10 | fn fun(x : &mut &mut u32) -> bool {
| ^^^^^^^^^^^^^
|
-note: lint level defined here
- --> $DIR/mut_mut.rs:5:9
- |
-5 | #![deny(mut_mut)]
- | ^^^^^^^
+ = note: `-D mut-mut` implied by `-D warnings`
error: generally you want to avoid `&mut &mut _` if possible
--> $DIR/mut_mut.rs:24:17