diff --git a/dlib/gui_widgets/fonts_abstract.h b/dlib/gui_widgets/fonts_abstract.h
index db89dfaed..5248ca9c9 100644
--- a/dlib/gui_widgets/fonts_abstract.h
+++ b/dlib/gui_widgets/fonts_abstract.h
@@ -479,7 +479,7 @@ namespace dlib
 
 // ----------------------------------------------------------------------------------------
 
-    font* get_native_font (
+    const font* get_native_font (
     );
     /*!
         ensures