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diff --git a/src/corelib/global/qrandom.h b/src/corelib/global/qrandom.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 QRANDOM_H
+#define QRANDOM_H
+
+#include <QtCore/qglobal.h>
+#include <algorithm>    // for std::generate
+#include <random>       // for std::mt19937
+
+QT_BEGIN_NAMESPACE
+
+class QRandomGenerator
+{
+    // restrict the template parameters to unsigned integers 32 bits wide or larger
+    template <typename UInt> using IfValidUInt =
+        typename std::enable_if<std::is_unsigned<UInt>::value && sizeof(UInt) >= sizeof(uint), bool>::type;
+public:
+    QRandomGenerator(quint32 seedValue = 1)
+        : QRandomGenerator(&seedValue, 1)
+    {}
+    template <qssize_t N> QRandomGenerator(const quint32 (&seedBuffer)[N])
+        : QRandomGenerator(seedBuffer, seedBuffer + N)
+    {}
+    QRandomGenerator(const quint32 *seedBuffer, qssize_t len)
+        : QRandomGenerator(seedBuffer, seedBuffer + len)
+    {}
+    Q_CORE_EXPORT QRandomGenerator(std::seed_seq &sseq) Q_DECL_NOTHROW;
+    Q_CORE_EXPORT QRandomGenerator(const quint32 *begin, const quint32 *end);
+
+    // copy constructor & assignment operator (move unnecessary)
+    Q_CORE_EXPORT QRandomGenerator(const QRandomGenerator &other);
+    Q_CORE_EXPORT QRandomGenerator &operator=(const QRandomGenerator &other);
+
+    friend Q_CORE_EXPORT bool operator==(const QRandomGenerator &rng1, const QRandomGenerator &rng2);
+    friend bool operator!=(const QRandomGenerator &rng1, const QRandomGenerator &rng2)
+    {
+        return !(rng1 == rng2);
+    }
+
+    quint32 generate()
+    {
+        quint32 ret;
+        fillRange(&ret, 1);
+        return ret;
+    }
+
+    quint64 generate64()
+    {
+        quint32 buf[2];
+        fillRange(buf);
+        return buf[0] | (quint64(buf[1]) << 32);
+    }
+
+    double generateDouble()
+    {
+        // IEEE 754 double precision has:
+        //   1 bit      sign
+        //  10 bits     exponent
+        //  53 bits     mantissa
+        // In order for our result to be normalized in the range [0, 1), we
+        // need exactly 53 bits of random data. Use generate64() to get enough.
+        quint64 x = generate64();
+        quint64 limit = Q_UINT64_C(1) << std::numeric_limits<double>::digits;
+        x >>= std::numeric_limits<quint64>::digits - std::numeric_limits<double>::digits;
+        return double(x) / double(limit);
+    }
+
+    double bounded(double highest)
+    {
+        return generateDouble() * highest;
+    }
+
+    quint32 bounded(quint32 highest)
+    {
+        quint64 value = generate();
+        value *= highest;
+        value /= (max)() + quint64(1);
+        return quint32(value);
+    }
+
+    int bounded(int highest)
+    {
+        return int(bounded(quint32(highest)));
+    }
+
+    quint32 bounded(quint32 lowest, quint32 highest)
+    {
+        return bounded(highest - lowest) + lowest;
+    }
+
+    int bounded(int lowest, int highest)
+    {
+        return bounded(highest - lowest) + lowest;
+    }
+
+    template <typename UInt, IfValidUInt<UInt> = true>
+    void fillRange(UInt *buffer, qssize_t count)
+    {
+        _fillRange(buffer, buffer + count);
+    }
+
+    template <typename UInt, size_t N, IfValidUInt<UInt> = true>
+    void fillRange(UInt (&buffer)[N])
+    {
+        _fillRange(buffer, buffer + N);
+    }
+
+    // API like std::seed_seq
+    template <typename ForwardIterator>
+    void generate(ForwardIterator begin, ForwardIterator end)
+    {
+        std::generate(begin, end, [this]() { return generate(); });
+    }
+
+    void generate(quint32 *begin, quint32 *end)
+    {
+        _fillRange(begin, end);
+    }
+
+    // API like std:: random engines
+    typedef quint32 result_type;
+    result_type operator()() { return generate(); }
+    void seed(quint32 s = 1) { *this = { s }; }
+    void seed(std::seed_seq &sseq) Q_DECL_NOTHROW { *this = { sseq }; }
+    Q_CORE_EXPORT void discard(unsigned long long z);
+    static Q_DECL_CONSTEXPR result_type min() { return (std::numeric_limits<result_type>::min)(); }
+    static Q_DECL_CONSTEXPR result_type max() { return (std::numeric_limits<result_type>::max)(); }
+
+    static inline Q_DECL_CONST_FUNCTION QRandomGenerator *system();
+    static inline Q_DECL_CONST_FUNCTION QRandomGenerator *global();
+    static inline QRandomGenerator securelySeeded();
+
+protected:
+    enum System {};
+    QRandomGenerator(System);
+
+private:
+    Q_CORE_EXPORT void _fillRange(void *buffer, void *bufferEnd);
+
+    friend class QRandomGenerator64;
+    struct SystemGenerator;
+    struct SystemAndGlobalGenerators;
+    typedef std::mt19937 RandomEngine;
+
+    union Storage {
+        uint dummy;
+#ifdef Q_COMPILER_UNRESTRICTED_UNIONS
+        RandomEngine twister;
+        RandomEngine &engine() { return twister; }
+        const RandomEngine &engine() const { return twister; }
+#else
+        std::aligned_storage<sizeof(RandomEngine), Q_ALIGNOF(RandomEngine)>::type buffer;
+        RandomEngine &engine() { return reinterpret_cast<RandomEngine &>(buffer); }
+        const RandomEngine &engine() const { return reinterpret_cast<const RandomEngine &>(buffer); }
+#endif
+
+        Q_STATIC_ASSERT_X(std::is_trivially_destructible<RandomEngine>::value,
+                          "std::mersenne_twister not trivially destructible as expected");
+        Q_DECL_CONSTEXPR Storage();
+    };
+    uint type;
+    Storage storage;
+};
+
+class QRandomGenerator64 : public QRandomGenerator
+{
+    QRandomGenerator64(System);
+public:
+    // unshadow generate() overloads, since we'll override.
+    using QRandomGenerator::generate;
+    quint64 generate() { return generate64(); }
+
+    typedef quint64 result_type;
+    result_type operator()() { return generate64(); }
+
+#ifndef Q_QDOC
+    QRandomGenerator64(quint32 seedValue = 1)
+        : QRandomGenerator(seedValue)
+    {}
+    template <qssize_t N> QRandomGenerator64(const quint32 (&seedBuffer)[N])
+        : QRandomGenerator(seedBuffer)
+    {}
+    QRandomGenerator64(const quint32 *seedBuffer, qssize_t len)
+        : QRandomGenerator(seedBuffer, len)
+    {}
+    QRandomGenerator64(std::seed_seq &sseq) Q_DECL_NOTHROW
+        : QRandomGenerator(sseq)
+    {}
+    QRandomGenerator64(const quint32 *begin, const quint32 *end)
+        : QRandomGenerator(begin, end)
+    {}
+    QRandomGenerator64(const QRandomGenerator &other) : QRandomGenerator(other) {}
+
+    void discard(unsigned long long z)
+    {
+        Q_ASSERT_X(z * 2 > z, "QRandomGenerator64::discard",
+                   "Overflow. Are you sure you want to skip over 9 quintillion samples?");
+        QRandomGenerator::discard(z * 2);
+    }
+
+    static Q_DECL_CONSTEXPR result_type min() { return (std::numeric_limits<result_type>::min)(); }
+    static Q_DECL_CONSTEXPR result_type max() { return (std::numeric_limits<result_type>::max)(); }
+    static Q_DECL_CONST_FUNCTION Q_CORE_EXPORT QRandomGenerator64 *system();
+    static Q_DECL_CONST_FUNCTION Q_CORE_EXPORT QRandomGenerator64 *global();
+    static Q_CORE_EXPORT QRandomGenerator64 securelySeeded();
+#endif // Q_QDOC
+};
+
+inline QRandomGenerator *QRandomGenerator::system()
+{
+    return QRandomGenerator64::system();
+}
+
+inline QRandomGenerator *QRandomGenerator::global()
+{
+    return QRandomGenerator64::global();
+}
+
+QRandomGenerator QRandomGenerator::securelySeeded()
+{
+    return QRandomGenerator64::securelySeeded();
+}
+
+QT_END_NAMESPACE
+
+#endif // QRANDOM_H