/* Test for NaN that does not need libm. Copyright (C) 2007-2012 Free Software Foundation, Inc. This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see <http://www.gnu.org/licenses/>. */ #if HAVE_ISNAND_IN_LIBC /* Get declaration of isnan macro. */ # include <math.h> # if __GNUC__ >= 4 /* GCC 4.0 and newer provides three built-ins for isnan. */ # undef isnand # define isnand(x) __builtin_isnan ((double)(x)) # else # undef isnand # define isnand(x) isnan ((double)(x)) # endif #else /* Test whether X is a NaN. */ # undef isnand # define isnand rpl_isnand extern int isnand (double x); #endif