{"ast_node_type":"other","tokens":[{"end":77,"kind":"keyword","start":0,"text":"//"}]}
        // We checked the root's signature during wfcheck, but not the child.
    for (idx, (param_ty, param)) in inputs_fn.chain(maybe_va_list).zip(body.params).enumerate() {
        if fcx.tcx.is_typeck_child(fn_def_id.to_def_id()) {