error[E0503]: cannot use `value` because it was mutably borrowed --> $DIR/E0503.rs:4:16 | LL | let _borrow = &mut value; | ---------- `value` is borrowed here LL | let _sum = value + 1; | ^^^^^ use of borrowed `value` LL | _borrow.use_mut(); | ------- borrow later used here error: aborting due to previous error For more information about this error, try `rustc --explain E0503`.