--- a/js/src/jsinterp.cpp
+++ b/js/src/jsinterp.cpp
@@ -1962,17 +1962,17 @@ BEGIN_CASE(JSOP_IN)
     regs.sp[-1].setBoolean(cond);
 }
 END_CASE(JSOP_IN)
 
 BEGIN_CASE(JSOP_ITER)
 {
     JS_ASSERT(regs.sp > regs.fp()->base());
     uint8_t flags = GET_UINT8(regs.pc);
-    if (!js_ValueToIterator(cx, flags, &regs.sp[-1]))
+    if (!ValueToIterator(cx, flags, &regs.sp[-1]))
         goto error;
     CHECK_INTERRUPT_HANDLER();
     JS_ASSERT(!regs.sp[-1].isPrimitive());
 }
 END_CASE(JSOP_ITER)
 
 BEGIN_CASE(JSOP_MOREITER)
 {
@@ -1996,17 +1996,17 @@ BEGIN_CASE(JSOP_ITERNEXT)
     if (!IteratorNext(cx, &itervp->toObject(), &regs.sp[-1]))
         goto error;
 }
 END_CASE(JSOP_ITERNEXT)
 
 BEGIN_CASE(JSOP_ENDITER)
 {
     JS_ASSERT(regs.sp - 1 >= regs.fp()->base());
-    bool ok = !!js_CloseIterator(cx, &regs.sp[-1].toObject());
+    bool ok = CloseIterator(cx, &regs.sp[-1].toObject());
     regs.sp--;
     if (!ok)
         goto error;
 }
 END_CASE(JSOP_ENDITER)
 
 BEGIN_CASE(JSOP_DUP)
 {
@@ -4325,23 +4325,20 @@ END_CASE(JSOP_ARRAYPUSH)
                 PUSH_COPY(cx->getPendingException());
                 cx->clearPendingException();
                 len = 0;
                 DO_NEXT_OP(len);
 
               case JSTRY_ITER: {
                 /* This is similar to JSOP_ENDITER in the interpreter loop. */
                 JS_ASSERT(JSOp(*regs.pc) == JSOP_ENDITER);
-                Value v = cx->getPendingException();
-                cx->clearPendingException();
-                bool ok = js_CloseIterator(cx, &regs.sp[-1].toObject());
+                bool ok = UnwindIteratorForException(cx, &regs.sp[-1].toObject());
                 regs.sp -= 1;
                 if (!ok)
                     goto error;
-                cx->setPendingException(v);
               }
            }
         } while (++tn != tnlimit);
 
       no_catch:
         /*
          * Propagate the exception or error to the caller unless the exception
          * is an asynchronous return from a generator.

--- a/js/src/jsiter.cpp
+++ b/js/src/jsiter.cpp
@@ -824,17 +824,17 @@ iterator_iterator(JSContext *cx, JSObjec
 
 static JSBool
 Iterator(JSContext *cx, uintN argc, Value *vp)
 {
     Value *argv = JS_ARGV(cx, vp);
     bool keyonly = argc >= 2 ? js_ValueToBoolean(argv[1]) : false;
     uintN flags = JSITER_OWNONLY | (keyonly ? 0 : (JSITER_FOREACH | JSITER_KEYVALUE));
     *vp = argc >= 1 ? argv[0] : UndefinedValue();
-    return js_ValueToIterator(cx, flags, vp);
+    return ValueToIterator(cx, flags, vp);
 }
 
 JSBool
 js_ThrowStopIteration(JSContext *cx)
 {
     Value v;
 
     JS_ASSERT(!JS_IsExceptionPending(cx));
@@ -866,22 +866,29 @@ iterator_next(JSContext *cx, uintN argc,
 
 #define JSPROP_ROPERM   (JSPROP_READONLY | JSPROP_PERMANENT)
 
 static JSFunctionSpec iterator_methods[] = {
     JS_FN(js_next_str,      iterator_next,  0,JSPROP_ROPERM),
     JS_FS_END
 };
 
+#if JS_HAS_GENERATORS
+static JSBool
+CloseGenerator(JSContext *cx, JSObject *genobj);
+#endif
+
+namespace js {
+
 /*
  * Call ToObject(v).__iterator__(keyonly) if ToObject(v).__iterator__ exists.
  * Otherwise construct the default iterator.
  */
-JS_FRIEND_API(JSBool)
-js_ValueToIterator(JSContext *cx, uintN flags, Value *vp)
+JSBool
+ValueToIterator(JSContext *cx, uintN flags, Value *vp)
 {
     /* JSITER_KEYVALUE must always come with JSITER_FOREACH */
     JS_ASSERT_IF(flags & JSITER_KEYVALUE, flags & JSITER_FOREACH);
 
     /*
      * Make sure the more/next state machine doesn't get stuck. A value might be
      * left in iterValue when a trace is left due to an operation time-out after
      * JSOP_MOREITER but before the value is picked up by FOR*.
@@ -909,23 +916,18 @@ js_ValueToIterator(JSContext *cx, uintN 
             if (!obj)
                 return false;
         }
     }
 
     return GetIterator(cx, obj, flags, vp);
 }
 
-#if JS_HAS_GENERATORS
-static JSBool
-CloseGenerator(JSContext *cx, JSObject *genobj);
-#endif
-
-JS_FRIEND_API(JSBool)
-js_CloseIterator(JSContext *cx, JSObject *obj)
+bool
+CloseIterator(JSContext *cx, JSObject *obj)
 {
     cx->iterValue.setMagic(JS_NO_ITER_VALUE);
 
     if (obj->isIterator()) {
         /* Remove enumerators from the active list, which is a stack. */
         NativeIterator *ni = obj->getNativeIterator();
 
         if (ni->flags & JSITER_ENUMERATE) {
@@ -945,16 +947,29 @@ js_CloseIterator(JSContext *cx, JSObject
 #if JS_HAS_GENERATORS
     else if (obj->isGenerator()) {
         return CloseGenerator(cx, obj);
     }
 #endif
     return JS_TRUE;
 }
 
+bool
+UnwindIteratorForException(JSContext *cx, JSObject *obj)
+{
+    Value v = cx->getPendingException();
+    cx->clearPendingException();
+    if (!CloseIterator(cx, obj))
+        return false;
+    cx->setPendingException(v);
+    return true;
+}
+
+} // namespace js
+
 /*
  * Suppress enumeration of deleted properties. This function must be called
  * when a property is deleted and there might be active enumerators.
  *
  * We maintain a list of active non-escaping for-in enumerators. To suppress
  * a property, we check whether each active enumerator contains the (obj, id)
  * pair and has not yet enumerated |id|. If so, and |id| is the next property,
  * we simply advance the cursor. Otherwise, we delete |id| from the list.

--- a/js/src/jsiter.h
+++ b/js/src/jsiter.h
@@ -176,29 +176,32 @@ VectorToValueIterator(JSContext *cx, JSO
 
 /*
  * Creates either a key or value iterator, depending on flags. For a value
  * iterator, performs value-lookup to convert the given list of jsids.
  */
 bool
 EnumeratedIdVectorToIterator(JSContext *cx, JSObject *obj, uintN flags, js::AutoIdVector &props, js::Value *vp);
 
-}
-
 /*
  * Convert the value stored in *vp to its iteration object. The flags should
  * contain JSITER_ENUMERATE if js_ValueToIterator is called when enumerating
  * for-in semantics are required, and when the caller can guarantee that the
  * iterator will never be exposed to scripts.
  */
-extern JS_FRIEND_API(JSBool)
-js_ValueToIterator(JSContext *cx, uintN flags, js::Value *vp);
+extern JSBool
+ValueToIterator(JSContext *cx, uintN flags, js::Value *vp);
 
-extern JS_FRIEND_API(JSBool)
-js_CloseIterator(JSContext *cx, JSObject *iterObj);
+extern bool
+CloseIterator(JSContext *cx, JSObject *iterObj);
+
+extern bool
+UnwindIteratorForException(JSContext *cx, JSObject *obj);
+
+}
 
 extern bool
 js_SuppressDeletedProperty(JSContext *cx, JSObject *obj, jsid id);
 
 extern bool
 js_SuppressDeletedElement(JSContext *cx, JSObject *obj, uint32_t index);
 
 extern bool

--- a/js/src/jswrapper.cpp
+++ b/js/src/jswrapper.cpp
@@ -651,17 +651,17 @@ CanReify(Value *vp)
            (obj = &vp->toObject())->getClass() == &IteratorClass &&
            (obj->getNativeIterator()->flags & JSITER_ENUMERATE);
 }
 
 struct AutoCloseIterator
 {
     AutoCloseIterator(JSContext *cx, JSObject *obj) : cx(cx), obj(obj) {}
 
-    ~AutoCloseIterator() { if (obj) js_CloseIterator(cx, obj); }
+    ~AutoCloseIterator() { if (obj) CloseIterator(cx, obj); }
 
     void clear() { obj = NULL; }
 
   private:
     JSContext *cx;
     JSObject *obj;
 };
 
@@ -696,17 +696,17 @@ Reify(JSContext *cx, JSCompartment *orig
             id = js_CheckForStringIndex(id);
             keys[i] = id;
             if (!origin->wrapId(cx, &keys[i]))
                 return false;
         }
     }
 
     close.clear();
-    if (!js_CloseIterator(cx, iterObj))
+    if (!CloseIterator(cx, iterObj))
         return false;
 
     if (isKeyIter)
         return VectorToKeyIterator(cx, obj, ni->flags, keys, vp);
     return VectorToValueIterator(cx, obj, ni->flags, keys, vp); 
 }
 
 bool

--- a/js/src/methodjit/InvokeHelpers.cpp
+++ b/js/src/methodjit/InvokeHelpers.cpp
@@ -146,24 +146,21 @@ top:
                 {
                   /*
                    * This is similar to JSOP_ENDITER in the interpreter loop,
                    * except the code now uses the stack slot normally used by
                    * JSOP_NEXTITER, namely regs.sp[-1] before the regs.sp -= 2
                    * adjustment and regs.sp[1] after, to save and restore the
                    * pending exception.
                    */
-                  Value v = cx->getPendingException();
                   JS_ASSERT(JSOp(*pc) == JSOP_ENDITER);
-                  cx->clearPendingException();
-                  bool ok = !!js_CloseIterator(cx, &cx->regs().sp[-1].toObject());
+                  bool ok = UnwindIteratorForException(cx, &cx->regs().sp[-1].toObject());
                   cx->regs().sp -= 1;
                   if (!ok)
                       goto top;
-                  cx->setPendingException(v);
                 }
             }
         }
     }
 
     return NULL;
 }
 

--- a/js/src/methodjit/StubCalls.cpp
+++ b/js/src/methodjit/StubCalls.cpp
@@ -1225,17 +1225,17 @@ stubs::GetPropNoCache(VMFrame &f, Proper
         THROW();
 
     regs.sp[-1] = rval;
 }
 
 void JS_FASTCALL
 stubs::Iter(VMFrame &f, uint32_t flags)
 {
-    if (!js_ValueToIterator(f.cx, flags, &f.regs.sp[-1]))
+    if (!ValueToIterator(f.cx, flags, &f.regs.sp[-1]))
         THROW();
     JS_ASSERT(!f.regs.sp[-1].isPrimitive());
 }
 
 static void
 InitPropOrMethod(VMFrame &f, PropertyName *name, JSOp op)
 {
     JSContext *cx = f.cx;
@@ -1300,17 +1300,17 @@ stubs::IterMore(VMFrame &f)
 
     return v.toBoolean();
 }
 
 void JS_FASTCALL
 stubs::EndIter(VMFrame &f)
 {
     JS_ASSERT(f.regs.sp - 1 >= f.fp()->base());
-    if (!js_CloseIterator(f.cx, &f.regs.sp[-1].toObject()))
+    if (!CloseIterator(f.cx, &f.regs.sp[-1].toObject()))
         THROW();
 }
 
 JSString * JS_FASTCALL
 stubs::TypeOf(VMFrame &f)
 {
     const Value &ref = f.regs.sp[-1];
     JSType type = JS_TypeOfValue(f.cx, ref);