[PATCH] D46056: Move _LIBCPP_ENABLE_CXX17_REMOVED_UNEXPECTED_FUNCTIONS macro to build system

[Taiju Tsuiki via Phabricator via cfe-commits]

tzik added a comment.

rsmith: Could you PTAL to this? This is an attempt to resolve https://bugs.llvm.org/show_bug.cgi?id=34103.
Though we already have a way to bring back std::unexpected to libc++abi, we currently don't apply it properly, IMO.


Repository:
  rCXXA libc++abi

https://reviews.llvm.org/D46056