1 files changed, 6 insertions, 1 deletions
diff --git a/src/corelib/kernel/qobject_p.h b/src/corelib/kernel/qobject_p.h
index feafcaf323..838a9aa8c5 100644
--- a/src/corelib/kernel/qobject_p.h
+++ b/src/corelib/kernel/qobject_p.h
@@ -374,7 +374,12 @@ public:
     }
 public:
     ExtraData *extraData;    // extra data set by the user
-    QThreadData *threadData; // id of the thread that owns the object
+    // This atomic requires acquire/release semantics in a few places,
+    // e.g. QObject::moveToThread must synchronize with QCoreApplication::postEvent,
+    // because postEvent is thread-safe.
+    // However, most of the code paths involving QObject are only reentrant and
+    // not thread-safe, so synchronization should not be necessary there.
+    QAtomicPointer<QThreadData> threadData; // id of the thread that owns the object
 
     using ConnectionDataPointer = QExplicitlySharedDataPointer<ConnectionData>;
     QAtomicPointer<ConnectionData> connections;