If you know roughly where a bug is occurring in the code, you can often debug it by temporarily inserting printf or std::cout << statements in the code. But for more complex problems it can be more informative and quicker in the long run to create a debugging build (i.e., one with debugging symbols and perhaps with compiler optimizations disabled) and run the program in a debugger. This section provides general information on running OOMMF in a debugger, including short examples in three common debuggers: gdb, lldb, and Visual Studio Debugger.
First edit the configuration files for debugging, as explained in the Configuration files section. Then run
$ tclsh oommf.tcl pimake distclean $ tclsh oommf.tcl pimaketo create a build of OOMMF with debugging symbols. After this you can load an OOMMF executable into a debugger, run the program, and examine its execution. (Remember to bypass the oommf.tcl bootstrap.) There are many debuggers available, some with multiple front-ends. But one overriding criterion in selecting a debugger is to choose one that supports the debugging symbol format output by your C++ compiler. To provide a brief taste of this subject, we will look at three debuggers: GNU’s venerable gdb for use with g++, the lldb debugger packaged with Xcode/clang++ on macOS, and the debugger built into Microsoft’s Visual Studio for use with Visual C++ cl binaries.