1/* `HUGE_VAL' constants for ix86 (where it is infinity). 2 Used by <stdlib.h> and <math.h> functions for overflow. 3 Copyright (C) 1992, 1995, 1996, 1997, 1999, 2000 Free Software Foundation, Inc. 4 This file is part of the GNU C Library. 5 6 The GNU C Library is free software; you can redistribute it and/or 7 modify it under the terms of the GNU Lesser General Public 8 License as published by the Free Software Foundation; either 9 version 2.1 of the License, or (at your option) any later version. 10 11 The GNU C Library is distributed in the hope that it will be useful, 12 but WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 14 Lesser General Public License for more details. 15 16 You should have received a copy of the GNU Lesser General Public 17 License along with the GNU C Library; if not, write to the Free 18 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 19 02111-1307 USA. */ 20 21#ifndef _MATH_H 22# error "Never use <bits/huge_val.h> directly; include <math.h> instead." 23#endif 24 25#include <features.h> 26 27/* IEEE positive infinity (-HUGE_VAL is negative infinity). */ 28 29#if __GNUC_PREREQ(2,96) 30# define HUGE_VAL (__extension__ 0x1.0p2047) 31#else 32# define __HUGE_VAL_bytes { 0, 0, 0, 0, 0, 0, 0xf0, 0x7f } 33 34# define __huge_val_t union { unsigned char __c[8]; double __d; } 35# ifdef __GNUC__ 36# define HUGE_VAL (__extension__ \ 37 ((__huge_val_t) { __c: __HUGE_VAL_bytes }).__d) 38# else /* Not GCC. */ 39static __huge_val_t __huge_val = { __HUGE_VAL_bytes }; 40# define HUGE_VAL (__huge_val.__d) 41# endif /* GCC. */ 42#endif /* GCC 2.95 */ 43 44 45/* ISO C99 extensions: (float) HUGE_VALF and (long double) HUGE_VALL. */ 46 47#ifdef __USE_ISOC99 48 49# if __GNUC_PREREQ(2,96) 50 51# define HUGE_VALF (__extension__ 0x1.0p255f) 52# define HUGE_VALL (__extension__ 0x1.0p32767L) 53 54# else 55 56# define __HUGE_VALF_bytes { 0, 0, 0x80, 0x7f } 57 58# define __huge_valf_t union { unsigned char __c[4]; float __f; } 59# ifdef __GNUC__ 60# define HUGE_VALF (__extension__ \ 61 ((__huge_valf_t) { __c: __HUGE_VALF_bytes }).__f) 62# else /* Not GCC. */ 63static __huge_valf_t __huge_valf = { __HUGE_VALF_bytes }; 64# define HUGE_VALF (__huge_valf.__f) 65# endif /* GCC. */ 66 67 68# define __HUGE_VALL_bytes { 0, 0, 0, 0, 0, 0, 0, 0x80, 0xff, 0x7f, 0, 0 } 69 70# define __huge_vall_t union { unsigned char __c[12]; long double __ld; } 71# ifdef __GNUC__ 72# define HUGE_VALL (__extension__ \ 73 ((__huge_vall_t) { __c: __HUGE_VALL_bytes }).__ld) 74# else /* Not GCC. */ 75static __huge_vall_t __huge_vall = { __HUGE_VALL_bytes }; 76# define HUGE_VALL (__huge_vall.__ld) 77# endif /* GCC. */ 78 79# endif /* GCC 2.95 */ 80 81#endif /* __USE_ISOC99. */ 82