1 // Copyright 2016 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
11 // compile-flags:-Zdump-mir=NEVER_MATCHED
13 // Regression test for #41697. Using dump-mir was triggering
14 // artificial cycles: during type-checking, we had to get the MIR for
15 // the constant expressions in `[u8; 2]`, which in turn would trigger
16 // an attempt to get the item-path, which in turn would request the
17 // types of the impl, which would trigger a cycle. We supressed this
18 // cycle now by forcing mir-dump to avoid asking for types of an impl.
20 #![feature(rustc_attrs)]
25 fn get(&self) -> [u8; 2];
28 impl Foo for [u8; 2] {
29 fn get(&self) -> [u8; 2] {
34 struct Bar<T: ?Sized>(T);
36 fn unsize_fat_ptr<'a>(x: &'a Bar<Foo + Send + 'a>) -> &'a Bar<Foo + 'a> {
40 fn unsize_nested_fat_ptr(x: Arc<Foo + Send>) -> Arc<Foo> {
45 let x: Box<Bar<Foo + Send>> = Box::new(Bar([1,2]));
46 assert_eq!(unsize_fat_ptr(&*x).0.get(), [1, 2]);
48 let x: Arc<Foo + Send> = Arc::new([3, 4]);
49 assert_eq!(unsize_nested_fat_ptr(x).get(), [3, 4]);