error: needlessly taken reference of both operands
  --> $DIR/op_ref.rs:11:15
   |
LL |     let foo = &5 - &6;
   |               ^^^^^^^
   |
   = note: `-D clippy::op-ref` implied by `-D warnings`
help: use the values directly
   |
LL |     let foo = 5 - 6;
   |               ~   ~

error: taken reference of right operand
  --> $DIR/op_ref.rs:56:13
   |
LL |     let z = x & &y;
   |             ^^^^--
   |                 |
   |                 help: use the right value directly: `y`

error: aborting due to 2 previous errors