Just to let you know that the same guy is running a series of 15 minute webinars this week on how to become a GDB pro. First one is today (4pm London). http://undo.io/become-gdb-power-user/
We are used to using GDB for debugging C and C++ but it can also be used to debug other languages including Fortran, D, Go and Ada. The Undo team shows a simple example of how to debug Fortran programs, using features provided by GDB and gfortran.