{"ast_node_type":"variable","tokens":[{"end":91,"kind":"keyword","start":0,"text":"let"}]}
    let covfun_var_name = CString::new(format!("__covrec_{func_name_hash:X}{u}")).unwrap();
    let u = if is_used { "u" } else { "" };
    debug!("function record var name: {covfun_var_name:?}");