I tried all three versions both installed and recent repository builds and verified that the overt issue is limited to 3.4. I agree that the exception message suggests stopping with the first exception. Since there is a small cost to try: and break, I am inclined to move the try back out of the loop. The only thing it could mask is a problem with self.handlerids, and I would expect that if that is corrupted or missing, there would be problems before shutdown.

I know that in 3.4, shutdown order has been modified and the wording of the warning was discussed on pydev. I do not know (and do not care at the moment) if either ignoring __del__ exceptions or warning about them is new in 3.4. What I do remember from the discussion is agreement that 1. __del__ exceptions should be caught so shutdown can continue; 2. a warning should be given in case the exception indicates a bug in __del__; and 3. __del__ writers are responsible to catch exceptions that do not indicate a bug, so as to avoid the warning. So I am inclined to backport to all versions.