error[E0599]: the method `as_dyn_error` exists for reference `&NotError`, but its trait bounds were not satisfied --> tests/ui/source-enum-not-error.rs:9:14 | 4 | pub struct NotError; | -------------------- | | | doesn't satisfy `NotError: AsDynError` | doesn't satisfy `NotError: std::error::Error` ... 9 | Broken { source: NotError }, | ^^^^^^ method cannot be called on `&NotError` due to unsatisfied trait bounds | = note: the following trait bounds were not satisfied: `NotError: std::error::Error` which is required by `NotError: AsDynError` `&NotError: std::error::Error` which is required by `&NotError: AsDynError` note: the following trait must be implemented --> $RUST/std/src/error.rs | | / pub trait Error: Debug + Display { | | /// The lower-level source of this error, if any. | | /// | | /// # Examples ... | | | } | | } | |_^