I didn't try that - if it works, then yes I guess that's an option. It is possible that it will limit portability, since varargs stuff has traditionally been tricky in that regard - but since you're not actually looking at the additional arguments (ie not calling va_start), maybe that won't be a problem.

I've no idea what C that will translate to: I'm curious how it will decide to invoke the typemaps, since you have not declared what type the additional arguments are. In principle that might even make it slightly faster.