24 lines
647 B
Rust
24 lines
647 B
Rust
#![feature(unsize, coerce_unsized)]
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// Verfies that non-PhantomData ZSTs still cause coercions to fail.
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// They might have additional semantics that we don't want to bulldoze.
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use std::marker::{Unsize, PhantomData};
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use std::ops::CoerceUnsized;
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struct NotPhantomData<T: ?Sized>(PhantomData<T>);
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struct MyRc<T: ?Sized> {
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_ptr: *const T,
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_boo: NotPhantomData<T>,
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}
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impl<T: ?Sized + Unsize<U>, U: ?Sized> CoerceUnsized<MyRc<U>> for MyRc<T>{ } //~ERROR
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fn main() {
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let data = [1, 2, 3];
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let iter = data.iter();
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let x = MyRc { _ptr: &iter, _boo: NotPhantomData(PhantomData) };
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let _y: MyRc<dyn Iterator<Item=&u32>> = x;
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}
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