[libcxx-commits] [libcxx] [libc++] Implement LWG4290: Missing Mandates clauses on is_sufficiently_aligned (PR #229765)

[Nikolas Klauser via libcxx-commits]

https://github.com/philnik777 commented:

> Since this is my first patch, the PR is limited to the static assert check. However, we could now theoretically replace the modulo operator `%` with a bitwise and operator `&` for the alignment check:
> 
> ```
> return (reinterpret_cast<uintptr_t>(__ptr) & (_Alignment - 1)) == 0;
> ```
> 
> Just thought I would raise this for discussion. I am not sure if that makes a difference past `-O0`; whether there's any interest in that; if that would belong in a separate PR.

The compiler does that even at -O0 AFAICT: https://godbolt.org/z/hroonYYfj

https://github.com/llvm/llvm-project/pull/229765