From someone who is working with our code:
In debugging another project I discovered that the Intel Fortran automatic vectorizer is apparently broken in current 13.1 and 14.0, emitting bad code for some loop constructs. (I am only using the Windows versions so I can't say whether the Linux compilers are also broken but I would expect vectorizer code to be h/w specific but cross-platform.) The vectorizer is active automatically at /O2 and /O3 optimization level. I have disabled it with the /Qvec- option. I thought this might help you avoid some debugging hours at some point.
It also sounds like 14.0 is not production-ready with some vital fixes in the works for the first update, so it might be best to defer on switching to it.
From me: Is this true? Should we just go back to V13?