[libcxx-commits] [libcxx] [libcxxabi] [libc++] Provide aligned allocation function iff the compiler claims support (PR #219199)

[Louis Dionne via libcxx-commits]

https://github.com/ldionne approved this pull request.

Revisiting this, it looks like VS 2017 version 15.3 is not supported by Microsoft itself, so I don't think it makes sense to keep supporting it.

However, IIUC this is a behavior change since we will stop declaring `align_val_t` when `-fno-aligned-alloc` is passed (we previously defined it nonetheless). I guess this is acceptable, I can't think of a reason for wanting `align_val_t` but `-fno-aligned-alloc`.

https://github.com/llvm/llvm-project/pull/219199