From 6ebe316635b7d4a2d8a82f79cc99eab95b0aabff Mon Sep 17 00:00:00 2001
From: Noel Grandin <noel.grandin@collabora.co.uk>
Date: Wed, 4 Sep 2024 20:02:14 +0200
Subject: [PATCH] tsan: data race

Atomic write of size 4 at 0x7254000f5f08 by thread T38 (mutexes: write M0, write M1, write M2):
0 configmgr::Access::acquireCounting()
1 configmgr::Components::initGlobalBroadcaster(configmgr::Modifications const&, rtl::Reference<configmgr::RootAccess> const&, configmgr::Broadcaster*)
2 configmgr::RootAccess::commitChanges()
3 non-virtual thunk to configmgr::RootAccess::commitChanges()
4 utl::OConfigurationTreeRoot::commit()
5 dbaccess::(anonymous namespace)::DatabaseRegistrations::registerDatabaseLocation(rtl::OUString const&, rtl::OUString const&)
6 non-virtual thunk to dbaccess::(anonymous namespace)::DatabaseRegistrations::registerDatabaseLocation(rtl::OUString const&, rtl::OUString const&)
7 dbaccess::ODatabaseContext::registerDatabaseLocation(rtl::OUString const&, rtl::OUString const&)
8 dbaccess::ODatabaseContext::registerObject(rtl::OUString const&, com::sun::star::uno::Reference<com::sun::star::uno::XInterface> const&)
9 non-virtual thunk to dbaccess::ODatabaseContext::registerObject(rtl::OUString const&, com::sun::star::uno::Reference<com::sun::star::uno::XInterface> const&)
10 gcc3::callVirtualMethod(void*, unsigned int, void*, _typelib_TypeDescriptionReference*, bool, unsigned long*, unsigned int, unsigned long*, double*)

Previous read of size 4 at 0x7254000f5f08 by main thread (mutexes: write M3, write M4):
0 cppu::OWeakObject::disposeWeakConnectionPoint()
1 cppu::OWeakObject::release()
2 configmgr::RootAccess::release()
3 non-virtual thunk to configmgr::RootAccess::release()
4 com::sun::star::uno::Reference<com::sun::star::util::XChangesBatch>::~Reference()
5 SvtLinguConfig::~SvtLinguConfig()
6 SwDoc::GetGCIterator()
7 SwDoc::StartGrammarChecking(bool)
8 sw::DocumentTimerManager::GetNextIdleJob()
9 sw::DocumentTimerManager::IsDocIdle()
10 sw::SwDocIdle::UpdateMinPeriod(unsigned long) const
11 Scheduler::CallbackTaskScheduling()

Change-Id: Idaf2707e5902338a873a325228e9c97e646ea768
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/172874
Tested-by: Jenkins
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>
---
 cppuhelper/source/weak.cxx | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/cppuhelper/source/weak.cxx b/cppuhelper/source/weak.cxx
index 6bb353faa9bd..446cdc0e43ba 100644
--- a/cppuhelper/source/weak.cxx
+++ b/cppuhelper/source/weak.cxx
@@ -27,6 +27,7 @@
 
 #include <com/sun/star/lang/DisposedException.hpp>
 
+#include <atomic>
 #include <algorithm>
 #include <vector>
 #include <mutex>
@@ -232,7 +233,7 @@ void SAL_CALL OWeakObject::release() noexcept
 
 void OWeakObject::disposeWeakConnectionPoint()
 {
-    OSL_PRECOND( m_refCount == 0, "OWeakObject::disposeWeakConnectionPoint: only to be called with a ref count of 0!" );
+    OSL_PRECOND( (atomic_thread_fence(std::memory_order_acquire), m_refCount == 0), "OWeakObject::disposeWeakConnectionPoint: only to be called with a ref count of 0!" );
     if (m_pWeakConnectionPoint != nullptr) {
         OWeakConnectionPoint * const p = m_pWeakConnectionPoint;
         m_pWeakConnectionPoint = nullptr;