Depending on the type of the map passed to a record map constructor, records will not correctly compare for equality:
Cause: The type of the map passed into the map constructor leaks into the __extmap, affecting equality comparison of the record. This bug was described in this post: https://groups.google.com/forum/#!topic/clojure/iN-SPBaTFUw
Approach: Clean the extmap before putting it into the record constructor.
Screened by: Alex Miller