aboutsummaryrefslogtreecommitdiffstats
path: root/libavutil/attributes.h
blob: 4abe78f3bfb3e4bab2b0e0d44c80154f11f30044 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
/*
 * copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
 *
 * This file is part of Libav.
 *
 * Libav 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.
 *
 * Libav 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 Libav; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

/**
 * @file
 * Macro definitions for various function/variable attributes
 */

#ifndef AVUTIL_ATTRIBUTES_H
#define AVUTIL_ATTRIBUTES_H

#ifdef __GNUC__
#    define AV_GCC_VERSION_AT_LEAST(x,y) (__GNUC__ > x || __GNUC__ == x && __GNUC_MINOR__ >= y)
#else
#    define AV_GCC_VERSION_AT_LEAST(x,y) 0
#endif

#ifndef av_always_inline
#if AV_GCC_VERSION_AT_LEAST(3,1)
#    define av_always_inline __attribute__((always_inline)) inline
#else
#    define av_always_inline inline
#endif
#endif

#ifndef av_noinline
#if AV_GCC_VERSION_AT_LEAST(3,1)
#    define av_noinline __attribute__((noinline))
#else
#    define av_noinline
#endif
#endif

#ifndef av_pure
#if AV_GCC_VERSION_AT_LEAST(3,1)
#    define av_pure __attribute__((pure))
#else
#    define av_pure
#endif
#endif

#ifndef av_const
#if AV_GCC_VERSION_AT_LEAST(2,6)
#    define av_const __attribute__((const))
#else
#    define av_const
#endif
#endif

#ifndef av_cold
#if AV_GCC_VERSION_AT_LEAST(4,3)
#    define av_cold __attribute__((cold))
#else
#    define av_cold
#endif
#endif

#ifndef av_flatten
#if AV_GCC_VERSION_AT_LEAST(4,1)
#    define av_flatten __attribute__((flatten))
#else
#    define av_flatten
#endif
#endif

#ifndef attribute_deprecated
#if AV_GCC_VERSION_AT_LEAST(3,1)
#    define attribute_deprecated __attribute__((deprecated))
#else
#    define attribute_deprecated
#endif
#endif

#ifndef av_unused
#if defined(__GNUC__)
#    define av_unused __attribute__((unused))
#else
#    define av_unused
#endif
#endif

/**
 * Mark a variable as used and prevent the compiler from optimizing it
 * away.  This is useful for variables accessed only from inline
 * assembler without the compiler being aware.
 */
#ifndef av_used
#if AV_GCC_VERSION_AT_LEAST(3,1)
#    define av_used __attribute__((used))
#else
#    define av_used
#endif
#endif

#ifndef av_alias
#if AV_GCC_VERSION_AT_LEAST(3,3)
#   define av_alias __attribute__((may_alias))
#else
#   define av_alias
#endif
#endif

#ifndef av_uninit
#if defined(__GNUC__) && !defined(__ICC)
#    define av_uninit(x) x=x
#else
#    define av_uninit(x) x
#endif
#endif

#ifdef __GNUC__
#    define av_builtin_constant_p __builtin_constant_p
#else
#    define av_builtin_constant_p(x) 0
#endif

#endif /* AVUTIL_ATTRIBUTES_H */