Original report:

https://zh.wikipedia.org/w/index.php?title=Wikipedia:%E4%BA%92%E5%8A%A9%E5%AE%A2%E6%A0%88/%E6%8A%80%E6%9C%AF&oldid=21675960#.E6.96.B0BUG

See revisions 21529615, 21529610, 21529605:

• Edits with no change are allowed
• rc_old_len are populated as 0

I guess the code fails to fetch the original revision, thus it cannot check for edits without change, and cannot get old revision length.

We need some reports from the original editors saying what did they do exactly.

Version: unspecified
Severity: normal