diff -u b/core/lib/Drupal/Core/Entity/FieldableDatabaseStorageController.php b/core/lib/Drupal/Core/Entity/FieldableDatabaseStorageController.php
--- b/core/lib/Drupal/Core/Entity/FieldableDatabaseStorageController.php
+++ b/core/lib/Drupal/Core/Entity/FieldableDatabaseStorageController.php
@@ -309,7 +309,7 @@
     return $entities;
   }
 
-  protected function loadMultipleFromCache($ids) {
+  protected function loadMultipleFromCache(&$ids) {
     if (!$this->persistentCache) {
       return array();
     }