rust/tests/ui/traits/non_lifetime_binders/supertrait-object-safety.st...

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warning: the feature `non_lifetime_binders` is incomplete and may not be safe to use and/or cause compiler crashes
--> $DIR/supertrait-object-safety.rs:1:12
|
LL | #![feature(non_lifetime_binders)]
| ^^^^^^^^^^^^^^^^^^^^
|
= note: see issue #108185 <https://github.com/rust-lang/rust/issues/108185> for more information
= note: `#[warn(incomplete_features)]` on by default
error[E0038]: the trait `Foo` cannot be made into an object
--> $DIR/supertrait-object-safety.rs:19:23
|
LL | let x: &dyn Foo = &();
| ^^^ `Foo` 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/supertrait-object-safety.rs:4:12
|
LL | trait Foo: for<T> Bar<T> {}
| --- ^^^^^^^^^^^^^ ...because where clause cannot reference non-lifetime `for<...>` variables
| |
| this trait cannot be made into an object...
= help: only type `()` implements the trait, consider using it directly instead
= note: required for the cast from `&()` to `&dyn Foo`
error[E0038]: the trait `Foo` cannot be made into an object
--> $DIR/supertrait-object-safety.rs:19:12
|
LL | let x: &dyn Foo = &();
| ^^^^^^^^ `Foo` 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/supertrait-object-safety.rs:4:12
|
LL | trait Foo: for<T> Bar<T> {}
| --- ^^^^^^^^^^^^^ ...because where clause cannot reference non-lifetime `for<...>` variables
| |
| this trait cannot be made into an object...
= help: only type `()` implements the trait, consider using it directly instead
error[E0038]: the trait `Foo` cannot be made into an object
--> $DIR/supertrait-object-safety.rs:22:5
|
LL | needs_bar(x);
| ^^^^^^^^^ `Foo` 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/supertrait-object-safety.rs:4:12
|
LL | trait Foo: for<T> Bar<T> {}
| --- ^^^^^^^^^^^^^ ...because where clause cannot reference non-lifetime `for<...>` variables
| |
| this trait cannot be made into an object...
= help: only type `()` implements the trait, consider using it directly instead
error: aborting due to 3 previous errors; 1 warning emitted
For more information about this error, try `rustc --explain E0038`.