diff --git a/core/Controller/LoginController.php b/core/Controller/LoginController.php
index ffa5b10fc2ff7cd2734a4c17e1746ca8c1964d82..2235439d9568d5941e114a70449d6b98a2d2b9b3 100644
--- a/core/Controller/LoginController.php
+++ b/core/Controller/LoginController.php
@@ -141,7 +141,8 @@ class LoginController extends Controller {
 	 *
 	 * @return TemplateResponse|RedirectResponse
 	 */
-	public function showLoginForm($user, $redirect_url) {
+	public function showLoginForm(string $user = null, string $redirect_url = null): Http\Response {
+
 		if ($this->userSession->isLoggedIn()) {
 			return new RedirectResponse(OC_Util::getDefaultPageUrl());
 		}