diff --git a/gnl/gnlcomposition.c b/gnl/gnlcomposition.c
index 88eafd95d4..b99b805ded 100644
--- a/gnl/gnlcomposition.c
+++ b/gnl/gnlcomposition.c
@@ -637,6 +637,8 @@ gnl_composition_finalize (GObject * object)
   g_rec_mutex_clear (&comp->task_rec_lock);
 
   G_OBJECT_CLASS (parent_class)->finalize (object);
+
+  g_mutex_clear (&priv->mcontext_lock);
 }
 
 static void