+ uint64_t switch_thread(ModelAction *act);
+
+ void continueExecution(Thread *old);
+ void finishExecution(Thread *old);
+ void consumeAction();
+ void chooseThread(ModelAction *act, Thread *old);
+ Thread * getNextThread();
+ void handleChosenThread(Thread *old);
+ void handleNewValidThread(Thread *old, Thread *next);
+
+ void assert_bug(const char *msg, ...);