diff options
Diffstat (limited to 'src/corelib/global/qglobalstatic.h')
| -rw-r--r-- | src/corelib/global/qglobalstatic.h | 74 |
1 files changed, 25 insertions, 49 deletions
diff --git a/src/corelib/global/qglobalstatic.h b/src/corelib/global/qglobalstatic.h index 1e35cb29f0..93127adab3 100644 --- a/src/corelib/global/qglobalstatic.h +++ b/src/corelib/global/qglobalstatic.h @@ -1,48 +1,12 @@ -/**************************************************************************** -** -** Copyright (C) 2021 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. -** -** $QT_END_LICENSE$ -** -****************************************************************************/ - -#include <QtCore/qglobal.h> +// Copyright (C) 2021 Intel Corporation. +// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only #ifndef QGLOBALSTATIC_H #define QGLOBALSTATIC_H +#include <QtCore/qassert.h> #include <QtCore/qatomic.h> +#include <QtCore/qtclasshelpermacros.h> #include <atomic> // for bootstrapped (no thread) builds #include <type_traits> @@ -63,7 +27,7 @@ template <typename QGS> union Holder using PlainType = std::remove_cv_t<Type>; static constexpr bool ConstructionIsNoexcept = noexcept(QGS::innerFunction(nullptr)); - static inline QBasicAtomicInteger<qint8> guard = { QtGlobalStatic::Uninitialized }; + Q_CONSTINIT static inline QBasicAtomicInteger<qint8> guard = { QtGlobalStatic::Uninitialized }; // union's sole member PlainType storage; @@ -76,9 +40,18 @@ template <typename QGS> union Holder ~Holder() { + // TSAN does not support atomic_thread_fence and GCC complains: + // https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97868 + // https://github.com/google/sanitizers/issues/1352 +QT_WARNING_PUSH +#if defined(Q_CC_GNU_ONLY) && Q_CC_GNU >= 1100 +QT_WARNING_DISABLE_GCC("-Wtsan") +#endif + // import changes to *pointer() by other threads before running ~PlainType(): + std::atomic_thread_fence(std::memory_order_acquire); +QT_WARNING_POP pointer()->~PlainType(); - std::atomic_thread_fence(std::memory_order_acquire); // avoid mixing stores to guard and *pointer() - guard.storeRelaxed(QtGlobalStatic::Destroyed); + guard.storeRelease(QtGlobalStatic::Destroyed); } PlainType *pointer() noexcept @@ -94,8 +67,8 @@ template <typename Holder> struct QGlobalStatic { using Type = typename Holder::Type; - bool isDestroyed() const { return guardValue() <= QtGlobalStatic::Destroyed; } - bool exists() const { return guardValue() == QtGlobalStatic::Initialized; } + bool isDestroyed() const noexcept { return guardValue() <= QtGlobalStatic::Destroyed; } + bool exists() const noexcept { return guardValue() == QtGlobalStatic::Initialized; } operator Type *() { if (isDestroyed()) @@ -110,13 +83,13 @@ template <typename Holder> struct QGlobalStatic } Type *operator->() { - Q_ASSERT_X(!isDestroyed(), "Q_GLOBAL_STATIC", + Q_ASSERT_X(!isDestroyed(), Q_FUNC_INFO, "The global static was used after being destroyed"); return instance(); } Type &operator*() { - Q_ASSERT_X(!isDestroyed(), "Q_GLOBAL_STATIC", + Q_ASSERT_X(!isDestroyed(), Q_FUNC_INFO, "The global static was used after being destroyed"); return *instance(); } @@ -127,13 +100,15 @@ protected: static Holder holder; return holder.pointer(); } - static QtGlobalStatic::GuardValues guardValue() + static QtGlobalStatic::GuardValues guardValue() noexcept { return QtGlobalStatic::GuardValues(Holder::guard.loadAcquire()); } }; #define Q_GLOBAL_STATIC_WITH_ARGS(TYPE, NAME, ARGS) \ + QT_WARNING_PUSH \ + QT_WARNING_DISABLE_CLANG("-Wunevaluated-expression") \ namespace { struct Q_QGS_ ## NAME { \ typedef TYPE QGS_Type; \ static void innerFunction(void *pointer) \ @@ -142,7 +117,8 @@ protected: new (pointer) QGS_Type ARGS; \ } \ }; } \ - static QGlobalStatic<QtGlobalStatic::Holder<Q_QGS_ ## NAME>> NAME; \ + Q_CONSTINIT static QGlobalStatic<QtGlobalStatic::Holder<Q_QGS_ ## NAME>> NAME; \ + QT_WARNING_POP /**/ #define Q_GLOBAL_STATIC(TYPE, NAME, ...) \ |