Why destroy notify callback inputs wrong?

[learfox furry ao net]

I have a destroy callback for a gtk window, however when that window
is unref'ed (gtk_widget_unref()) the destroy signal callback is called
but given wrong inputs.

#2  0x807e6c9 in TexBrowserCloseCB (widget=0x8249c40, event=0x816c278, 
    data=0x401f4578) at texbrowsercb.c:1925
#3  0x401650fd in gtk_marshal_NONE__NONE ()
#4  0x4019284d in gtk_handlers_run ()
#5  0x40191c92 in gtk_signal_real_emit ()
#6  0x4018fd95 in gtk_signal_emit ()
#7  0x401759e3 in gtk_object_shutdown ()
#8  0x401c86c0 in gtk_widget_shutdown ()
#9  0x401caf53 in gtk_window_shutdown ()
#10 0x4017598b in gtk_object_destroy ()
#11 0x401c16b6 in gtk_widget_destroy ()
#12 0x807a0ee in TexBrowserDestroy (tb=0x816c278) at texbrowser.c:1486
#13 0x805aa2d in EditorDelete (editor=0x816c038) at editor.c:2337
#14 0x80a68d9 in MAShutdownCB (core_ptr=0x8125900) at vmacb.c:89
#15 0x80755b8 in main (argc=1, argv=0xbffff954) at main.c:438
#16 0x405b7cb3 in __libc_start_main (main=0x8074fc8 <main>, argc=1, 
    argv=0xbffff954, init=0x8052778 <_init>, fini=0x80b7844 <_fini>, 
    rtld_fini=0x4000a350 <_dl_fini>, stack_end=0xbffff94c)
    at ../sysdeps/generic/libc-start.c:78

As you can see on frame #1 data=0x401f4578, but it should be 0x816c278,
since the signal callback was set to pass the data as tb=0x816c278.


--
Sincerely,                  ,"-_                         \|/
-Capt. Taura M.             ,   O=__                    --X--
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                  http://furry.ao.net/~learfox/