| /* Test for NaN that does not need libm. |
| Copyright (C) 2007-2019 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 2.1 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 <https://www.gnu.org/licenses/>. */ |
| |
| #if HAVE_ISNAND_IN_LIBC |
| /* Get declaration of isnan macro. */ |
| # include <gnulib_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 |
