--- a/src/hotspot/share/gc/parallel/pcTasks.cpp	Tue Aug 21 13:12:15 2018 +0200
+++ b/src/hotspot/share/gc/parallel/pcTasks.cpp	Tue Aug 21 09:33:41 2018 -0400
@@ -107,8 +107,10 @@
       SystemDictionary::oops_do(&mark_and_push_closure);
       break;
 
-    case class_loader_data:
-      ClassLoaderDataGraph::always_strong_oops_do(&mark_and_push_closure, true);
+    case class_loader_data: {
+        CLDToOopClosure cld_closure(&mark_and_push_closure);
+        ClassLoaderDataGraph::always_strong_cld_do(&cld_closure);
+      }
       break;
 
     case code_cache: