------- Additional Comments From ebotcazou at gcc dot gnu dot org 2005-05-03
09:48 -------
> I'm not sure what is best done with the signbit definition (maybe nothing if
> it will never call a library function at present, even though it isn't
> properly type-generic);
We can discriminate using sizeof, like in glibc.
> but the others can be done, e.g.
>
> #define isfinite(x) __extension__ ({ __typeof (x) __x = (x); __builtin_expect
(!isnan(__x - __x), 1); })
This works fine for "big" numbers, but are there similar tricks to distinguish
denormals from normals? If no, we'll have to resort to FLT_MIN and the like or
to bitwise-testing the exponent against 0.
I'm going to attach a first version of math_c99.h.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19933
