--- a/libinterp/dldfcn/__init_fltk__.cc	Wed Jun 09 09:14:43 2021 -0400
+++ b/libinterp/dldfcn/__init_fltk__.cc	Fri Jun 11 09:23:33 2021 -0400
@@ -2484,27 +2484,25 @@
 
 #endif
 
-// This function has the same type signature as a builtin function so
-// that we can create a function handle from it but it is not defined
-// using a DEFMETHOD macro so that it will be omitted from the list of
-// autoloaded functions in the PKG_ADD file and will not be visible to
-// the interpreter.
-
+DEFMETHOD_DLD (__fltk_check__, interp, , ,
+               doc: /* -*- texinfo -*-
+@deftypefn {} {} __fltk_check__ ()
+Undocumented internal function.  Calls Fl::check ()
+@end deftypefn */)
+{
 #if defined (HAVE_FLTK)
-static octave_value_list
-F__fltk_check__ (octave::interpreter& interp, const octave_value_list&, int)
-{
   Fl::check ();
 
   if (Vdrawnow_requested)
     Fdrawnow (interp);
 
   return octave_value_list ();
+#else
   octave_unused_parameter (interp);
 
   err_disabled_feature ("__fltk_check__", "OpenGL and FLTK");
+#endif
 }
-#endif
 
 // Initialize the fltk graphics toolkit.