[libcxx-commits] [libcxx] [libc++][test] Use `TEST_MEOW_DIAGNOSTIC_IGNORED` instead of `ADDITIONAL_COMPILE_FLAGS` (PR #75133)

[Nikolas Klauser via libcxx-commits]

https://github.com/philnik777 requested changes to this pull request.

I'm not a huge fan of this approach. It results in this weird dance of first including `test_macros.h`, then disabling some warnings and after that include other headers. To be clear, I think it's a good idea to use them in places where we only want to disable warnings for a few lines. That's what they were intended for. But I don't think it's a good idea if we want to disable a warning for the whole file.

https://github.com/llvm/llvm-project/pull/75133