lit.py currently allows any substring of `target_triple` to be used as a
feature in REQUIRES/UNSUPPORTED/XFAIL. This results in various forms of
the OS spread across the tests and is also somewhat confusing since they
aren't actually listed in the available features.
Modify all OS-related features to use the `OS=` version that Swift adds
instead. We can later remove `config.target_triple` so that these don't
the non-OS versions don't work in the first place.
If we find multiple conformances for the same protocol, we generate a
warning. This works fine for Swift types, but for Objective-C types
it's possible that while generating the warning we might find that the
type description is NULL.
Fix by using swift_getTypeName().
rdar://86368350
Apparently it's necessary to list all the files used in %target-run, otherwise
when we're running the tests remotely on a device, they might not be copied.
rdar://80283113
Added a test that builds two dynamic libraries and sets up a redundant protocol
conformance (we use dynamic libraries because the compiler will normally reject
redundant conformances), then checks that when we rely on it, we get a warning
message.
