1 #include <math.h> 2 #include <float.h> 3 4 #if LDBL_MANT_DIG == 53 && LDBL_MAX_EXP == 1024 5 long double fmaxl(long double x, long double y) 6 { 7 return fmax(x, y); 8 } 9 #else 10 long double fmaxl(long double x, long double y) 11 { 12 if (isnan(x)) 13 return y; 14 if (isnan(y)) 15 return x; 16 /* handle signed zeros, see C99 Annex F.9.9.2 */ 17 if (signbit(x) != signbit(y)) 18 return signbit(x) ? y : x; 19 return x < y ? y : x; 20 } 21 #endif 22