diff --git a/tests/interactive/test-cogl-material.c b/tests/interactive/test-cogl-material.c
index 00084b568..8d6bdf3fe 100644
--- a/tests/interactive/test-cogl-material.c
+++ b/tests/interactive/test-cogl-material.c
@@ -39,7 +39,7 @@ frame_cb (ClutterTimeline  *timeline,
   cogl_material_set_layer_matrix (state->material, 2, &state->tex_matrix);
 }
 
-static gboolean
+static void
 material_rectangle_paint (ClutterActor *actor, gpointer data)
 {
   TestMultiLayerMaterialState *state = data;