There are a number of techniques for solving this: 1. use a GC'd language 2. hazard pointers 3. epoch-based GC 4. collect nodes when a user des

There are a number of techniques for solving this: 1. use a GC'd language 2. hazard pointers 3. epoch-based GC 4. collect nodes when a user destroys the structure (user is required to guarantee that destruction is single-threaded). There are probably others.