/* Test for NaN that does not need libm. Copyright (C) 2007-2017 Free Software Foundation, Inc. This program is free software: you can redistribute it and/or modify it under the terms of the GNU Lesser 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 Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with this program. If not, see . */ #if HAVE_ISNANF_IN_LIBC /* Get declaration of isnan macro or (older) isnanf function. */ # include # if __GNUC__ >= 4 /* GCC 4.0 and newer provides three built-ins for isnan. */ # undef isnanf # define isnanf(x) __builtin_isnanf ((float)(x)) # elif defined isnan # undef isnanf # define isnanf(x) isnan ((float)(x)) # else /* Get declaration of isnanf(), if not declared in . */ # if defined __sgi /* We can't include , because it conflicts with our definition of isnand. Therefore declare isnanf separately. */ extern int isnanf (float x); # endif # endif #else /* Test whether X is a NaN. */ # undef isnanf # define isnanf rpl_isnanf extern int isnanf (float x); #endif