QThreadDataPrivate: fix data race on canWait boolean.

postEvent() accesses it with the postEventList mutex locked, but
processEvent() was checking it without any mutex locked.

Change-Id: I31bbb50f7a1c337067b8e3de16ee7cd11400b517
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
(cherry picked from qtbase/bf3a5ccef13d568662f027be62280aba1f73bada)
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/src/corelib/thread/qthread_p.h b/src/corelib/thread/qthread_p.h
index 766c62a..49cb80e 100644
--- a/src/corelib/thread/qthread_p.h
+++ b/src/corelib/thread/qthread_p.h
@@ -222,6 +222,12 @@ public:
     void ref();
     void deref();
 
+    bool canWaitLocked()
+    {
+        QMutexLocker locker(&postEventList.mutex);
+        return canWait;
+    }
+
     QThread *thread;
     Qt::HANDLE threadId;
     bool quitNow;