[libc++] Add hack to allow ubsan to work w/o compiler-rt (__muloti4 is undefined)
Summary:
Using int128_t with UBSAN causes link errors unless compiler-rt is providing the runtime library.
Specifically ubsan generates calls to __muloti4 but libgcc doesn't provide a definition.
In order to avoid this, and allow users to continue using sanitized versions of libc++, this patch introduces a hack.
It adds a cribbed version of the compiler-rt builtin to the libc++ filesystem sources.
I don't think this approach will work in the long run, but it seems OK for now.
Also see:
https://bugs.llvm.org/show_bug.cgi?id=30643
https://bugs.llvm.org/show_bug.cgi?id=16404
Reviewers: mclow.lists, ldionne, rsmith, jyknight, echristo
Reviewed By: echristo
Subscribers: dberris, cfe-commits
Differential Revision: https://reviews.llvm.org/D49828
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@337990 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed