• Fix the last of the threading bugs that were introduced as far back as 1.38 in 2001. Break out of the FOREACH_THREAD_IN_PROC loop when we've discovered a new proc in the chain.
• Increment i and check for maxlockdepth once per matching process not once per thread. This didn't properly terminate the loop before.
• Fix a bug which has existed potentially since rev 1.1. waitblock->lf_next can be NULL when a thread has been woken-up but not yet scheduled. Check for this condition rather than blindly dereferencing.

Found by: libMicro