I'm in the process of moving from Linux to OS X and I've got 40+ years of Fortran code that I'll be wanting to compile/link/run. I've got gfortran installed (Mavericks) and have it working in Terminal (although debugging tools are a bit on the lousy side), and am thinking maybe I'd like to be using Xcode 6 as a way forward with these codes. I know lots about Fortran, but zero about Xcode. How do I go about using Xcode with gfortran in such a way that I can make use of Xcode debugging, and perhaps downstream putting Swift-based GUI front-ends on my Fortran back-end codes. If gfortran isn't the best choice of Fortran compiler for use with Xcode, what is?