Carry flag emulation may be "possibly inefficient" on architectures without carry flag, but not exposing carry flag on architectures with carry flag is definite

Carry flag emulation may be "possibly inefficient" on architectures without carry flag, but not exposing carry flag on architectures with carry flag is definitely inefficient. I don't think it is the right tradeoff. Consider that many architectures on which C can be used lack hardware multipliers. This is totally not an argument against having multiplication in the language.