http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60732
mrs at gcc dot gnu.org <mrs at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |mrs at gcc dot gnu.org --- Comment #1 from mrs at gcc dot gnu.org <mrs at gcc dot gnu.org> --- The flag is documented to default to 2. Darwin does nothing special here (that I could find or remember). One simply cannot change mangling without checking this flag. If the flag doesn't change, then how can the mangling change? If one wants to check a new mangling, then they have to use -fabi-version=n, where is the the version they want to check. I don't see why that would be dependent upon darwin; it should be unconditional. Confused.