"Error: unable to read module BG/Q data from log file" in darshan-diff utility

pcarns_mpi-io-test_id12594_9-18-53686-17287241849796474061_1.darshan pcarns_mpi-io-test_id12593_9-18-53685-12122538308779795328_1.darshan

Files to reproduce are attached; these were generated with origin/master and two single-process runs of mpi-io-test. Example:

pcarns@carns-x1:~$ darshan-diff pcarns_mpi-io-test_id12593_9-18-53685-12122538308779795328_1.darshan pcarns_mpi-io-test_id12594_9-18-53686-17287241849796474061_1.darshan
- # start_time: 1474224885
+ # start_time: 1474224886
- # end_time: 1474224885
+ # end_time: 1474224886
Error: unable to read module BG/Q data from log file.
Error: unable to build record hash for darshan log file pcarns_mpi-io-test_id12593_9-18-53685-12122538308779795328_1.darshan.

Relevant to issue #194 (closed) , need to make sure that darshan-diff works with stdio records. I think it may be close already but there are a couple of weird things going on that don't seem to be stdio-related.