rust: sync: allow coercion from `Arc<T>` to `Arc<U>`

The coercion is only allowed if `U` is a compatible dynamically-sized
type (DST). For example, if we have some type `X` that implements trait
`Y`, then this allows `Arc<X>` to be coerced into `Arc<dyn Y>`.

Suggested-by: Gary Guo <[email protected]>
Signed-off-by: Wedson Almeida Filho <[email protected]>
Reviewed-by: Alice Ryhl <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Reviewed-by: Vincenzo Palazzo <[email protected]>
Acked-by: Boqun Feng <[email protected]>
Signed-off-by: Miguel Ojeda <[email protected]>

0 files changed, 0 insertions, 0 deletions