55 lines
1.3 KiB
Rust
55 lines
1.3 KiB
Rust
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// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
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// file at the top-level directory of this distribution and at
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// http://rust-lang.org/COPYRIGHT.
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//
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// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
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// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
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// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
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// option. This file may not be copied, modified, or distributed
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// except according to those terms.
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#![feature(unsize, coerce_sized, coerce_unsized)]
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use std::{
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ops::{CoerceSized, CoerceUnsized},
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marker::{Unsize, PhantomData},
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};
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struct WrapperWithExtraField<T>(T, i32);
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impl<T, U> CoerceUnsized<WrapperWithExtraField<U>> for WrapperWithExtraField<T>
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where
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T: CoerceUnsized<U>,
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{}
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impl<T, U> CoerceSized<WrapperWithExtraField<T>> for WrapperWithExtraField<U>
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where
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T: CoerceUnsized<U>,
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U: CoerceSized<T>,
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{} //~^^^^ ERROR [E0378]
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struct MultiplePointers<T: ?Sized>{
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ptr1: *const T,
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ptr2: *const T,
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}
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// No CoerceUnsized impl
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impl<T: ?Sized, U: ?Sized> CoerceSized<MultiplePointers<T>> for MultiplePointers<U>
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where
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T: Unsize<U>,
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{} //~^^^ ERROR [E0378]
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struct NothingToCoerce<T: ?Sized> {
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data: PhantomData<T>,
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}
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// No CoerceUnsized impl
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impl<T: ?Sized, U: ?Sized> CoerceSized<NothingToCoerce<U>> for NothingToCoerce<T> {}
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//~^ ERROR [E0378]
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fn main() {}
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