[OT] __builtin_cpow((0,0),(0,0))

[Paolo Carlini]

Duncan Sands wrote:

>aren't __builtin_cpow and friends language independent?  I mean, if a
>front-end sees a x^y then presumably it ends up being turned into a
>call to a __builtin_?pow by the back-end.  If so, then conforming to
>the C99 and C++ standards isn't enough: the standards for all gcc
>supported languages need to be checked.
>
This is a good question, indeed. I don't think Ada, for instance, is using
__builtin_cpow internally, or cpow, for that matter, since many widespread
libc implementations have cpow(0,0) returning (nan, nan) contra the Ada
RM, as mentioned by Robert Dewar.

Paolo.