{"ast_node_type":"variable","tokens":[{"end":61,"kind":"keyword","start":0,"text":"let"}]}
            let val = CValue::by_val_pair(cb_out, c, layout);
            let layout = fx.layout_of(Ty::new_tup(fx.tcx, &[fx.tcx.types.u8, a.layout().ty]));
            ret.write_cvalue(fx, val);