error[E0495]: cannot infer an appropriate lifetime due to conflicting requirements
  --> $DIR/regions-nested-fns.rs:5:18
   |
LL |     let mut ay = &y;
   |                  ^^
   |
note: first, the lifetime cannot outlive the anonymous lifetime #2 defined on the body at 7:58...
  --> $DIR/regions-nested-fns.rs:7:58
   |
LL |       ignore::<Box<dyn for<'z> FnMut(&'z isize)>>(Box::new(|z| {
   |  __________________________________________________________^
LL | |         ay = x;
LL | |         ay = &y;
LL | |         ay = z;
LL | |     }));
   | |_____^
note: ...so that reference does not outlive borrowed content
  --> $DIR/regions-nested-fns.rs:10:14
   |
LL |         ay = z;
   |              ^
note: but, the lifetime must be valid for the anonymous lifetime #2 defined on the body at 13:72...
  --> $DIR/regions-nested-fns.rs:13:72
   |
LL |       ignore::< Box<dyn for<'z> FnMut(&'z isize) -> &'z isize>>(Box::new(|z| {
   |  ________________________________________________________________________^
LL | |         if false { return x; }
LL | |         if false { return ay; }
LL | |         return z;
LL | |     }));
   | |_____^
   = note: ...so that the types are compatible:
           expected &isize
              found &isize

error[E0312]: lifetime of reference outlives lifetime of borrowed content...
  --> $DIR/regions-nested-fns.rs:14:27
   |
LL |         if false { return x; }
   |                           ^
   |
note: ...the reference is valid for the anonymous lifetime #2 defined on the body at 13:72...
  --> $DIR/regions-nested-fns.rs:13:72
   |
LL |       ignore::< Box<dyn for<'z> FnMut(&'z isize) -> &'z isize>>(Box::new(|z| {
   |  ________________________________________________________________________^
LL | |         if false { return x; }
LL | |         if false { return ay; }
LL | |         return z;
LL | |     }));
   | |_____^
note: ...but the borrowed content is only valid for the lifetime `'x` as defined on the function body at 3:11
  --> $DIR/regions-nested-fns.rs:3:11
   |
LL | fn nested<'x>(x: &'x isize) {
   |           ^^

error: aborting due to 2 previous errors

Some errors have detailed explanations: E0312, E0495.
For more information about an error, try `rustc --explain E0312`.