And hell, GCC already includes a lot of really really obscure builtin functions which are one hell of a lot less common & useful than multiply-hi&lo. I merely cited div(a,b) because it was one of the least obscure among them. How about freaking "isgraph" and "_mm_set1_epi32"?
I mean how can you justify building them in, but not this? You cannot. And that isn't because I failed to "learn basic principles about language design." -- Warren D. Smith http://RangeVoting.org <-- add your endorsement (by clicking "endorse" as 1st step)