OpenMP is great. I’ve done something similar to your second case (thread local objects that are filled in parallel and later combined). In the case of “OpenMP off” (pragmas ignored), is it possible to avoid the overhead of the thread local object essentially getting copied into the final object (since no OpenMP means only a single thread local object)? I avoided this by implementing a separate code path, but I’m just wondering if there are any tricks I missed that would allow still a single code path