error: this argument is passed by value, but not consumed in the function body
 --> needless_pass_by_value.rs:9:23
  |
9 | fn foo<T: Default>(v: Vec<T>, w: Vec<T>, mut x: Vec<T>, y: Vec<T>) -> Vec<T> {
  |                       ^^^^^^ help: consider changing the type to: `&[T]`
  |
  = note: `-D needless-pass-by-value` implied by `-D warnings`

error: this argument is passed by value, but not consumed in the function body
  --> needless_pass_by_value.rs:23:11
   |
23 | fn bar(x: String, y: Wrapper) {
   |           ^^^^^^ help: consider changing the type to: `&str`

error: this argument is passed by value, but not consumed in the function body
  --> needless_pass_by_value.rs:23:22
   |
23 | fn bar(x: String, y: Wrapper) {
   |                      ^^^^^^^ help: consider taking a reference instead: `&Wrapper`

error: this argument is passed by value, but not consumed in the function body
  --> needless_pass_by_value.rs:29:63
   |
29 | fn test_borrow_trait<T: std::borrow::Borrow<str>, U>(t: T, u: U) {
   |                                                               ^ help: consider taking a reference instead: `&U`

error: this argument is passed by value, but not consumed in the function body
  --> needless_pass_by_value.rs:40:18
   |
40 | fn test_match(x: Option<Option<String>>, y: Option<Option<String>>) {
   |                  ^^^^^^^^^^^^^^^^^^^^^^
   |
help: consider taking a reference instead
   |
40 | fn test_match(x: &Option<Option<String>>, y: Option<Option<String>>) {
41 |     match *x {
   |

error: this argument is passed by value, but not consumed in the function body
  --> needless_pass_by_value.rs:53:24
   |
53 | fn test_destructure(x: Wrapper, y: Wrapper, z: Wrapper) {
   |                        ^^^^^^^ help: consider taking a reference instead: `&Wrapper`

error: this argument is passed by value, but not consumed in the function body
  --> needless_pass_by_value.rs:53:36
   |
53 | fn test_destructure(x: Wrapper, y: Wrapper, z: Wrapper) {
   |                                    ^^^^^^^
   |
help: consider taking a reference instead
   |
53 | fn test_destructure(x: Wrapper, y: &Wrapper, z: Wrapper) {
54 |     let Wrapper(s) = z; // moved
55 |     let Wrapper(ref t) = *y; // not moved
56 |     let Wrapper(_) = *y; // still not moved
   |

error: aborting due to 7 previous errors


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