rust/tests/ui/suggestions/object-unsafe-trait-references-self.stderr

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error[E0038]: the trait `Trait` cannot be made into an object
--> $DIR/object-unsafe-trait-references-self.rs:9:12
|
LL | fn bar(x: &dyn Trait) {}
| ^^^^^^^^^ `Trait` 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/object-unsafe-trait-references-self.rs:2:22
|
LL | trait Trait {
| ----- this trait cannot be made into an object...
LL | fn baz(&self, _: Self) {}
| ^^^^ ...because method `baz` references the `Self` type in this parameter
LL |
LL | fn bat(&self) -> Self {}
| ^^^^ ...because method `bat` references the `Self` type in its return type
= help: consider moving `baz` to another trait
= help: consider moving `bat` to another trait
error[E0038]: the trait `Other` cannot be made into an object
--> $DIR/object-unsafe-trait-references-self.rs:13:12
|
LL | fn foo(x: &dyn Other) {}
| ^^^^^^^^^ `Other` 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/object-unsafe-trait-references-self.rs:11:14
|
LL | trait Other: Sized {}
| ----- ^^^^^ ...because it requires `Self: Sized`
| |
| this trait cannot be made into an object...
error[E0277]: the size for values of type `Self` cannot be known at compilation time
--> $DIR/object-unsafe-trait-references-self.rs:2:19
|
LL | fn baz(&self, _: Self) {}
| ^ doesn't have a size known at compile-time
|
= help: unsized fn params are gated as an unstable feature
help: consider further restricting `Self`
|
LL | fn baz(&self, _: Self) where Self: Sized {}
| +++++++++++++++++
help: function arguments must have a statically known size, borrowed types always have a known size
|
LL | fn baz(&self, _: &Self) {}
| +
error[E0308]: mismatched types
--> $DIR/object-unsafe-trait-references-self.rs:4:27
|
LL | trait Trait {
| ----------- expected this type parameter
...
LL | fn bat(&self) -> Self {}
| ^^ expected type parameter `Self`, found `()`
|
= note: expected type parameter `Self`
found unit type `()`
error[E0277]: the size for values of type `Self` cannot be known at compilation time
--> $DIR/object-unsafe-trait-references-self.rs:4:22
|
LL | fn bat(&self) -> Self {}
| ^^^^ doesn't have a size known at compile-time
|
= note: the return type of a function must have a statically known size
help: consider further restricting `Self`
|
LL | fn bat(&self) -> Self where Self: Sized {}
| +++++++++++++++++
error: aborting due to 5 previous errors
Some errors have detailed explanations: E0038, E0277, E0308.
For more information about an error, try `rustc --explain E0038`.