diff --git a/src/debugger/gui/CartELFWidget.hxx b/src/debugger/gui/CartELFWidget.hxx
index c9743f11a..e35f47120 100644
--- a/src/debugger/gui/CartELFWidget.hxx
+++ b/src/debugger/gui/CartELFWidget.hxx
@@ -34,6 +34,11 @@ class CartridgeELFWidget: public CartDebugWidget
 
     ~CartridgeELFWidget() override = default;
 
+private:
+  enum {
+    kSaveArmImageCmd = 'sarm'
+  };
+
   private:
     void initialize();
     void saveArmImage(const FSNode& node);