v0.2.55..v0.2.56 changeset ChainCriterion.h

diff --git a/hoot-core/src/main/cpp/hoot/core/criterion/ChainCriterion.h b/hoot-core/src/main/cpp/hoot/core/criterion/ChainCriterion.h
index 0a0a533..4ec67f5 100644
--- a/hoot-core/src/main/cpp/hoot/core/criterion/ChainCriterion.h
+++ b/hoot-core/src/main/cpp/hoot/core/criterion/ChainCriterion.h
@@ -45,11 +45,12 @@ public:
 
   static std::string className() { return "hoot::ChainCriterion"; }
 
-  ChainCriterion() {}
+  ChainCriterion() = default;
   ChainCriterion(const ElementCriterionPtr& child1, const ElementCriterionPtr& child2);
   ChainCriterion(ElementCriterion* child1, ElementCriterion* child2);
   ChainCriterion(ElementCriterion* child1, ElementCriterionPtr child2);
   ChainCriterion(ElementCriterion* child1, ElementCriterion* child2, ElementCriterion* child3);
+  virtual ~ChainCriterion() = default;
 
   virtual void addCriterion(const ElementCriterionPtr& e);