[openal] Alure problem with vs2013

[Chris Robinson]

On 05/14/2015 08:40 AM, developer at oldunreal.com wrote:
> I rebuilt all my project files with visual studio 2013 when I moved to
> this platform. Now I have a problem with alure-1.2 - using cmake already
> was a bit of a problem since it is asking for some VORBISENC_LIBRARY
> which I am already unable to find - and still have no clue where to get
> it from, vorbis only contains vorbisenc.exe and not some lib.

Odd, Alure itself doesn't use a vorbisenc lib. FindOggVorbis.cmake will 
look for one and add it to the list of libraries if it's found, but if 
it's not found it should be ignored by cmake.

> Anyway the real problem is, no matter what I try, alure doesn't seem to
> be able to play any of the additional filetypes I tried (ogg, flac and
> mp3). Trying to play any of these always results in "Unsupported Type".
> It doesn't make any difference if I try it statically or dynamically
> linked.

Hmm. does cmake list VorbisFile, FLAC, or SndFile as supported in its 
message output? Assuming it does, there's not too much I can think of 
that could be the problem.

Alure 1.x uses global object initialization to self-register the 
built-in set of decoders. I've run into problems before of over- 
enthusiastic compiler optimizations completely removing such objects so 
the constructors are never run (thus the codecs are never properly 
registered). I'd be surprised that it's affecting even a DLL build 
though, since the 1.2 release does a number of things to try and make 
the compiler not optimize the objects away. But I suppose a really 
super-aggressive optimizer can still find ways to convince itself to get 
rid of them.

This is one of the things I set out to fix with Alure 2.0 (along with 
many other things), since I couldn't figure out a proper fix that didn't 
break ABI, expose internals, or necessitate a redesign anyway.

I suppose a quick-fix workaround might be to edit the codec_* sources 
and change the 'static DecoderDecl...' to 'ALURE_API DecoderDecl...', 
and hope that stops the optimizer from dropping the objects, assuming 
that's the problem.