Merge remote-tracking branch 'origin/5.6' into dev

Conflicts:
	tests/auto/corelib/io/qfile/tst_qfile.cpp
	tests/auto/corelib/io/qprocess/tst_qprocess.cpp
	tests/auto/corelib/tools/qversionnumber/qversionnumber.pro

Change-Id: Ia93ce500349d96a2fbf0b4a37b73f088cc505c6e

1 files changed, 6 insertions, 6 deletions

diff --git a/src/corelib/kernel/qcoreapplication.cpp b/src/corelib/kernel/qcoreapplication.cpp
index 3013db8b2e..53725c7f90 100644
--- a/src/corelib/kernel/qcoreapplication.cpp
+++ b/src/corelib/kernel/qcoreapplication.cpp
@@ -455,8 +455,8 @@ QCoreApplicationPrivate::QCoreApplicationPrivate(int &aargc, char **aargv, uint
     qt_application_thread_id = QThread::currentThreadId();
 #  endif
 
-    // note: this call to QThread::currentThread() may end up setting theMainThread!
-    if (QThread::currentThread() != theMainThread)
+    QThread *cur = QThread::currentThread(); // note: this may end up setting theMainThread!
+    if (cur != theMainThread)
         qWarning("WARNING: QApplication was not created in the main() thread.");
 #endif
 }
@@ -526,11 +526,11 @@ void QCoreApplicationPrivate::eventDispatcherReady()
 {
 }
 
-QThread *QCoreApplicationPrivate::theMainThread = 0;
+QBasicAtomicPointer<QThread> QCoreApplicationPrivate::theMainThread = Q_BASIC_ATOMIC_INITIALIZER(0);
 QThread *QCoreApplicationPrivate::mainThread()
 {
-    Q_ASSERT(theMainThread != 0);
-    return theMainThread;
+    Q_ASSERT(theMainThread.load() != 0);
+    return theMainThread.load();
 }
 
 bool QCoreApplicationPrivate::threadRequiresCoreApplication()
@@ -2759,7 +2759,7 @@ bool QCoreApplication::hasPendingEvents()
 QAbstractEventDispatcher *QCoreApplication::eventDispatcher()
 {
     if (QCoreApplicationPrivate::theMainThread)
-        return QCoreApplicationPrivate::theMainThread->eventDispatcher();
+        return QCoreApplicationPrivate::theMainThread.load()->eventDispatcher();
     return 0;
 }