xfreopen need not depend on freopen-safer
[gnulib.git] / lib / isnanf-nolibm.h
blob73937a2c341a6aefe33ef7f69a4f77e84ff20d46
1 /* Test for NaN that does not need libm.
2 Copyright (C) 2007-2019 Free Software Foundation, Inc.
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.
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.
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/>. */
17 #if HAVE_ISNANF_IN_LIBC
18 /* Get declaration of isnan macro or (older) isnanf function. */
19 # include <math.h>
20 # if __GNUC__ >= 4
21 /* GCC 4.0 and newer provides three built-ins for isnan. */
22 # undef isnanf
23 # define isnanf(x) __builtin_isnanf ((float)(x))
24 # elif defined isnan
25 # undef isnanf
26 # define isnanf(x) isnan ((float)(x))
27 # else
28 /* Get declaration of isnanf(), if not declared in <math.h>. */
29 # if defined __sgi
30 /* We can't include <ieeefp.h>, because it conflicts with our definition of
31 isnand. Therefore declare isnanf separately. */
32 extern int isnanf (float x);
33 # endif
34 # endif
35 #else
36 /* Test whether X is a NaN. */
37 # undef isnanf
38 # define isnanf rpl_isnanf
39 extern int isnanf (float x);
40 #endif