Swift validates the retain/release operations for foreign reference types to check for obvious errors, e.g. a wrong parameter type or return type.
That logic was only running for C++ foreign reference types. This patch enables it for C foreign reference types as well.
rdar://158609723
When we cannot respect the "destroy:" annotation, mark the type as
deprecated with a message thst says why there is a problem. There are
various potential problems:
* Multiple conflicting destroy functions
* Destroy functions that don't meet the pattern
* Type isn't imported as a move-only type
* Type has a non-trivial destructor (in C++)
A C struct can be imported as noncopyable, but C doesn't have
destructors, so there is no way to provide user-defined logic to
perform the destruction. Introduce a new swift_attr that applies to
imported noncopyable types and which provides such a "destroy"
operation. It can be used like this:
typedef struct __attribute__((swift_attr("~Copyable")))
__attribute__((swift_attr("destroy:wgpuAdapterInfoFreeMembers")))
WGPUAdapterInfo { /*...*/ } WGPUAdapterInfo;
void wgpuAdapterInfoFreeMembers(WGPUAdapterInfo adapterInfo);
This will bring the WGPUAdapterInfo struct in as a noncopyable type
that will be cleaned up by calling wgpuAdapterInfoFreeMembers once it
is no longer in use.
Implements rdar://156889370.
The code for handling Swift conforms_to attributes was specific to
C++ record types. Generalize it to work on typedefs imported as
nominal types, also in C.
Fixes rdar://156290361.
Some of the patterns in the new test header are special-cased by
ClangImporter (for example, the names of typedefs become names of
imported structs).
Nested structs have been historically imported in Swift according to C
rules, that is, structs lexically declared nested in other structs are
imported into the global namespace anyway. For the same reason, C
structs have been mangled in Swift names as if they are declared in the
global namespace. These rules are problematic when importing C++, see
https://bugs.swift.org/browse/SR-12803.
