https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87744
--- Comment #6 from Jonathan Wakely <redi at gcc dot gnu.org> --- (In reply to Jakub Jelinek from comment #4) > Why not just > __l._M_hi += __builtin_uaddll_overflow(__l._M_lo, __c, > &__l._M_lo); > and similarly for subtraction? No good reason - I'll change it. > Is the reason for using the clang compat builtins instead of > __builtin_{add,sub,mul}_overflow the compatibility with clang versions which > don't > support these? Again, no reason, I was just using the ones specific to the type because all the types are fixed. Thanks for the suggestions.