error: The function/method "takes_an_immutable_reference" doesn't need a mutable reference
  --> mut_reference.rs:22:34
   |
22 |     takes_an_immutable_reference(&mut 42);
   |                                  ^^^^^^^
   |
   = note: `-D unnecessary-mut-passed` implied by `-D warnings`

error: The function/method "as_ptr" doesn't need a mutable reference
  --> mut_reference.rs:24:12
   |
24 |     as_ptr(&mut 42);
   |            ^^^^^^^
   |
   = note: `-D unnecessary-mut-passed` implied by `-D warnings`

error: The function/method "takes_an_immutable_reference" doesn't need a mutable reference
  --> mut_reference.rs:28:44
   |
28 |     my_struct.takes_an_immutable_reference(&mut 42);
   |                                            ^^^^^^^
   |
   = note: `-D unnecessary-mut-passed` implied by `-D warnings`

error: aborting due to previous error(s)

error: Could not compile `clippy_tests`.

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