glibc/sysdeps/i386/huge_val.h

71 lines
2.4 KiB
C

/* `HUGE_VAL' constants for ix86 (where it is infinity).
Used by <stdlib.h> and <math.h> functions for overflow.
Copyright (C) 1992, 1995, 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 _HUGE_VAL_H
#define _HUGE_VAL_H 1
#include <features.h>
#include <sys/cdefs.h>
/* IEEE positive infinity (-HUGE_VAL is negative infinity). */
#define __HUGE_VAL_bytes { 0, 0, 0, 0, 0, 0, 0xf0, 0x7f }
#define __huge_val_t union { unsigned char __c[8]; double __d; }
#ifdef __GNUC__
#define HUGE_VAL (__extension__ \
((__huge_val_t) { __c: __HUGE_VAL_bytes }).__d)
#else /* Not GCC. */
static __huge_val_t __huge_val = { __HUGE_VAL_bytes };
#define HUGE_VAL (__huge_val.__d)
#endif /* GCC. */
/* ISO C 9X extensions: (float) HUGE_VALF and (long double) HUGE_VALL. */
#ifdef __USE_ISOC9X
#define __HUGE_VALF_bytes { 0, 0, 0x80, 0x7f }
#define __huge_valf_t union { unsigned char __c[4]; float __f; }
#ifdef __GNUC__
#define HUGE_VALF (__extension__ \
((__huge_valf_t) { __c: __HUGE_VALF_bytes }).__f)
#else /* Not GCC. */
static __huge_valf_t __huge_valf = { __HUGE_VALF_bytes };
#define HUGE_VALF (__huge_valf.__f)
#endif /* GCC. */
#define __HUGE_VALL_bytes { 0, 0, 0, 0, 0, 0, 0, 0x80, 0xff, 0x7f, 0, 0 }
#define __huge_vall_t union { unsigned char __c[12]; long double __ld; }
#ifdef __GNUC__
#define HUGE_VALL (__extension__ \
((__huge_vall_t) { __c: __HUGE_VALL_bytes }).__ld)
#else /* Not GCC. */
static __huge_vall_t __huge_vall = { __HUGE_VALL_bytes };
#define HUGE_VALL (__huge_vall.__ld)
#endif /* GCC. */
#endif /* __USE_ISOC9X. */
#endif /* huge_val.h */