sS checkStandardFunctionForSafety(S fname) {
  S listName = "JavaX Identifier Safety";
  Set<S> identifiers = setMinus(tok_allIdentifiers(textOfStandardFunction(fname)), fname);
  
  // TODO: should lock on map
  Set<S> statuses = treeSet();
  final SS map = mechHashMap_fresh(listName);
  bool changes = false;
  for (S id : identifiers) {
    S status = map.get(id);
    if (status == null)
      if (mapPut_trueIfChanged(map, id, status = "?")) set changes;
    statuses.addAll(tokSplitAtComma(status));
  }
  S status = or2(joinWithComma(simplifySafetyTags(statuses)), "?");
  if (mapPut_trueIfChanged(map, fname, status)) set changes;
  if (changes)
    uploadMechMap(listName, map);
  ret status;
}