There are a few invalid accesses to arrays happening inside of BiggieSE as well as typecast issues.
For example:
https://github.com/mongodb/mongo/blob/master/src/mongo/db/storage/biggie/store.h#L652 was not typecast.
https://github.com/mongodb/mongo/blob/master/src/mongo/db/storage/biggie/store.h#L570 should be an integer, not a char.