rust/src/test/ui/traits/trait-object-safety.stderr

50 lines
2.1 KiB
Plaintext
Raw Normal View History

2018-08-08 07:28:26 -05:00
error[E0038]: the trait `Tr` cannot be made into an object
2019-05-28 13:46:13 -05:00
--> $DIR/trait-object-safety.rs:15:22
2018-08-08 07:28:26 -05:00
|
2019-05-28 13:46:13 -05:00
LL | let _: &dyn Tr = &St;
| ^^^ the trait `Tr` cannot be made into an object
2018-08-08 07:28:26 -05:00
|
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/trait-object-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
= note: required because of the requirements on the impl of `CoerceUnsized<&dyn Tr>` for `&St`
= note: required by cast to type `&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;
| ^^^^^^^^^^^^^^^^^
2018-08-08 07:28:26 -05:00
error[E0038]: the trait `Tr` cannot be made into an object
2018-12-25 09:56:47 -06:00
--> $DIR/trait-object-safety.rs:15:12
2018-08-08 07:28:26 -05:00
|
LL | let _: &dyn Tr = &St;
| ^^^^^^^ the trait `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/trait-object-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: 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;
| ^^^^^^^^^^^^^^^^^
2018-08-08 07:28:26 -05:00
error: aborting due to 2 previous errors
For more information about this error, try `rustc --explain E0038`.