diff --git a/cogl/cogl-onscreen.c b/cogl/cogl-onscreen.c
index a7a958f29..4768509b8 100644
--- a/cogl/cogl-onscreen.c
+++ b/cogl/cogl-onscreen.c
@@ -52,6 +52,29 @@ COGL_OBJECT_DEFINE_WITH_CODE_GTYPE (Onscreen, onscreen,
 COGL_GTYPE_DEFINE_CLASS (Onscreen, onscreen,
                          COGL_GTYPE_IMPLEMENT_INTERFACE (framebuffer));
 
+static gpointer
+cogl_dummy_copy (gpointer data)
+{
+  return data;
+}
+
+static void
+cogl_dummy_free (gpointer data)
+{
+}
+
+COGL_GTYPE_DEFINE_BOXED (FrameClosure, frame_closure,
+                         cogl_dummy_copy,
+                         cogl_dummy_free);
+COGL_GTYPE_DEFINE_BOXED (OnscreenResizeClosure,
+                         onscreen_resize_closure,
+                         cogl_dummy_copy,
+                         cogl_dummy_free);
+COGL_GTYPE_DEFINE_BOXED (OnscreenDirtyClosure,
+                         onscreen_dirty_closure,
+                         cogl_dummy_copy,
+                         cogl_dummy_free);
+
 static void
 _cogl_onscreen_init_from_template (CoglOnscreen *onscreen,
                                    CoglOnscreenTemplate *onscreen_template)
diff --git a/cogl/cogl-onscreen.h b/cogl/cogl-onscreen.h
index fd24e129f..0edae921d 100644
--- a/cogl/cogl-onscreen.h
+++ b/cogl/cogl-onscreen.h
@@ -570,6 +570,15 @@ typedef void (*CoglFrameCallback) (CoglOnscreen *onscreen,
  */
 typedef struct _CoglClosure CoglFrameClosure;
 
+#ifdef COGL_HAS_GTYPE_SUPPORT
+/**
+ * cogl_frame_closure_get_gtype:
+ *
+ * Returns: a #GType that can be used with the GLib type system.
+ */
+GType cogl_frame_closure_get_gtype (void);
+#endif
+
 /**
  * cogl_onscreen_add_frame_callback:
  * @onscreen: A #CoglOnscreen framebuffer
@@ -788,6 +797,15 @@ typedef void (*CoglOnscreenResizeCallback) (CoglOnscreen *onscreen,
  */
 typedef struct _CoglClosure CoglOnscreenResizeClosure;
 
+#ifdef COGL_HAS_GTYPE_SUPPORT
+/**
+ * cogl_onscreen_resize_closure_get_gtype:
+ *
+ * Returns: a #GType that can be used with the GLib type system.
+ */
+GType cogl_onscreen_resize_closure_get_gtype (void);
+#endif
+
 /**
  * cogl_onscreen_add_resize_callback:
  * @onscreen: A #CoglOnscreen framebuffer
@@ -895,6 +913,15 @@ typedef void (*CoglOnscreenDirtyCallback) (CoglOnscreen *onscreen,
  */
 typedef struct _CoglClosure CoglOnscreenDirtyClosure;
 
+#ifdef COGL_HAS_GTYPE_SUPPORT
+/**
+ * cogl_onscreen_dirty_closure_get_gtype:
+ *
+ * Returns: a #GType that can be used with the GLib type system.
+ */
+GType cogl_onscreen_dirty_closure_get_gtype (void);
+#endif
+
 /**
  * cogl_onscreen_add_dirty_callback:
  * @onscreen: A #CoglOnscreen framebuffer