--- a/hotspot/src/share/vm/classfile/classLoaderData.cpp	Wed Jul 09 21:56:16 2014 +0000
+++ b/hotspot/src/share/vm/classfile/classLoaderData.cpp	Thu Jul 10 15:12:48 2014 +0200
@@ -717,11 +717,22 @@
   // unneeded entries.
   bool has_redefined_a_class = JvmtiExport::has_redefined_a_class();
   MetadataOnStackMark md_on_stack;
+  if (has_redefined_a_class) {
+    // purge_previous_versions also cleans weak method links. Because
+    // one method's MDO can reference another method from another
+    // class loader, we need to first clean weak method links for all
+    // class loaders here. Below, we can then free redefined methods
+    // for all class loaders.
+    while (data != NULL) {
+      if (data->is_alive(is_alive_closure)) {
+        data->classes_do(InstanceKlass::purge_previous_versions);
+      }
+      data = data->next();
+    }
+  }
+  data = _head;
   while (data != NULL) {
     if (data->is_alive(is_alive_closure)) {
-      if (has_redefined_a_class) {
-        data->classes_do(InstanceKlass::purge_previous_versions);
-      }
       data->free_deallocate_list();
       prev = data;
       data = data->next();