Help in debugging the DirectFB backend

[Attilio Fiandrotti <fiandro tiscali it>]

Hi

While running gtk applications with the dfb backend i often (but not 
always) run into a crash that is not reproducible at all with X and 
hence i think it should be related to cairo-dfb or gdk-dfb.
I'm usually able to reproduce it by running the gtk-demo app, opening 
the hypertext application and closing it with meta-c.
At the third gtk_text_layout_set_buffer() call after the window is told 
to close, buffer is received valid, but when  g_return_if_fail 
(GTK_IS_TEXT_LAYOUT (layout)) is executed (line 289), control goes back 
to line 288 (and buffer is still ok), then line 289 is executed again 
and buffer is now null, causing a crash later.
I think cairodfb or gdkdfb must previously have corrupted memory 
somewhere, but i can't detect when nor where: can anyone reproduce this 
or give me an hint about how to catch it?

thanks

Attilio

gtktextlayout.c

285 void
286 gtk_text_layout_set_buffer (GtkTextLayout *layout,
287                             GtkTextBuffer *buffer)
288 {
289   g_return_if_fail (GTK_IS_TEXT_LAYOUT (layout));