diff --git a/gtk/gtkmodelbutton.c b/gtk/gtkmodelbutton.c
index 67458d406d..467928a083 100644
--- a/gtk/gtkmodelbutton.c
+++ b/gtk/gtkmodelbutton.c
@@ -528,7 +528,8 @@ gtk_model_button_get_property (GObject    *object,
       break;
 
     default:
-      g_assert_not_reached ();
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
     }
 }
 
@@ -575,7 +576,8 @@ gtk_model_button_set_property (GObject      *object,
       break;
 
     default:
-      g_assert_not_reached ();
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
     }
 }