[libcxx-commits] [libcxx] [libc++] add commonly used aliases in <__config> and remove <cstddef> includes (PR #70598)

[Louis Dionne via libcxx-commits]

ldionne wrote:

We just spoke about this some more and I explained that another aspect I am not comfortable with here is that `size_t` & friends are defined in `stddef.h` and are intended by the standard to be provided by that header, not by other random headers e.g. `<version>`. This would change that.

https://github.com/llvm/llvm-project/pull/70598