--- a/src/hotspot/share/classfile/systemDictionary.cpp	Fri Aug 24 11:56:14 2018 -0700
+++ b/src/hotspot/share/classfile/systemDictionary.cpp	Fri Aug 24 15:33:28 2018 -0400
@@ -1160,10 +1160,12 @@
 #if INCLUDE_CDS
 void SystemDictionary::set_shared_dictionary(HashtableBucket<mtClass>* t, int length,
                                              int number_of_entries) {
+  assert(!DumpSharedSpaces, "Should not be called with DumpSharedSpaces");
   assert(length == _shared_dictionary_size * sizeof(HashtableBucket<mtClass>),
          "bad shared dictionary size.");
   _shared_dictionary = new Dictionary(ClassLoaderData::the_null_class_loader_data(),
-                                      _shared_dictionary_size, t, number_of_entries);
+                                      _shared_dictionary_size, t, number_of_entries,
+                                      false /* explicitly set _resizable to false */);
 }