warning: assigning the result of `Clone::clone()` may be inefficient
      --> impl/src/ast.rs:85:21
       |
    85 |                     *display = attrs.display.clone();
       |                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use `clone_from()`: `display.clone_from(&attrs.display)`
       |
       = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#assigning_clones
       = note: `#[warn(clippy::assigning_clones)]` on by default

    warning: assigning the result of `Clone::clone()` may be inefficient
       --> impl/src/expand.rs:158:9
        |
    158 |         display_implied_bounds = display.implied_bounds.clone();
        |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use `clone_from()`: `display_implied_bounds.clone_from(&display.implied_bounds)`
        |
        = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#assigning_clones

    warning: assigning the result of `Clone::clone()` may be inefficient
       --> impl/src/expand.rs:402:21
        |
    402 |                     display_implied_bounds = display.implied_bounds.clone();
        |                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use `clone_from()`: `display_implied_bounds.clone_from(&display.implied_bounds)`
        |
        = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#assigning_clones

    warning: item has both inner and outer attributes
     --> tests/test_lints.rs:5:1
      |
    5 | / #[test]
    6 | | fn test_unused_qualifications() {
    7 | |     #![deny(unused_qualifications)]
      | |___________________________________^
      |
      = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#mixed_attributes_style
      = note: `#[warn(clippy::mixed_attributes_style)]` on by default

Make compatible with -Dwarnings