diff --git a/furc/include/furc/ast/visitor.hpp b/furc/include/furc/ast/visitor.hpp
index 32cc2a8..8123c0f 100644
--- a/furc/include/furc/ast/visitor.hpp
+++ b/furc/include/furc/ast/visitor.hpp
@@ -8,6 +8,7 @@ namespace ast {
 
 class visitor {
 public:
+    visitor()          = default;
     virtual ~visitor() = default;
 
     visitor(visitor&&)                 = default;