error[E0517]: attribute should be applied to struct, enum or union
  --> $DIR/E0517.rs:11:8
   |
LL | #[repr(C)] //~ ERROR: E0517
   |        ^
LL | type Foo = u8;
   | -------------- not a struct, enum or union

error[E0517]: attribute should be applied to struct or union
  --> $DIR/E0517.rs:14:8
   |
LL | #[repr(packed)] //~ ERROR: E0517
   |        ^^^^^^
LL | enum Foo2 {Bar, Baz}
   | -------------------- not a struct or union

error[E0517]: attribute should be applied to enum
  --> $DIR/E0517.rs:17:8
   |
LL | #[repr(u8)] //~ ERROR: E0517
   |        ^^
LL | struct Foo3 {bar: bool, baz: bool}
   | ---------------------------------- not an enum

error[E0517]: attribute should be applied to struct, enum or union
  --> $DIR/E0517.rs:20:8
   |
LL |   #[repr(C)] //~ ERROR: E0517
   |          ^
LL | / impl Foo3 {
LL | | }
   | |_- not a struct, enum or union

error: aborting due to 4 previous errors

For more information about this error, try `rustc --explain E0517`.