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Commit | Line | Data |
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85aaf69f SL |
1 | // Reject mixing cyclic structure and Drop when using TypedArena. |
2 | // | |
5869c6ff | 3 | // (Compare against dropck-vec-cycle-checked.rs) |
85aaf69f | 4 | // |
5869c6ff | 5 | // (Also compare against ui-fulldeps/dropck-tarena-unsound-drop.rs, |
85aaf69f SL |
6 | // which is a reduction of this code to more directly show the reason |
7 | // for the error message we see here.) | |
8 | ||
ea8adc8c | 9 | #![feature(rustc_private)] |
85aaf69f | 10 | |
f035d41b | 11 | extern crate rustc_arena; |
85aaf69f | 12 | |
f035d41b | 13 | use rustc_arena::TypedArena; |
85aaf69f SL |
14 | use std::cell::Cell; |
15 | use id::Id; | |
16 | ||
17 | mod s { | |
62682a34 | 18 | use std::sync::atomic::{AtomicUsize, Ordering}; |
85aaf69f | 19 | |
62682a34 | 20 | static S_COUNT: AtomicUsize = AtomicUsize::new(0); |
85aaf69f SL |
21 | |
22 | pub fn next_count() -> usize { | |
23 | S_COUNT.fetch_add(1, Ordering::SeqCst) + 1 | |
24 | } | |
25 | } | |
26 | ||
27 | mod id { | |
28 | use s; | |
29 | #[derive(Debug)] | |
30 | pub struct Id { | |
31 | orig_count: usize, | |
32 | count: usize, | |
33 | } | |
34 | ||
35 | impl Id { | |
36 | pub fn new() -> Id { | |
37 | let c = s::next_count(); | |
38 | println!("building Id {}", c); | |
39 | Id { orig_count: c, count: c } | |
40 | } | |
41 | pub fn count(&self) -> usize { | |
42 | println!("Id::count on {} returns {}", self.orig_count, self.count); | |
43 | self.count | |
44 | } | |
45 | } | |
46 | ||
47 | impl Drop for Id { | |
48 | fn drop(&mut self) { | |
49 | println!("dropping Id {}", self.count); | |
50 | self.count = 0; | |
51 | } | |
52 | } | |
53 | } | |
54 | ||
55 | trait HasId { | |
56 | fn count(&self) -> usize; | |
57 | } | |
58 | ||
59 | #[derive(Debug)] | |
60 | struct CheckId<T:HasId> { | |
61 | v: T | |
62 | } | |
63 | ||
64 | #[allow(non_snake_case)] | |
65 | fn CheckId<T:HasId>(t: T) -> CheckId<T> { CheckId{ v: t } } | |
66 | ||
85aaf69f SL |
67 | impl<T:HasId> Drop for CheckId<T> { |
68 | fn drop(&mut self) { | |
69 | assert!(self.v.count() > 0); | |
70 | } | |
71 | } | |
72 | ||
73 | #[derive(Debug)] | |
74 | struct C<'a> { | |
75 | id: Id, | |
76 | v: Vec<CheckId<Cell<Option<&'a C<'a>>>>>, | |
77 | } | |
78 | ||
79 | impl<'a> HasId for Cell<Option<&'a C<'a>>> { | |
80 | fn count(&self) -> usize { | |
81 | match self.get() { | |
82 | None => 1, | |
83 | Some(c) => c.id.count(), | |
84 | } | |
85 | } | |
86 | } | |
87 | ||
88 | impl<'a> C<'a> { | |
89 | fn new() -> C<'a> { | |
90 | C { id: Id::new(), v: Vec::new() } | |
91 | } | |
92 | } | |
93 | ||
94 | fn f<'a>(arena: &'a TypedArena<C<'a>>) { | |
95 | let c1 = arena.alloc(C::new()); | |
96 | let c2 = arena.alloc(C::new()); | |
97 | let c3 = arena.alloc(C::new()); | |
98 | ||
99 | c1.v.push(CheckId(Cell::new(None))); | |
100 | c1.v.push(CheckId(Cell::new(None))); | |
101 | c2.v.push(CheckId(Cell::new(None))); | |
102 | c2.v.push(CheckId(Cell::new(None))); | |
103 | c3.v.push(CheckId(Cell::new(None))); | |
104 | c3.v.push(CheckId(Cell::new(None))); | |
105 | ||
106 | c1.v[0].v.set(Some(c2)); | |
107 | c1.v[1].v.set(Some(c3)); | |
108 | c2.v[0].v.set(Some(c2)); | |
109 | c2.v[1].v.set(Some(c3)); | |
110 | c3.v[0].v.set(Some(c1)); | |
111 | c3.v[1].v.set(Some(c2)); | |
112 | } | |
113 | ||
114 | fn main() { | |
0bf4aa26 | 115 | let arena = TypedArena::default(); |
c30ab7b3 | 116 | f(&arena); |
ff7c6d11 | 117 | } //~^ ERROR `arena` does not live long enough |