diff --git a/include/swift/Demangling/Demangle.h b/include/swift/Demangling/Demangle.h
index edb6591c708e2..259217fd01924 100644
--- a/include/swift/Demangling/Demangle.h
+++ b/include/swift/Demangling/Demangle.h
@@ -871,7 +871,7 @@ class NodePrinter {
 
   virtual ~NodePrinter() = default;
 
-  void printRoot(NodePointer root) {
+  virtual void printRoot(NodePointer root) {
     isValid = true;
     print(root, 0);
   }