attributes.h (4889B)
1 /* 2 * copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at> 3 * 4 * This file is part of FFmpeg. 5 * 6 * FFmpeg 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 * FFmpeg 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 FFmpeg; if not, write to the Free Software 18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 19 */ 20 21 /** 22 * @file 23 * Macro definitions for various function/variable attributes 24 */ 25 26 #ifndef AVUTIL_ATTRIBUTES_H 27 #define AVUTIL_ATTRIBUTES_H 28 29 #ifdef __GNUC__ 30 # define AV_GCC_VERSION_AT_LEAST(x, y) \ 31 (__GNUC__ > (x) || __GNUC__ == (x) && __GNUC_MINOR__ >= (y)) 32 # define AV_GCC_VERSION_AT_MOST(x, y) \ 33 (__GNUC__ < (x) || __GNUC__ == (x) && __GNUC_MINOR__ <= (y)) 34 #else 35 # define AV_GCC_VERSION_AT_LEAST(x, y) 0 36 # define AV_GCC_VERSION_AT_MOST(x, y) 0 37 #endif 38 39 #ifdef __has_builtin 40 # define AV_HAS_BUILTIN(x) __has_builtin(x) 41 #else 42 # define AV_HAS_BUILTIN(x) 0 43 #endif 44 45 #ifndef av_always_inline 46 # if AV_GCC_VERSION_AT_LEAST(3, 1) 47 # define av_always_inline __attribute__((always_inline)) inline 48 # elif defined(_MSC_VER) 49 # define av_always_inline __forceinline 50 # else 51 # define av_always_inline inline 52 # endif 53 #endif 54 55 #ifndef av_extern_inline 56 # if defined(__ICL) && __ICL >= 1210 || defined(__GNUC_STDC_INLINE__) 57 # define av_extern_inline extern inline 58 # else 59 # define av_extern_inline inline 60 # endif 61 #endif 62 63 #if AV_GCC_VERSION_AT_LEAST(3, 4) 64 # define av_warn_unused_result __attribute__((warn_unused_result)) 65 #else 66 # define av_warn_unused_result 67 #endif 68 69 #if AV_GCC_VERSION_AT_LEAST(3, 1) 70 # define av_noinline __attribute__((noinline)) 71 #elif defined(_MSC_VER) 72 # define av_noinline __declspec(noinline) 73 #else 74 # define av_noinline 75 #endif 76 77 #if AV_GCC_VERSION_AT_LEAST(3, 1) || defined(__clang__) 78 # define av_pure __attribute__((pure)) 79 #else 80 # define av_pure 81 #endif 82 83 #if AV_GCC_VERSION_AT_LEAST(2, 6) || defined(__clang__) 84 # define av_const __attribute__((const)) 85 #else 86 # define av_const 87 #endif 88 89 #if AV_GCC_VERSION_AT_LEAST(4, 3) || defined(__clang__) 90 # define av_cold __attribute__((cold)) 91 #else 92 # define av_cold 93 #endif 94 95 #if AV_GCC_VERSION_AT_LEAST(4, 1) && !defined(__llvm__) 96 # define av_flatten __attribute__((flatten)) 97 #else 98 # define av_flatten 99 #endif 100 101 #if AV_GCC_VERSION_AT_LEAST(3, 1) 102 # define attribute_deprecated __attribute__((deprecated)) 103 #elif defined(_MSC_VER) 104 # define attribute_deprecated __declspec(deprecated) 105 #else 106 # define attribute_deprecated 107 #endif 108 109 /** 110 * Disable warnings about deprecated features 111 * This is useful for sections of code kept for backward compatibility and 112 * scheduled for removal. 113 */ 114 #ifndef AV_NOWARN_DEPRECATED 115 # if AV_GCC_VERSION_AT_LEAST(4, 6) 116 # define AV_NOWARN_DEPRECATED(code) \ 117 _Pragma("GCC diagnostic push") \ 118 _Pragma("GCC diagnostic ignored \"-Wdeprecated-declarations\"") \ 119 code _Pragma("GCC diagnostic pop") 120 # elif defined(_MSC_VER) 121 # define AV_NOWARN_DEPRECATED(code) \ 122 __pragma(warning(push)) __pragma(warning(disable : 4996)) code; \ 123 __pragma(warning(pop)) 124 # else 125 # define AV_NOWARN_DEPRECATED(code) code 126 # endif 127 #endif 128 129 #if defined(__GNUC__) || defined(__clang__) 130 # define av_unused __attribute__((unused)) 131 #else 132 # define av_unused 133 #endif 134 135 /** 136 * Mark a variable as used and prevent the compiler from optimizing it 137 * away. This is useful for variables accessed only from inline 138 * assembler without the compiler being aware. 139 */ 140 #if AV_GCC_VERSION_AT_LEAST(3, 1) || defined(__clang__) 141 # define av_used __attribute__((used)) 142 #else 143 # define av_used 144 #endif 145 146 #if AV_GCC_VERSION_AT_LEAST(3, 3) || defined(__clang__) 147 # define av_alias __attribute__((may_alias)) 148 #else 149 # define av_alias 150 #endif 151 152 #if (defined(__GNUC__) || defined(__clang__)) && !defined(__INTEL_COMPILER) 153 # define av_uninit(x) x = x 154 #else 155 # define av_uninit(x) x 156 #endif 157 158 #if defined(__GNUC__) || defined(__clang__) 159 # define av_builtin_constant_p __builtin_constant_p 160 # define av_printf_format(fmtpos, attrpos) \ 161 __attribute__((__format__(__printf__, fmtpos, attrpos))) 162 #else 163 # define av_builtin_constant_p(x) 0 164 # define av_printf_format(fmtpos, attrpos) 165 #endif 166 167 #if AV_GCC_VERSION_AT_LEAST(2, 5) || defined(__clang__) 168 # define av_noreturn __attribute__((noreturn)) 169 #else 170 # define av_noreturn 171 #endif 172 173 #endif /* AVUTIL_ATTRIBUTES_H */