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			41 lines
		
	
	
		
			2.3 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
			
		
		
	
	
			41 lines
		
	
	
		
			2.3 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
error[E0378]: the trait `DispatchFromDyn` may only be implemented for structs containing the field being coerced, ZST fields with 1 byte alignment, and nothing else
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  --> $DIR/invalid_dispatch_from_dyn_impls.rs:10:1
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LL | impl<T, U> DispatchFromDyn<WrapperWithExtraField<U>> for WrapperWithExtraField<T>
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   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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   = note: extra field `1` of type `i32` is not allowed
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error[E0378]: implementing the `DispatchFromDyn` trait requires multiple coercions
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  --> $DIR/invalid_dispatch_from_dyn_impls.rs:21:1
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LL | impl<T: ?Sized, U: ?Sized> DispatchFromDyn<MultiplePointers<U>> for MultiplePointers<T>
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   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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   = note: the trait `DispatchFromDyn` may only be implemented for a coercion between structures with a single field being coerced
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   = note: currently, 2 fields need coercions: `ptr1` (`*const T` to `*const U`), `ptr2` (`*const T` to `*const U`)
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error[E0378]: the trait `DispatchFromDyn` may only be implemented for a coercion between structures with a single field being coerced, none found
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  --> $DIR/invalid_dispatch_from_dyn_impls.rs:31:1
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LL | impl<T: ?Sized, U: ?Sized> DispatchFromDyn<NothingToCoerce<T>> for NothingToCoerce<U> {}
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   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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error[E0378]: structs implementing `DispatchFromDyn` may not have `#[repr(packed)]` or `#[repr(C)]`
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  --> $DIR/invalid_dispatch_from_dyn_impls.rs:37:1
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LL | impl<T: ?Sized, U: ?Sized> DispatchFromDyn<HasReprC<U>> for HasReprC<T>
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   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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error[E0378]: the trait `DispatchFromDyn` may only be implemented for structs containing the field being coerced, ZST fields with 1 byte alignment, and nothing else
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  --> $DIR/invalid_dispatch_from_dyn_impls.rs:46:1
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LL | impl<T: ?Sized, U: ?Sized> DispatchFromDyn<OverAligned<U>> for OverAligned<T>
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   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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   = note: extra field `1` of type `OverAlignedZst` is not allowed
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error: aborting due to 5 previous errors
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For more information about this error, try `rustc --explain E0378`.
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