-G_CONST_RETURN gchar* gtk_icon_source_get_filename (const GtkIconSource *source);
-G_CONST_RETURN gchar* gtk_icon_source_get_icon_name (const GtkIconSource *source);
-GdkPixbuf* gtk_icon_source_get_pixbuf (const GtkIconSource *source);
+const gchar * gtk_icon_source_get_filename (const GtkIconSource *source);
+const gchar * gtk_icon_source_get_icon_name (const GtkIconSource *source);
+GdkPixbuf* gtk_icon_source_get_pixbuf (const GtkIconSource *source);