VM crashes when a synchronized method is called

[Jan Vraný]

This may happen (and it happens) when:

1. Intepreted method tries to acquire the monitor (i.e., before any bytecode is executed)
2. Context switch happen (such as when there's a contention), so MKREAL() is called

Then the MKREAL() causes SEGV as the context is not initialized properly and/or MKREAL() makes wrong assumption about it.

[Jan Vraný]

Fixed in librun 1923f9c65546