Let basic_tick() of 'task1' and 'basic_quick' of 'task4' run in different threads, and insert an artificial delay in timer_purge() to cause an existing race condition to appear.
Let basic_tick() of 'task1' and 'basic_quick' of 'task4' run in different threads, and insert an artificial delay in timer_purge() to cause an existing race condition to appear.