1 | /* `HUGE_VALF' constant for IEEE 754 machines (where it is infinity). |
2 | Used by <stdlib.h> and <math.h> functions for overflow. |
3 | Copyright (C) 1992-2016 Free Software Foundation, Inc. |
4 | This file is part of the GNU C Library. |
5 | |
6 | The GNU C Library is free software; you can redistribute it and/or |
7 | modify it under the terms of the GNU Lesser General Public |
8 | License as published by the Free Software Foundation; either |
9 | version 2.1 of the License, or (at your option) any later version. |
10 | |
11 | The GNU C Library is distributed in the hope that it will be useful, |
12 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
14 | Lesser General Public License for more details. |
15 | |
16 | You should have received a copy of the GNU Lesser General Public |
17 | License along with the GNU C Library; if not, see |
18 | <http://www.gnu.org/licenses/>. */ |
19 | |
20 | #ifndef _MATH_H |
21 | # error "Never use <bits/huge_valf.h> directly; include <math.h> instead." |
22 | #endif |
23 | |
24 | /* IEEE positive infinity (-HUGE_VAL is negative infinity). */ |
25 | |
26 | #if __GNUC_PREREQ(3,3) |
27 | # define HUGE_VALF (__builtin_huge_valf()) |
28 | #elif __GNUC_PREREQ(2,96) |
29 | # define HUGE_VALF (__extension__ 0x1.0p255f) |
30 | #elif defined __GNUC__ |
31 | |
32 | # define HUGE_VALF \ |
33 | (__extension__ \ |
34 | ((union { unsigned __l __attribute__((__mode__(__SI__))); float __d; }) \ |
35 | { __l: 0x7f800000UL }).__d) |
36 | |
37 | #else /* not GCC */ |
38 | |
39 | typedef union { unsigned char __c[4]; float __f; } __huge_valf_t; |
40 | |
41 | # if __BYTE_ORDER == __BIG_ENDIAN |
42 | # define __HUGE_VALF_bytes { 0x7f, 0x80, 0, 0 } |
43 | # endif |
44 | # if __BYTE_ORDER == __LITTLE_ENDIAN |
45 | # define __HUGE_VALF_bytes { 0, 0, 0x80, 0x7f } |
46 | # endif |
47 | |
48 | static __huge_valf_t __huge_valf = { __HUGE_VALF_bytes }; |
49 | # define HUGE_VALF (__huge_valf.__f) |
50 | |
51 | #endif /* GCC. */ |
52 | |