QML: Replace QPointer with a QQmlQPointer (which is trivial)

One of the steps needed to make QV4::Heap::structs trivial.

Change-Id: Ic4d73f15035af21c8a682aaad1ee68cdd91f8e7d
Reviewed-by: Lars Knoll <lars.knoll@qt.io>

12 files changed, 135 insertions, 52 deletions

diff --git a/src/qml/jsruntime/qv4qobjectwrapper.cpp b/src/qml/jsruntime/qv4qobjectwrapper.cpp
index 56d7ea0a59..202b7d3525 100644
--- a/src/qml/jsruntime/qv4qobjectwrapper.cpp
+++ b/src/qml/jsruntime/qv4qobjectwrapper.cpp
@@ -196,8 +196,8 @@ static QV4::ReturnedValue loadProperty(QV4::ExecutionEngine *v4, QObject *object
 }
 
 Heap::QObjectWrapper::QObjectWrapper(QObject *object)
-    : object(object)
 {
+    qObj.init(object);
 }
 
 void QObjectWrapper::initializeBindings(ExecutionEngine *engine)
@@ -210,21 +210,21 @@ QQmlPropertyData *QObjectWrapper::findProperty(ExecutionEngine *engine, QQmlCont
 {
     Q_UNUSED(revisionMode);
 
-    QQmlData *ddata = QQmlData::get(d()->object, false);
+    QQmlData *ddata = QQmlData::get(d()->object(), false);
     if (!ddata)
         return 0;
     QQmlPropertyData *result = 0;
     if (ddata && ddata->propertyCache)
-        result = ddata->propertyCache->property(name, d()->object, qmlContext);
+        result = ddata->propertyCache->property(name, d()->object(), qmlContext);
     else
-        result = QQmlPropertyCache::property(engine->jsEngine(), d()->object, name, qmlContext, *local);
+        result = QQmlPropertyCache::property(engine->jsEngine(), d()->object(), name, qmlContext, *local);
     return result;
 }
 
 ReturnedValue QObjectWrapper::getQmlProperty(QQmlContextData *qmlContext, String *name, QObjectWrapper::RevisionMode revisionMode,
                                              bool *hasProperty, bool includeImports) const
 {
-    if (QQmlData::wasDeleted(d()->object)) {
+    if (QQmlData::wasDeleted(d()->object())) {
         if (hasProperty)
             *hasProperty = false;
         return QV4::Encode::undefined();
@@ -237,7 +237,7 @@ ReturnedValue QObjectWrapper::getQmlProperty(QQmlContextData *qmlContext, String
         if (hasProperty)
             *hasProperty = true;
         ExecutionContext *global = v4->rootContext();
-        return QV4::QObjectMethod::create(global, d()->object, index);
+        return QV4::QObjectMethod::create(global, d()->object(), index);
     }
 
     QQmlPropertyData local;
@@ -256,10 +256,10 @@ ReturnedValue QObjectWrapper::getQmlProperty(QQmlContextData *qmlContext, String
                     if (r.scriptIndex != -1) {
                         return QV4::Encode::undefined();
                     } else if (r.type) {
-                        return QmlTypeWrapper::create(v4, d()->object,
+                        return QmlTypeWrapper::create(v4, d()->object(),
                                                       r.type, Heap::QmlTypeWrapper::ExcludeEnums);
                     } else if (r.importNamespace) {
-                        return QmlTypeWrapper::create(v4, d()->object,
+                        return QmlTypeWrapper::create(v4, d()->object(),
                                                       qmlContext->imports, r.importNamespace, Heap::QmlTypeWrapper::ExcludeEnums);
                     }
                     Q_ASSERT(!"Unreachable");
@@ -269,7 +269,7 @@ ReturnedValue QObjectWrapper::getQmlProperty(QQmlContextData *qmlContext, String
         return QV4::Object::get(this, name, hasProperty);
     }
 
-    QQmlData *ddata = QQmlData::get(d()->object, false);
+    QQmlData *ddata = QQmlData::get(d()->object(), false);
 
     if (revisionMode == QV4::QObjectWrapper::CheckRevision && result->hasRevision()) {
         if (ddata && ddata->propertyCache && !ddata->propertyCache->isAllowedInRevision(result)) {
@@ -282,7 +282,7 @@ ReturnedValue QObjectWrapper::getQmlProperty(QQmlContextData *qmlContext, String
     if (hasProperty)
         *hasProperty = true;
 
-    return getProperty(v4, d()->object, result);
+    return getProperty(v4, d()->object(), result);
 }
 
 ReturnedValue QObjectWrapper::getProperty(ExecutionEngine *engine, QObject *object, QQmlPropertyData *property, bool captureRequired)
@@ -577,7 +577,7 @@ ReturnedValue QObjectWrapper::getProperty(ExecutionEngine *engine, QObject *obje
 
 void QObjectWrapper::setProperty(ExecutionEngine *engine, int propertyIndex, const Value &value)
 {
-    setProperty(engine, d()->object, propertyIndex, value);
+    setProperty(engine, d()->object(), propertyIndex, value);
 }
 
 void QObjectWrapper::setProperty(ExecutionEngine *engine, QObject *object, int propertyIndex, const Value &value)
@@ -630,12 +630,12 @@ void QObjectWrapper::put(Managed *m, String *name, const Value &value)
     QObjectWrapper *that = static_cast<QObjectWrapper*>(m);
     ExecutionEngine *v4 = that->engine();
 
-    if (v4->hasException || QQmlData::wasDeleted(that->d()->object))
+    if (v4->hasException || QQmlData::wasDeleted(that->d()->object()))
         return;
 
     QQmlContextData *qmlContext = v4->callingQmlContext();
-    if (!setQmlProperty(v4, qmlContext, that->d()->object, name, QV4::QObjectWrapper::IgnoreRevision, value)) {
-        QQmlData *ddata = QQmlData::get(that->d()->object);
+    if (!setQmlProperty(v4, qmlContext, that->d()->object(), name, QV4::QObjectWrapper::IgnoreRevision, value)) {
+        QQmlData *ddata = QQmlData::get(that->d()->object());
         // Types created by QML are not extensible at run-time, but for other QObjects we can store them
         // as regular JavaScript properties, like on JavaScript objects.
         if (ddata && ddata->context) {
@@ -673,8 +673,8 @@ void QObjectWrapper::advanceIterator(Managed *m, ObjectIterator *it, Value *name
 
     QObjectWrapper *that = static_cast<QObjectWrapper*>(m);
 
-    if (that->d()->object) {
-        const QMetaObject *mo = that->d()->object->metaObject();
+    if (that->d()->object()) {
+        const QMetaObject *mo = that->d()->object()->metaObject();
         // These indices don't apply to gadgets, so don't block them.
         const bool preventDestruction = mo->superClass() || mo == &QObject::staticMetaObject;
         const int propertyCount = mo->propertyCount();
@@ -944,7 +944,7 @@ void QObjectWrapper::markObjects(Heap::Base *that, QV4::ExecutionEngine *e)
 {
     QObjectWrapper::Data *This = static_cast<QObjectWrapper::Data *>(that);
 
-    if (QObject *o = This->object.data()) {
+    if (QObject *o = This->object()) {
         QQmlVMEMetaObject *vme = QQmlVMEMetaObject::get(o);
         if (vme)
             vme->mark(e);
@@ -966,18 +966,18 @@ void QObjectWrapper::destroyObject(bool lastCall)
     if (!h->internalClass)
         return; // destroyObject already got called
 
-    if (h->object) {
-        QQmlData *ddata = QQmlData::get(h->object, false);
+    if (h->object()) {
+        QQmlData *ddata = QQmlData::get(h->object(), false);
         if (ddata) {
-            if (!h->object->parent() && !ddata->indestructible) {
+            if (!h->object()->parent() && !ddata->indestructible) {
                 if (ddata && ddata->ownContext && ddata->context)
                     ddata->context->emitDestruction();
                 // This object is notionally destroyed now
                 ddata->isQueuedForDeletion = true;
                 if (lastCall)
-                    delete h->object;
+                    delete h->object();
                 else
-                    h->object->deleteLater();
+                    h->object()->deleteLater();
             }
         }
     }
@@ -1677,7 +1677,7 @@ ReturnedValue QObjectMethod::create(ExecutionContext *scope, QObject *object, in
 {
     Scope valueScope(scope);
     Scoped<QObjectMethod> method(valueScope, scope->d()->engine->memoryManager->allocObject<QObjectMethod>(scope));
-    method->d()->object = object;
+    method->d()->setObject(object);
 
     if (QQmlData *ddata = QQmlData::get(object))
         method->d()->propertyCache = ddata->propertyCache;
@@ -1705,7 +1705,7 @@ const QMetaObject *Heap::QObjectMethod::metaObject()
 {
     if (propertyCache)
         return propertyCache->createMetaObject();
-    return object->metaObject();
+    return object()->metaObject();
 }
 
 QV4::ReturnedValue QObjectMethod::method_toString(QV4::ExecutionContext *ctx) const
@@ -1714,10 +1714,10 @@ QV4::ReturnedValue QObjectMethod::method_toString(QV4::ExecutionContext *ctx) co
     if (const QMetaObject *metaObject = d()->metaObject()) {
 
         result += QString::fromUtf8(metaObject->className()) +
-                QLatin1String("(0x") + QString::number((quintptr)d()->object.data(),16);
+                QLatin1String("(0x") + QString::number((quintptr)d()->object(),16);
 
-        if (d()->object) {
-            QString objectName = d()->object->objectName();
+        if (d()->object()) {
+            QString objectName = d()->object()->objectName();
             if (!objectName.isEmpty())
                 result += QLatin1String(", \"") + objectName + QLatin1Char('\"');
         }
@@ -1732,9 +1732,9 @@ QV4::ReturnedValue QObjectMethod::method_toString(QV4::ExecutionContext *ctx) co
 
 QV4::ReturnedValue QObjectMethod::method_destroy(QV4::ExecutionContext *ctx, const Value *args, int argc) const
 {
-    if (!d()->object)
+    if (!d()->object())
         return Encode::undefined();
-    if (QQmlData::keepAliveDuringGarbageCollection(d()->object))
+    if (QQmlData::keepAliveDuringGarbageCollection(d()->object()))
         return ctx->engine()->throwError(QStringLiteral("Invalid attempt to destroy() an indestructible object"));
 
     int delay = 0;
@@ -1742,9 +1742,9 @@ QV4::ReturnedValue QObjectMethod::method_destroy(QV4::ExecutionContext *ctx, con
         delay = args[0].toUInt32();
 
     if (delay > 0)
-        QTimer::singleShot(delay, d()->object, SLOT(deleteLater()));
+        QTimer::singleShot(delay, d()->object(), SLOT(deleteLater()));
     else
-        d()->object->deleteLater();
+        d()->object()->deleteLater();
 
     return Encode::undefined();
 }
@@ -1769,8 +1769,8 @@ void QObjectMethod::callInternal(CallData *callData, Scope &scope) const
         return;
     }
 
-    QQmlObjectOrGadget object(d()->object.data());
-    if (!d()->object) {
+    QQmlObjectOrGadget object(d()->object());
+    if (!d()->object()) {
         if (!d()->valueTypeWrapper) {
             scope.result = Encode::undefined();
             return;
@@ -1789,7 +1789,7 @@ void QObjectMethod::callInternal(CallData *callData, Scope &scope) const
         }
         method = *data;
     } else {
-        const QMetaObject *mo = d()->object->metaObject();
+        const QMetaObject *mo = d()->object()->metaObject();
         const QMetaMethod moMethod = mo->method(d()->index);
         method.load(moMethod);
 
@@ -2014,9 +2014,9 @@ DEFINE_OBJECT_VTABLE(QMetaObjectWrapper);
 
 
 Heap::QmlSignalHandler::QmlSignalHandler(QObject *object, int signalIndex)
-    : object(object)
-    , signalIndex(signalIndex)
+    : signalIndex(signalIndex)
 {
+    setObject(object);
 }
 
 DEFINE_OBJECT_VTABLE(QmlSignalHandler);
diff --git a/src/qml/jsruntime/qv4qobjectwrapper_p.h b/src/qml/jsruntime/qv4qobjectwrapper_p.h
index f0dbd82a63..076f304fea 100644
--- a/src/qml/jsruntime/qv4qobjectwrapper_p.h
+++ b/src/qml/jsruntime/qv4qobjectwrapper_p.h
@@ -79,18 +79,28 @@ struct QQmlValueTypeWrapper;
 
 struct QObjectWrapper : Object {
     QObjectWrapper(QObject *object);
-    QPointer<QObject> object;
+    ~QObjectWrapper() { qObj.destroy(); }
+
+    QObject *object() const { return qObj.data(); }
+
+private:
+    QQmlQPointer<QObject> qObj;
 };
 
 struct QObjectMethod : FunctionObject {
     QObjectMethod(QV4::ExecutionContext *scope);
-    QPointer<QObject> object;
+    ~QObjectMethod() { qObj.destroy(); }
     QQmlRefPointer<QQmlPropertyCache> propertyCache;
     int index;
 
     Pointer<QQmlValueTypeWrapper> valueTypeWrapper;
 
     const QMetaObject *metaObject();
+    QObject *object() const { return qObj.data(); }
+    void setObject(QObject *o) { qObj = o; }
+
+private:
+    QQmlQPointer<QObject> qObj;
 };
 
 struct QMetaObjectWrapper : FunctionObject {
@@ -105,8 +115,14 @@ struct QMetaObjectWrapper : FunctionObject {
 
 struct QmlSignalHandler : Object {
     QmlSignalHandler(QObject *object, int signalIndex);
-    QPointer<QObject> object;
+    ~QmlSignalHandler() { qObj.destroy(); }
     int signalIndex;
+
+    QObject *object() const { return qObj.data(); }
+    void setObject(QObject *o) { qObj = o; }
+
+private:
+    QQmlQPointer<QObject> qObj;
 };
 
 }
@@ -119,7 +135,7 @@ struct Q_QML_EXPORT QObjectWrapper : public Object
 
     static void initializeBindings(ExecutionEngine *engine);
 
-    QObject *object() const { return d()->object.data(); }
+    QObject *object() const { return d()->object(); }
 
     ReturnedValue getQmlProperty(QQmlContextData *qmlContext, String *name, RevisionMode revisionMode, bool *hasProperty = 0, bool includeImports = false) const;
     static ReturnedValue getQmlProperty(ExecutionEngine *engine, QQmlContextData *qmlContext, QObject *object, String *name, RevisionMode revisionMode, bool *hasProperty = 0);
@@ -189,7 +205,7 @@ struct Q_QML_EXPORT QObjectMethod : public QV4::FunctionObject
     static ReturnedValue create(QV4::ExecutionContext *scope, const QQmlValueTypeWrapper *valueType, int index);
 
     int methodIndex() const { return d()->index; }
-    QObject *object() const { return d()->object.data(); }
+    QObject *object() const { return d()->object(); }
 
     QV4::ReturnedValue method_toString(QV4::ExecutionContext *ctx) const;
     QV4::ReturnedValue method_destroy(QV4::ExecutionContext *ctx, const Value *args, int argc) const;
@@ -230,7 +246,7 @@ struct Q_QML_EXPORT QmlSignalHandler : public QV4::Object
     V4_NEEDS_DESTROY
 
     int signalIndex() const { return d()->signalIndex; }
-    QObject *object() const { return d()->object.data(); }
+    QObject *object() const { return d()->object(); }
 
     static void initProto(ExecutionEngine *v4);
 };
diff --git a/src/qml/jsruntime/qv4sequenceobject.cpp b/src/qml/jsruntime/qv4sequenceobject.cpp
index b15ac7eb5e..59086c245c 100644
--- a/src/qml/jsruntime/qv4sequenceobject.cpp
+++ b/src/qml/jsruntime/qv4sequenceobject.cpp
@@ -218,9 +218,10 @@ template <typename Container>
 struct QQmlSequence : Object {
     QQmlSequence(const Container &container);
     QQmlSequence(QObject *object, int propertyIndex);
+    ~QQmlSequence() { object.destroy(); }
 
     mutable Container container;
-    QPointer<QObject> object;
+    QQmlQPointer<QObject> object;
     int propertyIndex;
     bool isReference;
 };
@@ -558,6 +559,8 @@ Heap::QQmlSequence<Container>::QQmlSequence(const Container &container)
     , propertyIndex(-1)
     , isReference(false)
 {
+    object.init();
+
     QV4::Scope scope(internalClass->engine);
     QV4::Scoped<QV4::QQmlSequence<Container> > o(scope, this);
     o->setArrayType(Heap::ArrayData::Custom);
@@ -566,10 +569,10 @@ Heap::QQmlSequence<Container>::QQmlSequence(const Container &container)
 
 template <typename Container>
 Heap::QQmlSequence<Container>::QQmlSequence(QObject *object, int propertyIndex)
-    : object(object)
-    , propertyIndex(propertyIndex)
+    : propertyIndex(propertyIndex)
     , isReference(true)
 {
+    this->object.init(object);
     QV4::Scope scope(internalClass->engine);
     QV4::Scoped<QV4::QQmlSequence<Container> > o(scope, this);
     o->setArrayType(Heap::ArrayData::Custom);
diff --git a/src/qml/memory/qv4heap_p.h b/src/qml/memory/qv4heap_p.h
index ed7a531766..584e8293e5 100644
--- a/src/qml/memory/qv4heap_p.h
+++ b/src/qml/memory/qv4heap_p.h
@@ -52,6 +52,7 @@
 
 #include <QtCore/QString>
 #include <private/qv4global_p.h>
+#include <QSharedPointer>
 
 QT_BEGIN_NAMESPACE
 
@@ -139,6 +140,61 @@ struct Pointer {
 
 }
 
+#ifdef QT_NO_QOBJECT
+template <class T>
+struct QQmlQPointer {
+};
+#else
+template <class T>
+struct QQmlQPointer {
+    void init()
+    {
+        d = nullptr;
+        qObject = nullptr;
+    }
+
+    void init(T *o)
+    {
+        Q_ASSERT(d == nullptr);
+        Q_ASSERT(qObject == nullptr);
+        if (o) {
+            d = QtSharedPointer::ExternalRefCountData::getAndRef(o);
+            qObject = o;
+        }
+    }
+
+    void destroy()
+    {
+        if (d && !d->weakref.deref())
+            delete d;
+        d = nullptr;
+        qObject = nullptr;
+    }
+
+    T *data() const {
+        return d == nullptr || d->strongref.load() == 0 ? nullptr : qObject;
+    }
+    operator T*() const { return data(); }
+    inline T* operator->() const { return data(); }
+    QQmlQPointer &operator=(T *o)
+    {
+        if (d)
+            destroy();
+        init(o);
+        return *this;
+    }
+    bool isNull() const Q_DECL_NOTHROW
+    {
+        return d == nullptr || qObject == nullptr || d->strongref.load() == 0;
+    }
+
+private:
+    QtSharedPointer::ExternalRefCountData *d;
+    QObject *qObject;
+};
+Q_STATIC_ASSERT(std::is_trivial<QQmlQPointer<QObject>>::value);
+#endif
+
 }
 
 QT_END_NAMESPACE
diff --git a/src/qml/qml/qqmlcomponent.cpp b/src/qml/qml/qqmlcomponent.cpp
index 5a440bdaf4..337b15d35c 100644
--- a/src/qml/qml/qqmlcomponent.cpp
+++ b/src/qml/qml/qqmlcomponent.cpp
@@ -1059,8 +1059,9 @@ namespace Heap {
 
 struct QmlIncubatorObject : Object {
     QmlIncubatorObject(QQmlIncubator::IncubationMode = QQmlIncubator::Asynchronous);
+    ~QmlIncubatorObject() { parent.destroy(); }
     QScopedPointer<QQmlComponentIncubator> incubator;
-    QPointer<QObject> parent;
+    QQmlQPointer<QObject> parent;
     QV4::Value valuemap;
     QV4::Value statusChanged;
     Pointer<Heap::QmlContext> qmlContext;
@@ -1488,6 +1489,7 @@ QV4::Heap::QmlIncubatorObject::QmlIncubatorObject(QQmlIncubator::IncubationMode
     , statusChanged(QV4::Primitive::undefinedValue())
     , qmlContext(0)
 {
+    parent.init();
     incubator.reset(new QQmlComponentIncubator(this, m));
 }
 
diff --git a/src/qml/qml/qqmlcontextwrapper.cpp b/src/qml/qml/qqmlcontextwrapper.cpp
index 2d0ebad764..13d708bc17 100644
--- a/src/qml/qml/qqmlcontextwrapper.cpp
+++ b/src/qml/qml/qqmlcontextwrapper.cpp
@@ -66,14 +66,15 @@ Heap::QmlContextWrapper::QmlContextWrapper(QQmlContextData *context, QObject *sc
     , ownsContext(ownsContext)
     , isNullWrapper(false)
     , context(context)
-    , scopeObject(scopeObject)
 {
+    this->scopeObject.init(scopeObject);
 }
 
 Heap::QmlContextWrapper::~QmlContextWrapper()
 {
     if (context && ownsContext)
         context->destroy();
+    scopeObject.destroy();
 }
 
 ReturnedValue QmlContextWrapper::qmlScope(ExecutionEngine *v4, QQmlContextData *ctxt, QObject *scope)
diff --git a/src/qml/qml/qqmlcontextwrapper_p.h b/src/qml/qml/qqmlcontextwrapper_p.h
index ca7fcf1d75..2b8c16f274 100644
--- a/src/qml/qml/qqmlcontextwrapper_p.h
+++ b/src/qml/qml/qqmlcontextwrapper_p.h
@@ -71,7 +71,7 @@ struct QmlContextWrapper : Object {
     bool isNullWrapper;
 
     QQmlGuardedContextData context;
-    QPointer<QObject> scopeObject;
+    QQmlQPointer<QObject> scopeObject;
 };
 
 }
diff --git a/src/qml/qml/qqmllistwrapper.cpp b/src/qml/qml/qqmllistwrapper.cpp
index 5c35866274..425a720867 100644
--- a/src/qml/qml/qqmllistwrapper.cpp
+++ b/src/qml/qml/qqmllistwrapper.cpp
@@ -54,6 +54,7 @@ DEFINE_OBJECT_VTABLE(QmlListWrapper);
 
 Heap::QmlListWrapper::QmlListWrapper()
 {
+    object.init();
     QV4::Scope scope(internalClass->engine);
     QV4::ScopedObject o(scope, this);
     o->setArrayType(Heap::ArrayData::Custom);
@@ -61,6 +62,7 @@ Heap::QmlListWrapper::QmlListWrapper()
 
 Heap::QmlListWrapper::~QmlListWrapper()
 {
+    object.destroy();
 }
 
 ReturnedValue QmlListWrapper::create(ExecutionEngine *engine, QObject *object, int propId, int propType)
diff --git a/src/qml/qml/qqmllistwrapper_p.h b/src/qml/qml/qqmllistwrapper_p.h
index 26e1e5faaf..1107b957c9 100644
--- a/src/qml/qml/qqmllistwrapper_p.h
+++ b/src/qml/qml/qqmllistwrapper_p.h
@@ -68,7 +68,7 @@ namespace Heap {
 struct QmlListWrapper : Object {
     QmlListWrapper();
     ~QmlListWrapper();
-    QPointer<QObject> object;
+    QQmlQPointer<QObject> object;
     QQmlListProperty<QObject> property;
     int propertyType;
 };
diff --git a/src/qml/qml/qqmltypewrapper.cpp b/src/qml/qml/qqmltypewrapper.cpp
index 7892555f08..28c2588117 100644
--- a/src/qml/qml/qqmltypewrapper.cpp
+++ b/src/qml/qml/qqmltypewrapper.cpp
@@ -58,12 +58,14 @@ DEFINE_OBJECT_VTABLE(QmlTypeWrapper);
 Heap::QmlTypeWrapper::QmlTypeWrapper()
     : mode(IncludeEnums)
 {
+    object.init();
 }
 
 Heap::QmlTypeWrapper::~QmlTypeWrapper()
 {
     if (typeNamespace)
         typeNamespace->release();
+    object.destroy();
 }
 
 bool QmlTypeWrapper::isSingleton() const
diff --git a/src/qml/qml/qqmltypewrapper_p.h b/src/qml/qml/qqmltypewrapper_p.h
index 8216526cb5..7c5105b184 100644
--- a/src/qml/qml/qqmltypewrapper_p.h
+++ b/src/qml/qml/qqmltypewrapper_p.h
@@ -74,7 +74,7 @@ struct QmlTypeWrapper : Object {
     QmlTypeWrapper();
     ~QmlTypeWrapper();
     TypeNameMode mode;
-    QPointer<QObject> object;
+    QQmlQPointer<QObject> object;
 
     QQmlType *type;
     QQmlTypeNameCache *typeNamespace;
diff --git a/src/qml/qml/qqmlvaluetypewrapper.cpp b/src/qml/qml/qqmlvaluetypewrapper.cpp
index 2566ab06b5..6b308374e6 100644
--- a/src/qml/qml/qqmlvaluetypewrapper.cpp
+++ b/src/qml/qml/qqmlvaluetypewrapper.cpp
@@ -63,8 +63,9 @@ namespace Heap {
 
 struct QQmlValueTypeReference : QQmlValueTypeWrapper
 {
-    QQmlValueTypeReference() {}
-    QPointer<QObject> object;
+    QQmlValueTypeReference() { object.init(); }
+    ~QQmlValueTypeReference() { object.destroy(); }
+    QQmlQPointer<QObject> object;
     int property;
 };