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diff --git a/src/qml/qmltc/qqmltcobjectcreationhelper_p.h b/src/qml/qmltc/qqmltcobjectcreationhelper_p.h
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+++ b/src/qml/qmltc/qqmltcobjectcreationhelper_p.h
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+// Copyright (C) 2021 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
+
+#ifndef QQMLTCOBJECTCREATIONHELPER_P_H
+#define QQMLTCOBJECTCREATIONHELPER_P_H
+
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt API.  It exists purely as an
+// implementation detail.  This header file may change from version to
+// version without notice, or even be removed.
+//
+// We mean it.
+//
+
+#include <QtQml/qqml.h>
+#include <QtCore/private/qglobal_p.h>
+#include <QtCore/qversionnumber.h>
+#include <private/qtqmlglobal_p.h>
+#include <private/qqmltype_p.h>
+
+#include <array>
+
+QT_BEGIN_NAMESPACE
+
+/*!
+    \internal
+
+    (Kind of) type-erased  object creation utility that can be used throughout
+    the generated C++ code. By nature it shows relative data to the current QML
+    document and allows to get and set object pointers.
+ */
+class QQmltcObjectCreationHelper
+{
+    QObject **m_data = nullptr; // QObject* array
+    const qsizetype m_size = 0; // size of m_data array, exists for bounds checking
+    const qsizetype m_offset = 0; // global offset into m_data array
+
+    qsizetype offset() const { return m_offset; }
+
+public:
+    /*!
+        Constructs initial "view" from basic data. Supposed to only be called
+        once from QQmltcObjectCreationBase.
+    */
+    QQmltcObjectCreationHelper(QObject **data, qsizetype size) : m_data(data), m_size(size)
+    {
+        Q_UNUSED(m_size);
+    }
+
+    /*!
+        Constructs new "view" from \a base view, adding \a localOffset to the
+        offset of that base.
+    */
+    QQmltcObjectCreationHelper(const QQmltcObjectCreationHelper *base, qsizetype localOffset)
+        : m_data(base->m_data), m_size(base->m_size), m_offset(base->m_offset + localOffset)
+    {
+    }
+
+    template<typename T>
+    T *get(qsizetype i) const
+    {
+        Q_ASSERT(m_data);
+        Q_ASSERT(i >= 0 && i + offset() < m_size);
+        Q_ASSERT(qobject_cast<T *>(m_data[i + offset()]) != nullptr);
+        // Note: perform cheap cast as we know *exactly* the real type of the
+        // object
+        return static_cast<T *>(m_data[i + offset()]);
+    }
+
+    void set(qsizetype i, QObject *object)
+    {
+        Q_ASSERT(m_data);
+        Q_ASSERT(i >= 0 && i + offset() < m_size);
+        Q_ASSERT(m_data[i + offset()] == nullptr); // prevent accidental resets
+        m_data[i + offset()] = object;
+    }
+
+    template<typename T>
+    static constexpr uint typeCount() noexcept
+    {
+        return T::q_qmltc_typeCount();
+    }
+};
+
+/*!
+    \internal
+
+    Base helper for qmltc-generated types that linearly stores pointers to all
+    the to-be-created objects for fast access during object creation.
+ */
+template<typename QmltcGeneratedType>
+class QQmltcObjectCreationBase
+{
+    // Note: +1 for the document root itself
+    std::array<QObject *, QmltcGeneratedType::q_qmltc_typeCount() + 1> m_objects = {};
+
+public:
+    QQmltcObjectCreationHelper view()
+    {
+        return QQmltcObjectCreationHelper(m_objects.data(), m_objects.size());
+    }
+};
+
+struct QmltcTypeData
+{
+    QQmlType::RegistrationType regType = QQmlType::CppType;
+    int allocationSize = 0;
+    const QMetaObject *metaObject = nullptr;
+
+    template<typename QmltcGeneratedType>
+    QmltcTypeData(QmltcGeneratedType *)
+        : allocationSize(sizeof(QmltcGeneratedType)),
+          metaObject(&QmltcGeneratedType::staticMetaObject)
+    {
+    }
+};
+
+Q_QML_EXPORT void qmltcCreateDynamicMetaObject(QObject *object, const QmltcTypeData &data);
+
+QT_END_NAMESPACE
+
+#endif // QQMLTCOBJECTCREATIONHELPER_P_H