mirror of https://github.com/rust-lang/rust
42 lines
576 B
Rust
42 lines
576 B
Rust
#![feature(type_alias_impl_trait)]
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#![allow(unused)]
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#![deny(improper_ctypes)]
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pub trait TraitA {
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type Assoc;
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}
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impl TraitA for u32 {
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type Assoc = u32;
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}
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pub trait TraitB {
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type Assoc;
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}
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impl<T> TraitB for T
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where
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T: TraitA,
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{
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type Assoc = <T as TraitA>::Assoc;
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}
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type AliasA = impl TraitA<Assoc = u32>;
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type AliasB = impl TraitB;
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fn use_of_a() -> AliasA {
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3
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}
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fn use_of_b() -> AliasB {
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3
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}
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extern "C" {
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fn lint_me() -> <AliasB as TraitB>::Assoc;
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//~^ ERROR `extern` block uses type `AliasB`, which is not FFI-safe
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}
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fn main() {}
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