{"ast_node_type":"variable","tokens":[{"end":64,"kind":"keyword","start":0,"text":"let"}]}
    let end_col_has_high_bit_unset = (end_col & (1 << 31)) == 0;
    // region is actually a "gap" region, so make sure it's unset.
    // If a region is improperly ordered (end < start), `llvm-cov` will exit