GTK_TYPE_CONST_STRING?

[Murray Cumming <murrayc usa net>]

signal's whose default handlers take const gchar*, such as
GtkStatusBar's "text-pushed":

void	(*text_pushed)	(GtkStatusbar	*statusbar,
			 guint		 context_id,
			 const gchar	*text);

are registered as taking a regular GTK_TYPE_STRING, like so:
 
statusbar_signals[SIGNAL_TEXT_PUSHED] =
    gtk_signal_new ("text_pushed",
		    GTK_RUN_LAST,
		    GTK_CLASS_TYPE (object_class),
		    GTK_SIGNAL_OFFSET (GtkStatusbarClass, text_pushed),
		    gtk_marshal_VOID__UINT_STRING,
		    GTK_TYPE_NONE, 2,
		    GTK_TYPE_UINT,
		    GTK_TYPE_STRING);

How can my .defs generation code [1] discover that it's actually a const
gchar* that's wanted?

[1] http://cvs.gnome.org/lxr/source/gtkmm-root/tools/generate_extra_defs.cc

Murray Cumming
murrayc usa net
www.murrayc.com