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- /* `HUGE_VAL' constants 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 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
- #include <features.h>
- /* IEEE positive infinity (-HUGE_VAL is negative infinity). */
- #ifdef __GNUC__
- # if __GNUC_PREREQ(2,96)
- # define HUGE_VAL (__extension__ 0x1.0p2047)
- # else
- # define HUGE_VAL \
- (__extension__ \
- ((union { unsigned __l __attribute__((__mode__(__DI__))); double __d; }) \
- { __l: 0x7ff0000000000000ULL }).__d)
- # endif
- #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. */
- /* ISO C99 extensions: (float) HUGE_VALF and (long double) HUGE_VALL. */
- #ifdef __USE_ISOC99
- # ifdef __GNUC__
- # if __GNUC_PREREQ(2,96)
- # define HUGE_VALF (__extension__ 0x1.0p255f)
- # else
- # define HUGE_VALF \
- (__extension__ \
- ((union { unsigned __l __attribute__((__mode__(__SI__))); float __d; }) \
- { __l: 0x7f800000UL }).__d)
- # endif
- # 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. */
- /* Generally there is no separate `long double' format and it is the
- same as `double'. */
- # define HUGE_VALL HUGE_VAL
- #endif /* __USE_ISOC99. */
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