https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94649
--- Comment #9 from Florian Weimer <fw at gcc dot gnu.org> --- (In reply to Richard Biener from comment #1) > It's also an ABI issue when code compiled with -mcx16 and without -mcx16 has > to inter-operate. So it might be a deliberate choice and not a missed > optimization. Is this still an issue today? I thought libatomic would use CMPXCHG16B if the current CPU supports it.
