Question

我在学校有一个小组项目（3D FPS游戏），我在C ++中使用OpenAL和OGG Vorbis编程音频。我们的编译器设置为警告我们有关已定义但未使用的变量，这些变量对Vorbis来说是一个问题。当我编译我们的应用程序时，我得到了这个：

[  8%] Building CXX object CMakeFiles/fps.dir/src/audio/Sound.cpp.o
/home/berzeger/FPS/FPS/trunk/game/src/audio/../../include/vorbis/vorbisfile.h:82:21: warning: ‘OV_CALLBACKS_NOCLOSE’ defined but not used [-Wunused-variable]
/home/berzeger/FPS/FPS/trunk/game/src/audio/../../include/vorbis/vorbisfile.h:89:21: warning: ‘OV_CALLBACKS_STREAMONLY’ defined but not used [-Wunused-variable]
/home/berzeger/FPS/FPS/trunk/game/src/audio/../../include/vorbis/vorbisfile.h:96:21: warning: ‘OV_CALLBACKS_STREAMONLY_NOCLOSE’ defined but not used [-Wunused-variable]
[  9%] Building CXX object CMakeFiles/fps.dir/src/audio/MenuAudioController.cpp.o
/home/berzeger/FPS/FPS/trunk/game/src/audio/../../include/vorbis/vorbisfile.h:75:21: warning: ‘OV_CALLBACKS_DEFAULT’ defined but not used [-Wunused-variable]
/home/berzeger/FPS/FPS/trunk/game/src/audio/../../include/vorbis/vorbisfile.h:82:21: warning: ‘OV_CALLBACKS_NOCLOSE’ defined but not used [-Wunused-variable]
/home/berzeger/FPS/FPS/trunk/game/src/audio/../../include/vorbis/vorbisfile.h:89:21: warning: ‘OV_CALLBACKS_STREAMONLY’ defined but not used [-Wunused-variable]
/home/berzeger/FPS/FPS/trunk/game/src/audio/../../include/vorbis/vorbisfile.h:96:21: warning: ‘OV_CALLBACKS_STREAMONLY_NOCLOSE’ defined but not used [-Wunused-variable]
[ 10%] Building CXX object CMakeFiles/fps.dir/src/audio/GameAudioController.cpp.o
In file included from /home/berzeger/FPS/FPS/trunk/game/src/audio/GameAudioController.cpp:1:0:
/home/berzeger/FPS/FPS/trunk/game/src/audio/../../include/vorbis/vorbisfile.h:75:21: warning: ‘OV_CALLBACKS_DEFAULT’ defined but not used [-Wunused-variable]
/home/berzeger/FPS/FPS/trunk/game/src/audio/../../include/vorbis/vorbisfile.h:82:21: warning: ‘OV_CALLBACKS_NOCLOSE’ defined but not used [-Wunused-variable]
/home/berzeger/FPS/FPS/trunk/game/src/audio/../../include/vorbis/vorbisfile.h:89:21: warning: ‘OV_CALLBACKS_STREAMONLY’ defined but not used [-Wunused-variable]
/home/berzeger/FPS/FPS/trunk/game/src/audio/../../include/vorbis/vorbisfile.h:96:21: warning: ‘OV_CALLBACKS_STREAMONLY_NOCLOSE’ defined but not used [-Wunused-variable]
[ 11%] Building CXX object CMakeFiles/fps.dir/src/audio/AudioController.cpp.o
/home/berzeger/FPS/FPS/trunk/game/src/audio/../../include/vorbis/vorbisfile.h:75:21: warning: ‘OV_CALLBACKS_DEFAULT’ defined but not used [-Wunused-variable]
/home/berzeger/FPS/FPS/trunk/game/src/audio/../../include/vorbis/vorbisfile.h:82:21: warning: ‘OV_CALLBACKS_NOCLOSE’ defined but not used [-Wunused-variable]
/home/berzeger/FPS/FPS/trunk/game/src/audio/../../include/vorbis/vorbisfile.h:89:21: warning: ‘OV_CALLBACKS_STREAMONLY’ defined but not used [-Wunused-variable]
/home/berzeger/FPS/FPS/trunk/game/src/audio/../../include/vorbis/vorbisfile.h:96:21: warning: ‘OV_CALLBACKS_STREAMONLY_NOCLOSE’ defined but not used [-Wunused-variable]

等等。你可以看到这很糟糕，重要的事情很容易丢失。

我似乎无法找到如何抑制vorbis未使用变量的方法。我试过了

#define OV_EXCLUDE_STATIC_CALLBACKS

但禁用了所有vorbis定义，这不是我想要的。

有人可以帮忙吗？提前谢谢！

Answer 1

就我个人而言，我会修改我的构建脚本来过滤掉那些特定的警告，但是如果你不是游戏来做那个......

您可以创建一个包装器头文件，包括包装器文件而不是vorbis头文件，并使用包装器头中的问题变量，以便警告消失。假设它们是整数常量，这样就足够了。

//File: myvorbisfile.h
#include "vorbisfile.h"

// Dummy function in the anonymous namespace 
// to suppress the unused variables
namespace
{
   int hide_unused_variables()
   {
     return 0
      + OV_CALLBACKS_NOCLOSE
      + OV_CALLBACKS_DEFAULT
      ... Fill in the rest ...
    }
}

Answer 2

好的，我想我现在得到了解决方案。我们将头文件复制到我们的app目录中，所以我用这种方式包含了vorbisfile.h：

#include "../../include/vorbis/vorbisfile.h"

当我改变这一行时：

#include <vorbis/vorbisfile.h>

警告消失了。不知道为什么。

OGG Vorbis：定义但未使用 - 如何抑制？

2 个答案: