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// This is a regression test for issues that came up during review of the (closed)
// PR #132289; this 3-ish-crate (including std) test case is adapted from
// the third example from @steffahn during review.
// https://github.com/rust-lang/rust/pull/132289#issuecomment-2564599221
//@ run-pass
//@ check-run-results
//@ aux-build: pr_review_132289_3_lib.rs
extern crate pr_review_132289_3_lib;
use std::ops::Index;
use pr_review_132289_3_lib::{call, Trait};
trait SubIndex<I>: Index<I> {}
struct Param;
trait Project {
type Ty: ?Sized;
}
impl Project for () {
type Ty = dyn SubIndex<Param, Output = ()>;
}
impl Index<Param> for <() as Project>::Ty {
type Output = ();
fn index(&self, _: Param) -> &() {
&()
}
}
struct Struct;
impl Trait for Struct {
fn f(&self)
where
// higher-ranked to allow potentially-false bounds
for<'a> dyn Index<(), Output = ()>: Index<()>,
// after #132289 rustc used to believe this bound false
{
println!("hello!");
}
}
fn main() {
call(&Struct); // <- would segfault if the method `f` wasn't part of the vtable
}
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