1 /*

     2  * copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>

     3  *

     4  * This file is part of Libav.

     5  *

     6  * Libav 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  * Libav 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 Libav; 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) (__GNUC__ > x || __GNUC__ == x && __GNUC_MINOR__ >= y)

    31 #else

    32 #    define AV_GCC_VERSION_AT_LEAST(x,y) 0

    33 #endif

    34 

    35 #if AV_GCC_VERSION_AT_LEAST(3,1)

    36 #    define av_always_inline __attribute__((always_inline)) inline

    37 #elif defined(_MSC_VER)

    38 #    define av_always_inline __forceinline

    39 #else

    40 #    define av_always_inline inline

    41 #endif

    42 

    43 #if AV_GCC_VERSION_AT_LEAST(3,1)

    44 #    define av_noinline __attribute__((noinline))

    45 #else

    46 #    define av_noinline

    47 #endif

    48 

    49 #if AV_GCC_VERSION_AT_LEAST(3,1)

    50 #    define av_pure __attribute__((pure))

    51 #else

    52 #    define av_pure

    53 #endif

    54 

    55 #if AV_GCC_VERSION_AT_LEAST(2,6)

    56 #    define av_const __attribute__((const))

    57 #else

    58 #    define av_const

    59 #endif

    60 

    61 #if AV_GCC_VERSION_AT_LEAST(4,3)

    62 #    define av_cold __attribute__((cold))

    63 #else

    64 #    define av_cold

    65 #endif

    66 

    67 #if AV_GCC_VERSION_AT_LEAST(4,1)

    68 #    define av_flatten __attribute__((flatten))

    69 #else

    70 #    define av_flatten

    71 #endif

    72 

    73 #if AV_GCC_VERSION_AT_LEAST(3,1)

    74 #    define attribute_deprecated __attribute__((deprecated))

    75 #else

    76 #    define attribute_deprecated

    77 #endif

    78 

    79 #if defined(__GNUC__)

    80 #    define av_unused __attribute__((unused))

    81 #else

    82 #    define av_unused

    83 #endif

    84 

    85 /**

    86  * Mark a variable as used and prevent the compiler from optimizing it

    87  * away.  This is useful for variables accessed only from inline

    88  * assembler without the compiler being aware.

    89  */

    90 #if AV_GCC_VERSION_AT_LEAST(3,1)

    91 #    define av_used __attribute__((used))

    92 #else

    93 #    define av_used

    94 #endif

    95 

    96 #if AV_GCC_VERSION_AT_LEAST(3,3)

    97 #   define av_alias __attribute__((may_alias))

    98 #else

    99 #   define av_alias

   100 #endif

   101 

   102 #if defined(__GNUC__) && !defined(__ICC)

   103 #    define av_uninit(x) x=x

   104 #else

   105 #    define av_uninit(x) x

   106 #endif

   107 

   108 #ifdef __GNUC__

   109 #    define av_builtin_constant_p __builtin_constant_p

   110 #    define av_printf_format(fmtpos, attrpos) __attribute__((__format__(__printf__, fmtpos, attrpos)))

   111 #else

   112 #    define av_builtin_constant_p(x) 0

   113 #    define av_printf_format(fmtpos, attrpos)

   114 #endif

   115 

   116 #if AV_GCC_VERSION_AT_LEAST(2,5)

   117 #    define av_noreturn __attribute__((noreturn))

   118 #else

   119 #    define av_noreturn

   120 #endif

   121 

   122 #endif /* AVUTIL_ATTRIBUTES_H */