Well, the crash comes and goes with changes in the code, but when it does crash, all I have done is call al_init and al_install functions (through my library). I tried to replicate it but cannot so far.
D3D binary incompatiblity maybe? I don't know what would cause a crash sometimes and not others.
If I can, I'll build allegro from git and see if I can reproduce it later. It will take a little while though.