error[E0502]: cannot borrow `p` as mutable because it is also borrowed as immutable
  --> $DIR/borrowck-assign-comp-idx.rs:22:5
   |
LL |     let q: &isize = &p[0];
   |                      - immutable borrow occurs here
LL | 
LL |     p[0] = 5; //~ ERROR cannot borrow
   |     ^ mutable borrow occurs here
LL | 
LL |     println!("{}", *q);
   |                    -- borrow later used here

error[E0502]: cannot borrow `p` as mutable because it is also borrowed as immutable
  --> $DIR/borrowck-assign-comp-idx.rs:37:9
   |
LL | /     borrow(
LL | |         &p,
   | |         -- immutable borrow occurs here
LL | |         || p[0] = 5); //~ ERROR cannot borrow `p` as mutable
   | |_________^^_-_______- borrow later used here
   |           |  |
   |           |  second borrow occurs due to use of `p` in closure
   |           mutable borrow occurs here

error: aborting due to 2 previous errors

For more information about this error, try `rustc --explain E0502`.