| error[E0596]: cannot borrow `*x.1` as mutable, as it is behind a `&` reference | |
| --> $DIR/issue-61623.rs:6:19 | |
| | | |
| LL | f2(|| x.0, f1(x.1)) | |
| | ^^^ `x` is a `&` reference, so the data it refers to cannot be borrowed as mutable | |
| | | |
| help: consider changing this to be a mutable reference | |
| | | |
| LL | fn f3<'a>(x: &'a mut ((), &'a mut ())) { | |
| | +++ | |
| error: aborting due to 1 previous error | |
| For more information about this error, try `rustc --explain E0596`. |