{"ast_node_type":"variable","tokens":[{"end":21,"kind":"keyword","start":0,"text":"let"}]}
    let mut root_cx =
) -> FxHashMap<LocalDefId, BodyWithBorrowckFacts<'_>> {
        BorrowCheckRootCtxt::new(tcx, root_def_id, Some(BorrowckConsumer::new(options)));