in libdbusmenu-glib/menuitem-marshal.c [180:197]
typedef gboolean (*GMarshalFunc_BOOLEAN__STRING_VARIANT_UINT) (gpointer data1,
gpointer arg_1,
gpointer arg_2,
guint arg_3,
gpointer data2);
GMarshalFunc_BOOLEAN__STRING_VARIANT_UINT callback;
GCClosure *cc = (GCClosure*) closure;
gpointer data1, data2;
gboolean v_return;
g_return_if_fail (return_value != NULL);
g_return_if_fail (n_param_values == 4);
if (G_CCLOSURE_SWAP_DATA (closure))
{
data1 = closure->data;
data2 = g_value_peek_pointer (param_values + 0);
}