let gui_toggle_slice_undef (main_ui:Design.main_window_extension_points) =
let slice_undef = not (SlicingParameters.Mode.SliceUndef.get ()) in
gui_apply_action main_ui SlicingParameters.Mode.SliceUndef.set slice_undef
~info:(fun () ->
if slice_undef then (get_setting_option_text "-slice-undef-functions" )^
". Allow the use of the slicing level for calls to undefined functions"
else (get_setting_option_text "-no-slice-undef-functions") ^
". Forbid the slicing of prototypes of undefined functions")