Who says they're random? Just because they seem random doesn't mean they are. I bet no one has tried to record a movie of it, and see if playing it back results in the same crash.
I tased spider man when it crashed constantly in JIT, and failed to even boot. And i did it in JIT. All i had to do was boot in interp, then switch to jit. Of course it still crashed randomly then, but it wasn't a problem. Because guess what? It wasn't really random. If it crashed, all i had to do was do something slightly different to avoid it, and then walah, it played back perfectly, magically avoid every "random" crash.
I tased spider man when it crashed constantly in JIT, and failed to even boot. And i did it in JIT. All i had to do was boot in interp, then switch to jit. Of course it still crashed randomly then, but it wasn't a problem. Because guess what? It wasn't really random. If it crashed, all i had to do was do something slightly different to avoid it, and then walah, it played back perfectly, magically avoid every "random" crash.