1 /* Test for NaN that does not need libm. 2 Copyright (C) 2007-2020 Free Software Foundation, Inc. 3 4 This program is free software: you can redistribute it and/or modify 5 it under the terms of the GNU General Public License as published by 6 the Free Software Foundation; either version 3 of the License, or 7 (at your option) any later version. 8 9 This program is distributed in the hope that it will be useful, 10 but WITHOUT ANY WARRANTY; without even the implied warranty of 11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 GNU General Public License for more details. 13 14 You should have received a copy of the GNU General Public License 15 along with this program. If not, see <https://www.gnu.org/licenses/>. */ 16 17 #if HAVE_ISNANL_IN_LIBC 18 /* Get declaration of isnan macro or (older) isnanl function. */ 19 # include <math.h> 20 # ifndef __has_builtin 21 # define __has_builtin(name) 0 22 # endif 23 # if __GNUC__ >= 4 && (!defined __clang__ || __has_builtin (__builtin_isnanl)) 24 /* GCC 4.0 and newer provides three built-ins for isnan. */ 25 # undef isnanl 26 # define isnanl(x) __builtin_isnanl ((long double)(x)) 27 # elif defined isnan 28 # undef isnanl 29 # define isnanl(x) isnan ((long double)(x)) 30 # endif 31 #else 32 /* Test whether X is a NaN. */ 33 # undef isnanl 34 # define isnanl rpl_isnanl 35 extern int isnanl (long double x); 36 #endif 37