diff --git a/includes/bootstrap.inc b/includes/bootstrap.inc
index 46baf3cff5..9ee661f742 100644
--- a/includes/bootstrap.inc
+++ b/includes/bootstrap.inc
@@ -3775,9 +3775,11 @@ function _drupal_shutdown_function() {
   // was in the normal context of execution.
   chdir(DRUPAL_ROOT);
 
+  reset($callbacks);
   try {
-    foreach ($callbacks as $callback) {
+    while ($callback = current($callbacks)) {
       call_user_func_array($callback['callback'], $callback['arguments']);
+      next($callbacks);
     }
   }
   catch (Exception $exception) {