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 1 previous error

For more information about this error, try `rustc --explain E0503`.