[PATCH] D50344: [libc++] Enable aligned allocation based on feature test macro, irrespective of standard

[Louis Dionne via Phabricator via cfe-commits]

ldionne marked an inline comment as done.
ldionne added inline comments.


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Comment at: libcxx/test/libcxx/memory/aligned_allocation_macro.pass.cpp:11
+// UNSUPPORTED: c++98, c++03, c++11, c++14
+// XFAIL: with_system_cxx_lib=macosx10.12
+// XFAIL: with_system_cxx_lib=macosx10.11
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vsapsai wrote:
> Initially `with_system_cxx_lib` made me suspicious because macro `_LIBCPP_HAS_NO_ALIGNED_ALLOCATION` doesn't need specific dylib. And `XFAIL: availability=macosx10.12` seems to be working.
> 
> [Documentation](https://github.com/llvm-mirror/libcxx/blob/master/docs/DesignDocs/AvailabilityMarkup.rst#testing) describes which feature should be used in different cases but in this case I cannot definitely say if test uses unavailable feature. I think it is acceptable to stick with `with_system_cxx_lib` but I decided to brought to your attention the alternative.
My understanding is that the `availability` feature may not be there if we're not using availability macros, since they can be disabled entirely.


Repository:
  rCXX libc++

https://reviews.llvm.org/D50344