error[E0597]: `short` does not live long enough
  --> $DIR/loan-extend.rs:21:1
   |
19 |     long = borrow(&mut short);
   |                        ----- borrow occurs here
20 |
21 | }
   | ^ `short` dropped here while still borrowed
   |
   = note: values in a scope are dropped in the opposite order they are created

error: aborting due to previous error

If you want more information on this error, try using "rustc --explain E0597"