diff --git a/js/src/jsgc.cpp b/js/src/jsgc.cpp
index aa05542133..7834d9b434 100644
--- a/js/src/jsgc.cpp
+++ b/js/src/jsgc.cpp
@@ -3647,7 +3647,7 @@ class MOZ_RAII js::gc::AutoRunParallelTask : public GCParallelTask
 };
 
 void
-GCRuntime::purgeRuntimeForMinorGC(AutoLockForExclusiveAccess& lock)
+GCRuntime::purgeRuntimeForMinorGC()
 { 
     // If external strings become nursery allocable, remember to call
     // zone->externalStringCache().purge() (and delete this assert.)
diff --git a/js/src/vm/Caches.h b/js/src/vm/Caches.h
index dd5e3666d2..c00e86a561 100644
--- a/js/src/vm/Caches.h
+++ b/js/src/vm/Caches.h
@@ -93,7 +93,7 @@ struct EvalCacheHashPolicy
     static bool match(const EvalCacheEntry& entry, const EvalCacheLookup& l);
 };
 
-typedef HashSet<EvalCacheEntry, EvalCacheHashPolicy, SystemAllocPolicy> EvalCache;
+typedef GCHashSet<EvalCacheEntry, EvalCacheHashPolicy, SystemAllocPolicy> EvalCache;
 
 struct LazyScriptHashPolicy
 {
@@ -315,6 +315,25 @@ class ContextCaches
     js::MathCache* maybeGetMathCache() {
         return mathCache_.get();
     }
+    
+    void purgeForMinorGC(JSRuntime* rt) {
+        newObjectCache.clearNurseryObjects(rt);
+        evalCache.sweep();
+    }
+
+    void purgeForCompaction() {
+        newObjectCache.purge();
+        if (evalCache.initialized())
+            evalCache.clear();
+    }
+
+    void purge() {
+        purgeForCompaction();
+        gsnCache.purge();
+        envCoordinateNameCache.purge();
+        nativeIterCache.purge();
+        uncompressedSourceCache.purge();
+    }
 };
 
 } // namespace js