MPD  0.20.15
Compiler.h
Go to the documentation of this file.
1 /*
2  * Copyright 2003-2017 The Music Player Daemon Project
3  * http://www.musicpd.org
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License as published by
7  * the Free Software Foundation; either version 2 of the License, or
8  * (at your option) any later version.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License along
16  * with this program; if not, write to the Free Software Foundation, Inc.,
17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
18  */
19 
20 #ifndef COMPILER_H
21 #define COMPILER_H
22 
23 #define GCC_MAKE_VERSION(major, minor, patchlevel) ((major) * 10000 + (minor) * 100 + patchlevel)
24 
25 #ifdef __GNUC__
26 #define GCC_VERSION GCC_MAKE_VERSION(__GNUC__, __GNUC_MINOR__, __GNUC_PATCHLEVEL__)
27 #else
28 #define GCC_VERSION 0
29 #endif
30 
31 #ifdef __clang__
32 # define CLANG_VERSION GCC_MAKE_VERSION(__clang_major__, __clang_minor__, __clang_patchlevel__)
33 #elif defined(__GNUC__)
34 # define CLANG_VERSION 0
35 #endif
36 
41 #define GCC_CHECK_VERSION(major, minor) \
42  (CLANG_VERSION == 0 && \
43  GCC_VERSION >= GCC_MAKE_VERSION(major, minor, 0))
44 
49 #define CLANG_OR_GCC_VERSION(major, minor) \
50  (CLANG_VERSION > 0 || GCC_CHECK_VERSION(major, minor))
51 
56 #define GCC_OLDER_THAN(major, minor) \
57  (GCC_VERSION > 0 && CLANG_VERSION == 0 && \
58  GCC_VERSION < GCC_MAKE_VERSION(major, minor, 0))
59 
60 #ifdef __clang__
61 # if __clang_major__ < 3
62 # error Sorry, your clang version is too old. You need at least version 3.1.
63 # endif
64 #elif defined(__GNUC__)
65 # if GCC_OLDER_THAN(4,9)
66 # error Sorry, your gcc version is too old. You need at least version 4.9.
67 # endif
68 #else
69 # warning Untested compiler. Use at your own risk!
70 #endif
71 
75 #define CLANG_CHECK_VERSION(major, minor) \
76  (CLANG_VERSION >= GCC_MAKE_VERSION(major, minor, 0))
77 
78 #if CLANG_OR_GCC_VERSION(4,0)
79 
80 /* GCC 4.x */
81 
82 #define gcc_const __attribute__((const))
83 #define gcc_deprecated __attribute__((deprecated))
84 #define gcc_may_alias __attribute__((may_alias))
85 #define gcc_malloc __attribute__((malloc))
86 #define gcc_noreturn __attribute__((noreturn))
87 #define gcc_packed __attribute__((packed))
88 #define gcc_printf(a,b) __attribute__((format(printf, a, b)))
89 #define gcc_pure __attribute__((pure))
90 #define gcc_sentinel __attribute__((sentinel))
91 #define gcc_unused __attribute__((unused))
92 #define gcc_warn_unused_result __attribute__((warn_unused_result))
93 
94 #define gcc_nonnull(...) __attribute__((nonnull(__VA_ARGS__)))
95 #define gcc_nonnull_all __attribute__((nonnull))
96 
97 #define gcc_likely(x) __builtin_expect (!!(x), 1)
98 #define gcc_unlikely(x) __builtin_expect (!!(x), 0)
99 
100 #define gcc_visibility_hidden __attribute__((visibility("hidden")))
101 #define gcc_visibility_default __attribute__((visibility("default")))
102 
103 #define gcc_always_inline __attribute__((always_inline))
104 
105 #else
106 
107 /* generic C compiler */
108 
109 #define gcc_const
110 #define gcc_deprecated
111 #define gcc_may_alias
112 #define gcc_malloc
113 #define gcc_noreturn
114 #define gcc_packed
115 #define gcc_printf(a,b)
116 #define gcc_pure
117 #define gcc_sentinel
118 #define gcc_unused
119 #define gcc_warn_unused_result
120 
121 #define gcc_nonnull(...)
122 #define gcc_nonnull_all
123 
124 #define gcc_likely(x) (x)
125 #define gcc_unlikely(x) (x)
126 
127 #define gcc_visibility_hidden
128 #define gcc_visibility_default
129 
130 #define gcc_always_inline inline
131 
132 #endif
133 
134 #if CLANG_OR_GCC_VERSION(4,3)
135 
136 #define gcc_hot __attribute__((hot))
137 #define gcc_cold __attribute__((cold))
138 
139 #else /* ! GCC_UNUSED >= 40300 */
140 
141 #define gcc_hot
142 #define gcc_cold
143 
144 #endif /* ! GCC_UNUSED >= 40300 */
145 
146 #if GCC_CHECK_VERSION(4,6)
147 #define gcc_flatten __attribute__((flatten))
148 #else
149 #define gcc_flatten
150 #endif
151 
152 #ifndef __cplusplus
153 /* plain C99 has "restrict" */
154 #define gcc_restrict restrict
155 #elif CLANG_OR_GCC_VERSION(4,0)
156 /* "__restrict__" is a GCC extension for C++ */
157 #define gcc_restrict __restrict__
158 #else
159 /* disable it on other compilers */
160 #define gcc_restrict
161 #endif
162 
163 #ifndef __has_feature
164  // define dummy macro for non-clang compilers
165  #define __has_feature(x) 0
166 #endif
167 
168 #if __has_feature(attribute_unused_on_fields)
169 #define gcc_unused_field gcc_unused
170 #else
171 #define gcc_unused_field
172 #endif
173 
174 #if defined(__GNUC__) || defined(__clang__)
175 #define gcc_unreachable() __builtin_unreachable()
176 #else
177 #define gcc_unreachable()
178 #endif
179 
180 #endif