[libcxx-commits] [libcxx] [libc++] Remove explicit mentions of __need_FOO macros (PR #119025)

[Petr Hosek via libcxx-commits]

petrhosek wrote:

The behavior of system `wchar.h` differs based on which `__need_FOO` macros; this is the case for other system headers as well, not just `wchar.h`, so the fact that it's being included multiple times is likely working as intended in this case.

@ldionne Would it be possible to revert this change? I plan to continue looking into this issue to see if there's another way to achieve the same result without breaking the compatibility with older sysroots, but I'd like to avoid leaving our downstream builders completely broken for the next two weeks since that will mean will loose test coverage during that time.

https://github.com/llvm/llvm-project/pull/119025