| error[E0277]: the trait bound `A: Copy` is not satisfied | 
 |   --> $DIR/wf-enum-fields-struct-variant.rs:13:12 | 
 |    | | 
 | LL |         f: IsCopy<A> | 
 |    |            ^^^^^^^^^ the trait `Copy` is not implemented for `A` | 
 |    | | 
 | note: required by a bound in `IsCopy` | 
 |   --> $DIR/wf-enum-fields-struct-variant.rs:7:17 | 
 |    | | 
 | LL | struct IsCopy<T:Copy> { | 
 |    |                 ^^^^ required by this bound in `IsCopy` | 
 | help: consider restricting type parameter `A` with trait `Copy` | 
 |    | | 
 | LL | enum AnotherEnum<A: std::marker::Copy> { | 
 |    |                   +++++++++++++++++++ | 
 |  | 
 | error: aborting due to 1 previous error | 
 |  | 
 | For more information about this error, try `rustc --explain E0277`. |