mirror of https://github.com/rust-lang/rust
30 lines
952 B
Rust
30 lines
952 B
Rust
// This test demonstrates a limitation of the trait solver.
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// Basically, one might think that `T` was covered by the projection since the
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// latter appears to normalize to a local type. However, since we instantiate the
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// constituent types of the self type of impls with fresh infer vars and try to
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// normalize them during orphan checking, we wind up trying to normalize a
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// projection whose self type is an infer var which unconditionally fails due to
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// ambiguity.
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//@ revisions: classic next
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//@[next] compile-flags: -Znext-solver
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//@ check-pass
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//@ compile-flags: --crate-type=lib
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//@ aux-crate:foreign=parametrized-trait.rs
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//@ edition:2021
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trait Project { type Output; }
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impl<T> Project for T {
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type Output = Local;
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}
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struct Local;
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impl<T> foreign::Trait1<Local, T> for <T as Project>::Output {}
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//~^ WARNING type parameter `T` must be covered by another type
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//~| WARNING this was previously accepted by the compiler
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fn main() {}
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