error: needlessly taken reference of both operands
  --> tests/ui/op_ref.rs:11:15
   |
LL |     let foo = &5 - &6;
   |               ^^^^^^^
   |
   = note: `-D clippy::op-ref` implied by `-D warnings`
   = help: to override `-D warnings` add `#[allow(clippy::op_ref)]`
help: use the values directly
   |
LL |     let foo = 5 - 6;
   |               ~   ~

error: taken reference of right operand
  --> tests/ui/op_ref.rs:58:13
   |
LL |     let z = x & &y;
   |             ^^^^--
   |                 |
   |                 help: use the right value directly: `y`

error: taken reference of right operand
  --> tests/ui/op_ref.rs:92:17
   |
LL |         let _ = one * &self;
   |                 ^^^^^^-----
   |                       |
   |                       help: use the right value directly: `self`

error: taken reference of right operand
  --> tests/ui/op_ref.rs:94:17
   |
LL |         let _ = two + &three;
   |                 ^^^^^^------
   |                       |
   |                       help: use the right value directly: `three`

error: aborting due to 4 previous errors