diff --git a/src/highlighters.cc b/src/highlighters.cc
index 468f263e..000befef 100644
--- a/src/highlighters.cc
+++ b/src/highlighters.cc
@@ -1029,7 +1029,7 @@ struct ShowWhitespacesHighlighter : Highlighter
     }
 
 private:
-    void do_highlight(HighlightContext context, DisplayBuffer& display_buffer, BufferRange)
+    void do_highlight(HighlightContext context, DisplayBuffer& display_buffer, BufferRange) override
     {
         const int tabstop = context.context.options()["tabstop"].get<int>();
         auto whitespaceface = context.context.faces()["Whitespace"];
diff --git a/src/scope.hh b/src/scope.hh
index e29a3c94..870e1159 100644
--- a/src/scope.hh
+++ b/src/scope.hh
@@ -57,7 +57,7 @@ class GlobalScope : public Scope, public OptionManagerWatcher, public Singleton<
         OptionsRegistry& option_registry() { return m_option_registry; }
         const OptionsRegistry& option_registry() const { return m_option_registry; }
     private:
-        void on_option_changed(const Option& option);
+        void on_option_changed(const Option& option) override;
 
         OptionsRegistry m_option_registry;
 };