mirror of https://github.com/rust-lang/rust
39 lines
1.4 KiB
Plaintext
39 lines
1.4 KiB
Plaintext
error[E0277]: the size for values of type `T` cannot be known at compilation time
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--> $DIR/E0375.rs:6:8
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LL | struct Foo<T: ?Sized, U: ?Sized> {
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| - this type parameter needs to be `Sized`
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LL | a: i32,
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LL | b: T,
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| ^ doesn't have a size known at compile-time
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= note: only the last field of a struct may have a dynamically sized type
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= help: change the field's type to have a statically known size
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help: consider removing the `?Sized` bound to make the type parameter `Sized`
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LL - struct Foo<T: ?Sized, U: ?Sized> {
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LL + struct Foo<T, U: ?Sized> {
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help: borrowed types always have a statically known size
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LL | b: &T,
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| +
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help: the `Box` type always has a statically known size and allocates its contents in the heap
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LL | b: Box<T>,
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| ++++ +
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error[E0375]: implementing the trait `CoerceUnsized` requires multiple coercions
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--> $DIR/E0375.rs:10:12
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LL | impl<T, U> CoerceUnsized<Foo<U, T>> for Foo<T, U> {}
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| ^^^^^^^^^^^^^^^^^^^^^^^^ requires multiple coercions
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= note: `CoerceUnsized` may only be implemented for a coercion between structures with one field being coerced
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= note: currently, 2 fields need coercions: `b` (`T` to `U`), `c` (`U` to `T`)
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error: aborting due to 2 previous errors
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Some errors have detailed explanations: E0277, E0375.
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For more information about an error, try `rustc --explain E0277`.
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