1 files changed, 12 insertions, 3 deletions
diff --git a/src/qml/qml/qqmlpropertybinding.cpp b/src/qml/qml/qqmlpropertybinding.cpp
index 5c8325a425..c8a7e6256a 100644
--- a/src/qml/qml/qqmlpropertybinding.cpp
+++ b/src/qml/qml/qqmlpropertybinding.cpp
@@ -16,6 +16,8 @@
 
 QT_BEGIN_NAMESPACE
 
+using namespace Qt::Literals::StringLiterals;
+
 Q_LOGGING_CATEGORY(lcQQPropertyBinding, "qt.qml.propertybinding");
 
 QUntypedPropertyBinding QQmlPropertyBinding::create(const QQmlPropertyData *pd, QV4::Function *function,
@@ -230,10 +232,17 @@ void QQmlPropertyBinding::handleUndefinedAssignment(QQmlEnginePrivate *ep, void
         setIsUndefined(true);
         //suspend binding evaluation state for reset and subsequent read
         auto state = QtPrivate::suspendCurrentBindingStatus();
-        prop.reset();
+        prop.reset(); // May re-allocate the bindingData
         QVariant currentValue = QVariant(prop.propertyMetaType(), propertyDataPtr);
         QtPrivate::restoreBindingStatus(state);
         writeBackCurrentValue(std::move(currentValue));
+
+        // Re-fetch binding data
+        bindingData = storage->bindingData(propertyDataPtr);
+        if (!bindingData)
+            bindingData = bindingDataFromPropertyData(propertyDataPtr, propertyData->propType());
+        bindingDataPointer = QPropertyBindingDataPointer {bindingData};
+
         // reattach the binding (without causing a new notification)
         if (Q_UNLIKELY(bindingData->d() & QtPrivate::QPropertyBindingData::BindingBit)) {
             qCWarning(lcQQPropertyBinding) << "Resetting " << prop.name() << "due to the binding becoming undefined  caused a new binding to be installed\n"
@@ -245,7 +254,7 @@ void QQmlPropertyBinding::handleUndefinedAssignment(QQmlEnginePrivate *ep, void
         firstObserver = bindingDataPointer.firstObserver();
         bindingData->d_ref() = reinterpret_cast<quintptr>(this) | QtPrivate::QPropertyBindingData::BindingBit;
         if (firstObserver)
-            bindingDataPointer.setObservers(firstObserver.ptr);
+            prependObserver(firstObserver);
     } else {
         QQmlError qmlError;
         auto location = jsExpression()->sourceLocation();
@@ -272,7 +281,7 @@ QString QQmlPropertyBinding::createBindingLoopErrorDescription()
     Q_ASSERT(propertyData);
     Q_ASSERT(!targetIndex().hasValueTypeIndex());
     QQmlProperty prop = QQmlPropertyPrivate::restore(target(), *propertyData, &valueTypeData, nullptr);
-    return QStringLiteral(R"(QML %1: Binding loop detected for property "%2")").arg(QQmlMetaType::prettyTypeName(target()) , prop.name());
+    return R"(QML %1: Binding loop detected for property "%2")"_L1.arg(QQmlMetaType::prettyTypeName(target()) , prop.name());
 }
 
 void QQmlPropertyBinding::bindingErrorCallback(QPropertyBindingPrivate *that)