annotate their ObjC
declarations with `@Sendable` without breaking clients.
Typically, access control denies access to member implementations, so the imported interface decl will be used instead. However, in contexts that permit direct access to stored properties—such as accessors, inits, and deinits—their member implementations are accessible; the compiler then relies on a shadowing rule favoring Swift decls over ObjC decls to eliminate the imported interface decl.
However, there are many rules that are higher-priority than the Swift vs. ObjC decls one. In particular, a recent change to availability checking in #77886 caused a higher-priority rule to begin eliminating member implementations which belonged to unavailable extensions. This caused regressions in projects using `@objc @implementation` with classes that are unavailable in Mac Catalyst.
Introduce a fairly high-priority shadowing rule that favors a member implementation over its interface when both are present (i.e. when direct access to storage is permitted).
Fixes rdar://143582383.
MemberImportVisibility rules should only apply to source code in the main
module. The rules were being applied when resolving witnesses for synthesized
Hashable conformances on CF types imported by ClangImporter, which caused the
lookups to fail and bad conformances to be generated.
Resolves https://github.com/swiftlang/swift/issues/78870 and rdar://142433039.
Move the backtracing code into a new Runtime module. This means renaming
the Swift Runtime's CMake target because otherwise there will be a name
clash.
rdar://124913332
Protocol conformances have a handful attributes that can apply to them
directly, including @unchecked (for Sendable), @preconcurrency, and
@retroactive. Generalize this into an option set that we carry around,
so it's a bit easier to add them, as well as reworking the
serialization logic to deal with an arbitrary number of such options.
Use this generality to add support for @unsafe conformances, which are
needed when unsafe witnesses are used to conform to safe requirements.
Implement general support for @unsafe conformances, including
producing a single diagnostic per missing @unsafe that provides a
Fix-It and collects together all of the unsafe witnesses as notes.
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.
Introduce a number of fixes to allow us to fully use declarations that
are produced by applying a peer macro to an imported declarations.
These changes include:
* Ensuring that we have the right set of imports in the source file
containing the macro expansion, because it depends only on the module
it comes from
* Ensuring that name lookup looks in that file even when the
DeclContext hierarchy doesn't contain the source file (because it's
based on the Clang module structure)
Expand testing to be sure that we're getting the right calls,
diagnostics, and generated IR symbols.
When we replay a solution, we must record changes in the trail, so fix the
logic to do that. This fixes the first assertion failure with this test case.
The test case also exposed a second issue. We synthesize a CustomAttr in
applySolutionToClosurePropertyWrappers() with a type returned by simplifyType().
Eventually, CustomAttrNominalRequest::evaluate() looks at this type, and passes
it to directReferencesForType(). Unfortunately, this entry point does not
understand type aliases whose underlying type is a type parameter.
However, directReferencesForType() is the wrong thing to use here, and we
can just call getAnyNominal() instead.
Fixes rdar://139237781.
The Clang importer maps arbitrary attributes spelled with `swift_attr("...")`
over to Swift attributes, using the Swift parser to process those attributes.
Extend this mechanism to allow `swift_attr` to refer to an attached macro,
expanding that macro as needed.
When a macro is applied to an imported declaration, that declaration is
pretty-printed (from the C++ AST) to provide to the macro implementation.
There are a few games we need to place to resolve the macro, and a few more
to lazily perform pretty-printing and adjust source locations to get the
right information to the macro, but this demonstrates that we could
take this path.
As an example, we use this mechanism to add an `async` version of a C
function that delivers its result via completion handler, using the
`@AddAsync` example macro implementation from the swift-syntax
repository.
With the upcoming `MemberImportVisibility` feature enabled, code built with Cxx
interop also enabled could be rejected by the compiler with cryptic errors
about the `__ObjC` module not being imported. This is the result of a
surprising implementation detail of Cxx interop. When importing C++ namespaces
and their members, the Clang importer puts these declarations in the Clang
header import module (a.k.a. the bridging header module, `__ObjC`). C++
namespaces don't have a logical modular home in the Swift AST because they can
span multiple modules, so it's understandable why this implementation was
chosen. However, the concrete members of namespaces also get placed in the
`__ObjC` module too, and this really confuses things.
To work around this idiosyncrasy of Cxx interop, I've introduced
`Decl::getModuleContextForNameLookup()` which returns the module that a
declaration would ideally belong to if Cxx interop didn't have this behavior.
This alternative to `Decl::getModuleContext()` is now used everywhere that
`MemberImportVisibility` rules are enforced to provide consistency.
Additionally, I found that I also had to further special-case the header import
module for Cxx interop because it turns out that there are some additional
declarations, beyond imported namespaces, that also live there and need to be
implicitly visible in every source file. The `__ObjC` module is not implicitly
imported in source files when Cxx interop is enabled, so these declarations are
not deemed visible under normal name lookup rules. When I tried to add an
implicit import of `__ObjC` when Cxx interop is enabled, it broke a bunch
tests. So for now, when a decl really belongs to the `__ObjC` module in Cxx
interop mode, we just always allow it to be referenced.
This Cxx interop behavior really needs a re-think in my opinion, but that will
require larger discussions.
Resolves rdar://136600598.
Previously, the constraint solver would first attempt member lookup that
excluded members from transitively imported modules. If there were no viable
candidates, it would perform a second lookup that included the previously
excluded members, treating any candidates as unviable. This meant that if the
member reference did resolve to one of the unviable candidates the resulting
AST would be broken, which could cause unwanted knock-on diagnostics.
Now, members from transitively imported modules are always returned in the set
of viable candidates. However, scoring will always prioritize candidates from
directly imported modules over members from transitive imports. This solves the
ambiguities that `MemberImportVisibility` is designed to prevent. If the only
viable candidates are from transitively imported modules, though, then the
reference will be resolved successfully and diagnosed later in
`MiscDiagnostics.cpp`. The resulting AST will not contain any errors, which
ensures that necessary access levels can be computed correctly for the imports
suggested by `MemberImportVisibility` fix-its.
Resolves rdar://126637855.
Some requirement machine work
Rename requirement to Value
Rename more things to Value
Fix integer checking for requirement
some docs and parser changes
Minor fixes
If an `ExtendedNominalRequest`'s initial type lookup yields no results, query
again ignoring missing imports to find nominals that were excluded due to the
`MemberImportVisibility` feature being enabled. The missing import will be
diagnosed during type resolution and allowing the request to succeed enables
better diagnostics.
Part of rdar://126637855.
In existing Swift, an `@_exported import` in any source file makes the
declarations from the imported module visible in all source files. It's unclear
whether this is an explicit decision or is simply and unintended consequence of
effectively adding an implicit import to each source file for the module being
compiled.
Although it's not clear whether this behavior is desirable, the behavior of
member lookup when the MemberImportVisibility feature is enabled should align
with it in order to avoid causing unnecessary churn in required imports.
Resolves rdar://132525152.
Control enforcement of member import visibility requirements via a new option,
instead of piggy-backing on the existing IgnoreAccessControl option. Adopt the
option when doing fallback lookups for unviable members so that the compiler
can diagnose the reason that a member is inaccessible more reliably.
Previously, with MemberImportVisibility enabled decls with the package access
level could be mis-diagnosed as inaccessible due to their access level when
really they were inaccessible due to a missing import.
Resolves rdar://131501862.
Remove `deque` from files it isn't actually used in. Add it and `stack`
to files that it is - presumably they were previously transitively found
through other includes.
Out of an abundance of caution, we:
1. Left in parsing support for transferring but internally made it rely on the
internals of sending.
2. Added a warning to tell people that transferring was going to
be removed very soon.
Now that we have given people some time, remove support for parsing
transferring.
rdar://130253724
Although I don't plan to bring over new assertions wholesale
into the current qualification branch, it's entirely possible
that various minor changes in main will use the new assertions;
having this basic support in the release branch will simplify that.
(This is why I'm adding the includes as a separate pass from
rewriting the individual assertions)
