1 /* `HUGE_VALL' constant 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, 2004 4 Free Software Foundation, Inc. 5 This file is part of the GNU C Library. 6 7 The GNU C Library is free software; you can redistribute it and/or 8 modify it under the terms of the GNU Lesser General Public 9 License as published by the Free Software Foundation; either 10 version 2.1 of the License, or (at your option) any later version. 11 12 The GNU C Library is distributed in the hope that it will be useful, 13 but WITHOUT ANY WARRANTY; without even the implied warranty of 14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15 Lesser General Public License for more details. 16 17 You should have received a copy of the GNU Lesser General Public 18 License along with the GNU C Library; if not, write to the Free 19 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 20 02111-1307 USA. */ 21 22 #ifndef _MATH_H 23 # error "Never use <bits/huge_vall.h> directly; include <math.h> instead." 24 #endif 25 26 #if __GNUC_PREREQ(3,3) 27 # define HUGE_VALL (__builtin_huge_vall()) 28 #elif __GNUC_PREREQ(2,96) 29 # define HUGE_VALL (__extension__ 0x1.0p32767L) 30 #else 31 32 # define __HUGE_VALL_bytes { 0, 0, 0, 0, 0, 0, 0, 0x80, 0xff, 0x7f, 0, 0 } 33 34 # define __huge_vall_t union { unsigned char __c[12]; long double __ld; } 35 # ifdef __GNUC__ 36 # define HUGE_VALL (__extension__ \ 37 ((__huge_vall_t) { __c: __HUGE_VALL_bytes }).__ld) 38 # else /* Not GCC. */ 39 static __huge_vall_t __huge_vall = { __HUGE_VALL_bytes }; 40 # define HUGE_VALL (__huge_vall.__ld) 41 # endif /* GCC. */ 42 43 #endif /* GCC 2.95 */ 44