--- a/src/hotspot/share/oops/symbol.cpp	Fri May 17 10:48:02 2019 -0400
+++ b/src/hotspot/share/oops/symbol.cpp	Fri May 17 08:29:55 2019 -0700
@@ -74,6 +74,13 @@
   FreeHeap(p);
 }
 
+void Symbol::set_permanent() {
+  // This is called at a safepoint during dumping of a dynamic CDS archive.
+  assert(SafepointSynchronize::is_at_safepoint(), "must be at a safepoint");
+  _length_and_refcount =  pack_length_and_refcount(length(), PERM_REFCOUNT);
+}
+
+
 // ------------------------------------------------------------------
 // Symbol::starts_with
 //