error: generally you want to avoid `&mut &mut _` if possible
  --> $DIR/mut_mut.rs:4:11
   |
LL | fn fun(x: &mut &mut u32) -> bool {
   |           ^^^^^^^^^^^^^
   |
   = note: `-D clippy::mut-mut` implied by `-D warnings`

error: generally you want to avoid `&mut &mut _` if possible
  --> $DIR/mut_mut.rs:20:17
   |
LL |     let mut x = &mut &mut 1u32;
   |                 ^^^^^^^^^^^^^^

error: generally you want to avoid `&mut &mut _` if possible
  --> $DIR/mut_mut.rs:14:9
   |
LL |         &mut $p
   |         ^^^^^^^
...
LL |     let mut z = mut_ptr!(&mut 3u32);
   |                 ------------------- in this macro invocation
   |
   = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)

error: this expression mutably borrows a mutable reference. Consider reborrowing
  --> $DIR/mut_mut.rs:22:21
   |
LL |         let mut y = &mut x;
   |                     ^^^^^^

error: generally you want to avoid `&mut &mut _` if possible
  --> $DIR/mut_mut.rs:26:32
   |
LL |         let y: &mut &mut u32 = &mut &mut 2;
   |                                ^^^^^^^^^^^

error: generally you want to avoid `&mut &mut _` if possible
  --> $DIR/mut_mut.rs:26:16
   |
LL |         let y: &mut &mut u32 = &mut &mut 2;
   |                ^^^^^^^^^^^^^

error: generally you want to avoid `&mut &mut _` if possible
  --> $DIR/mut_mut.rs:31:37
   |
LL |         let y: &mut &mut &mut u32 = &mut &mut &mut 2;
   |                                     ^^^^^^^^^^^^^^^^

error: generally you want to avoid `&mut &mut _` if possible
  --> $DIR/mut_mut.rs:31:16
   |
LL |         let y: &mut &mut &mut u32 = &mut &mut &mut 2;
   |                ^^^^^^^^^^^^^^^^^^

error: generally you want to avoid `&mut &mut _` if possible
  --> $DIR/mut_mut.rs:31:21
   |
LL |         let y: &mut &mut &mut u32 = &mut &mut &mut 2;
   |                     ^^^^^^^^^^^^^

error: aborting due to 9 previous errors