QEventDispatcherUNIX: turn interrupt bool into an atomic int.

It's read and written by different threads, so this was a race.

Change-Id: Ieffaa169eb67f40dc935291b3994f9ff1c7e05f0
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

src/corelib/kernel/qeventdispatcher_unix.cpp

@@ -147,8 +147,6 @@ QEventDispatcherUNIXPrivate::QEventDispatcherUNIXPrivate()
         qFatal("QEventDispatcherUNIXPrivate(): Can not continue without a thread pipe");
 
     sn_highest = -1;
-
-    interrupt = false;
 }
 
 QEventDispatcherUNIXPrivate::~QEventDispatcherUNIXPrivate()
@@ -584,7 +582,7 @@ int QEventDispatcherUNIX::activateSocketNotifiers()
 bool QEventDispatcherUNIX::processEvents(QEventLoop::ProcessEventsFlags flags)
 {
     Q_D(QEventDispatcherUNIX);
-    d->interrupt = false;
+    d->interrupt.store(0);
 
     // we are awake, broadcast it
     emit awake();
@@ -592,13 +590,13 @@ bool QEventDispatcherUNIX::processEvents(QEventLoop::ProcessEventsFlags flags)
 
     int nevents = 0;
     const bool canWait = (d->threadData->canWait
-                          && !d->interrupt
+                          && !d->interrupt.load()
                           && (flags & QEventLoop::WaitForMoreEvents));
 
     if (canWait)
         emit aboutToBlock();
 
-    if (!d->interrupt) {
+    if (!d->interrupt.load()) {
         // return the maximum time we can wait for an event.
         timespec *tm = 0;
         timespec wait_tm = { 0l, 0l };
@@ -667,7 +665,7 @@ void QEventDispatcherUNIX::wakeUp()
 void QEventDispatcherUNIX::interrupt()
 {
     Q_D(QEventDispatcherUNIX);
-    d->interrupt = true;
+    d->interrupt.store(1);
     wakeUp();
 }
 

src/corelib/kernel/qeventdispatcher_unix_p.h

@@ -162,7 +162,7 @@ public:
     QSockNotType::List sn_pending_list;
 
     QAtomicInt wakeUps;
-    bool interrupt;
+    QAtomicInt interrupt; // bool
 };
 
 QT_END_NAMESPACE