The output for eps<0 is done using fprintf, which is bad anyway, and can potentially lead to problems with large output files - not to mention how to deal with this in a multi-process MPI run. This only disables the crude output. It does not change the behaviour of the code itself.
Instantiation of all three versions is needed in any case, and making this explicit potentially reduces copies of the same code used in different files.
These two changes are implemented the pull request