Hi Giuseppe,
Just as a follow up, we were finally able to obtain a computer running MacOs 10.14 Mojave. What we found was that ITensor compiled without any issues, except perhaps one or two small warnings, when using the compiler flags suggested for MacOS in the options.mk.sample file.
So perhaps if you are still seeing issues it could be related to the fact that you upgraded from 10.13 or perhaps to other complier flags than ours? Our computer was a fresh install of 10.14 I believe.
Best regards,
Miles