error: malformed `derive` attribute input
 --> $DIR/malformed_derive_handled_by_rustc.rs:7:5
  |
7 |     #[derive]
  |     ^^^^^^^^^ help: must be of the form: `#[derive(Trait1, Trait2, ...)]`

error: malformed `derive` attribute input
 --> $DIR/malformed_derive_handled_by_rustc.rs:8:5
  |
8 |     #[derive = ""]
  |     ^^^^^^^^^^^^^^ help: must be of the form: `#[derive(Trait1, Trait2, ...)]`

error: wrong meta list delimiters
 --> $DIR/malformed_derive_handled_by_rustc.rs:9:13
  |
9 |     #[derive[Debug]]
  |             ^^^^^^^
  |
help: the delimiters should be `(` and `)`
  |
9 |     #[derive(Debug)]
  |             ~     ~

error[E0277]: `Raw<u8>` doesn't implement `Debug`
  --> $DIR/malformed_derive_handled_by_rustc.rs:6:1
   |
6  | / bitfields! {
7  | |     #[derive]
8  | |     #[derive = ""]
9  | |     #[derive[Debug]]
   | |              ----- in this derive macro expansion
10 | |     struct WithMalformedDerive : u8 {}
11 | | }
   | |_^ `Raw<u8>` cannot be formatted using `{:?}` because it doesn't implement `Debug`
   |
   = help: the trait `Debug` is not implemented for `Raw<u8>`
   = note: this error originates in the derive macro `Debug` (in Nightly builds, run with -Z macro-backtrace for more info)