[Freeciv-Dev] (PR#3512) gtk2 crash

["Jason Short" <jdorje@xxxxxxxxxxxxxxxxxxxxx>]

I did the following:

- Detached the overview panel (clicked on the button for it).
- Closed the new overview window; it reattached (at the bottom).
- Detached the info panel (the one that's usually below the overview).
- Tried to detach the overview panel, except this time it didn't turn
into a window.

At this point I got a few warnings like:

(civclient:17288): Gdk-CRITICAL **: file gdkdraw.c: line 368
(gdk_draw_line): assertion `drawable != NULL' failed

then I started getting warnings like this one, every half-second or so:

(civclient:17288): Gdk-CRITICAL **: file gdkdraw.c: line 410
(gdk_draw_rectangle): assertion `GDK_IS_DRAWABLE (drawable)' failed

Finally, after about 10 seconds civclient crashed.  I'm not sure if I
did anything to trigger this.

#0  0x402417e2 in gdk_draw_rectangle () from /usr/lib/libgdk-x11-2.0.so.0
(gdb) bt
#0  0x402417e2 in gdk_draw_rectangle () from /usr/lib/libgdk-x11-2.0.so.0
#1  0x0809934d in overview_update_tile (x=8, y=60) at mapview.c:614
#2  0x08070826 in refresh_tile_mapcanvas (x=8, y=30, write_to_screen=true)
    at mapview_common.c:101
#3  0x0806a825 in blink_active_unit () at control.c:357
#4  0x0806706c in real_timer_callback () at civclient.c:813
#5  0x08092e93 in timer_callback (data=0x0) at gui_main.c:1132

Some other information from gdb:

(gdb) p overview_canvas_store
$1 = (GdkPixmap *) 0x83ac638
(gdb) p *overview_canvas_store
$2 = {parent_instance = {g_type_instance = {g_class = 0x8295e98}, 
    ref_count = 1, qdata = 0x0}}
(gdb) p overview_canvas->window
$3 = (GdkWindow *) 0x696e6e75
(gdb) p *overview_canvas->window
Cannot access memory at address 0x696e6e75

This appears to be reproducable.  It seems likely that it affects the
GTK client, as well.

jason