php backtraces with gdb print gibberish for function name

I have have a PHP script that is core dumping, I'm trying to find out exactly where. I carefully followed the instructions on http://bugs.php.net/bugs-generating-backtrace.php with a little help in creating an apache debug build using: http://www.bowiesnyder.com/writings/gdb_apache.htm however, when I get to the end bit where it's supposed to print out the function that was causing the seg fault (I've already typed "frame x" where x is the lowest-numbered execute() call), I get crap: (gdb) print (char *)(executor_globals.function_state_ptr->function)->common.function_name $2 = 0x83a2be0 "´\221/\b\024àJ\bÜï[\b´ì0\b" where it should say, according to the bugs.php.net page above, something like: (gdb) print (char *)(executor_globals.function_state_ptr->function)->common.function_name $14 = 0x80fa6fa "pg_result_error" I can't find any docs anywhere on what else I can ask executor_globals for... getting executor_globals.active_op_array->function_name returns one of my functions, but that's not terribly useful without knowing what line of it caused the segfault. Any suggestions for futher probing? joe