diff --git a/test/cfoa/serialization_tests.cpp b/test/cfoa/serialization_tests.cpp
index ad762451..135567c5 100644
--- a/test/cfoa/serialization_tests.cpp
+++ b/test/cfoa/serialization_tests.cpp
@@ -11,6 +11,7 @@
 #include <boost/archive/xml_iarchive.hpp>
 #include <boost/serialization/nvp.hpp>
 #include <boost/unordered/concurrent_flat_map.hpp>
+#include <boost/unordered/concurrent_flat_set.hpp>
 
 namespace {
 
@@ -69,9 +70,11 @@ namespace {
 
   boost::concurrent_flat_map<
     test::object, test::object, test::hash, test::equal_to>* test_flat_map;
+  boost::concurrent_flat_set<
+    test::object, test::hash, test::equal_to>* test_flat_set;
 
   UNORDERED_TEST(serialization_tests,
-    ((test_flat_map))
+    ((test_flat_map)(test_flat_set))
     ((text_archive)(xml_archive))
     ((default_generator)))
 }