lib/isnanf-nolibm.h

   1 /* Test for NaN that does not need libm.
   2    Copyright (C) 2007-2020 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 <https://www.gnu.org/licenses/>.  */
  16
  17 #if HAVE_ISNANF_IN_LIBC
  18 /* Get declaration of isnan macro or (older) isnanf function.  */
  19 # include <math.h>
  20 # ifndef __has_builtin
  21 #  define __has_builtin(name) 0
  22 # endif
  23 # if __GNUC__ >= 4 && (!defined __clang__ || __has_builtin (__builtin_isnanf))
  24    /* GCC 4.0 and newer provides three built-ins for isnan.  */
  25 #  undef isnanf
  26 #  define isnanf(x) __builtin_isnanf ((float)(x))
  27 # elif defined isnan
  28 #  undef isnanf
  29 #  define isnanf(x) isnan ((float)(x))
  30 # else
  31    /* Get declaration of isnanf(), if not declared in <math.h>.  */
  32 #  if defined __sgi
  33    /* We can't include <ieeefp.h>, because it conflicts with our definition of
  34       isnand.  Therefore declare isnanf separately.  */
  35 extern int isnanf (float x);
  36 #  endif
  37 # endif
  38 #else
  39 /* Test whether X is a NaN.  */
  40 # undef isnanf
  41 # define isnanf rpl_isnanf
  42 extern int isnanf (float x);
  43 #endif