QML: Specialize bindings based on target property type.

When we can determine the type of a target property during type
compilation, we can skip a whole bunch of code that deals with
converting the result of a binding to the correct (target) type.

This removes 65 instructions on x86 for such typed bindings.

Change-Id: Id2c7c57b9ae6dfbeb921121beae9630604ca1d17
Reviewed-by: Simon Hausmann <simon.hausmann@qt.io>

13 files changed, 294 insertions, 131 deletions

diff --git a/src/plugins/qmltooling/qmldbg_debugger/qqmlenginedebugservice.cpp b/src/plugins/qmltooling/qmldbg_debugger/qqmlenginedebugservice.cpp
index 209aa6eda6..e49b15218e 100644
--- a/src/plugins/qmltooling/qmldbg_debugger/qqmlenginedebugservice.cpp
+++ b/src/plugins/qmltooling/qmldbg_debugger/qqmlenginedebugservice.cpp
@@ -656,7 +656,7 @@ bool QQmlEngineDebugServiceImpl::setBinding(int objectId,
                                                                                              filename, line, column);
                     QQmlPropertyPrivate::takeSignalExpression(property, qmlExpression);
                 } else if (property.isProperty()) {
-                    QQmlBinding *binding = new QQmlBinding(expression.toString(), object, QQmlContextData::get(context), filename, line, column);
+                    QQmlBinding *binding = QQmlBinding::create(&QQmlPropertyPrivate::get(property)->core, expression.toString(), object, QQmlContextData::get(context), filename, line, column);
                     binding->setTarget(property);
                     QQmlPropertyPrivate::setBinding(binding);
                     binding->update();
diff --git a/src/qml/jsruntime/qv4qobjectwrapper.cpp b/src/qml/jsruntime/qv4qobjectwrapper.cpp
index deed9b86a2..cf99b425a2 100644
--- a/src/qml/jsruntime/qv4qobjectwrapper.cpp
+++ b/src/qml/jsruntime/qv4qobjectwrapper.cpp
@@ -465,7 +465,7 @@ void QObjectWrapper::setProperty(ExecutionEngine *engine, QObject *object, QQmlP
             QV4::Scoped<QQmlBindingFunction> bindingFunction(scope, (const Value &)f);
             bindingFunction->initBindingLocation();
 
-            newBinding = new QQmlBinding(value, object, callingQmlContext);
+            newBinding = QQmlBinding::create(property, value, object, callingQmlContext);
             newBinding->setTarget(object, *property);
         }
     }
diff --git a/src/qml/jsruntime/qv4scopedvalue_p.h b/src/qml/jsruntime/qv4scopedvalue_p.h
index aa811ddba4..44d171e087 100644
--- a/src/qml/jsruntime/qv4scopedvalue_p.h
+++ b/src/qml/jsruntime/qv4scopedvalue_p.h
@@ -294,6 +294,10 @@ struct Scoped
         return ptr->cast<T>();
     }
 
+    const T *operator->() const {
+        return ptr->cast<T>();
+    }
+
     bool operator!() const {
         return !ptr->m();
     }
diff --git a/src/qml/qml/qqmlbinding.cpp b/src/qml/qml/qqmlbinding.cpp
index 3940176107..9f86e448ef 100644
--- a/src/qml/qml/qqmlbinding.cpp
+++ b/src/qml/qml/qqmlbinding.cpp
@@ -56,27 +56,28 @@
 
 QT_BEGIN_NAMESPACE
 
-QQmlBinding::QQmlBinding(const QString &str, QObject *obj, QQmlContext *ctxt)
-    : QQmlJavaScriptExpression(),
-      QQmlAbstractBinding()
+QQmlBinding *QQmlBinding::create(const QQmlPropertyData *property, const QString &str, QObject *obj, QQmlContext *ctxt)
 {
-    setNotifyOnValueChanged(true);
-    QQmlJavaScriptExpression::setContext(QQmlContextData::get(ctxt));
-    setScopeObject(obj);
+    QQmlBinding *b = newBinding(property);
+    b->setNotifyOnValueChanged(true);
+    b->QQmlJavaScriptExpression::setContext(QQmlContextData::get(ctxt));
+    b->setScopeObject(obj);
 
-    createQmlBinding(context(), obj, str, QString(), 0);
+    b->createQmlBinding(b->context(), obj, str, QString(), 0);
+
+    return b;
 }
 
-QQmlBinding::QQmlBinding(const QQmlScriptString &script, QObject *obj, QQmlContext *ctxt)
-    : QQmlJavaScriptExpression(),
-      QQmlAbstractBinding()
+QQmlBinding *QQmlBinding::create(const QQmlPropertyData *property, const QQmlScriptString &script, QObject *obj, QQmlContext *ctxt)
 {
+    QQmlBinding *b = newBinding(property);
+
     if (ctxt && !ctxt->isValid())
-        return;
+        return b;
 
     const QQmlScriptStringPrivate *scriptPrivate = script.d.data();
     if (!ctxt && (!scriptPrivate->context || !scriptPrivate->context->isValid()))
-        return;
+        return b;
 
     QString url;
     QV4::Function *runtimeFunction = 0;
@@ -89,53 +90,61 @@ QQmlBinding::QQmlBinding(const QQmlScriptString &script, QObject *obj, QQmlConte
             runtimeFunction = ctxtdata->typeCompilationUnit->runtimeFunctions.at(scriptPrivate->bindingId);
     }
 
-    setNotifyOnValueChanged(true);
-    QQmlJavaScriptExpression::setContext(QQmlContextData::get(ctxt ? ctxt : scriptPrivate->context));
-    setScopeObject(obj ? obj : scriptPrivate->scope);
+    b->setNotifyOnValueChanged(true);
+    b->QQmlJavaScriptExpression::setContext(QQmlContextData::get(ctxt ? ctxt : scriptPrivate->context));
+    b->setScopeObject(obj ? obj : scriptPrivate->scope);
 
-    QV4::ExecutionEngine *v4 = QQmlEnginePrivate::get(context()->engine)->v4engine();
+    QV4::ExecutionEngine *v4 = QQmlEnginePrivate::get(b->context()->engine)->v4engine();
     if (runtimeFunction) {
-        m_function.set(v4, QV4::FunctionObject::createQmlFunction(ctxtdata, scopeObject(), runtimeFunction));
+        b->m_function.set(v4, QV4::FunctionObject::createQmlFunction(ctxtdata, b->scopeObject(), runtimeFunction));
     } else {
         QString code = scriptPrivate->script;
-        createQmlBinding(context(), scopeObject(), code, url, scriptPrivate->lineNumber);
+        b->createQmlBinding(b->context(), b->scopeObject(), code, url, scriptPrivate->lineNumber);
     }
+
+    return b;
 }
 
-QQmlBinding::QQmlBinding(const QString &str, QObject *obj, QQmlContextData *ctxt)
-    : QQmlJavaScriptExpression(),
-      QQmlAbstractBinding()
+QQmlBinding *QQmlBinding::create(const QQmlPropertyData *property, const QString &str, QObject *obj, QQmlContextData *ctxt)
 {
-    setNotifyOnValueChanged(true);
-    QQmlJavaScriptExpression::setContext(ctxt);
-    setScopeObject(obj);
+    QQmlBinding *b = newBinding(property);
+
+    b->setNotifyOnValueChanged(true);
+    b->QQmlJavaScriptExpression::setContext(ctxt);
+    b->setScopeObject(obj);
 
-    createQmlBinding(ctxt, obj, str, QString(), 0);
+    b->createQmlBinding(ctxt, obj, str, QString(), 0);
+
+    return b;
 }
 
-QQmlBinding::QQmlBinding(const QString &str, QObject *obj,
-                         QQmlContextData *ctxt,
-                         const QString &url, quint16 lineNumber, quint16 columnNumber)
-    : QQmlJavaScriptExpression(),
-      QQmlAbstractBinding()
+QQmlBinding *QQmlBinding::create(const QQmlPropertyData *property, const QString &str, QObject *obj,
+                                 QQmlContextData *ctxt, const QString &url, quint16 lineNumber,
+                                 quint16 columnNumber)
 {
+    QQmlBinding *b = newBinding(property);
+
     Q_UNUSED(columnNumber);
-    setNotifyOnValueChanged(true);
-    QQmlJavaScriptExpression::setContext(ctxt);
-    setScopeObject(obj);
+    b->setNotifyOnValueChanged(true);
+    b->QQmlJavaScriptExpression::setContext(ctxt);
+    b->setScopeObject(obj);
+
+    b->createQmlBinding(ctxt, obj, str, url, lineNumber);
 
-    createQmlBinding(ctxt, obj, str, url, lineNumber);
+    return b;
 }
 
-QQmlBinding::QQmlBinding(const QV4::Value &functionPtr, QObject *obj, QQmlContextData *ctxt)
-    : QQmlJavaScriptExpression(),
-      QQmlAbstractBinding()
+QQmlBinding *QQmlBinding::create(const QQmlPropertyData *property, const QV4::Value &functionPtr, QObject *obj, QQmlContextData *ctxt)
 {
-    setNotifyOnValueChanged(true);
-    QQmlJavaScriptExpression::setContext(ctxt);
-    setScopeObject(obj);
+    QQmlBinding *b = newBinding(property);
 
-    m_function.set(functionPtr.as<QV4::Object>()->engine(), functionPtr);
+    b->setNotifyOnValueChanged(true);
+    b->QQmlJavaScriptExpression::setContext(ctxt);
+    b->setScopeObject(obj);
+
+    b->m_function.set(functionPtr.as<QV4::Object>()->engine(), functionPtr);
+
+    return b;
 }
 
 QQmlBinding::~QQmlBinding()
@@ -156,45 +165,86 @@ void QQmlBinding::update(QQmlPropertyPrivate::WriteFlags flags)
     if (QQmlData::wasDeleted(targetObject()))
         return;
 
-    QQmlEnginePrivate *ep = QQmlEnginePrivate::get(context()->engine);
-    QV4::Scope scope(ep->v4engine());
-    QV4::ScopedFunctionObject f(scope, m_function.value());
-    Q_ASSERT(f);
-
-    if (updatingFlag()) {
+    // Check for a binding update loop
+    if (Q_UNLIKELY(updatingFlag())) {
         QQmlProperty p = QQmlPropertyPrivate::restore(targetObject(), getPropertyData(), 0);
         QQmlAbstractBinding::printBindingLoopError(p);
         return;
     }
-
-    QQmlBindingProfiler prof(ep->profiler, this, f);
     setUpdatingFlag(true);
 
-    QQmlJavaScriptExpression::DeleteWatcher watcher(this);
+    DeleteWatcher watcher(this);
 
-    QQmlPropertyData pd = getPropertyData();
+    QQmlEnginePrivate *ep = QQmlEnginePrivate::get(context()->engine);
+    QV4::Scope scope(ep->v4engine());
+    QV4::ScopedFunctionObject f(scope, m_function.value());
+    Q_ASSERT(f);
 
-    if (pd.propType == qMetaTypeId<QQmlBinding *>()) {
+    QQmlBindingProfiler prof(ep->profiler, this, f);
+    doUpdate(this, watcher, flags, scope, f);
+
+    if (!watcher.wasDeleted())
+        setUpdatingFlag(false);
+}
+
+// QQmlBindingBinding is for target properties which are of type "binding" (instead of, say, int or
+// double). The reason for being is that GenericBinding::fastWrite needs a compile-time constant
+// expression for the switch for the compiler to generate the optimal code, but
+// qMetaTypeId<QQmlBinding *>() needs to be used for the ID. So QQmlBinding::newBinding uses that
+// to instantiate this class.
+class QQmlBindingBinding: public QQmlBinding
+{
+protected:
+    void doUpdate(QQmlBinding *binding, const DeleteWatcher &,
+                  QQmlPropertyPrivate::WriteFlags flags, QV4::Scope &,
+                  const QV4::ScopedFunctionObject &) Q_DECL_OVERRIDE Q_DECL_FINAL
+    {
+        QQmlPropertyData pd = getPropertyData();
 
         int idx = pd.coreIndex;
         Q_ASSERT(idx != -1);
 
-        QQmlBinding *t = this;
         int status = -1;
-        void *a[] = { &t, 0, &status, &flags };
+        void *a[] = { &binding, 0, &status, &flags };
         QMetaObject::metacall(*m_target, QMetaObject::WriteProperty, idx, a);
+    }
+};
 
-    } else {
+#define QUICK_STORE(cpptype, conversion) \
+        { \
+            cpptype o = (conversion); \
+            int status = -1; \
+            void *argv[] = { &o, 0, &status, &flags }; \
+            QMetaObject::metacall(m_target.data(), QMetaObject::WriteProperty, coreIndex, argv); \
+            return true; \
+        } \
+
+
+template<int StaticPropType>
+class GenericBinding: public QQmlBinding
+{
+protected:
+
+    void doUpdate(QQmlBinding *binding, const DeleteWatcher &watcher,
+                  QQmlPropertyPrivate::WriteFlags flags, QV4::Scope &scope,
+                  const QV4::ScopedFunctionObject &f) Q_DECL_OVERRIDE Q_DECL_FINAL
+    {
+        auto ep = QQmlEnginePrivate::get(scope.engine);
         ep->referenceScarceResources();
 
         bool isUndefined = false;
 
         QV4::ScopedCallData callData(scope);
-        QQmlJavaScriptExpression::evaluate(callData, &isUndefined, scope);
+        binding->QQmlJavaScriptExpression::evaluate(callData, &isUndefined, scope);
 
         bool error = false;
-        if (!watcher.wasDeleted() && isAddedToObject() && !hasError())
-            error = !write(pd, scope.result, isUndefined, flags);
+        if (!watcher.wasDeleted() && isAddedToObject() && !hasError()) {
+            if (StaticPropType == QMetaType::UnknownType) {
+                error = !write(scope.result, isUndefined, flags);
+            } else {
+                error = !fastWrite(scope.result, isUndefined, flags);
+            }
+        }
 
         if (!watcher.wasDeleted()) {
 
@@ -214,30 +264,62 @@ void QQmlBinding::update(QQmlPropertyPrivate::WriteFlags flags)
         ep->dereferenceScarceResources();
     }
 
-    if (!watcher.wasDeleted())
-        setUpdatingFlag(false);
-}
+private:
+    // Returns true if successful, false if an error description was set on expression
+    Q_ALWAYS_INLINE bool fastWrite(const QV4::Value &result, bool isUndefined,
+                                   QQmlPropertyPrivate::WriteFlags flags)
+    {
+        int coreIndex = getPropertyCoreIndex();
+
+        Q_ASSERT(m_target.data());
+
+        if (Q_LIKELY(!isUndefined && coreIndex != -1 )) {
+            switch (StaticPropType) {
+            case QMetaType::Int:
+                if (result.isInteger())
+                    QUICK_STORE(int, result.integerValue())
+                else if (result.isNumber())
+                    QUICK_STORE(int, result.doubleValue())
+                break;
+            case QMetaType::Double:
+                if (result.isNumber())
+                    QUICK_STORE(double, result.asDouble())
+                break;
+            case QMetaType::Float:
+                if (result.isNumber())
+                    QUICK_STORE(float, result.asDouble())
+                break;
+            case QMetaType::QString:
+                if (result.isString())
+                    QUICK_STORE(QString, result.toQStringNoThrow())
+                break;
+            default:
+                if (const QV4::QQmlValueTypeWrapper *vtw = result.as<const QV4::QQmlValueTypeWrapper>()) {
+                    if (vtw->d()->valueType->typeId == StaticPropType) {
+                        return vtw->write(m_target.data(), coreIndex);
+                    }
+                }
+                break;
+            }
+        }
+
+        return slowWrite(result, isUndefined, flags);
+    }
+};
 
 // Returns true if successful, false if an error description was set on expression
-bool QQmlBinding::write(const QQmlPropertyData &core,
-                       const QV4::Value &result, bool isUndefined,
-                       QQmlPropertyPrivate::WriteFlags flags)
+Q_ALWAYS_INLINE bool QQmlBinding::write(const QV4::Value &result, bool isUndefined,
+                                        QQmlPropertyPrivate::WriteFlags flags)
 {
     Q_ASSERT(m_target.data());
-    Q_ASSERT(core.coreIndex != -1);
 
-#define QUICK_STORE(cpptype, conversion) \
-        { \
-            cpptype o = (conversion); \
-            int status = -1; \
-            void *argv[] = { &o, 0, &status, &flags }; \
-            QMetaObject::metacall(m_target.data(), QMetaObject::WriteProperty, core.coreIndex, argv); \
-            return true; \
-        } \
+    int coreIndex = getPropertyCoreIndex();
+    int propertyType = getPropertyType();
 
+    Q_ASSERT(m_target.data());
 
-    if (Q_LIKELY(!isUndefined && !core.isValueTypeVirtual())) {
-        switch (core.propType) {
+    if (Q_LIKELY(!isUndefined && coreIndex != -1 )) {
+        switch (propertyType) {
         case QMetaType::Int:
             if (result.isInteger())
                 QUICK_STORE(int, result.integerValue())
@@ -258,15 +340,23 @@ bool QQmlBinding::write(const QQmlPropertyData &core,
             break;
         default:
             if (const QV4::QQmlValueTypeWrapper *vtw = result.as<const QV4::QQmlValueTypeWrapper>()) {
-                if (vtw->d()->valueType->typeId == core.propType) {
-                    return vtw->write(m_target.data(), core.coreIndex);
+                if (vtw->d()->valueType->typeId == propertyType) {
+                    return vtw->write(m_target.data(), coreIndex);
                 }
             }
             break;
         }
     }
+
+    return slowWrite(result, isUndefined, flags);
+}
 #undef QUICK_STORE
 
+Q_NEVER_INLINE bool QQmlBinding::slowWrite(const QV4::Value &result, bool isUndefined,
+                                           QQmlPropertyPrivate::WriteFlags flags)
+{
+    QQmlPropertyData core = getPropertyData();
+
     QQmlEngine *engine = context()->engine;
     QV8Engine *v8engine = QQmlEnginePrivate::getV8Engine(engine);
 
@@ -510,4 +600,51 @@ QQmlPropertyData QQmlBinding::getPropertyData() const
     return d;
 }
 
+Q_ALWAYS_INLINE int QQmlBinding::getPropertyCoreIndex() const
+{
+    int coreIndex;
+    int valueTypeIndex = QQmlPropertyData::decodeValueTypePropertyIndex(m_targetIndex, &coreIndex);
+    if (valueTypeIndex != -1) {
+        return -1;
+    } else {
+        return coreIndex;
+    }
+}
+
+int QQmlBinding::getPropertyType() const
+{
+    int coreIndex;
+    int valueTypeIndex = QQmlPropertyData::decodeValueTypePropertyIndex(m_targetIndex, &coreIndex);
+
+    QQmlData *data = QQmlData::get(*m_target, false);
+    Q_ASSERT(data && data->propertyCache);
+
+    QQmlPropertyData *propertyData = data->propertyCache->property(coreIndex);
+    Q_ASSERT(propertyData);
+
+    if (valueTypeIndex == -1)
+        return propertyData->propType;
+    else
+        return QMetaType::UnknownType;
+}
+
+QQmlBinding *QQmlBinding::newBinding(const QQmlPropertyData *property)
+{
+    const int type = (property && property->isFullyResolved()) ? property->propType : QMetaType::UnknownType;
+
+    if (type == qMetaTypeId<QQmlBinding *>()) {
+        return new QQmlBindingBinding;
+    } else if (type == QMetaType::Int) {
+        return new GenericBinding<QMetaType::Int>;
+    } else if (type == QMetaType::Double) {
+        return new GenericBinding<QMetaType::Double>;
+    } else if (type == QMetaType::Float) {
+        return new GenericBinding<QMetaType::Float>;
+    } else if (type == QMetaType::QString) {
+        return new GenericBinding<QMetaType::QString>;
+    } else {
+        return new GenericBinding<QMetaType::UnknownType>;
+    }
+}
+
 QT_END_NAMESPACE
diff --git a/src/qml/qml/qqmlbinding_p.h b/src/qml/qml/qqmlbinding_p.h
index 45c360f07e..ad1b24f340 100644
--- a/src/qml/qml/qqmlbinding_p.h
+++ b/src/qml/qml/qqmlbinding_p.h
@@ -72,12 +72,12 @@ class Q_QML_PRIVATE_EXPORT QQmlBinding : public QQmlJavaScriptExpression,
 {
     friend class QQmlAbstractBinding;
 public:
-    QQmlBinding(const QString &, QObject *, QQmlContext *);
-    QQmlBinding(const QQmlScriptString &, QObject *, QQmlContext *);
-    QQmlBinding(const QString &, QObject *, QQmlContextData *);
-    QQmlBinding(const QString &, QObject *, QQmlContextData *,
-                const QString &url, quint16 lineNumber, quint16 columnNumber);
-    QQmlBinding(const QV4::Value &, QObject *, QQmlContextData *);
+    static QQmlBinding *create(const QQmlPropertyData *, const QString &, QObject *, QQmlContext *);
+    static QQmlBinding *create(const QQmlPropertyData *, const QQmlScriptString &, QObject *, QQmlContext *);
+    static QQmlBinding *create(const QQmlPropertyData *, const QString &, QObject *, QQmlContextData *);
+    static QQmlBinding *create(const QQmlPropertyData *, const QString &, QObject *, QQmlContextData *,
+                               const QString &url, quint16 lineNumber, quint16 columnNumber);
+    static QQmlBinding *create(const QQmlPropertyData *, const QV4::Value &, QObject *, QQmlContextData *);
     ~QQmlBinding();
 
     void setTarget(const QQmlProperty &);
@@ -101,17 +101,27 @@ public:
     QString expressionIdentifier() Q_DECL_OVERRIDE;
     void expressionChanged() Q_DECL_OVERRIDE;
 
+protected:
+    virtual void doUpdate(QQmlBinding *binding, const DeleteWatcher &watcher,
+                          QQmlPropertyPrivate::WriteFlags flags, QV4::Scope &scope,
+                          const QV4::ScopedFunctionObject &f) = 0;
+
+    QQmlPropertyData getPropertyData() const;
+    int getPropertyCoreIndex() const;
+    int getPropertyType() const;
+
+    bool write(const QV4::Value &result, bool isUndefined, QQmlPropertyPrivate::WriteFlags flags);
+
+    bool slowWrite(const QV4::Value &result, bool isUndefined,
+                   QQmlPropertyPrivate::WriteFlags flags);
+
 private:
     inline bool updatingFlag() const;
     inline void setUpdatingFlag(bool);
     inline bool enabledFlag() const;
     inline void setEnabledFlag(bool);
-    QQmlPropertyData getPropertyData() const;
-
-    bool write(const QQmlPropertyData &core,
-                       const QV4::Value &result, bool isUndefined,
-                       QQmlPropertyPrivate::WriteFlags flags);
 
+    static QQmlBinding *newBinding(const QQmlPropertyData *property);
 };
 
 bool QQmlBinding::updatingFlag() const
diff --git a/src/qml/qml/qqmlobjectcreator.cpp b/src/qml/qml/qqmlobjectcreator.cpp
index 6a54555f3f..2e2d87509a 100644
--- a/src/qml/qml/qqmlobjectcreator.cpp
+++ b/src/qml/qml/qqmlobjectcreator.cpp
@@ -813,8 +813,6 @@ bool QQmlObjectCreator::setPropertyBinding(const QQmlPropertyData *property, con
 
             bs->takeExpression(expr);
         } else {
-            QQmlBinding *qmlBinding = new QQmlBinding(function, _scopeObject, context);
-
             // When writing bindings to grouped properties implemented as value types,
             // such as point.x: { someExpression; }, then the binding is installed on
             // the point property (_qobjectForBindings) and after evaluating the expression,
@@ -824,6 +822,7 @@ bool QQmlObjectCreator::setPropertyBinding(const QQmlPropertyData *property, con
             if (_valueTypeProperty)
                 targetCorePropertyData = QQmlPropertyPrivate::saveValueType(*_valueTypeProperty, _qobject->metaObject(), property->coreIndex, engine);
 
+            QQmlBinding *qmlBinding = QQmlBinding::create(&targetCorePropertyData, function, _scopeObject, context);
             sharedState->allCreatedBindings.push(QQmlAbstractBinding::Ptr(qmlBinding));
 
             qmlBinding->setTarget(_bindingTarget, targetCorePropertyData);
diff --git a/src/qml/qml/qqmlvaluetypewrapper.cpp b/src/qml/qml/qqmlvaluetypewrapper.cpp
index 5cb346a462..b69eea61c5 100644
--- a/src/qml/qml/qqmlvaluetypewrapper.cpp
+++ b/src/qml/qml/qqmlvaluetypewrapper.cpp
@@ -459,7 +459,7 @@ void QQmlValueTypeWrapper::put(Managed *m, String *name, const Value &value)
             QV4::Scoped<QQmlBindingFunction> bindingFunction(scope, (const Value &)f);
             bindingFunction->initBindingLocation();
 
-            QQmlBinding *newBinding = new QQmlBinding(value, reference->d()->object, context);
+            QQmlBinding *newBinding = QQmlBinding::create(&cacheData, value, reference->d()->object, context);
             newBinding->setTarget(reference->d()->object, cacheData);
             QQmlPropertyPrivate::setBinding(newBinding);
             return;
diff --git a/src/quick/designer/qquickdesignercustomobjectdata.cpp b/src/quick/designer/qquickdesignercustomobjectdata.cpp
index 93e7b6133f..42dcb08d45 100644
--- a/src/quick/designer/qquickdesignercustomobjectdata.cpp
+++ b/src/quick/designer/qquickdesignercustomobjectdata.cpp
@@ -257,7 +257,8 @@ void QQuickDesignerCustomObjectData::setPropertyBinding(QQmlContext *context,
         return;
 
     if (property.isProperty()) {
-        QQmlBinding *binding = new QQmlBinding(expression, object(), context);
+        QQmlBinding *binding = QQmlBinding::create(&QQmlPropertyPrivate::get(property)->core,
+                                                   expression, object(), context);
         binding->setTarget(property);
         binding->setNotifyOnValueChanged(true);
 
diff --git a/src/quick/items/qquickstateoperations.cpp b/src/quick/items/qquickstateoperations.cpp
index 73b1680305..7e485c675c 100644
--- a/src/quick/items/qquickstateoperations.cpp
+++ b/src/quick/items/qquickstateoperations.cpp
@@ -359,8 +359,8 @@ QQuickStateOperation::ActionList QQuickParentChange::actions()
             QQuickStateAction xa(d->target, QLatin1String("x"), x);
             actions << xa;
         } else {
-            QQmlBinding *newBinding = new QQmlBinding(d->xString.value, d->target, qmlContext(this));
             QQmlProperty property(d->target, QLatin1String("x"));
+            QQmlBinding *newBinding = QQmlBinding::create(&QQmlPropertyPrivate::get(property)->core, d->xString.value, d->target, qmlContext(this));
             newBinding->setTarget(property);
             QQuickStateAction xa;
             xa.property = property;
@@ -378,8 +378,8 @@ QQuickStateOperation::ActionList QQuickParentChange::actions()
             QQuickStateAction ya(d->target, QLatin1String("y"), y);
             actions << ya;
         } else {
-            QQmlBinding *newBinding = new QQmlBinding(d->yString.value, d->target, qmlContext(this));
             QQmlProperty property(d->target, QLatin1String("y"));
+            QQmlBinding *newBinding = QQmlBinding::create(&QQmlPropertyPrivate::get(property)->core, d->yString.value, d->target, qmlContext(this));
             newBinding->setTarget(property);
             QQuickStateAction ya;
             ya.property = property;
@@ -397,8 +397,8 @@ QQuickStateOperation::ActionList QQuickParentChange::actions()
             QQuickStateAction sa(d->target, QLatin1String("scale"), scale);
             actions << sa;
         } else {
-            QQmlBinding *newBinding = new QQmlBinding(d->scaleString.value, d->target, qmlContext(this));
             QQmlProperty property(d->target, QLatin1String("scale"));
+            QQmlBinding *newBinding = QQmlBinding::create(&QQmlPropertyPrivate::get(property)->core, d->scaleString.value, d->target, qmlContext(this));
             newBinding->setTarget(property);
             QQuickStateAction sa;
             sa.property = property;
@@ -416,8 +416,8 @@ QQuickStateOperation::ActionList QQuickParentChange::actions()
             QQuickStateAction ra(d->target, QLatin1String("rotation"), rotation);
             actions << ra;
         } else {
-            QQmlBinding *newBinding = new QQmlBinding(d->rotationString.value, d->target, qmlContext(this));
             QQmlProperty property(d->target, QLatin1String("rotation"));
+            QQmlBinding *newBinding = QQmlBinding::create(&QQmlPropertyPrivate::get(property)->core, d->rotationString.value, d->target, qmlContext(this));
             newBinding->setTarget(property);
             QQuickStateAction ra;
             ra.property = property;
@@ -435,8 +435,8 @@ QQuickStateOperation::ActionList QQuickParentChange::actions()
             QQuickStateAction wa(d->target, QLatin1String("width"), width);
             actions << wa;
         } else {
-            QQmlBinding *newBinding = new QQmlBinding(d->widthString.value, d->target, qmlContext(this));
             QQmlProperty property(d->target, QLatin1String("width"));
+            QQmlBinding *newBinding = QQmlBinding::create(&QQmlPropertyPrivate::get(property)->core, d->widthString.value, d->target, qmlContext(this));
             newBinding->setTarget(property);
             QQuickStateAction wa;
             wa.property = property;
@@ -454,8 +454,8 @@ QQuickStateOperation::ActionList QQuickParentChange::actions()
             QQuickStateAction ha(d->target, QLatin1String("height"), height);
             actions << ha;
         } else {
-            QQmlBinding *newBinding = new QQmlBinding(d->heightString.value, d->target, qmlContext(this));
             QQmlProperty property(d->target, QLatin1String("height"));
+            QQmlBinding *newBinding = QQmlBinding::create(&QQmlPropertyPrivate::get(property)->core, d->heightString.value, d->target, qmlContext(this));
             newBinding->setTarget(property);
             QQuickStateAction ha;
             ha.property = property;
@@ -866,31 +866,31 @@ QQuickAnchorChanges::ActionList QQuickAnchorChanges::actions()
     d->baselineProp = QQmlProperty(d->target, QLatin1String("anchors.baseline"));
 
     if (d->anchorSet->d_func()->usedAnchors & QQuickAnchors::LeftAnchor) {
-        d->leftBinding = new QQmlBinding(d->anchorSet->d_func()->leftScript, d->target, qmlContext(this));
+        d->leftBinding = QQmlBinding::create(&QQmlPropertyPrivate::get(d->leftProp)->core, d->anchorSet->d_func()->leftScript, d->target, qmlContext(this));
         d->leftBinding->setTarget(d->leftProp);
     }
     if (d->anchorSet->d_func()->usedAnchors & QQuickAnchors::RightAnchor) {
-        d->rightBinding = new QQmlBinding(d->anchorSet->d_func()->rightScript, d->target, qmlContext(this));
+        d->rightBinding = QQmlBinding::create(&QQmlPropertyPrivate::get(d->rightProp)->core, d->anchorSet->d_func()->rightScript, d->target, qmlContext(this));
         d->rightBinding->setTarget(d->rightProp);
     }
     if (d->anchorSet->d_func()->usedAnchors & QQuickAnchors::HCenterAnchor) {
-        d->hCenterBinding = new QQmlBinding(d->anchorSet->d_func()->hCenterScript, d->target, qmlContext(this));
+        d->hCenterBinding = QQmlBinding::create(&QQmlPropertyPrivate::get(d->hCenterProp)->core, d->anchorSet->d_func()->hCenterScript, d->target, qmlContext(this));
         d->hCenterBinding->setTarget(d->hCenterProp);
     }
     if (d->anchorSet->d_func()->usedAnchors & QQuickAnchors::TopAnchor) {
-        d->topBinding = new QQmlBinding(d->anchorSet->d_func()->topScript, d->target, qmlContext(this));
+        d->topBinding = QQmlBinding::create(&QQmlPropertyPrivate::get(d->topProp)->core, d->anchorSet->d_func()->topScript, d->target, qmlContext(this));
         d->topBinding->setTarget(d->topProp);
     }
     if (d->anchorSet->d_func()->usedAnchors & QQuickAnchors::BottomAnchor) {
-        d->bottomBinding = new QQmlBinding(d->anchorSet->d_func()->bottomScript, d->target, qmlContext(this));
+        d->bottomBinding = QQmlBinding::create(&QQmlPropertyPrivate::get(d->bottomProp)->core, d->anchorSet->d_func()->bottomScript, d->target, qmlContext(this));
         d->bottomBinding->setTarget(d->bottomProp);
     }
     if (d->anchorSet->d_func()->usedAnchors & QQuickAnchors::VCenterAnchor) {
-        d->vCenterBinding = new QQmlBinding(d->anchorSet->d_func()->vCenterScript, d->target, qmlContext(this));
+        d->vCenterBinding = QQmlBinding::create(&QQmlPropertyPrivate::get(d->vCenterProp)->core, d->anchorSet->d_func()->vCenterScript, d->target, qmlContext(this));
         d->vCenterBinding->setTarget(d->vCenterProp);
     }
     if (d->anchorSet->d_func()->usedAnchors & QQuickAnchors::BaselineAnchor) {
-        d->baselineBinding = new QQmlBinding(d->anchorSet->d_func()->baselineScript, d->target, qmlContext(this));
+        d->baselineBinding = QQmlBinding::create(&QQmlPropertyPrivate::get(d->baselineProp)->core, d->anchorSet->d_func()->baselineScript, d->target, qmlContext(this));
         d->baselineBinding->setTarget(d->baselineProp);
     }
 
diff --git a/src/quick/qtquick2.cpp b/src/quick/qtquick2.cpp
index 41e30a1110..bf5b0083e9 100644
--- a/src/quick/qtquick2.cpp
+++ b/src/quick/qtquick2.cpp
@@ -136,9 +136,10 @@ void QQmlQtQuick2DebugStatesDelegate::updateBinding(QQmlContext *context,
 
                 QQmlBinding *newBinding = 0;
                 if (!isLiteralValue) {
-                    newBinding = new QQmlBinding(expression.toString(), object,
-                                                 QQmlContextData::get(context), fileName,
-                                                 line, column);
+                    newBinding = QQmlBinding::create(&QQmlPropertyPrivate::get(property)->core,
+                                                     expression.toString(), object,
+                                                     QQmlContextData::get(context), fileName,
+                                                     line, column);
                     newBinding->setTarget(property);
                 }
 
diff --git a/src/quick/util/qquickpropertychanges.cpp b/src/quick/util/qquickpropertychanges.cpp
index df65e0822b..a42ec31058 100644
--- a/src/quick/util/qquickpropertychanges.cpp
+++ b/src/quick/util/qquickpropertychanges.cpp
@@ -456,11 +456,13 @@ QQuickPropertyChanges::ActionList QQuickPropertyChanges::actions()
             if (e.id != QQmlBinding::Invalid) {
                 QV4::Scope scope(QQmlEnginePrivate::getV4Engine(qmlEngine(this)));
                 QV4::ScopedValue function(scope, QV4::FunctionObject::createQmlFunction(context, object(), d->compilationUnit->runtimeFunctions[e.id]));
-                newBinding = new QQmlBinding(function, object(), context);
+                newBinding = QQmlBinding::create(&QQmlPropertyPrivate::get(prop)->core,
+                                                 function, object(), context);
             }
 //            QQmlBinding *newBinding = e.id != QQmlBinding::Invalid ? QQmlBinding::createBinding(e.id, object(), qmlContext(this)) : 0;
             if (!newBinding)
-                newBinding = new QQmlBinding(e.expression, object(), context, e.url.toString(), e.line, e.column);
+                newBinding = QQmlBinding::create(&QQmlPropertyPrivate::get(prop)->core,
+                                                 e.expression, object(), context, e.url.toString(), e.line, e.column);
 
             if (d->isExplicit) {
                 // in this case, we don't want to assign a binding, per se,
@@ -624,8 +626,11 @@ void QQuickPropertyChanges::changeExpression(const QString &name, const QString
         if (entry.name == name) {
             entry.expression = expression;
             if (state() && state()->isStateActive()) {
-                QQmlBinding *newBinding = new QQmlBinding(expression, object(), qmlContext(this));
-                newBinding->setTarget(d->property(name));
+                auto prop = d->property(name);
+                QQmlBinding *newBinding = QQmlBinding::create(
+                            &QQmlPropertyPrivate::get(prop)->core, expression, object(),
+                            qmlContext(this));
+                newBinding->setTarget(prop);
                 QQmlPropertyPrivate::setBinding(newBinding, QQmlPropertyPrivate::None, QQmlPropertyPrivate::DontRemoveBinding | QQmlPropertyPrivate::BypassInterceptor);
             }
             return;
@@ -643,8 +648,11 @@ void QQuickPropertyChanges::changeExpression(const QString &name, const QString
                 state()->changeBindingInRevertList(object(), name, oldBinding);
             }
 
-            QQmlBinding *newBinding = new QQmlBinding(expression, object(), qmlContext(this));
-            newBinding->setTarget(d->property(name));
+            auto prop = d->property(name);
+            QQmlBinding *newBinding = QQmlBinding::create(
+                        &QQmlPropertyPrivate::get(prop)->core, expression, object(),
+                        qmlContext(this));
+            newBinding->setTarget(prop);
             QQmlPropertyPrivate::setBinding(newBinding, QQmlPropertyPrivate::None, QQmlPropertyPrivate::DontRemoveBinding | QQmlPropertyPrivate::BypassInterceptor);
         } else {
             QQuickStateAction action;
@@ -654,7 +662,9 @@ void QQuickPropertyChanges::changeExpression(const QString &name, const QString
             action.specifiedObject = object();
             action.specifiedProperty = name;
 
-            QQmlBinding *newBinding = new QQmlBinding(expression, object(), qmlContext(this));
+            QQmlBinding *newBinding = QQmlBinding::create(
+                        &QQmlPropertyPrivate::get(action.property)->core, expression,
+                        object(), qmlContext(this));
             if (d->isExplicit) {
                 // don't assign the binding, merely evaluate the expression.
                 // XXX TODO: add a static QQmlJavaScriptExpression::evaluate(QString)
diff --git a/tests/auto/qml/qqmllanguage/testtypes.cpp b/tests/auto/qml/qqmllanguage/testtypes.cpp
index 908600784e..3921f89d23 100644
--- a/tests/auto/qml/qqmllanguage/testtypes.cpp
+++ b/tests/auto/qml/qqmllanguage/testtypes.cpp
@@ -129,9 +129,10 @@ void CustomBinding::componentComplete()
 
         QV4::Scope scope(QQmlEnginePrivate::getV4Engine(qmlEngine(this)));
         QV4::ScopedValue function(scope, QV4::FunctionObject::createQmlFunction(context, m_target, compilationUnit->runtimeFunctions[bindingId]));
-        QQmlBinding *qmlBinding = new QQmlBinding(function, m_target, context);
 
         QQmlProperty property(m_target, name, qmlContext(this));
+        QQmlBinding *qmlBinding = QQmlBinding::create(&QQmlPropertyPrivate::get(property)->core,
+                                                      function, m_target, context);
         qmlBinding->setTarget(property);
         QQmlPropertyPrivate::setBinding(property, qmlBinding);
     }
diff --git a/tests/auto/qml/qqmlproperty/tst_qqmlproperty.cpp b/tests/auto/qml/qqmlproperty/tst_qqmlproperty.cpp
index 5a8f2747a9..7e00147963 100644
--- a/tests/auto/qml/qqmlproperty/tst_qqmlproperty.cpp
+++ b/tests/auto/qml/qqmlproperty/tst_qqmlproperty.cpp
@@ -157,7 +157,7 @@ void tst_qqmlproperty::qmlmetaproperty()
 
     QObject *obj = new QObject;
 
-    QQmlAbstractBinding::Ptr binding(new QQmlBinding(QLatin1String("null"), 0, engine.rootContext()));
+    QQmlAbstractBinding::Ptr binding(QQmlBinding::create(nullptr, QLatin1String("null"), 0, engine.rootContext()));
     QVERIFY(binding);
     QQmlBoundSignalExpression *sigExpr = new QQmlBoundSignalExpression(obj, QObjectPrivate::get(obj)->signalIndex("destroyed()"), QQmlContextData::get(engine.rootContext()), 0, QLatin1String("null"), QString(), -1, -1);
     QQmlJavaScriptExpression::DeleteWatcher sigExprWatcher(sigExpr);
@@ -406,7 +406,7 @@ void tst_qqmlproperty::qmlmetaproperty_object()
     {
         QQmlProperty prop(&object);
 
-        QQmlAbstractBinding::Ptr binding(new QQmlBinding(QLatin1String("null"), 0, engine.rootContext()));
+        QQmlAbstractBinding::Ptr binding(QQmlBinding::create(&QQmlPropertyPrivate::get(prop)->core, QLatin1String("null"), 0, engine.rootContext()));
         QVERIFY(binding);
         QQmlBoundSignalExpression *sigExpr = new QQmlBoundSignalExpression(&object, QObjectPrivate::get(&object)->signalIndex("destroyed()"), QQmlContextData::get(engine.rootContext()), 0, QLatin1String("null"), QString(), -1, -1);
         QQmlJavaScriptExpression::DeleteWatcher sigExprWatcher(sigExpr);
@@ -453,7 +453,7 @@ void tst_qqmlproperty::qmlmetaproperty_object()
     {
         QQmlProperty prop(&dobject);
 
-        QQmlAbstractBinding::Ptr binding(new QQmlBinding(QLatin1String("null"), 0, engine.rootContext()));
+        QQmlAbstractBinding::Ptr binding(QQmlBinding::create(&QQmlPropertyPrivate::get(prop)->core, QLatin1String("null"), 0, engine.rootContext()));
         static_cast<QQmlBinding *>(binding.data())->setTarget(prop);
         QVERIFY(binding);
         QQmlBoundSignalExpression *sigExpr = new QQmlBoundSignalExpression(&dobject, QObjectPrivate::get(&dobject)->signalIndex("clicked()"), QQmlContextData::get(engine.rootContext()), 0, QLatin1String("null"), QString(), -1, -1);
@@ -509,7 +509,7 @@ void tst_qqmlproperty::qmlmetaproperty_object_string()
     {
         QQmlProperty prop(&object, QString("defaultProperty"));
 
-        QQmlAbstractBinding::Ptr binding(new QQmlBinding(QLatin1String("null"), 0, engine.rootContext()));
+        QQmlAbstractBinding::Ptr binding(QQmlBinding::create(&QQmlPropertyPrivate::get(prop)->core, QLatin1String("null"), 0, engine.rootContext()));
         QVERIFY(binding);
         QQmlBoundSignalExpression *sigExpr = new QQmlBoundSignalExpression(&object, QObjectPrivate::get(&object)->signalIndex("destroyed()"), QQmlContextData::get(engine.rootContext()), 0, QLatin1String("null"), QString(), -1, -1);
         QQmlJavaScriptExpression::DeleteWatcher sigExprWatcher(sigExpr);
@@ -556,7 +556,7 @@ void tst_qqmlproperty::qmlmetaproperty_object_string()
     {
         QQmlProperty prop(&dobject, QString("defaultProperty"));
 
-        QQmlAbstractBinding::Ptr binding(new QQmlBinding(QLatin1String("null"), 0, engine.rootContext()));
+        QQmlAbstractBinding::Ptr binding(QQmlBinding::create(&QQmlPropertyPrivate::get(prop)->core, QLatin1String("null"), 0, engine.rootContext()));
         static_cast<QQmlBinding *>(binding.data())->setTarget(prop);
         QVERIFY(binding);
         QQmlBoundSignalExpression *sigExpr = new QQmlBoundSignalExpression(&dobject, QObjectPrivate::get(&dobject)->signalIndex("clicked()"), QQmlContextData::get(engine.rootContext()), 0, QLatin1String("null"), QString(), -1, -1);
@@ -606,7 +606,7 @@ void tst_qqmlproperty::qmlmetaproperty_object_string()
     {
         QQmlProperty prop(&dobject, QString("onClicked"));
 
-        QQmlAbstractBinding::Ptr binding(new QQmlBinding(QLatin1String("null"), 0, engine.rootContext()));
+        QQmlAbstractBinding::Ptr binding(QQmlBinding::create(&QQmlPropertyPrivate::get(prop)->core, QLatin1String("null"), 0, engine.rootContext()));
         static_cast<QQmlBinding *>(binding.data())->setTarget(prop);
         QVERIFY(binding);
         QQmlBoundSignalExpression *sigExpr = new QQmlBoundSignalExpression(&dobject, QQmlPropertyPrivate::get(prop)->signalIndex(), QQmlContextData::get(engine.rootContext()), 0, QLatin1String("null"), QString(), -1, -1);
@@ -655,7 +655,7 @@ void tst_qqmlproperty::qmlmetaproperty_object_string()
     {
         QQmlProperty prop(&dobject, QString("onPropertyWithNotifyChanged"));
 
-        QQmlAbstractBinding::Ptr binding(new QQmlBinding(QLatin1String("null"), 0, engine.rootContext()));
+        QQmlAbstractBinding::Ptr binding(QQmlBinding::create(&QQmlPropertyPrivate::get(prop)->core, QLatin1String("null"), 0, engine.rootContext()));
         static_cast<QQmlBinding *>(binding.data())->setTarget(prop);
         QVERIFY(binding);
         QQmlBoundSignalExpression *sigExpr = new QQmlBoundSignalExpression(&dobject, QQmlPropertyPrivate::get(prop)->signalIndex(), QQmlContextData::get(engine.rootContext()), 0, QLatin1String("null"), QString(), -1, -1);
@@ -710,7 +710,7 @@ void tst_qqmlproperty::qmlmetaproperty_object_context()
     {
         QQmlProperty prop(&object, engine.rootContext());
 
-        QQmlAbstractBinding::Ptr binding(new QQmlBinding(QLatin1String("null"), 0, engine.rootContext()));
+        QQmlAbstractBinding::Ptr binding(QQmlBinding::create(&QQmlPropertyPrivate::get(prop)->core, QLatin1String("null"), 0, engine.rootContext()));
         QVERIFY(binding);
         QQmlBoundSignalExpression *sigExpr = new QQmlBoundSignalExpression(&object, QObjectPrivate::get(&object)->signalIndex("destroyed()"), QQmlContextData::get(engine.rootContext()), 0, QLatin1String("null"), QString(), -1, -1);
         QQmlJavaScriptExpression::DeleteWatcher sigExprWatcher(sigExpr);
@@ -757,7 +757,7 @@ void tst_qqmlproperty::qmlmetaproperty_object_context()
     {
         QQmlProperty prop(&dobject, engine.rootContext());
 
-        QQmlAbstractBinding::Ptr binding(new QQmlBinding(QLatin1String("null"), 0, engine.rootContext()));
+        QQmlAbstractBinding::Ptr binding(QQmlBinding::create(&QQmlPropertyPrivate::get(prop)->core, QLatin1String("null"), 0, engine.rootContext()));
         static_cast<QQmlBinding *>(binding.data())->setTarget(prop);
         QVERIFY(binding);
         QQmlBoundSignalExpression *sigExpr = new QQmlBoundSignalExpression(&dobject, QObjectPrivate::get(&dobject)->signalIndex("clicked()"), QQmlContextData::get(engine.rootContext()), 0, QLatin1String("null"), QString(), -1, -1);
@@ -813,7 +813,7 @@ void tst_qqmlproperty::qmlmetaproperty_object_string_context()
     {
         QQmlProperty prop(&object, QString("defaultProperty"), engine.rootContext());
 
-        QQmlAbstractBinding::Ptr binding(new QQmlBinding(QLatin1String("null"), 0, engine.rootContext()));
+        QQmlAbstractBinding::Ptr binding(QQmlBinding::create(&QQmlPropertyPrivate::get(prop)->core, QLatin1String("null"), 0, engine.rootContext()));
         QVERIFY(binding);
         QQmlBoundSignalExpression *sigExpr = new QQmlBoundSignalExpression(&object, QObjectPrivate::get(&object)->signalIndex("destroyed()"), QQmlContextData::get(engine.rootContext()), 0, QLatin1String("null"), QString(), -1, -1);
         QQmlJavaScriptExpression::DeleteWatcher sigExprWatcher(sigExpr);
@@ -860,7 +860,7 @@ void tst_qqmlproperty::qmlmetaproperty_object_string_context()
     {
         QQmlProperty prop(&dobject, QString("defaultProperty"), engine.rootContext());
 
-        QQmlAbstractBinding::Ptr binding(new QQmlBinding(QLatin1String("null"), 0, engine.rootContext()));
+        QQmlAbstractBinding::Ptr binding(QQmlBinding::create(&QQmlPropertyPrivate::get(prop)->core, QLatin1String("null"), 0, engine.rootContext()));
         static_cast<QQmlBinding *>(binding.data())->setTarget(prop);
         QVERIFY(binding);
         QQmlBoundSignalExpression *sigExpr = new QQmlBoundSignalExpression(&dobject, QObjectPrivate::get(&dobject)->signalIndex("clicked()"), QQmlContextData::get(engine.rootContext()), 0, QLatin1String("null"), QString(), -1, -1);
@@ -910,7 +910,7 @@ void tst_qqmlproperty::qmlmetaproperty_object_string_context()
     {
         QQmlProperty prop(&dobject, QString("onClicked"), engine.rootContext());
 
-        QQmlAbstractBinding::Ptr binding(new QQmlBinding(QLatin1String("null"), 0, engine.rootContext()));
+        QQmlAbstractBinding::Ptr binding(QQmlBinding::create(&QQmlPropertyPrivate::get(prop)->core, QLatin1String("null"), 0, engine.rootContext()));
         static_cast<QQmlBinding *>(binding.data())->setTarget(prop);
         QVERIFY(binding);
         QQmlBoundSignalExpression *sigExpr = new QQmlBoundSignalExpression(&dobject, QQmlPropertyPrivate::get(prop)->signalIndex(), QQmlContextData::get(engine.rootContext()), 0, QLatin1String("null"), QString(), -1, -1);
@@ -959,7 +959,7 @@ void tst_qqmlproperty::qmlmetaproperty_object_string_context()
     {
         QQmlProperty prop(&dobject, QString("onPropertyWithNotifyChanged"), engine.rootContext());
 
-        QQmlAbstractBinding::Ptr binding(new QQmlBinding(QLatin1String("null"), 0, engine.rootContext()));
+        QQmlAbstractBinding::Ptr binding(QQmlBinding::create(&QQmlPropertyPrivate::get(prop)->core, QLatin1String("null"), 0, engine.rootContext()));
         static_cast<QQmlBinding *>(binding.data())->setTarget(prop);
         QVERIFY(binding);
         QQmlBoundSignalExpression *sigExpr = new QQmlBoundSignalExpression(&dobject, QQmlPropertyPrivate::get(prop)->signalIndex(), QQmlContextData::get(engine.rootContext()), 0, QLatin1String("null"), QString(), -1, -1);