[llvm-branch-commits] [libcxx] release/18.x: [libc++] Simplify the implementation of <stddef.h> (#86843) (PR #87374)

[Ian Anderson via llvm-branch-commits]

ian-twilightcoder wrote:

@tstellar what do you think? I'm a little nervous someone else will run into mysterious errors where `rsize_t` isn't declared in C++ mode, and if they aren't intimately familiar with the workings of the clang header they're going to be very confused for a very long time. But on the other hand no one else has run into that yet as far as we know, and stddef.h _is_ particularly touchy. I would err on the side of taking this, at it effectively fixes a C++ regression caused by https://reviews.llvm.org/D157757

https://github.com/llvm/llvm-project/pull/87374