{"ast_node_type":"function","tokens":[{"end":84,"kind":"keyword","start":0,"text":"fn"}]}
fn dump_abi_of_fn_type(tcx: TyCtxt<'_>, item_def_id: LocalDefId, attr: &Attribute) {
    let typing_env = ty::TypingEnv::post_analysis(tcx, item_def_id);