error[E0626]: borrow may still be in use when coroutine yields
  --> $DIR/yield-while-iterating.rs:13:18
   |
LL |         for p in &x {
   |                  ^^
LL |             yield();
   |             ------- possible yield occurs here

error[E0502]: cannot borrow `x` as immutable because it is also borrowed as mutable
  --> $DIR/yield-while-iterating.rs:58:20
   |
LL |     let mut b = || {
   |                 -- mutable borrow occurs here
LL |         for p in &mut x {
   |                       - first borrow occurs due to use of `x` in coroutine
...
LL |     println!("{}", x[0]);
   |                    ^ immutable borrow occurs here
LL |     Pin::new(&mut b).resume(());
   |              ------ mutable borrow later used here

error: aborting due to 2 previous errors

Some errors have detailed explanations: E0502, E0626.
For more information about an error, try `rustc --explain E0502`.