[PATCH] D50341: [libcxx] Fix XFAILs for aligned allocation tests on older OSX versions

[Louis Dionne via Phabricator via cfe-commits]

ldionne added a comment.

In https://reviews.llvm.org/D50341#1198339, @vsapsai wrote:

> What about defining a feature for unsupported configurations? I've tried
>
>   if '__cpp_aligned_new' not in macros or \
>           intMacroValue(macros['__cpp_aligned_new']) < 201606:
>       self.config.available_features.add('libcpp-no-aligned-new')
>   
>
> and `// UNSUPPORTED: libcpp-no-aligned-new`. Seems to be working but it's not sufficient. For example, clang-6 for old macOS versions would define `__cpp_aligned_new` but a test would fail. Still, we can use another feature, not necessarily macro-based. Though probably something like `libcpp-no-aligned-new` can replace `// UNSUPPORTED: c++98, c++03, c++11, c++14`.


I thought about something like this, but it would only be useful in a couple of places, and I still don't understand why the tests are marked as unsupported on some compilers at all. Also, there's already a feature called `no-aligned-alloc`, which tests whether `-faligned-alloc` is supported, so we should avoid confusing both.


Repository:
  rCXX libc++

https://reviews.llvm.org/D50341