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Diffstat (limited to 'src/corelib/global/qvolatile_p.h')
-rw-r--r-- | src/corelib/global/qvolatile_p.h | 53 |
1 files changed, 53 insertions, 0 deletions
diff --git a/src/corelib/global/qvolatile_p.h b/src/corelib/global/qvolatile_p.h new file mode 100644 index 0000000000..36787ecd87 --- /dev/null +++ b/src/corelib/global/qvolatile_p.h @@ -0,0 +1,53 @@ +// Copyright (C) 2021 Klarälvdalens Datakonsult AB, a KDAB Group company, info@kdab.com, author Marc Mutz <marc.mutz@kdab.com> +// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only + +#ifndef QVOLATILE_P_H +#define QVOLATILE_P_H + +// +// W A R N I N G +// ------------- +// +// This file is not part of the Qt API. It exists for the convenience +// of a number of Qt sources files. This header file may change from +// version to version without notice, or even be removed. +// +// We mean it. +// + +#include <QtCore/private/qglobal_p.h> + +QT_BEGIN_NAMESPACE + +namespace QtPrivate { +template <typename T> +using if_volatile = std::enable_if_t<std::is_volatile_v<T>, bool>; + +// +// C++20-deprecated volatile compound operations, rewritten as separated operations +// + +// these functions return `auto`, not `T`, to strip cv-qualifiers without having +// to mention the `volatile` keyword + +template <typename T, QtPrivate::if_volatile<T> = true> +auto volatilePreIncrement(T &x) { + auto y = x; + ++y; + x = y; + return y; +} + +template <typename T, QtPrivate::if_volatile<T> = true> +auto volatilePreDecrement(T &x) +{ + auto y = x; + --y; + x = y; + return y; +} +} // namespace QtPrivate + +QT_END_NAMESPACE + +#endif // QVOLATILE_H |