[gtk+] tests: Make forcing of class registers work without gcc warnings

[Benjamin Otte <otte src gnome org>]

commit 8c4653c4f2186d6c841d87db1f129455ab0374e8
Author: Benjamin Otte <otte redhat com>
Date:   Fri May 27 04:20:45 2011 +0200

    tests: Make forcing of class registers work without gcc warnings

 tests/testtreeview.c |   16 +++++++---------
 1 files changed, 7 insertions(+), 9 deletions(-)
---
diff --git a/tests/testtreeview.c b/tests/testtreeview.c
index 80efc90..312b4ec 100644
--- a/tests/testtreeview.c
+++ b/tests/testtreeview.c
@@ -626,17 +626,15 @@ create_tree_model (void)
   GtkTreeStore *store;
   gint i;
   GType *t;
-  volatile GType dummy; /* G_GNUC_CONST makes the optimizer remove
-                         * get_type calls if you don't do something
-                         * like this
-                         */
   
   /* Make the tree more interesting */
-  dummy = gtk_scrolled_window_get_type ();
-  dummy = gtk_label_get_type ();
-  dummy = gtk_hscrollbar_get_type ();
-  dummy = gtk_vscrollbar_get_type ();
-  dummy = pango_layout_get_type ();
+  /* - we need this magic here so we are sure the type ends up being
+   * registered and gcc doesn't optimize away the code */
+  g_type_class_unref (g_type_class_ref (gtk_scrolled_window_get_type ()));
+  g_type_class_unref (g_type_class_ref (gtk_label_get_type ()));
+  g_type_class_unref (g_type_class_ref (gtk_hscrollbar_get_type ()));
+  g_type_class_unref (g_type_class_ref (gtk_vscrollbar_get_type ()));
+  g_type_class_unref (g_type_class_ref (pango_layout_get_type ()));
 
   t = get_model_types ();