mirror of https://github.com/rust-lang/rust
45 lines
1.0 KiB
Rust
45 lines
1.0 KiB
Rust
//@ compile-flags: -Znext-solver
|
|
//@ check-pass
|
|
#![feature(trivial_bounds, marker_trait_attr)]
|
|
#![allow(trivial_bounds)]
|
|
|
|
// This previously triggered a bug in the provisional cache.
|
|
//
|
|
// This has the proof tree
|
|
// - `Root: Trait` proven via impl
|
|
// - `MultipleCandidates: Trait`
|
|
// - candidate: overflow-impl
|
|
// - `Root: Trait` (inductive cycle ~> OVERFLOW)
|
|
// - candidate: trivial-impl ~> YES
|
|
// - merge respones ~> YES
|
|
// - `MultipleCandidates: Trait` (in provisional cache ~> OVERFLOW)
|
|
//
|
|
// We previously incorrectly treated the `MultipleCandidates: Trait` as
|
|
// overflow because it was in the cache and reached via an inductive cycle.
|
|
// It should be `YES`.
|
|
|
|
struct Root;
|
|
struct MultipleCandidates;
|
|
|
|
#[marker]
|
|
trait Trait {}
|
|
impl Trait for Root
|
|
where
|
|
MultipleCandidates: Trait,
|
|
MultipleCandidates: Trait,
|
|
{}
|
|
|
|
// overflow-impl
|
|
impl Trait for MultipleCandidates
|
|
where
|
|
Root: Trait,
|
|
{}
|
|
// trivial-impl
|
|
impl Trait for MultipleCandidates {}
|
|
|
|
fn impls_trait<T: Trait>() {}
|
|
|
|
fn main() {
|
|
impls_trait::<Root>();
|
|
}
|