Furnace crashes when attempting a WAV export (macOS and Android)

[host12prog]

there are actually 2 variants:

• variant 1: Furnace will crash BEFORE attempting to make a WAV file
• variant 2: Furnace will crash AFTER attempting to make a WAV file (always guaranteed to happen)

how to reproduce variant 1:

• open Furnace and immediately open a module
• Song > Export > Audio > Export
• there is a chance that Furnace will crash before rendering anything causing a corrupted WAV file

how to reproduce variant 2:

• open Furnace and play the module (this prevents Furnace from crashing before it renders)
• while the module is playing, Song > Export > Audio > Export
• the song WILL render this time, but will crash after it is done rendering

on variant 2: Eknous did a bit of investigation and it appears that the app is segfaulting after rendering the WAV file, and has pinpointed it down to a line in src/audio/sdlAudio.cpp, line 49:

SDL_CloseAudioDevice(ai);

i haven't investigated variant 1, but i'd imagine that it is crashing because no audio devices have been opened, while in variant 2, an audio device HAS been opened (because of the playback), so it will render just fine

[tildearrow]

The problem is that I fail to reproduce this issue.
I wonder why does closing audio device result in a crash...

[tildearrow]

Build Git master. I have pushed a possible fix.

[tildearrow]

It still crashes...