/* `HUGE_VAL' constants for IEEE 754 machines (where it is infinity). Used by and 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 directly; include instead." #endif #include /* 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 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. */