24 lines
512 B
Rust
24 lines
512 B
Rust
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// revisions: current next
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//[next] compile-flags: -Ztrait-solver=next
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#![feature(trait_upcasting)]
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trait Super {
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type Assoc;
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}
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trait Sub: Super {}
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impl<T: ?Sized> Super for T {
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type Assoc = i32;
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}
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fn illegal(x: &dyn Sub<Assoc = ()>) -> &dyn Super<Assoc = i32> { x }
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//~^ ERROR mismatched types
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// Want to make sure that we can't "upcast" to a supertrait that has a different
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// associated type that is instead provided by a blanket impl (and doesn't come
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// from the object bounds).
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fn main() {}
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