{"ast_node_type":"variable","tokens":[{"end":43,"kind":"keyword","start":0,"text":"let"}]}
    let u = if is_used { "u" } else { "" };
    // linker sees both it won't discard the used copy's data.
    let covfun_var_name = CString::new(format!("__covrec_{func_name_hash:X}{u}")).unwrap();