4 int isnan (int x) { return x != x; }
5 int isnan (float x) { return x != x; }
6 int isnan (double x) { return x != x; }
7 int isnan (long double x) { return x != x; }
9 int isinf(int x) { return !isnan (x) && isnan (x - x); }
10 int isinf(float x) { return !isnan (x) && isnan (x - x); }
11 int isinf(double x) { return !isnan (x) && isnan (x - x); }
12 int isinf(long double x) { return !isnan (x) && isnan (x - x); }