Don't warn about -Wno-foo where foo is an unknown warning option. Explicitly
passing -Wunknown-warning-option will re-enable warnings about -Wno-foo.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@132570 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed