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8c04999226
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.
41 lines
2.1 KiB
Plaintext
41 lines
2.1 KiB
Plaintext
error[E0038]: the trait `Trait` cannot be made into an object
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--> $DIR/feature-gate-dispatch-from-dyn-missing-impl.rs:32:25
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LL | fn ptr(self: Ptr<Self>);
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| --------- help: consider changing method `ptr`'s `self` parameter to be `&self`: `&Self`
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...
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LL | Ptr(Box::new(4)) as Ptr<dyn Trait>;
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| ^^^^^^^^^^^^^^ `Trait` cannot be made into an object
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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>
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--> $DIR/feature-gate-dispatch-from-dyn-missing-impl.rs:25:18
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LL | trait Trait {
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| ----- this trait cannot be made into an object...
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LL | fn ptr(self: Ptr<Self>);
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| ^^^^^^^^^ ...because method `ptr`'s `self` parameter cannot be dispatched on
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= help: only type `i32` implements the trait, consider using it directly instead
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error[E0038]: the trait `Trait` cannot be made into an object
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--> $DIR/feature-gate-dispatch-from-dyn-missing-impl.rs:32:5
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LL | fn ptr(self: Ptr<Self>);
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| --------- help: consider changing method `ptr`'s `self` parameter to be `&self`: `&Self`
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...
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LL | Ptr(Box::new(4)) as Ptr<dyn Trait>;
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| ^^^^^^^^^^^^^^^^ `Trait` cannot be made into an object
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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>
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--> $DIR/feature-gate-dispatch-from-dyn-missing-impl.rs:25:18
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LL | trait Trait {
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| ----- this trait cannot be made into an object...
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LL | fn ptr(self: Ptr<Self>);
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| ^^^^^^^^^ ...because method `ptr`'s `self` parameter cannot be dispatched on
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= help: only type `i32` implements the trait, consider using it directly instead
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= note: required for the cast from `Ptr<{integer}>` to `Ptr<dyn Trait>`
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error: aborting due to 2 previous errors
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For more information about this error, try `rustc --explain E0038`.
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