__builtin_addressof was added to the GCC trunk in the past week. This patch
teaches libc++ about it so it can correctly provide constexpr addressof.
Unfortunately this patch will break users of earlier GCC 7 builds, since
we expect __builtin_addressof but one won't be provided. One option would be
to only use __builtin_addressof for GCC 7.1 and above, but that means
waiting for another release.
Instead I've specifically chosen to break older GCC 7 versions. Since GCC 7
has yet to be released, and the 7.0 release is a development release, I
believe that anybody currently using GCC 7.0 will have no issue upgrading.
llvm-svn: 283715
Fixes a small omission in libcxx that prevents libcxx being built when
-DLIBCXX_ENABLE_EXCEPTIONS=0 is specified.
This patch adds XFAILS to all those tests that are currently failing
on the new -fno-exceptions library variant. Follow-up patches will
update the tests (progressively) to cope with the new library variant.
Change-Id: I4b801bd8d8e4fe7193df9e55f39f1f393a8ba81a
llvm-svn: 252598