mxgdb-1.2.1: description + notes
mxgdb is a Motif based graphical user interface to the gdb debugger under the X Window System. It provides visual feedback and mouse input for the user to control program execution through breakpoints, to examine and traverse the function call stack, to display values of variables and data structures, to browse source files and functions and to obtain help on gdb commands and options.

This program is rather old; you may want to try using ddd instead.

This product installs its application defaults file in /usr/freeware/lib/X11/app-defaults, which is not on the default X search path. The default values are built into the program, so if you wish to override them you must modify the X search path to include the freeware app-defaults directory.

There are several ways to extend your X search path. The XUSERFILESEARCHPATH, XAPPLRESDIR, XFILESEARCHPATH, and XENVIRONMENT environment variables all affect resource file loading. The easiest methods are to either create a symlink in /usr/lib/X11/app-defaults or to add code similar to this to your startup scripts: 

   % export XUSERFILESEARCHPATH=\
   ${XUSERFILESEARCHPATH:+${XUSERFILESEARCHPATH}:}\
   /usr/freeware/lib/X11/%T/%N%C%S:\
   /usr/freeware/lib/X11/%T/%N%S:\
   /usr/freeware/lib/X11/app-defaults/%N%C%S:\
   /usr/freeware/lib/X11/app-defaults/%N%S
(The line wrapping above is for clarity; you can remove it and any extra whitespace. If XUSERFILESEARCHPATH is already set we append the new directories separated by a colon, otherwise we simply set it to the new colon-separated list.)
To auto-install this package, go back and click on the respective install icon.