Issue #2880387 by Kingdutch: Avoid unnecessary array operations in update_get_update_list

core/includes/update.inc

@@ -323,8 +323,7 @@ function update_get_update_list() {
         continue;
       }
 
-      $updates = array_combine($updates, $updates);
-      foreach (array_keys($updates) as $update) {
+      foreach ($updates as $update) {
         if ($update == \Drupal::CORE_MINIMUM_SCHEMA_VERSION) {
           $ret[$module]['warning'] = '<em>' . $module . '</em> module cannot be updated. It contains an update numbered as ' . \Drupal::CORE_MINIMUM_SCHEMA_VERSION . ' which is reserved for the earliest installation of a module in Drupal ' . \Drupal::CORE_COMPATIBILITY . ', before any updates. In order to update <em>' . $module . '</em> module, you will need to install a version of the module with valid updates.';
           continue 2;