1 // Copyright 2015 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 // Test that we are imposing the requirement that every associated
12 // type of a bound that appears in the where clause on a struct must
13 // outlive the location in which the type appears. Issue #22246.
16 #![feature(rustc_attrs)]
18 ///////////////////////////////////////////////////////////////////////////
24 pub struct TheType<'b> {
28 impl<'b> TheTrait for TheType<'b> {
29 type TheAssocType = &'b ();
32 ///////////////////////////////////////////////////////////////////////////
34 pub struct WithAssoc<T:TheTrait> {
38 pub struct WithoutAssoc<T> {
42 fn with_assoc<'a,'b>() {
43 // For this type to be valid, the rules require that all
44 // associated types of traits that appear in `WithAssoc` must
45 // outlive 'a. In this case, that means TheType<'b>::TheAssocType,
46 // which is &'b (), must outlive 'a.
48 // FIXME (#54943) NLL doesn't enforce WF condition in unreachable code if
49 // `_x` is changed to `_`
50 let _x: &'a WithAssoc<TheType<'b>> = loop { };
51 //~^ ERROR reference has a longer lifetime
54 fn with_assoc1<'a,'b>() where 'b : 'a {
55 // For this type to be valid, the rules require that all
56 // associated types of traits that appear in `WithAssoc` must
57 // outlive 'a. In this case, that means TheType<'b>::TheAssocType,
58 // which is &'b (), must outlive 'a, so 'b : 'a must hold, and
59 // that is in the where clauses, so we're fine.
61 let _x: &'a WithAssoc<TheType<'b>> = loop { };
64 fn without_assoc<'a,'b>() {
65 // Here there are no associated types but there is a requirement
66 // that `'b:'a` holds because the `'b` appears in `TheType<'b>`.
68 let _x: &'a WithoutAssoc<TheType<'b>> = loop { };
69 //~^ ERROR reference has a longer lifetime
72 fn call_with_assoc<'a,'b>() {
73 // As `with_assoc`, but just checking that we impose the same rule
74 // on the value supplied for the type argument, even when there is
77 call::<&'a WithAssoc<TheType<'b>>>();
78 //~^ ERROR reference has a longer lifetime
81 fn call_without_assoc<'a,'b>() {
82 // As `without_assoc`, but in a distinct scenario.
84 call::<&'a WithoutAssoc<TheType<'b>>>(); //~ ERROR reference has a longer lifetime