lib/isnanl-nolibm.h

   1 /* Test for NaN that does not need libm.
   2    Copyright (C) 2007-2024 Free Software Foundation, Inc.
   3
   4    This file is free software: you can redistribute it and/or modify
   5    it under the terms of the GNU Lesser General Public License as
   6    published by the Free Software Foundation; either version 2.1 of the
   7    License, or (at your option) any later version.
   8
   9    This file 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 Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public License
  15    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  16
  17 /* This file uses HAVE_ISNANL_IN_LIBC.  */
  18 #if !_GL_CONFIG_H_INCLUDED
  19  #error "Please include config.h first."
  20 #endif
  21
  22 #if HAVE_ISNANL_IN_LIBC
  23 /* Get declaration of isnan macro or (older) isnanl function.  */
  24 # include <math.h>
  25 # if (__GNUC__ >= 4) || (__clang_major__ >= 4)
  26    /* GCC >= 4.0 and clang provide a type-generic built-in for isnan.
  27       GCC >= 4.0 also provides __builtin_isnanl, but clang doesn't.  */
  28 #  undef isnanl
  29 #  define isnanl(x) __builtin_isnan ((long double)(x))
  30 # elif defined isnan
  31 #  undef isnanl
  32 #  define isnanl(x) isnan ((long double)(x))
  33 # endif
  34 #else
  35 /* Test whether X is a NaN.  */
  36 # undef isnanl
  37 # define isnanl rpl_isnanl
  38 extern int isnanl (long double x);
  39 #endif