It is intended to disable _all_ warnings, even those upgraded to
errors via `-Werror=warningname` or `#pragma clang diagnostic error'
Fixes: https://llvm.org/PR38231
Differential Revision: https://reviews.llvm.org/D53199
llvm-svn: 352535
- This fixes a host of obscure bugs with regards to how warning mapping options composed with one another, and I believe makes the code substantially easier to read and reason about.
llvm-svn: 140770