---

yaml
---
r: 20796
b: refs/heads/snap-stage3
c: 0c3158b
h: refs/heads/master
v: v3

Author: bblum

[refs]

@@ -1,7 +1,7 @@
 ---
 refs/heads/master: e430a699f2c60890d9b86069fd0c68a70ece7120
 refs/heads/snap-stage1: e33de59e47c5076a89eadeb38f4934f58a3618a6
-refs/heads/snap-stage3: fd536d9d3e5a54b0a7b551a795198210fc229da3
+refs/heads/snap-stage3: 0c3158b3a57129e8fb2a71ae0d0fceb985fc2098
 refs/heads/try: ffbe0e0e00374358b789b0037bcb3a577cd218be
 refs/tags/release-0.1: 1f5c5126e96c79d22cb7862f75304136e204f105
 refs/heads/ndm: f3868061cd7988080c30d6d5bf352a5a5fe2460b

branches/snap-stage3/src/libcore/arc.rs

@@ -112,6 +112,7 @@ impl methods<T: send> for exclusive<T> {
     unsafe fn with<U>(f: fn(sys::condition, x: &mut T) -> U) -> U {
         let ptr: ~arc_data<ex_data<T>> =
             unsafe::reinterpret_cast(self.data);
+        assert ptr.count > 0;
         let r = {
             let rec: &ex_data<T> = &(*ptr).data;
             rec.lock.lock_cond(|c| f(c, &mut rec.data))