error: unrecognized repr on struct that implements RefCast
 --> tests/ui/unrecognized-repr.rs:4:19
  |
4 | #[repr(packed, C, usize, usize(0), usize = "0")]
  |                   ^^^^^

error: unrecognized repr on struct that implements RefCast
 --> tests/ui/unrecognized-repr.rs:4:26
  |
4 | #[repr(packed, C, usize, usize(0), usize = "0")]
  |                          ^^^^^^^^

error: unrecognized repr on struct that implements RefCast
 --> tests/ui/unrecognized-repr.rs:4:36
  |
4 | #[repr(packed, C, usize, usize(0), usize = "0")]
  |                                    ^^^^^^^^^^^

error: `#[repr(usize)]` attribute cannot be used on structs
 --> tests/ui/unrecognized-repr.rs:4:1
  |
4 | #[repr(packed, C, usize, usize(0), usize = "0")]
  | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  |
  = help: `#[repr(usize)]` can only be applied to enums

error[E0565]: malformed `repr` attribute input
 --> tests/ui/unrecognized-repr.rs:4:1
  |
4 | #[repr(packed, C, usize, usize(0), usize = "0")]
  | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^---^^^^^^^^^^^^^^^
  |                               |
  |                               didn't expect any arguments here
  |
  = note: for more information, visit <https://doc.rust-lang.org/reference/type-layout.html#representations>

error[E0565]: malformed `repr` attribute input
 --> tests/ui/unrecognized-repr.rs:4:1
  |
4 | #[repr(packed, C, usize, usize(0), usize = "0")]
  | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^-----^^
  |                                          |
  |                                          didn't expect any arguments here
  |
  = note: for more information, visit <https://doc.rust-lang.org/reference/type-layout.html#representations>