src/test/ui/regions/regions-return-ref-to-upvar-issue-17403.nll.stderr

warning: not reporting region error due to nll
  --> $DIR/regions-return-ref-to-upvar-issue-17403.rs:17:24
   |
LL |         let mut f = || &mut x; //~ ERROR cannot infer
   |                        ^^^^^^

error: unsatisfied lifetime constraints
  --> $DIR/regions-return-ref-to-upvar-issue-17403.rs:17:24
   |
LL |         let mut f = || &mut x; //~ ERROR cannot infer
   |                     -- ^^^^^^ returning this value requires that `'1` must outlive `'2`
   |                     ||
   |                     |return type of closure is &'2 mut i32
   |                     lifetime `'1` represents this closure's body
   |
   = note: closure implements `FnMut`, so references to captured variables can't escape the closure

error: aborting due to previous error