diff -r 48a95b70d4af -r cdef4df6b0e7 src/hotspot/share/classfile/systemDictionary.cpp
--- a/src/hotspot/share/classfile/systemDictionary.cpp	Fri Aug 31 09:10:27 2018 -0400
+++ b/src/hotspot/share/classfile/systemDictionary.cpp	Fri Aug 31 10:22:04 2018 -0400
@@ -1884,7 +1884,7 @@
     // Oops referenced by the protection domain cache table may get unreachable independently
     // of the class loader (eg. cached protection domain oops). So we need to
     // explicitly unlink them here.
-    _pd_cache_table->unlink();
+    _pd_cache_table->trigger_cleanup();
   }
 
   if (do_cleaning) {