When viewing a diff on a page with no other items in the history (see link), it shows a link to the newer edit. Upon clicking, it shows the new edit next to the old, with no differences (obviously). If there is only one edit in the history, I think disabling the diff interface entirely would be the best course of action.

Version: 1.11.x
Severity: normal
URL: http://en.wikipedia.org/w/index.php?title=User:^demon/test&diff=prev&oldid=161607707