[PATCH] D34574: [Sema] Disable c++17 aligned new and delete operators if not implemented in the deployment target's c++ standard library

[Duncan P. N. Exon Smith via Phabricator via cfe-commits]

dexonsmith added a comment.

In https://reviews.llvm.org/D34574#791158, @rsmith wrote:

> Should we also remove the recently-added availability attributes in libc++ too? If I'm using a recent libc++ and providing my own aligned allocation functions, we shouldn't reject attempts to call those aligned allocation functions.


Ugh; maybe.  There's `-D_LIBCPP_DISABLE_AVAILABILITY` already, but that's too big a hammer (disables //all// of the markup).


https://reviews.llvm.org/D34574