1 /* Test for NaN that does not need libm. 2 Copyright (C) 2007-2012 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 <http://www.gnu.org/licenses/>. */ 16 17 #if HAVE_ISNAND_IN_LIBC 18 /* Get declaration of isnan macro. */ 19 # include <math.h> 20 # if __GNUC__ >= 4 21 /* GCC 4.0 and newer provides three built-ins for isnan. */ 22 # undef isnand 23 # define isnand(x) __builtin_isnan ((double)(x)) 24 # else 25 # undef isnand 26 # define isnand(x) isnan ((double)(x)) 27 # endif 28 #else 29 /* Test whether X is a NaN. */ 30 # undef isnand 31 # define isnand rpl_isnand 32 extern int isnand (double x); 33 #endif 34