mirror of https://github.com/rust-lang/rust.git
27 lines
483 B
Rust
27 lines
483 B
Rust
//@ known-bug: rust-lang/rust#129219
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//@ compile-flags: -Zmir-opt-level=5 -Zvalidate-mir --edition=2018
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use core::marker::Unsize;
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pub trait CastTo<T: ?Sized>: Unsize<T> {}
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impl<T: ?Sized, U: ?Sized> CastTo<T> for U {}
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impl<T: ?Sized> Cast for T {}
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pub trait Cast {
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fn cast<T: ?Sized>(&self) -> &T
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where
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Self: CastTo<T>,
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{
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self
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}
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}
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pub trait Foo {}
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impl Foo for [i32; 0] {}
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fn main() {
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let x: &dyn Foo = &[];
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let x = x.cast::<[i32]>();
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}
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