v0.2.55..v0.2.56 changeset AddRef1Visitor.h

diff --git a/hoot-core/src/main/cpp/hoot/core/visitors/AddRef1Visitor.h b/hoot-core/src/main/cpp/hoot/core/visitors/AddRef1Visitor.h
index db51ddd..e435166 100644
--- a/hoot-core/src/main/cpp/hoot/core/visitors/AddRef1Visitor.h
+++ b/hoot-core/src/main/cpp/hoot/core/visitors/AddRef1Visitor.h
@@ -41,6 +41,7 @@ public:
   static std::string className() { return "hoot::AddRef1Visitor"; }
 
   AddRef1Visitor();
+  virtual ~AddRef1Visitor() = default;
 
   virtual void setConfiguration(const Settings& conf);