--- old/src/hotspot/share/gc/shenandoah/shenandoahRootVerifier.hpp	2019-06-18 13:08:47.706212171 -0400
+++ new/src/hotspot/share/gc/shenandoah/shenandoahRootVerifier.hpp	2019-06-18 13:08:47.387211809 -0400
@@ -52,6 +52,8 @@
   // Used to seed ShenandoahVerifier, do not honor root type filter
   void roots_do(OopClosure* cl);
   void strong_roots_do(OopClosure* cl);
+
+  static RootTypes combine(RootTypes t1, RootTypes t2);
 private:
   bool verify(RootTypes type) const;
 };