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diff --git a/src/qml/common/qjsnumbercoercion.h b/src/qml/common/qjsnumbercoercion.h
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+/****************************************************************************
+**
+** Copyright (C) 2020 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtQml 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 QJSNUMBERCOERCION_H
+#define QJSNUMBERCOERCION_H
+
+#include <QtCore/qglobal.h>
+#include <cstring>
+
+QT_BEGIN_NAMESPACE
+
+class QJSNumberCoercion
+{
+public:
+    static constexpr int toInteger(double d) {
+        int i = static_cast<int>(d);
+        if (equals(i, d))
+            return i;
+        return QJSNumberCoercion(d).toInteger();
+    }
+
+    static constexpr bool equals(double lhs, double rhs)
+    {
+        QT_WARNING_PUSH
+        QT_WARNING_DISABLE_FLOAT_COMPARE
+        return lhs == rhs;
+        QT_WARNING_POP
+    }
+
+private:
+    constexpr QJSNumberCoercion(double dbl)
+    {
+        // the dbl == 0 path is guaranteed constexpr. The other one may or may not be, depending
+        // on whether and how the compiler inlines the memcpy.
+        // In order to declare the ctor constexpr we need one guaranteed constexpr path.
+        if (!equals(dbl, 0))
+            memcpy(&d, &dbl, sizeof(double));
+    }
+
+    constexpr int sign() const
+    {
+        return (d >> 63) ? -1 : 1;
+    }
+
+    constexpr bool isDenormal() const
+    {
+        return static_cast<int>((d << 1) >> 53) == 0;
+    }
+
+    constexpr int exponent() const
+    {
+        return static_cast<int>((d << 1) >> 53) - 1023;
+    }
+
+    constexpr quint64 significant() const
+    {
+        quint64 m = (d << 12) >> 12;
+        if (!isDenormal())
+            m |= (static_cast<quint64>(1) << 52);
+        return m;
+    }
+
+    constexpr int toInteger()
+    {
+        int e = exponent() - 52;
+        if (e < 0) {
+            if (e <= -53)
+                return 0;
+            return sign() * static_cast<int>(significant() >> -e);
+        } else {
+            if (e > 31)
+                return 0;
+            return sign() * (static_cast<int>(significant()) << e);
+        }
+    }
+
+    quint64 d = 0;
+};
+
+QT_END_NAMESPACE
+
+#endif // QJSNUMBERCOERCION_H