Simplify union_abstract_objectt::write_component

Author: jezhiggins

src/analyses/variable-sensitivity/union_abstract_object.cpp

@@ -65,7 +65,7 @@ abstract_object_pointert union_abstract_objectt::read_component(
     member_expr.type(), ns, !is_bottom(), is_bottom());
 }
 
-sharing_ptrt<union_abstract_objectt> union_abstract_objectt::write_component(
+abstract_object_pointert union_abstract_objectt::write_component(
   abstract_environmentt &environment,
   const namespacet &ns,
   const std::stack<exprt> &stack,
@@ -75,11 +75,10 @@ sharing_ptrt<union_abstract_objectt> union_abstract_objectt::write_component(
 {
   if(is_top() || is_bottom())
   {
-    return std::dynamic_pointer_cast<const union_abstract_objectt>(clone());
+    return shared_from_this();
   }
   else
   {
-    return sharing_ptrt<union_abstract_objectt>(
-      new union_abstract_objectt(type(), true, false));
+    return std::make_shared<union_abstract_objectt>(type(), true, false);
   }
 }

src/analyses/variable-sensitivity/union_abstract_object.h

@@ -118,7 +118,7 @@ class union_abstract_objectt : public abstract_objectt
   /// \return The union_abstract_objectt representing the result of writing
   ///         to a specific component. In this case this will always be top
   ///         as we are not tracking the value of this union.
-  virtual sharing_ptrt<union_abstract_objectt> write_component(
+  virtual abstract_object_pointert write_component(
     abstract_environmentt &environment,
     const namespacet &ns,
     const std::stack<exprt> &stack,