diff --git a/src/frontends/qt/Menus.cpp b/src/frontends/qt/Menus.cpp
index 5c096d0a8a..3a4facd441 100644
--- a/src/frontends/qt/Menus.cpp
+++ b/src/frontends/qt/Menus.cpp
@@ -289,7 +289,7 @@ public:
 	/// set the description of the  submenu
 	void submenuname(QString const & name) { submenuname_ = name; }
 	///
-	bool hasSubmenu() const { return !submenu_.isEmpty(); }
+	bool hasSubmenu() const;
 	///
 	MenuDefinition const & submenu() const { return submenu_.at(0); }
 	MenuDefinition & submenu() { return submenu_[0]; }
@@ -401,6 +401,9 @@ public:
 };
 
 
+bool MenuItem::hasSubmenu() const { return !submenu_.isEmpty(); }
+
+
 /// Helper for std::find_if
 class MenuNamesEqual
 {