+#endif // wxDEBUG_LEVEL && wxUSE_STACKWALKER
+
+bool wxGUIAppTraits::ShowAssertDialog(const wxString& msg)
+{
+#if wxDEBUG_LEVEL
+ // under GTK2 we prefer to use a dialog widget written using directly in
+ // GTK+ as use a dialog written using wxWidgets would need the wxWidgets
+ // idle processing to work correctly which might not be the case when
+ // assert happens
+ GtkWidget *dialog = gtk_assert_dialog_new();
+ gtk_assert_dialog_set_message(GTK_ASSERT_DIALOG(dialog), msg.mb_str());
+
+#if wxUSE_STACKWALKER
+ // don't show more than maxLines or we could get a dialog too tall to be
+ // shown on screen: 20 should be ok everywhere as even with 15 pixel high
+ // characters it is still only 300 pixels...
+ static const int maxLines = 20;
+
+ // save current stack frame...
+ StackDump dump(GTK_ASSERT_DIALOG(dialog));
+ dump.SaveStack(maxLines);
+
+ // ...but process it only if the user needs it
+ gtk_assert_dialog_set_backtrace_callback(GTK_ASSERT_DIALOG(dialog),
+ (GtkAssertDialogStackFrameCallback)get_stackframe_callback,
+ &dump);
+#endif // wxUSE_STACKWALKER
+
+ gint result = gtk_dialog_run(GTK_DIALOG (dialog));
+ bool returnCode = false;
+ switch (result)