PrintAsClang is supposed to emit declarations in the same order regardless of the compiler’s internal state, but we have repeatedly found that our current criteria are inadequate, resulting in non-functionality-affecting changes to generated header content. Add a diagnostic that’s emitted when this happens soliciting a bug report.
Since there *should* be no cases where the compiler fails to order declarations, this diagnostic is never actually emitted. Instead, we test this change by enabling `-verify` on nearly all PrintAsClang tests to make sure they are unaffected.
This did demonstrate a missing criterion that only mattered in C++ mode: extensions that varied only in their generic signature were not sorted stably. Add a sort criterion for this.
Find all the usages of `--enable-experimental-feature` or
`--enable-upcoming-feature` in the tests and replace some of the
`REQUIRES: asserts` to use `REQUIRES: swift-feature-Foo` instead, which
should correctly apply to depending on the asserts/noasserts mode of the
toolchain for each feature.
Remove some comments that talked about enabling asserts since they don't
apply anymore (but I might had miss some).
All this was done with an automated script, so some formatting weirdness
might happen, but I hope I fixed most of those.
There might be some tests that were `REQUIRES: asserts` that might run
in `noasserts` toolchains now. This will normally be because their
feature went from experimental to upcoming/base and the tests were not
updated.
10.50 was once greater than any real macOS version, but now it compares
less than real released versions, which makes these tests depend on the
deployment target unnecessarily. Update these tests to use even larger
numbers to hopefully keep them independent a little longer.
• ObjCImplementation controls @implementation on extensions
• CImplementation controls @implementation and @_objcImplementation on cdecl functions
Why the difference between them? Because `@_objcImplementation extension` has already been adopted pretty widely, while `@_objcImplementation @_cdecl` is very new.
Previously we only excluded implicitly-created overrides, but it turns out explicit overrides are just as problematic and just as unnecessary.
Fixes rdar://123633538.
PrintAsClang was not aware of @objcImplementation. Teach it to skip over both member implementations (which are declared in handwritten headers, so printing them would be a redeclaration) and overrides (which may not be valid in a category, if e.g. they are declaring a designated initializer).
Fixes rdar://106035578.
