Linking to libopenal.a causes duplicated symbol error

[fuzhouch]

Hi,

I'm working on a project to build Hashlink against 100% static libraries, which targets creating a binary that can be copied and use in any Linux distro. However when I link against a static libopenal.a, gcc complains a lot of "duplicated symbol" errors.

I have spotted the root cause: it's because AL_IMPORT() and ALC_IMPORT() macros apply a trick when loading extensions, that they define a global function pointer, with same name of corresponding openal-soft functions. Then the function pointers are loaded via alc_load_extensions(). For example:

    alBufferDataStatic = (TYPE_CAST)alGetProcAddress("alBufferDataStatic");

When linking against a static libopenal.a, the function pointer variables and functions have naming conflict, thus causes compiler complains.

I have a private fix by modifying AL_IMPORT() and ALC_IMPORT() macros, to use add function pointers with _dyn suffix. It verified it with my own build environment project.

I'm happy to contribute, but I would like to understand the history what why the trick was applied. What's more, I can see the extension functions have existed in openal-soft and OpenAL, so looks like there's no need to do a if-exist-and-load trick. Or, if we can call the functions directly, it will be even easier.

Any feedbacks will be appricated.