Thanks to a great idea from Slava, simplify the printing of marker
protocols in Swift interfaces while maintaining backward compatibility.
For compilers that cannot handle marker protocols, print a typealias
to `Any` instead, which is a good stand-in for just about everything.
diag::warning_module_shadowing_may_break_module_interface was *enormous* but still described the problem too tersely to convey everything that was needed. Instead, reference a bug report that describes the problem and its workarounds in more detail.
There is a known issue with module interfaces where a type with the same name as a module will disrupt references to types in that module. Fully fixing it will require a new language feature (SR-898) which is not yet available. In the meantime, module interfaces support a workaround flag (“-Xfrontend -module-interface-preserve-types-as-written”) which prints an alternate form that usually works. However, you have to know to add this flag, and it’s not obvious because nothing breaks until a compiler tries to consume the affected module interface (or sometimes even one of its clients).
This commit emits a warning during module interface emission whenever the module interface either imports a type with the same name as the module being built, or declares a type with the same name as a visible module. This lets the user know that the type may cause problems and they might need to implement a workaround.
The check that limited inference of actor isolation meant that we were
incorrectly computing actor isolation for (e.g.) overrides when
parsing from Swift interfaces. Only limit inference for cases where we
are guaranteed to synthesize an attribute by inference.
This patch updates the `actor class` spelling to `actor` in almost all
of the tests. There are places where I verify that we sanely handle
`actor` as an attribute though. These include:
- test/decl/class/actor/basic.swift
- test/decl/protocol/special/Actor.swift
- test/SourceKit/CursorInfo/cursor_info_concurrency.swift
- test/attr/attr_objc_async.swift
- test/ModuleInterface/actor_protocol.swift
When generating a module interface, emit `#if` around any declarations
that are tied to specific, named language features. This allows module
interfaces to be processed by older Swift compilers that do not
support these newer features, such as async/await or actors.
The amount of effort required to correctly handle a new kind of
feature varies somewhat drastically based on the feature itself. The
"simple" case is where a particular declaration can only exist if a
feature is available. For example, and `async` declaration is fairly
easy to handle; a `@_marker` protocol's conformances are not.
Fixes rdar://73326633.
`InterfaceSubContextDelegateImpl` causes sub-instances to inherit `-fmodule-map-file=` options.
Those Module Maps become file dependencies of all downstream PCMs and their depending Swift modules, even though they really aren't.
This causes frequent re-builds of the Module Cache contents when seemingly-unrelated files are touched.
Explicit Module Builds rely on these options for building Swift Interface files, so for now we just disable inheritance of these options in Implicit Module builds.
The error shown when the compiler fails to build a module from its
textual interface has been creating some confusion. This is a proposal
to make it more useful to the programmer not working in the SDK, insist
on looking at the previous errors first, put less emphasis on possible
compiler bugs, and always show alternatives to the incompatible
compilers issue as this is the most common case now.
Availability macros passed via the frontend flag -define-availability
should be accepted by @_originallyDefinedIn where they behave as they do
in @available.
rdar://72354787
swift-driver passes down an SDK version number with a non-existing build number as 0.
The compiler should be resilient to this so we can locate prebuilt module cache.
rdar://72230172
Protocol requirements declared as a function with a result-builder
custom attribute should keep that attribute in the generated textual
swiftinterface file.
rdar://72063255
Passing the frontend flag -Rmodule-loading makes the compiler emit
remarks with the path of every module loaded. The path for Swift modules
is either the swiftinterface file for modules built with library
evolution or the binary swiftmodule otherwise. The path for clangmodules
is always in the cache which could be improved as it may be less useful.
Here's an extract of the output for a simple SwiftUI app:
<unknown>:0: remark: loaded module from
/Users/xymus/Library/Developer/Xcode/DerivedData/ModuleCache.noindex/2VJP7CNCGWRF0/SwiftShims-18ZF6992O9H75.pcm
<unknown>:0: remark: loaded module from
/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator14.2.sdk/usr/lib/swift/Swift.swiftmodule/x86_64-apple-ios-simulator.swiftinterface
<unknown>:0: remark: loaded module from
/Users/xymus/Library/Developer/Xcode/DerivedData/ModuleCache.noindex/2VJP7CNCGWRF0/os-1HVC6DNXVU37C.pcm
<unknown>:0: remark: loaded module from
/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator14.2.sdk/usr/lib/swift/os.swiftmodule/x86_64-apple-ios-simulator.swiftinterface
<unknown>:0: remark: loaded module from
/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator14.2.sdk/System/Library/Frameworks/SwiftUI.framework/Modules/SwiftUI.swiftmodule/x86_64-apple-ios-simulator.swiftinterface
Including all the system header dependencies and `stat`ing them all the time introduces significant performance overhead for normal compilation, and other features like code-completion, without being worth it in practice.
Maintain the ability for older Swift compilers to read .swiftinterfaces
that make use of result builders by always emitting @_functionBuilder
rather than the newer @resultBuilder.
"Function builders" are being renamed to "result builders". Add the
corresponding `@resultBuilder` attribute, with `@_functionBuilder` as
an alias for it, Update test cases to use @resultBuilder.
When we infer an actor-isolation attribute on a declaration, add an
implicit attribute that will show up in the printed interface and get
serialized.
... and clean up the type resolution logic for global actor attributes
to make it use CustomAttrTypeRequest, so the result gets appropriately
cached in CustomAttr for serialization.
Introduce availability macros defined by a frontend flag.
This feature makes it possible to set the availability
versions at the moment of compilation instead of having
it hard coded in the sources. It can be used by projects
with a need to change the availability depending on the
compilation context while using the same sources.
The availability macro is defined with the `-define-availability` flag:
swift MyLib.swift -define-availability "_iOS8Aligned:macOS 10.10, iOS 8.0" ..
The macro can be used in code instead of a platform name and version:
@available(_iOS8Aligned, *)
public func foo() {}
rdar://problem/65612624
A stored property can be part of a pattern binding entry whose pattern
declares multiple bindings with a single initializer, for example:
struct S {
let (x, y) = (0, 0)
}
Make sure these round-trip correctly.
