| /* `HUGE_VAL' constant for IEEE 754 machines (where it is infinity). |
| Used by <stdlib.h> and <math.h> 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 <bits/huge_val.h> directly; include <math.h> instead." |
| #endif |
| |
| /* IEEE positive infinity (-HUGE_VAL is negative infinity). */ |
| |
| #if __GNUC_PREREQ(3,3) |
| # define HUGE_VAL (__builtin_huge_val()) |
| #elif __GNUC_PREREQ(2,96) |
| # define HUGE_VAL (__extension__ 0x1.0p2047) |
| #elif defined __GNUC__ |
| |
| # define HUGE_VAL \ |
| (__extension__ \ |
| ((union { unsigned __l __attribute__((__mode__(__DI__))); double __d; }) \ |
| { __l: 0x7ff0000000000000ULL }).__d) |
| |
| #else /* not GCC */ |
| |
| # include <endian.h> |
| |
| typedef union { unsigned char __c[8]; double __d; } __huge_val_t; |
| |
| # if __BYTE_ORDER == __BIG_ENDIAN |
| # define __HUGE_VAL_bytes { 0x7f, 0xf0, 0, 0, 0, 0, 0, 0 } |
| # endif |
| # if __BYTE_ORDER == __LITTLE_ENDIAN |
| # define __HUGE_VAL_bytes { 0, 0, 0, 0, 0, 0, 0xf0, 0x7f } |
| # endif |
| |
| static __huge_val_t __huge_val = { __HUGE_VAL_bytes }; |
| # define HUGE_VAL (__huge_val.__d) |
| |
| #endif /* GCC. */ |