rust/tests/ui/traits/object/safety.stderr

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error[E0038]: the trait `Tr` cannot be made into an object
--> $DIR/safety.rs:15:22
|
LL | let _: &dyn Tr = &St;
| ^^^ `Tr` cannot be made into an object
|
note: for a trait to be "object safe" it needs to allow building a vtable to allow the call to be resolvable dynamically; for more information visit <https://doc.rust-lang.org/reference/items/traits.html#object-safety>
--> $DIR/safety.rs:4:8
|
LL | trait Tr {
| -- this trait cannot be made into an object...
LL | fn foo();
| ^^^ ...because associated function `foo` has no `self` parameter
= help: only type `St` implements the trait, consider using it directly instead
= note: required for the cast from `&St` to `&dyn Tr`
help: consider turning `foo` into a method by giving it a `&self` argument
|
LL | fn foo(&self);
| +++++
help: alternatively, consider constraining `foo` so it does not apply to trait objects
|
LL | fn foo() where Self: Sized;
| +++++++++++++++++
error[E0038]: the trait `Tr` cannot be made into an object
--> $DIR/safety.rs:15:12
|
LL | let _: &dyn Tr = &St;
| ^^^^^^^ `Tr` cannot be made into an object
|
note: for a trait to be "object safe" it needs to allow building a vtable to allow the call to be resolvable dynamically; for more information visit <https://doc.rust-lang.org/reference/items/traits.html#object-safety>
--> $DIR/safety.rs:4:8
|
LL | trait Tr {
| -- this trait cannot be made into an object...
LL | fn foo();
| ^^^ ...because associated function `foo` has no `self` parameter
= help: only type `St` implements the trait, consider using it directly instead
help: consider turning `foo` into a method by giving it a `&self` argument
|
LL | fn foo(&self);
| +++++
help: alternatively, consider constraining `foo` so it does not apply to trait objects
|
LL | fn foo() where Self: Sized;
| +++++++++++++++++
error: aborting due to 2 previous errors
For more information about this error, try `rustc --explain E0038`.