Deriving Clone and Copy twice generates bad diagnostics

[cyrgani]

Code

#[derive(Clone, Copy)]
#[derive(Clone, Copy)]
enum E {}

Current output

error[E0119]: conflicting implementations of trait `Clone` for type `E`
 --> src/lib.rs:2:10
  |
1 | #[derive(Clone, Copy)]
  |          ----- first implementation here
2 | #[derive(Clone, Copy)]
  |          ^^^^^ conflicting implementation for `E`
  |
  = note: this error originates in the derive macro `Clone` (in Nightly builds, run with -Z macro-backtrace for more info)

error[E0119]: conflicting implementations of trait `Copy` for type `E`
 --> src/lib.rs:2:17
  |
1 | #[derive(Clone, Copy)]
  |                 ---- first implementation here
2 | #[derive(Clone, Copy)]
  |                 ^^^^ conflicting implementation for `E`
  |
  = note: this error originates in the derive macro `Copy` (in Nightly builds, run with -Z macro-backtrace for more info)

error[E0507]: cannot move out of `*self` which is behind a shared reference
 --> src/lib.rs:2:10
  |
2 | #[derive(Clone, Copy)]
  |          ^^^^^ move occurs because `*self` has type `E`, which does not implement the `Copy` trait
  |
note: if `E` implemented `Clone`, you could clone the value
 --> src/lib.rs:3:1
  |
2 | #[derive(Clone, Copy)]
  |          ----- you could clone this value
3 | enum E {}
  | ^^^^^^ consider implementing `Clone` for this type
  = note: this error originates in the derive macro `Clone` (in Nightly builds, run with -Z macro-backtrace for more info)

error[E0507]: cannot move out of `*self` which is behind a shared reference
 --> src/lib.rs:1:10
  |
1 | #[derive(Clone, Copy)]
  |          ^^^^^ move occurs because `*self` has type `E`, which does not implement the `Copy` trait
  |
note: if `E` implemented `Clone`, you could clone the value
 --> src/lib.rs:3:1
  |
1 | #[derive(Clone, Copy)]
  |          ----- you could clone this value
2 | #[derive(Clone, Copy)]
3 | enum E {}
  | ^^^^^^ consider implementing `Clone` for this type
  = note: this error originates in the derive macro `Clone` (in Nightly builds, run with -Z macro-backtrace for more info)

Desired output

error[E0119]: conflicting implementations of trait `Clone` for type `E`
 --> src/lib.rs:2:10
  |
1 | #[derive(Clone, Copy)]
  |          ----- first implementation here
2 | #[derive(Clone, Copy)]
  |          ^^^^^ conflicting implementation for `E`
  |
  = note: this error originates in the derive macro `Clone` (in Nightly builds, run with -Z macro-backtrace for more info)

error[E0119]: conflicting implementations of trait `Copy` for type `E`
 --> src/lib.rs:2:17
  |
1 | #[derive(Clone, Copy)]
  |                 ---- first implementation here
2 | #[derive(Clone, Copy)]
  |                 ^^^^ conflicting implementation for `E`
  |
  = note: this error originates in the derive macro `Copy` (in Nightly builds, run with -Z macro-backtrace for more info)

Rationale and extra context

First encountered this with a macro that automatically derived Clone and Copy. The later two errors are pointing to internal implementation details and have wrong spans; they should be removed. They also suggest "consider implementing Clone for this type", which is nonsense.

Other cases

No response

Rust Version

1.83.0 nightly on playground

Anything else?

No response

[VulnBandit]

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