3 files changed, 15 insertions, 9 deletions
diff --git a/src/qml/jsruntime/qv4runtime.cpp b/src/qml/jsruntime/qv4runtime.cpp
index 2c00826b46..650f5c6735 100644
--- a/src/qml/jsruntime/qv4runtime.cpp
+++ b/src/qml/jsruntime/qv4runtime.cpp
@@ -715,7 +715,7 @@ ReturnedValue Runtime::method_getIterator(ExecutionEngine *engine, const Value &
     return engine->newForInIteratorObject(o)->asReturnedValue();
 }
 
-ReturnedValue Runtime::method_iteratorNext(ExecutionEngine *engine, const Value &iterator, int returnUndefinedWhenDone)
+ReturnedValue Runtime::method_iteratorNext(ExecutionEngine *engine, const Value &iterator, Value *value)
 {
     Q_ASSERT(iterator.isObject());
 
@@ -727,10 +727,14 @@ ReturnedValue Runtime::method_iteratorNext(ExecutionEngine *engine, const Value
     ScopedObject o(scope, f->call(cData));
     if (!o)
         return engine->throwTypeError();
-    ScopedValue v(scope, o->get(engine->id_done()));
-    if (v->toBoolean() == true)
-        return returnUndefinedWhenDone ? Encode::undefined() : Primitive::emptyValue().asReturnedValue();
-    return o->get(engine->id_value());
+    ScopedValue d(scope, o->get(engine->id_done()));
+    bool done = d->toBoolean();
+    if (done) {
+        *value = Encode::undefined();
+    } else {
+        *value = o->get(engine->id_value());
+    }
+    return Encode(done);
 }
 
 ReturnedValue Runtime::method_destructureRestElement(ExecutionEngine *engine, const Value &iterator)
@@ -742,10 +746,12 @@ ReturnedValue Runtime::method_destructureRestElement(ExecutionEngine *engine, co
     array->arrayCreate();
     uint index = 0;
     while (1) {
-        ScopedValue n(scope, method_iteratorNext(engine, iterator, false));
+        ScopedValue n(scope);
+        ScopedValue done(scope, method_iteratorNext(engine, iterator, n));
         if (engine->hasException)
             return Encode::undefined();
-        if (n->isEmpty())
+        Q_ASSERT(done->isBoolean());
+        if (done->booleanValue())
             break;
         array->arraySet(index, n);
         ++index;
diff --git a/src/qml/jsruntime/qv4runtimeapi_p.h b/src/qml/jsruntime/qv4runtimeapi_p.h
index 0d27fbfe7b..a22a053cd1 100644
--- a/src/qml/jsruntime/qv4runtimeapi_p.h
+++ b/src/qml/jsruntime/qv4runtimeapi_p.h
@@ -146,7 +146,7 @@ struct ExceptionCheck<void (*)(QV4::NoThrowEngine *, A, B, C)> {
     \
     /* for-in, for-of and array destructuring */ \
     F(ReturnedValue, getIterator, (ExecutionEngine *engine, const Value &in, int iterator)) \
-    F(ReturnedValue, iteratorNext, (ExecutionEngine *engine, const Value &iterator, int returnUndefinedWhenDone)) \
+    F(ReturnedValue, iteratorNext, (ExecutionEngine *engine, const Value &iterator, Value *value)) \
     F(ReturnedValue, destructureRestElement, (ExecutionEngine *engine, const Value &iterator)) \
     \
     /* unary operators */ \
diff --git a/src/qml/jsruntime/qv4vme_moth.cpp b/src/qml/jsruntime/qv4vme_moth.cpp
index 8b45226fcd..17ed1ae044 100644
--- a/src/qml/jsruntime/qv4vme_moth.cpp
+++ b/src/qml/jsruntime/qv4vme_moth.cpp
@@ -961,7 +961,7 @@ QV4::ReturnedValue VME::interpret(CppStackFrame &frame, const uchar *code)
 
     MOTH_BEGIN_INSTR(IteratorNext)
         STORE_ACC();
-        acc = Runtime::method_iteratorNext(engine, accumulator, returnUndefinedWhenDone);
+        acc = Runtime::method_iteratorNext(engine, accumulator, &STACK_VALUE(value));
         CHECK_EXCEPTION;
     MOTH_END_INSTR(IteratorNext)