Edit: /usr/include/bits/huge_valf.h (1901B)
/* `HUGE_VALF' constant for IEEE 754 machines (where it is infinity).
Used by
and functions for overflow.
Copyright (C) 1992, 1995, 1996, 1997, 1999, 2000, 2004
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 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.
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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; 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 directly; include instead."
#endif
/* IEEE positive infinity (-HUGE_VAL is negative infinity). */
#if __GNUC_PREREQ(3,3)
# define HUGE_VALF (__builtin_huge_valf())
#elif __GNUC_PREREQ(2,96)
# define HUGE_VALF (__extension__ 0x1.0p255f)
#elif defined __GNUC__
# define HUGE_VALF \
(__extension__ \
((union { unsigned __l __attribute__((__mode__(__SI__))); float __d; }) \
{ __l: 0x7f800000UL }).__d)
#else /* not GCC */
typedef union { unsigned char __c[4]; float __f; } __huge_valf_t;
# if __BYTE_ORDER == __BIG_ENDIAN
# define __HUGE_VALF_bytes { 0x7f, 0x80, 0, 0 }
# endif
# if __BYTE_ORDER == __LITTLE_ENDIAN
# define __HUGE_VALF_bytes { 0, 0, 0x80, 0x7f }
# endif
static __huge_valf_t __huge_valf = { __HUGE_VALF_bytes };
# define HUGE_VALF (__huge_valf.__f)
#endif /* GCC. */