static L<Pair<Instance, S>> heapWalker_pathToGCRootWithFieldNames(Instance baseInstance) {
  bool debug = true;
  L<Pair<Instance, S>> path = map(func(Instance i) -> Pair<Instance, S> { pair(i, null) }, heapWalker_pathToGCRoot(baseInstance));
  bigLoop: for (int i = 1; i < l(path); i++) {
    Instance i0 = path.get(i-1).a;
    Instance i1 = path.get(i).a;
    L<FieldValue> fieldValues = i1.getFieldValues();
    if (debug) {
      print("Fields: " + map(fieldValues, func(FieldValue fv) -> S { fv.getField().getName() }));
      print("Types: " + map className(fieldValues));
    }
    for (FieldValue fv : fieldValues)
      if (fv instanceof ObjectFieldValue && ((ObjectFieldValue) fv).getInstance() == i0) {
        path.get(i).b = fv.getField().getName();
        continue bigLoop;
      }
  }
  ret path;
}