1 /*
2  * Copyright (C) 2003-2013 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 #else
34 #  define CLANG_VERSION 0
35 #endif
36 
37 /**
38  * Are we building with the specified version of gcc (not clang or any
39  * other compiler) or newer?
40  */
41 #define GCC_CHECK_VERSION(major, minor) \
42   (!CLANG_VERSION && \
43    GCC_VERSION >= GCC_MAKE_VERSION(major, minor, 0))
44 
45 /**
46  * Are we building with clang (any version) or at least the specified
47  * gcc version?
48  */
49 #define CLANG_OR_GCC_VERSION(major, minor) \
50   (CLANG_VERSION || GCC_CHECK_VERSION(major, minor))
51 
52 /**
53  * Are we building with gcc (not clang or any other compiler) and a
54  * version older than the specified one?
55  */
56 #define GCC_OLDER_THAN(major, minor) \
57   (GCC_VERSION && !CLANG_VERSION && \
58    GCC_VERSION < GCC_MAKE_VERSION(major, minor, 0))
59 
60 #if CLANG_OR_GCC_VERSION(4,0)
61 
62 /* GCC 4.x */
63 
64 #define gcc_const __attribute__((const))
65 #define gcc_deprecated __attribute__((deprecated))
66 #define gcc_may_alias __attribute__((may_alias))
67 #define gcc_malloc __attribute__((malloc))
68 #define gcc_noreturn __attribute__((noreturn))
69 #define gcc_packed __attribute__((packed))
70 #define gcc_printf(a,b) __attribute__((format(printf, a, b)))
71 #define gcc_pure __attribute__((pure))
72 #define gcc_sentinel __attribute__((sentinel))
73 #define gcc_unused __attribute__((unused))
74 #define gcc_warn_unused_result __attribute__((warn_unused_result))
75 
76 #define gcc_nonnull(...) __attribute__((nonnull(__VA_ARGS__)))
77 #define gcc_nonnull_all __attribute__((nonnull))
78 #define gcc_returns_nonnull __attribute__((returns_nonnull))
79 
80 #define gcc_likely(x) __builtin_expect (!!(x), 1)
81 #define gcc_unlikely(x) __builtin_expect (!!(x), 0)
82 
83 #define gcc_aligned(n) __attribute__((aligned(n)))
84 
85 #define gcc_visibility_hidden __attribute__((visibility("hidden")))
86 #define gcc_visibility_default __attribute__((visibility("default")))
87 
88 #define gcc_always_inline __attribute__((always_inline))
89 
90 #else
91 
92 /* generic C compiler */
93 
94 #define gcc_const
95 #define gcc_deprecated
96 #define gcc_may_alias
97 #define gcc_malloc
98 #define gcc_noreturn
99 #define gcc_packed
100 #define gcc_printf(a,b)
101 #define gcc_pure
102 #define gcc_sentinel
103 #define gcc_unused
104 #define gcc_warn_unused_result
105 
106 #define gcc_nonnull(...)
107 #define gcc_nonnull_all
108 #define gcc_returns_nonnull
109 
110 #define gcc_likely(x) (x)
111 #define gcc_unlikely(x) (x)
112 
113 #define gcc_aligned(n)
114 
115 #define gcc_visibility_hidden
116 #define gcc_visibility_default
117 
118 #define gcc_always_inline inline
119 
120 #endif
121 
122 #if CLANG_OR_GCC_VERSION(4,3)
123 
124 #define gcc_hot __attribute__((hot))
125 #define gcc_cold __attribute__((cold))
126 
127 #else /* ! GCC_UNUSED >= 40300 */
128 
129 #define gcc_hot
130 #define gcc_cold
131 
132 #endif /* ! GCC_UNUSED >= 40300 */
133 
134 #if GCC_CHECK_VERSION(4,6)
135 #define gcc_flatten __attribute__((flatten))
136 #else
137 #define gcc_flatten
138 #endif
139 
140 #ifndef __cplusplus
141 /* plain C99 has "restrict" */
142 #define gcc_restrict restrict
143 #elif CLANG_OR_GCC_VERSION(4,0)
144 /* "__restrict__" is a GCC extension for C++ */
145 #define gcc_restrict __restrict__
146 #else
147 /* disable it on other compilers */
148 #define gcc_restrict
149 #endif
150 
151 /* C++11 features */
152 
153 #if defined(__cplusplus)
154 
155 #endif
156 
157 #ifndef __has_feature
158   // define dummy macro for non-clang compilers
159   #define __has_feature(x) 0
160 #endif
161 
162 #if __has_feature(attribute_unused_on_fields)
163 #define gcc_unused_field gcc_unused
164 #else
165 #define gcc_unused_field
166 #endif
167 
168 #if defined(__GNUC__) || defined(__clang__)
169 #define gcc_unreachable() __builtin_unreachable()
170 #else
171 #define gcc_unreachable()
172 #endif
173 
174 #endif
175