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diff --git a/src/corelib/thread/qpromise.h b/src/corelib/thread/qpromise.h
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+/****************************************************************************
+**
+** Copyright (C) 2020 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtCore module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QPROMISE_H
+#define QPROMISE_H
+
+#include <QtCore/qglobal.h>
+#include <QtCore/qfuture.h>
+
+QT_REQUIRE_CONFIG(future);
+
+QT_BEGIN_NAMESPACE
+
+template<typename T>
+class QPromise
+{
+    static_assert (std::is_copy_constructible_v<T>
+                   || std::is_move_constructible_v<T>
+                   || std::is_same_v<T, void>,
+                   "Type with copy or move constructors or type void is required");
+public:
+    QPromise() = default;
+    Q_DISABLE_COPY(QPromise)
+    QPromise(QPromise<T> &&other) : d(other.d)
+    {
+        // In constructor, there's no need to perform swap(). Assign new
+        // QFutureInterface to other.d instead which is slightly cheaper.
+        other.d = QFutureInterface<T>();
+    }
+    QPromise& operator=(QPromise<T> &&other)
+    {
+        swap(other);
+        return *this;
+    }
+    ~QPromise()
+    {
+        const int state = d.loadState();
+        // If QFutureInterface has no state, there is nothing to be done
+        if (state == static_cast<int>(QFutureInterfaceBase::State::NoState))
+            return;
+        // Otherwise, if computation is not finished at this point, cancel
+        // potential waits
+        if (!(state & QFutureInterfaceBase::State::Finished)) {
+            d.cancel();
+            reportFinished();  // required to finalize the state
+        }
+    }
+
+    // Core QPromise APIs
+    QFuture<T> future() const { return d.future(); }
+    template<typename U = T,
+             typename = QtPrivate::EnableForNonVoid<std::decay_t<U>>,
+             typename = QtPrivate::EnableIfSameOrConvertible<std::decay_t<U>, std::decay_t<T>>>
+    void addResult(U &&result, int index = -1)
+    {
+        d.reportResult(std::forward<U>(result), index);
+    }
+#ifndef QT_NO_EXCEPTIONS
+    void setException(const QException &e) { d.reportException(e); }
+    void setException(std::exception_ptr e) { d.reportException(e); }
+#endif
+    void reportStarted() { d.reportStarted(); }
+    void reportFinished() { d.reportFinished(); }
+
+    void suspendIfRequested() { d.suspendIfRequested(); }
+
+    bool isCanceled() const { return d.isCanceled(); }
+
+    // Progress methods
+    void setProgressRange(int minimum, int maximum) { d.setProgressRange(minimum, maximum); }
+    void setProgressValue(int progressValue) { d.setProgressValue(progressValue); }
+    void setProgressValueAndText(int progressValue, const QString &progressText)
+    {
+        d.setProgressValueAndText(progressValue, progressText);
+    }
+
+private:
+    mutable QFutureInterface<T> d = QFutureInterface<T>();
+
+    void swap(QPromise<T> &other)
+    {
+        // Note: copy operations are expensive! They trigger several atomic
+        //       reference counts
+        auto tmp = this->d;
+        this->d = other.d;
+        other.d = tmp;
+    }
+};
+
+QT_END_NAMESPACE
+
+#endif  // QPROMISE_H