makoto@harry  0:20:50/980604(...making/emacs-20.2.94)> gdb src/emacs
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GDB 4.16 (powerpc-unknown-linux --target ppc-unknown-linux), 
Copyright 1996 Free Software Foundation, Inc...
(gdb) br x_window
Breakpoint 1 at 0x24f24c: file xfns.c, line 2722.
(gdb) br lw_create_widget 
Breakpoint 2 at 0x3020fc: file /usr/src/making/emacs-20.2.94/lwlib/lwlib.c, line 900.
(gdb) run
Starting program: /usr/src/making/emacs-20.2.94/src/emacs 

Breakpoint 1, x_window (f=0x563f00, window_prompting=3997696, minibuffer_only=3997696) at xfns.c:2722
2722      BLOCK_INPUT;
(gdb) c
Continuing.

Breakpoint 2, lw_create_widget (type=0x30a538 "main", name=0x30a540 "pane", id=2147478328, val=0x0, 
    parent=0x53ba00, pop_up_p=0 '\000', pre_activate_cb=0, selection_cb=0, post_activate_cb=0)
    at /usr/src/making/emacs-20.2.94/lwlib/lwlib.c:900
900       lw_register_widget (type, name, id, val, pre_activate_cb, selection_cb,
(gdb) c
Continuing.

Breakpoint 2, lw_create_widget (type=0x307a54 "menubar", name=0x307a54 "menubar", id=116, 
    val=0x577780, parent=0x563200, pop_up_p=0 '\000', 
    pre_activate_cb=0x21a968 <popup_activate_callback>, 
    selection_cb=0x21a978 <menubar_selection_callback>, 
    post_activate_cb=0x21abc0 <popup_deactivate_callback>)
    at /usr/src/making/emacs-20.2.94/lwlib/lwlib.c:900
900       lw_register_widget (type, name, id, val, pre_activate_cb, selection_cb,
(gdb) c
Continuing.
Error: Unresolved inheritance operation

Program exited with code 01.
(gdb)