---

yaml
---
r: 92779
b: refs/heads/auto
c: 1f76a9b
h: refs/heads/master
i:
  92777: 1901338
  92775: 24d1519
v: v3

Author: pcwalton

[refs]

@@ -13,7 +13,7 @@ refs/heads/try3: 9387340aab40a73e8424c48fd42f0c521a4875c0
 refs/tags/release-0.3.1: 495bae036dfe5ec6ceafd3312b4dca48741e845b
 refs/tags/release-0.4: e828ea2080499553b97dfe33b3f4d472b4562ad7
 refs/tags/release-0.5: 7e3bcfbf21278251ee936ad53e92e9b719702d73
-refs/heads/auto: f62faa89edb16a340a0be471037301ebf1457919
+refs/heads/auto: 1f76a9ba5ef3b9b1f903ef3fd0f932972566720c
 refs/heads/servo: af82457af293e2a842ba6b7759b70288da276167
 refs/tags/release-0.6: b4ebcfa1812664df5e142f0134a5faea3918544c
 refs/tags/0.1: b19db808c2793fe2976759b85a355c3ad8c8b336

branches/auto/src/librustc/middle/ty.rs

@@ -364,7 +364,7 @@ struct ctxt_ {
 
     // The set of external traits whose implementations have been read. This
     // is used for lazy resolution of traits.
-    populated_external_traits: @mut HashSet<ast::DefId>,
+    populated_external_traits: RefCell<HashSet<ast::DefId>>,
 
     // These two caches are used by const_eval when decoding external statics
     // and variants that are found.
@@ -1008,7 +1008,7 @@ pub fn mk_ctxt(s: session::Session,
         used_mut_nodes: RefCell::new(HashSet::new()),
         impl_vtables: RefCell::new(HashMap::new()),
         populated_external_types: RefCell::new(HashSet::new()),
-        populated_external_traits: @mut HashSet::new(),
+        populated_external_traits: RefCell::new(HashSet::new()),
 
         extern_const_statics: RefCell::new(HashMap::new()),
         extern_const_variants: RefCell::new(HashMap::new()),
@@ -4589,8 +4589,12 @@ pub fn populate_implementations_for_trait_if_necessary(
     if trait_id.crate == LOCAL_CRATE {
         return
     }
-    if tcx.populated_external_traits.contains(&trait_id) {
-        return
+    {
+        let populated_external_traits = tcx.populated_external_traits
+                                           .borrow();
+        if populated_external_traits.get().contains(&trait_id) {
+            return
+        }
     }
 
     csearch::each_implementation_for_trait(tcx.sess.cstore, trait_id,
@@ -4615,7 +4619,9 @@ pub fn populate_implementations_for_trait_if_necessary(
         impls.get().insert(implementation_def_id, implementation);
     });
 
-    tcx.populated_external_traits.insert(trait_id);
+    let mut populated_external_traits = tcx.populated_external_traits
+                                           .borrow_mut();
+    populated_external_traits.get().insert(trait_id);
 }
 
 /// Given the def_id of an impl, return the def_id of the trait it implements.