diff --git a/src/hotkeys.h b/src/hotkeys.h
--- a/src/hotkeys.h
+++ b/src/hotkeys.h
@@ -124,6 +124,8 @@ int CheckHotkeyMatch(Hotkey<T> *list, ui
 	return -1;
 }
 
+bool IsQuitKey(uint16 keycode);
+
 void LoadHotkeysFromConfig();
 void SaveHotkeysToConfig();