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diff --git a/src/corelib/thread/qfutex_p.h b/src/corelib/thread/qfutex_p.h
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+/****************************************************************************
+**
+** Copyright (C) 2017 Intel Corporation.
+** 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 QFUTEX_P_H
+#define QFUTEX_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 <qglobal.h>
+
+QT_BEGIN_NAMESPACE
+
+namespace QtDummyFutex {
+    Q_DECL_CONSTEXPR inline bool futexAvailable() { return false; }
+    template <typename Atomic>
+    inline bool futexWait(Atomic &, typename Atomic::Type, int = 0)
+    { Q_UNREACHABLE(); return false; }
+    template <typename Atomic> inline void futexWakeOne(Atomic &)
+    { Q_UNREACHABLE(); }
+    template <typename Atomic> inline void futexWakeAll(Atomic &)
+    { Q_UNREACHABLE(); }
+}
+
+QT_END_NAMESPACE
+
+#if defined(Q_OS_LINUX) && !defined(QT_LINUXBASE)
+// use Linux mutexes everywhere except for LSB builds
+#  include <sys/syscall.h>
+#  include <errno.h>
+#  include <limits.h>
+#  include <unistd.h>
+#  include <asm/unistd.h>
+#  include <linux/futex.h>
+#  define QT_ALWAYS_USE_FUTEX
+
+// if not defined in linux/futex.h
+#  define FUTEX_PRIVATE_FLAG        128         // added in v2.6.22
+
+QT_BEGIN_NAMESPACE
+namespace QtLinuxFutex {
+    constexpr inline bool futexAvailable() { return true; }
+    inline int _q_futex(int *addr, int op, int val, quintptr val2 = 0,
+                        int *addr2 = nullptr, int val3 = 0) Q_DECL_NOTHROW
+    {
+        // we use __NR_futex because some libcs (like Android's bionic) don't
+        // provide SYS_futex etc.
+        return syscall(__NR_futex, addr, op | FUTEX_PRIVATE_FLAG, val, val2, addr2, val3);
+    }
+    template <typename T> int *addr(T *ptr)
+    {
+        int *int_addr = reinterpret_cast<int *>(ptr);
+#if Q_BYTE_ORDER == Q_BIG_ENDIAN
+        if (sizeof(T) > sizeof(int))
+            int_addr++; //We want a pointer to the least significant half
+#endif
+        return int_addr;
+    }
+
+    template <typename Atomic>
+    inline void futexWait(Atomic &futex, typename Atomic::Type expectedValue)
+    {
+        _q_futex(addr(&futex), FUTEX_WAIT, qintptr(expectedValue));
+    }
+    template <typename Atomic>
+    inline bool futexWait(Atomic &futex, typename Atomic::Type expectedValue, qint64 nstimeout)
+    {
+        struct timespec ts;
+        ts.tv_sec = nstimeout / 1000 / 1000 / 1000;
+        ts.tv_nsec = nstimeout % (1000 * 1000 * 1000);
+        int r = _q_futex(addr(&futex), FUTEX_WAIT, qintptr(expectedValue), quintptr(&ts));
+        return r == 0 || errno != ETIMEDOUT;
+    }
+    template <typename Atomic> inline void futexWakeOne(Atomic &futex)
+    {
+        _q_futex(addr(&futex), FUTEX_WAKE, 1);
+    }
+    template <typename Atomic> inline void futexWakeAll(Atomic &futex)
+    {
+        _q_futex(addr(&futex), FUTEX_WAKE, INT_MAX);
+    }
+    template <typename Atomic> inline
+    void futexWakeOp(Atomic &futex1, int wake1, int wake2, Atomic &futex2, quint32 op)
+    {
+        _q_futex(addr(&futex1), FUTEX_WAKE_OP, wake1, wake2, addr(&futex2), op);
+    }
+}
+namespace QtFutex = QtLinuxFutex;
+QT_END_NAMESPACE
+
+#else
+
+QT_BEGIN_NAMESPACE
+namespace QtFutex = QtDummyFutex;
+QT_END_NAMESPACE
+#endif
+
+#endif // QFUTEX_P_H