diff --git a/clang-tools-extra/clangd/AST.cpp b/clang-tools-extra/clangd/AST.cpp
--- a/clang-tools-extra/clangd/AST.cpp
+++ b/clang-tools-extra/clangd/AST.cpp
@@ -310,7 +310,7 @@
   public:
     PrintCB(const DeclContext *CurContext) : CurContext(CurContext) {}
     virtual ~PrintCB() {}
-    virtual bool isScopeVisible(const DeclContext *DC) const {
+    virtual bool isScopeVisible(const DeclContext *DC) const override {
       return DC->Encloses(CurContext);
     }