lib/libc/ack/math/isnan.c

   1 int __IsNan(double d)
   2 {
   3 #if defined(vax) || defined(pdp)
   4 #else
   5         float f = d;
   6
   7         if ((*((long *) &f) & 0x7f800000) == 0x7f800000 &&
   8             (*((long *) &f) & 0x007fffff) != 0) return 1;
   9 #endif
  10         return 0;
  11 }