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/* `NAN' constant for IEEE 754 machines.
Copyright (C) 1992, 1996, 1997 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
The GNU C Library 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#ifndef _MATH_H
# error "Never use <bits/nan.h> directly; include <math.h> instead."
#endif
/* IEEE Not A Number. */
#ifdef __GNUC__
# define NAN \
(__extension__ \
((union { unsigned __l __attribute__((__mode__(__SI__))); float __d; }) \
{ __l: 0x7fc00000UL }).__d)
#else
# include <endian.h>
# if __BYTE_ORDER == __BIG_ENDIAN
# define __nan_bytes { 0x7f, 0xc0, 0, 0 }
# endif
# if __BYTE_ORDER == __LITTLE_ENDIAN
# define __nan_bytes { 0, 0, 0xc0, 0x7f }
# endif
static union { unsigned char __c[4]; float __d; } __nan = { __nan_bytes };
# define NAN (__nan.__d)
#endif /* GCC. */
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