Defensive GCC flag: don't fail for unknown warnings (only one of either GCC or Clang has -Wunused-but-set-variable
Defensive GCC flag: don't fail for unknown warnings (only one of either GCC or Clang has -Wunused-but-set-variable

FStarLang/kremlin,FStarLang/kremlin,FStarLang/kremlin,FStarLang/kremlin