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| author | Fabian Kosmale <fabian.kosmale@qt.io> | 2021-03-20 18:35:59 +0100 |
|---|---|---|
| committer | Fabian Kosmale <fabian.kosmale@qt.io> | 2021-03-21 09:13:00 +0100 |
| commit | b8b50c6c7a6df17db03ff6fd3a2501511e51703f (patch) | |
| tree | c2e432b305f6f94ae79abce9f48997aea7f37935 /src/corelib/global/qglobalstatic.h | |
| parent | 52e0a91fbc187ca09d3ea6279e8bdce982edc586 (diff) | |
Clenaup Q_COMPILER_THREADSAFE_STATICS
Change-Id: I1cf0646d4e6c9b30a7ef6538d81f92faf2e511e1
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
Diffstat (limited to 'src/corelib/global/qglobalstatic.h')
| -rw-r--r-- | src/corelib/global/qglobalstatic.h | 43 |
1 files changed, 0 insertions, 43 deletions
diff --git a/src/corelib/global/qglobalstatic.h b/src/corelib/global/qglobalstatic.h index 674a2aea65..034ef274fa 100644 --- a/src/corelib/global/qglobalstatic.h +++ b/src/corelib/global/qglobalstatic.h @@ -55,17 +55,6 @@ enum GuardValues { }; } -#if !QT_CONFIG(thread) || defined(Q_COMPILER_THREADSAFE_STATICS) -// some compilers support thread-safe statics -// The IA-64 C++ ABI requires this, so we know that all GCC versions since 3.4 -// support it. C++11 also requires this behavior. -// Clang and Intel CC masquerade as GCC when compiling on Linux. -// -// Apple's libc++abi however uses a global lock for initializing local statics, -// which will block other threads also trying to initialize a local static -// until the constructor returns ... -// We better avoid these kind of problems by using our own locked implementation. - #if defined(Q_OS_UNIX) && defined(Q_CC_INTEL) // Work around Intel issue ID 6000058488: // local statics inside an inline function inside an anonymous namespace are global @@ -94,39 +83,7 @@ enum GuardValues { } holder; \ return &holder.value; \ } -#else -// We don't know if this compiler supports thread-safe global statics -// so use our own locked implementation -QT_END_NAMESPACE -#include <QtCore/qmutex.h> -#include <mutex> -QT_BEGIN_NAMESPACE - -#define Q_GLOBAL_STATIC_INTERNAL(ARGS) \ - Q_DECL_HIDDEN inline Type *innerFunction() \ - { \ - static Type *d; \ - static QBasicMutex mutex; \ - int x = guard.loadAcquire(); \ - if (Q_UNLIKELY(x >= QtGlobalStatic::Uninitialized)) { \ - const std::lock_guard<QBasicMutex> locker(mutex); \ - if (guard.loadRelaxed() == QtGlobalStatic::Uninitialized) { \ - d = new Type ARGS; \ - static struct Cleanup { \ - Cleanup() = default; \ - ~Cleanup() { \ - delete d; \ - guard.storeRelaxed(QtGlobalStatic::Destroyed); \ - } \ - Q_DISABLE_COPY_MOVE(Cleanup) \ - } cleanup; \ - guard.storeRelease(QtGlobalStatic::Initialized); \ - } \ - } \ - return d; \ - } -#endif // this class must be POD, unless the compiler supports thread-safe statics template <typename T, T *(&innerFunction)(), QBasicAtomicInt &guard> |