[Python-Dev] How to debug pyexpat SIGSEGV with GDB?

[Skip Montanaro]

    >> So, how can I figure out where in the Python source the function call
    >> is coming from using gdb? I'm sure it involves "print" and some
    >> casts.. I couldn't find a howto on python.org

    Jeremy> First, make sure that the code from Misc/gdbinit is in your
    Jeremy> .gdbinit file.  Get the stack trace in gdb and move up/down
    Jeremy> until you get to an eval_frame() frame.  Then call the function
    Jeremy> pyframe.  It will print the filename, function name, and line
    Jeremy> number of the current frame.  The lineno usually points to the
    Jeremy> first line of the function.

I have this in my .gdbinit file:

    define ppystack
        while $pc < Py_Main || $pc > Py_GetArgcArgv
            if $pc > eval_frame && $pc < PyEval_EvalCodeEx
                set $__fn = PyString_AsString(co->co_filename)
                set $__n = PyString_AsString(co->co_name)
                printf "%s (%d): %s\n",  $__fn, f->f_lineno, $__n
            end
            up-silently 1
        end
        select-frame 0
    end

Skip