1 files changed, 117 insertions, 0 deletions
diff --git a/tests/ui-fulldeps/dropck-tarena-cycle-checked.rs b/tests/ui-fulldeps/dropck-tarena-cycle-checked.rs
new file mode 100644
index 000000000..cc97971a0
--- /dev/null
+++ b/tests/ui-fulldeps/dropck-tarena-cycle-checked.rs
@@ -0,0 +1,117 @@
+// Reject mixing cyclic structure and Drop when using TypedArena.
+//
+// (Compare against dropck-vec-cycle-checked.rs)
+//
+// (Also compare against ui-fulldeps/dropck-tarena-unsound-drop.rs,
+//  which is a reduction of this code to more directly show the reason
+//  for the error message we see here.)
+
+#![feature(rustc_private)]
+
+extern crate rustc_arena;
+
+use rustc_arena::TypedArena;
+use std::cell::Cell;
+use id::Id;
+
+mod s {
+    use std::sync::atomic::{AtomicUsize, Ordering};
+
+    static S_COUNT: AtomicUsize = AtomicUsize::new(0);
+
+    pub fn next_count() -> usize {
+        S_COUNT.fetch_add(1, Ordering::SeqCst) + 1
+    }
+}
+
+mod id {
+    use s;
+    #[derive(Debug)]
+    pub struct Id {
+        orig_count: usize,
+        count: usize,
+    }
+
+    impl Id {
+        pub fn new() -> Id {
+            let c = s::next_count();
+            println!("building Id {}", c);
+            Id { orig_count: c, count: c }
+        }
+        pub fn count(&self) -> usize {
+            println!("Id::count on {} returns {}", self.orig_count, self.count);
+            self.count
+        }
+    }
+
+    impl Drop for Id {
+        fn drop(&mut self) {
+            println!("dropping Id {}", self.count);
+            self.count = 0;
+        }
+    }
+}
+
+trait HasId {
+    fn count(&self) -> usize;
+}
+
+#[derive(Debug)]
+struct CheckId<T:HasId> {
+    v: T
+}
+
+#[allow(non_snake_case)]
+fn CheckId<T:HasId>(t: T) -> CheckId<T> { CheckId{ v: t } }
+
+impl<T:HasId> Drop for CheckId<T> {
+    fn drop(&mut self) {
+        assert!(self.v.count() > 0);
+    }
+}
+
+#[derive(Debug)]
+struct C<'a> {
+    id: Id,
+    v: Vec<CheckId<Cell<Option<&'a C<'a>>>>>,
+}
+
+impl<'a> HasId for Cell<Option<&'a C<'a>>> {
+    fn count(&self) -> usize {
+        match self.get() {
+            None => 1,
+            Some(c) => c.id.count(),
+        }
+    }
+}
+
+impl<'a> C<'a> {
+    fn new() -> C<'a> {
+        C { id: Id::new(), v: Vec::new() }
+    }
+}
+
+fn f<'a>(arena: &'a TypedArena<C<'a>>) {
+    let c1 = arena.alloc(C::new());
+    let c2 = arena.alloc(C::new());
+    let c3 = arena.alloc(C::new());
+
+    c1.v.push(CheckId(Cell::new(None)));
+    c1.v.push(CheckId(Cell::new(None)));
+    c2.v.push(CheckId(Cell::new(None)));
+    c2.v.push(CheckId(Cell::new(None)));
+    c3.v.push(CheckId(Cell::new(None)));
+    c3.v.push(CheckId(Cell::new(None)));
+
+    c1.v[0].v.set(Some(c2));
+    c1.v[1].v.set(Some(c3));
+    c2.v[0].v.set(Some(c2));
+    c2.v[1].v.set(Some(c3));
+    c3.v[0].v.set(Some(c1));
+    c3.v[1].v.set(Some(c2));
+}
+
+fn main() {
+    let arena = TypedArena::default();
+    f(&arena);
+} //~^ ERROR `arena` does not live long enough