[llvm-branch-commits] [clang] release/18.x: [Headers] Don't declare unreachable() from stddef.h in C++ (#86748) (PR #87696)

[Ian Anderson via llvm-branch-commits]

ian-twilightcoder wrote:

I don't think we need to release note this one, it's just restoring LLVM 17 behavior.

https://github.com/llvm/llvm-project/pull/87696