Ahh, gosh I'm slow today. The math libraries include bits/mathinline.h
instead of using the linked in library if optimisations are turned on. It
wont do this if you have __STRICT_ANSI__ defined or __NO_MATH_INLINES ...
so the simple answer to the problem is to do --ansi as a compile option,
though that may hit other things and remove our optimisations. So perhaps
it might be better to use the no_math_inlines approach. Either that, or
we can check ourselves and call void __sincos(double argument, double
*sinAnswer, double *cosAnswer);

Michael.