rust/tests/ui/issues/issue-19380.stderr
Esteban Küber 8c04999226 On object safety error, mention new enum as alternative
When we encounter a `dyn Trait` that isn't object safe, look for its
implementors. If there's one, mention using it directly If there are
less than 9, mention the possibility of creating a new enum and using
that instead.

Account for object unsafe `impl Trait on dyn Trait {}`.  Make a
distinction between public and sealed traits.

Fix #80194.
2023-10-29 23:55:46 +00:00

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error[E0038]: the trait `Qiz` cannot be made into an object
--> $DIR/issue-19380.rs:11:29
|
LL | foos: &'static [&'static (dyn Qiz + 'static)]
| ^^^^^^^^^^^^^^^^^ `Qiz` 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/issue-19380.rs:2:6
|
LL | trait Qiz {
| --- this trait cannot be made into an object...
LL | fn qiz();
| ^^^ ...because associated function `qiz` has no `self` parameter
= help: only type `Foo` implements the trait, consider using it directly instead
help: consider turning `qiz` into a method by giving it a `&self` argument
|
LL | fn qiz(&self);
| +++++
help: alternatively, consider constraining `qiz` so it does not apply to trait objects
|
LL | fn qiz() where Self: Sized;
| +++++++++++++++++
error[E0038]: the trait `Qiz` cannot be made into an object
--> $DIR/issue-19380.rs:16:33
|
LL | const BAR : Bar = Bar { foos: &[&FOO]};
| ^^^^ `Qiz` 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/issue-19380.rs:2:6
|
LL | trait Qiz {
| --- this trait cannot be made into an object...
LL | fn qiz();
| ^^^ ...because associated function `qiz` has no `self` parameter
= help: only type `Foo` implements the trait, consider using it directly instead
= note: required for the cast from `&Foo` to `&'static (dyn Qiz + 'static)`
help: consider turning `qiz` into a method by giving it a `&self` argument
|
LL | fn qiz(&self);
| +++++
help: alternatively, consider constraining `qiz` so it does not apply to trait objects
|
LL | fn qiz() where Self: Sized;
| +++++++++++++++++
error: aborting due to 2 previous errors
For more information about this error, try `rustc --explain E0038`.