diff --git a/clutter/clutter-alpha.c b/clutter/clutter-alpha.c
index 7b8d34cbe..c25a4b27f 100644
--- a/clutter/clutter-alpha.c
+++ b/clutter/clutter-alpha.c
@@ -743,7 +743,7 @@ clutter_square_func (ClutterAlpha *alpha,
  */
 guint32
 clutter_smoothstep_inc_func (ClutterAlpha  *alpha,
-			     gpointer      *dummy)
+			     gpointer       dummy)
 {
   ClutterTimeline    *timeline;
   gint                frame;
@@ -790,7 +790,7 @@ clutter_smoothstep_inc_func (ClutterAlpha  *alpha,
  */
 guint32
 clutter_smoothstep_dec_func (ClutterAlpha  *alpha,
-			     gpointer      *dummy)
+			     gpointer       dummy)
 {
   return CLUTTER_ALPHA_MAX_ALPHA - clutter_smoothstep_inc_func (alpha, dummy);
 }
diff --git a/clutter/clutter-alpha.h b/clutter/clutter-alpha.h
index 6af270098..8c3bbd259 100644
--- a/clutter/clutter-alpha.h
+++ b/clutter/clutter-alpha.h
@@ -134,9 +134,9 @@ guint32             clutter_sine_half_func      (ClutterAlpha     *alpha,
 guint32             clutter_square_func         (ClutterAlpha     *alpha,
 						 gpointer          dummy);
 guint32             clutter_smoothstep_inc_func (ClutterAlpha     *alpha,
-			                         gpointer         *data);
+			                         gpointer          dummy);
 guint32             clutter_smoothstep_dec_func (ClutterAlpha     *alpha,
-			                         gpointer         *data);
+			                         gpointer          dummy);
 guint32             clutter_exp_inc_func        (ClutterAlpha     *alpha,
 						 gpointer          dummy);
 guint32             clutter_exp_dec_func        (ClutterAlpha     *alpha,