Thanks @jback, I see that the two small points I raised are implemented in rEVTGEN24d37621f536

A few thoughts on the modernisation and general tidy-ups:

Just a couple of minor queries. They are genuine questions but I do this largely to try out the code auditing procedures in Phabricator ;)

FYI, quite a nice way of getting a consistent environment for testing these things is to do something like the following (this should work on any system with cvmfs installed):
source /cvmfs/sft.cern.ch/lcg/views/setupViews.sh LCG_94 x86_64-centos7-gcc8-opt
(I'm assuming you're in bash here)
You can obviously modify the LCG version and the platform etc. as you wish.
NB that for the above one you'll need to use C++17
One other nice feature of using LCG views to set the environment is that these LCG releases contain some of our dependencies, so we don't have to mess around building them ourselves necessarily. They seem to get automatically picked up by cmake - as least this worked for HepMC2 when I tried it just now.