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- /* `HUGE_VALL' 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.
- 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, see
- <http://www.gnu.org/licenses/>. */
- #ifndef _MATH_H
- # error "Never use <bits/huge_vall.h> directly; include <math.h> instead."
- #endif
- #if __GNUC_PREREQ(3,3)
- # define HUGE_VALL (__builtin_huge_vall())
- #else
- # include <bits/wordsize.h>
- # if __WORDSIZE == 32
- # define HUGE_VALL ((long double) HUGE_VAL)
- # elif __GNUC_PREREQ(2,96)
- # define HUGE_VALL (__extension__ 0x1.0p32767L)
- # elif defined __GNUC__
- # define HUGE_VALL \
- (__extension__ \
- ((union { struct { unsigned long __h, __l; } __i; long double __d; }) \
- { __i: { __h: 0x7fff000000000000UL, __l: 0 } }).__d)
- # else /* not GCC */
- typedef union { unsigned char __c[16]; long double __d; } __huge_vall_t;
- # define __HUGE_VALL_bytes { 0x7f, 0xff, 0,0,0,0,0,0,0,0,0,0,0,0,0,0 }
- static __huge_vall_t __huge_vall = { __HUGE_VALL_bytes };
- # define HUGE_VALL (__huge_vall.__d)
- # endif /* GCC. */
- #endif /* GCC 3.3. */
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