1 /* Test for NaN that does not need libm. 2 Copyright (C) 2007-2021 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 # if (__GNUC__ >= 4) || (__clang_major__ >= 4) 21 /* GCC >= 4.0 and clang provide a type-generic built-in for isnan. 22 GCC >= 4.0 also provides __builtin_isnanl, but clang doesn't. */ 23 # undef isnanl 24 # define isnanl(x) __builtin_isnan ((long double)(x)) 25 # elif defined isnan 26 # undef isnanl 27 # define isnanl(x) isnan ((long double)(x)) 28 # endif 29 #else 30 /* Test whether X is a NaN. */ 31 # undef isnanl 32 # define isnanl rpl_isnanl 33 extern int isnanl (long double x); 34 #endif 35