diff --git a/src/backends/meta-backend-private.h b/src/backends/meta-backend-private.h
index 9d88d8a58..00ec8ba6a 100644
--- a/src/backends/meta-backend-private.h
+++ b/src/backends/meta-backend-private.h
@@ -162,9 +162,6 @@ xkb_layout_index_t meta_backend_get_keymap_layout_group (MetaBackend *backend);
 
 gboolean meta_backend_is_lid_closed (MetaBackend *backend);
 
-void meta_backend_update_last_device (MetaBackend        *backend,
-                                      ClutterInputDevice *device);
-
 MetaPointerConstraint * meta_backend_get_client_pointer_constraint (MetaBackend *backend);
 void meta_backend_set_client_pointer_constraint (MetaBackend *backend,
                                                  MetaPointerConstraint *constraint);
diff --git a/src/backends/meta-backend.c b/src/backends/meta-backend.c
index 1837bb211..f5b54dc23 100644
--- a/src/backends/meta-backend.c
+++ b/src/backends/meta-backend.c
@@ -381,7 +381,7 @@ update_last_device (MetaBackend *backend)
   return G_SOURCE_REMOVE;
 }
 
-void
+static void
 meta_backend_update_last_device (MetaBackend        *backend,
                                  ClutterInputDevice *device)
 {