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diff --git a/src/corelib/thread/qlocking_p.h b/src/corelib/thread/qlocking_p.h
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+/****************************************************************************
+**
+** Copyright (C) 2019 Klarälvdalens Datakonsult AB, a KDAB Group company, info@kdab.com, author Marc Mutz <marc.mutz@kdab.com>
+** 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 QLOCKING_P_H
+#define QLOCKING_P_H
+
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt API.  It exists for the convenience
+// of qmutex.cpp, qmutex_unix.cpp, and qmutex_win.cpp.  This header
+// file may change from version to version without notice, or even be
+// removed.
+//
+// We mean it.
+//
+
+#include <QtCore/qmutex.h>
+
+#include <mutex>
+
+QT_BEGIN_NAMESPACE
+
+//
+// This API is bridging the time until we can depend on C++17:
+//
+// - qt_scoped_lock returns a lock that cannot be unlocked again before the end of the scope
+// - qt_unique_lock returns a lock that can be unlock()ed and moved around
+// - for compat with QMutexLocker, qt_unique_lock supports passing by pointer.
+//   Do NOT use this overload lightly; it's only for cases such as where a Q_GLOBAL_STATIC
+//   may have already been deleted. In particular, do NOT port from
+//       QMutexLocker locker(&mutex);
+//   to
+//       auto locker = qt_unique_lock(&mutex);
+//   as this will not port automatically to std::unique_lock come C++17!
+//
+// The intent, come C++17, is to replace
+//     qt_scoped_lock(mutex);
+//     qt_unique_lock(mutex); // except qt_unique_lock(&mutex)
+// with
+//     std::scoped_lock(mutex);
+//     std::unique_lock(mutex);
+// resp. (C++17 meaning CTAD, guaranteed copy elision + scoped_lock available on all platforms),
+// so please use these functions only in ways which don't break this mechanical search & replace.
+//
+
+namespace {
+
+template <typename Mutex, typename Lock =
+#if defined(__cpp_guaranteed_copy_elision) && __cpp_guaranteed_copy_elision >= 201606L
+# if defined(__cpp_lib_scoped_lock) && __cpp_lib_scoped_lock >= 201703L
+          std::scoped_lock
+# else
+          std::lock_guard
+# endif
+#else
+          std::unique_lock
+#endif
+          <typename std::decay<Mutex>::type>
+>
+Lock qt_scoped_lock(Mutex &mutex)
+{
+    return Lock(mutex);
+}
+
+template <typename Mutex, typename Lock = std::unique_lock<typename std::decay<Mutex>::type>>
+Lock qt_unique_lock(Mutex &mutex)
+{
+    return Lock(mutex);
+}
+
+template <typename Mutex, typename Lock = std::unique_lock<typename std::decay<Mutex>::type>>
+Lock qt_unique_lock(Mutex *mutex)
+{
+    return mutex ? Lock(*mutex) : Lock() ;
+}
+
+} // unnamed namespace
+
+QT_END_NAMESPACE
+
+#endif // QLOCKING_P_H