Cocoa QPA: Clean up 0 as pointer

We use nil for Objective-C null pointers and nullptr everywhere
else, including CoreFoundation and similar opaque types.

Change-Id: Id75c59413dec54bf4d8e83cf7ed0ff7f3d8bb480
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@qt.io>

36 files changed, 195 insertions, 199 deletions

diff --git a/src/plugins/platforms/cocoa/main.mm b/src/plugins/platforms/cocoa/main.mm
index f9bfdc7dc7..89ecdf46f9 100644
--- a/src/plugins/platforms/cocoa/main.mm
+++ b/src/plugins/platforms/cocoa/main.mm
@@ -60,7 +60,7 @@ QPlatformIntegration * QCocoaIntegrationPlugin::create(const QString& system, co
     if (system.compare(QLatin1String("cocoa"), Qt::CaseInsensitive) == 0)
         return new QCocoaIntegration(paramList);
 
-    return 0;
+    return nullptr;
 }
 
 QT_END_NAMESPACE
diff --git a/src/plugins/platforms/cocoa/qcocoaaccessibility.mm b/src/plugins/platforms/cocoa/qcocoaaccessibility.mm
index 0a773ced29..1b84a1f05f 100644
--- a/src/plugins/platforms/cocoa/qcocoaaccessibility.mm
+++ b/src/plugins/platforms/cocoa/qcocoaaccessibility.mm
@@ -311,7 +311,7 @@ NSString *getTranslatedAction(const QString &qtAction)
     //      NSAccessibilityCancelAction;
     //      NSAccessibilityDeleteAction;
 
-    return 0;
+    return nil;
 }
 
 
diff --git a/src/plugins/platforms/cocoa/qcocoaaccessibilityelement.mm b/src/plugins/platforms/cocoa/qcocoaaccessibilityelement.mm
index ad251a6a44..03dc895ffb 100644
--- a/src/plugins/platforms/cocoa/qcocoaaccessibilityelement.mm
+++ b/src/plugins/platforms/cocoa/qcocoaaccessibilityelement.mm
@@ -569,7 +569,7 @@ static void convertLineOffset(QAccessibleTextInterface *text, int *line, int *of
         return NSAccessibilityUnignoredAncestor(self);
 
     // find the deepest child at the point
-    QAccessibleInterface *childOfChildInterface = 0;
+    QAccessibleInterface *childOfChildInterface = nullptr;
     do {
         childOfChildInterface = childInterface->childAt(screenPoint.x(), screenPoint.y());
         if (childOfChildInterface && childOfChildInterface->isValid())
diff --git a/src/plugins/platforms/cocoa/qcocoaapplication.mm b/src/plugins/platforms/cocoa/qcocoaapplication.mm
index d0f27795b6..11f3bd0384 100644
--- a/src/plugins/platforms/cocoa/qcocoaapplication.mm
+++ b/src/plugins/platforms/cocoa/qcocoaapplication.mm
@@ -113,7 +113,7 @@ static const QByteArray q_macLocalEventType = QByteArrayLiteral("mac_generic_NSE
 static bool qt_filterEvent(NSEvent *event)
 {
     if (qApp && qApp->eventDispatcher()->
-            filterNativeEvent(q_macLocalEventType, static_cast<void*>(event), 0))
+            filterNativeEvent(q_macLocalEventType, static_cast<void*>(event), nullptr))
         return true;
 
     if ([event type] == NSApplicationDefined) {
diff --git a/src/plugins/platforms/cocoa/qcocoaclipboard.mm b/src/plugins/platforms/cocoa/qcocoaclipboard.mm
index b4745900dc..a35c153084 100644
--- a/src/plugins/platforms/cocoa/qcocoaclipboard.mm
+++ b/src/plugins/platforms/cocoa/qcocoaclipboard.mm
@@ -56,13 +56,13 @@ QMimeData *QCocoaClipboard::mimeData(QClipboard::Mode mode)
         pasteBoard->sync();
         return pasteBoard->mimeData();
     }
-    return 0;
+    return nullptr;
 }
 
 void QCocoaClipboard::setMimeData(QMimeData *data, QClipboard::Mode mode)
 {
     if (QMacPasteboard *pasteBoard = pasteboardForMode(mode)) {
-        if (data == 0) {
+        if (!data) {
             pasteBoard->clear();
         }
 
@@ -90,7 +90,7 @@ QMacPasteboard *QCocoaClipboard::pasteboardForMode(QClipboard::Mode mode) const
     else if (mode == QClipboard::FindBuffer)
         return m_find.data();
     else
-        return 0;
+        return nullptr;
 }
 
 void QCocoaClipboard::handleApplicationStateChanged(Qt::ApplicationState state)
diff --git a/src/plugins/platforms/cocoa/qcocoacolordialoghelper.mm b/src/plugins/platforms/cocoa/qcocoacolordialoghelper.mm
index 0e127902ae..d7850b1481 100644
--- a/src/plugins/platforms/cocoa/qcocoacolordialoghelper.mm
+++ b/src/plugins/platforms/cocoa/qcocoacolordialoghelper.mm
@@ -74,8 +74,8 @@ QT_NAMESPACE_ALIAS_OBJC_CLASS(QNSColorPanelDelegate);
 {
     self = [super init];
     mColorPanel = [NSColorPanel sharedColorPanel];
-    mHelper = 0;
-    mStolenContentView = 0;
+    mHelper = nullptr;
+    mStolenContentView = nil;
     mPanelButtons = nil;
     mResultCode = NSModalResponseCancel;
     mDialogIsExecuting = false;
@@ -115,9 +115,9 @@ QT_NAMESPACE_ALIAS_OBJC_CLASS(QNSColorPanelDelegate);
         [self restoreOriginalContentView];
     } else if (!mStolenContentView) {
         // steal the color panel's contents view
-        mStolenContentView = [mColorPanel contentView];
+        mStolenContentView = mColorPanel.contentView;
         [mStolenContentView retain];
-        [mColorPanel setContentView:0];
+        mColorPanel.contentView = nil;
 
         // create a new content view and add the stolen one as a subview
         mPanelButtons = [[QNSPanelContentsWrapper alloc] initWithPanelDelegate:self];
@@ -309,7 +309,7 @@ public:
     void cleanup(QCocoaColorDialogHelper *helper)
     {
         if (mDelegate->mHelper == helper)
-            mDelegate->mHelper = 0;
+            mDelegate->mHelper = nullptr;
     }
 
     bool exec()
diff --git a/src/plugins/platforms/cocoa/qcocoacursor.mm b/src/plugins/platforms/cocoa/qcocoacursor.mm
index c021128e4c..b14cf6d3ee 100644
--- a/src/plugins/platforms/cocoa/qcocoacursor.mm
+++ b/src/plugins/platforms/cocoa/qcocoacursor.mm
@@ -80,15 +80,15 @@ void QCocoaCursor::setPos(const QPoint &position)
     pos.x = position.x();
     pos.y = position.y();
 
-    CGEventRef e = CGEventCreateMouseEvent(0, kCGEventMouseMoved, pos, kCGMouseButtonLeft);
+    CGEventRef e = CGEventCreateMouseEvent(nullptr, kCGEventMouseMoved, pos, kCGMouseButtonLeft);
     CGEventPost(kCGHIDEventTap, e);
     CFRelease(e);
 }
 
 NSCursor *QCocoaCursor::convertCursor(QCursor *cursor)
 {
-    if (cursor == nullptr)
-        return 0;
+    if (!cursor)
+        return nil;
 
     const Qt::CursorShape newShape = cursor->shape();
     NSCursor *cocoaCursor;
@@ -138,11 +138,11 @@ NSCursor *QCocoaCursor::convertCursor(QCursor *cursor)
         cocoaCursor = m_cursors.value(newShape);
         if (cocoaCursor && cursor->shape() == Qt::BitmapCursor) {
             [cocoaCursor release];
-            cocoaCursor = 0;
+            cocoaCursor = nil;
         }
-        if (cocoaCursor == 0) {
+        if (!cocoaCursor) {
             cocoaCursor = createCursorData(cursor);
-            if (cocoaCursor == 0)
+            if (!cocoaCursor)
                 return [NSCursor arrowCursor];
 
             m_cursors.insert(newShape, cocoaCursor);
@@ -211,8 +211,8 @@ NSCursor *QCocoaCursor::createCursorData(QCursor *cursor)
         0x07, 0xf0, 0x0f, 0xf8, 0x0f, 0xf8, 0x01, 0xc0, 0x01, 0xc0, 0x01, 0xc0,
         0x01, 0xc0, 0x01, 0xc0, 0x01, 0xc0, 0x01, 0xc0 };
 #endif
-    const uchar *cursorData = 0;
-    const uchar *cursorMaskData = 0;
+    const uchar *cursorData = nullptr;
+    const uchar *cursorMaskData = nullptr;
     QPoint hotspot = cursor->hotSpot();
 
     switch (cursor->shape()) {
@@ -269,7 +269,7 @@ NSCursor *QCocoaCursor::createCursorData(QCursor *cursor)
 #endif
     default:
         qWarning("Qt: QCursor::update: Invalid cursor shape %d", cursor->shape());
-        return 0;
+        return nil;
     }
 
     // Create an NSCursor from image data if this a self-provided cursor.
@@ -279,7 +279,7 @@ NSCursor *QCocoaCursor::createCursorData(QCursor *cursor)
         return (createCursorFromBitmap(&bitmap, &mask, hotspot));
     }
 
-    return 0; // should not happen, all cases covered above
+    return nil; // should not happen, all cases covered above
 }
 
 NSCursor *QCocoaCursor::createCursorFromBitmap(const QBitmap *bitmap, const QBitmap *mask, const QPoint hotspot)
diff --git a/src/plugins/platforms/cocoa/qcocoadrag.mm b/src/plugins/platforms/cocoa/qcocoadrag.mm
index e1f36b47a1..09433194a6 100644
--- a/src/plugins/platforms/cocoa/qcocoadrag.mm
+++ b/src/plugins/platforms/cocoa/qcocoadrag.mm
@@ -50,10 +50,10 @@ QT_BEGIN_NAMESPACE
 static const int dragImageMaxChars = 26;
 
 QCocoaDrag::QCocoaDrag() :
-    m_drag(0)
+    m_drag(nullptr)
 {
-    m_lastEvent = 0;
-    m_lastView = 0;
+    m_lastEvent = nil;
+    m_lastView = nil;
 }
 
 QCocoaDrag::~QCocoaDrag()
@@ -73,7 +73,7 @@ QMimeData *QCocoaDrag::dragMimeData()
     if (m_drag)
         return m_drag->mimeData();
 
-    return 0;
+    return nullptr;
 }
 
 Qt::DropAction QCocoaDrag::defaultAction(Qt::DropActions possibleActions,
@@ -140,7 +140,7 @@ Qt::DropAction QCocoaDrag::drag(QDrag *o)
 
     NSPoint event_location = [m_lastEvent locationInWindow];
     NSWindow *theWindow = [m_lastEvent window];
-    Q_ASSERT(theWindow != nil);
+    Q_ASSERT(theWindow);
     event_location.x -= hotSpot.x();
     CGFloat flippedY = pmDeviceIndependentSize.height() - hotSpot.y();
     event_location.y -= flippedY;
@@ -157,7 +157,7 @@ Qt::DropAction QCocoaDrag::drag(QDrag *o)
 
     [nsimage release];
 
-    m_drag = 0;
+    m_drag = nullptr;
     return m_executed_drop_action;
 }
 
diff --git a/src/plugins/platforms/cocoa/qcocoaeventdispatcher.h b/src/plugins/platforms/cocoa/qcocoaeventdispatcher.h
index 2ffc1395ba..6d62447f33 100644
--- a/src/plugins/platforms/cocoa/qcocoaeventdispatcher.h
+++ b/src/plugins/platforms/cocoa/qcocoaeventdispatcher.h
@@ -110,8 +110,8 @@ class QCocoaEventDispatcher : public QAbstractEventDispatcher
     Q_DECLARE_PRIVATE(QCocoaEventDispatcher)
 
 public:
-    QCocoaEventDispatcher(QAbstractEventDispatcherPrivate &priv, QObject *parent = 0);
-    explicit QCocoaEventDispatcher(QObject *parent = 0);
+    QCocoaEventDispatcher(QAbstractEventDispatcherPrivate &priv, QObject *parent = nullptr);
+    explicit QCocoaEventDispatcher(QObject *parent = nullptr);
     ~QCocoaEventDispatcher();
 
     bool processEvents(QEventLoop::ProcessEventsFlags flags);
diff --git a/src/plugins/platforms/cocoa/qcocoaeventdispatcher.mm b/src/plugins/platforms/cocoa/qcocoaeventdispatcher.mm
index 06978fb3fc..611853642a 100644
--- a/src/plugins/platforms/cocoa/qcocoaeventdispatcher.mm
+++ b/src/plugins/platforms/cocoa/qcocoaeventdispatcher.mm
@@ -129,11 +129,11 @@ void QCocoaEventDispatcherPrivate::maybeStartCFRunLoopTimer()
 {
     if (timerInfoList.isEmpty()) {
         // no active timers, so the CFRunLoopTimerRef should not be active either
-        Q_ASSERT(runLoopTimerRef == 0);
+        Q_ASSERT(!runLoopTimerRef);
         return;
     }
 
-    if (runLoopTimerRef == 0) {
+    if (!runLoopTimerRef) {
         // start the CFRunLoopTimer
         CFAbsoluteTime ttf = CFAbsoluteTimeGetCurrent();
         CFTimeInterval interval;
@@ -150,11 +150,11 @@ void QCocoaEventDispatcherPrivate::maybeStartCFRunLoopTimer()
         }
 
         ttf += interval;
-        CFRunLoopTimerContext info = { 0, this, 0, 0, 0 };
+        CFRunLoopTimerContext info = { 0, this, nullptr, nullptr, nullptr };
         // create the timer with a large interval, as recommended by the CFRunLoopTimerSetNextFireDate()
         // documentation, since we will adjust the timer's time-to-fire as needed to keep Qt timers working
-        runLoopTimerRef = CFRunLoopTimerCreate(0, ttf, oneyear, 0, 0, QCocoaEventDispatcherPrivate::runLoopTimerCallback, &info);
-        Q_ASSERT(runLoopTimerRef != 0);
+        runLoopTimerRef = CFRunLoopTimerCreate(nullptr, ttf, oneyear, 0, 0, QCocoaEventDispatcherPrivate::runLoopTimerCallback, &info);
+        Q_ASSERT(runLoopTimerRef);
 
         CFRunLoopAddTimer(mainRunLoop(), runLoopTimerRef, kCFRunLoopCommonModes);
     } else {
@@ -180,12 +180,12 @@ void QCocoaEventDispatcherPrivate::maybeStartCFRunLoopTimer()
 
 void QCocoaEventDispatcherPrivate::maybeStopCFRunLoopTimer()
 {
-    if (runLoopTimerRef == 0)
+    if (!runLoopTimerRef)
         return;
 
     CFRunLoopTimerInvalidate(runLoopTimerRef);
     CFRelease(runLoopTimerRef);
-    runLoopTimerRef = 0;
+    runLoopTimerRef = nullptr;
 }
 
 void QCocoaEventDispatcher::registerTimer(int timerId, int interval, Qt::TimerType timerType, QObject *obj)
@@ -368,13 +368,13 @@ bool QCocoaEventDispatcher::processEvents(QEventLoop::ProcessEventsFlags flags)
             break;
 
         QMacAutoReleasePool pool;
-        NSEvent* event = 0;
+        NSEvent* event = nil;
 
         // First, send all previously excluded input events, if any:
         if (!excludeUserEvents) {
             while (!d->queuedUserInputEvents.isEmpty()) {
                 event = static_cast<NSEvent *>(d->queuedUserInputEvents.takeFirst());
-                if (!filterNativeEvent("NSEvent", event, 0)) {
+                if (!filterNativeEvent("NSEvent", event, nullptr)) {
                     [NSApp sendEvent:event];
                     retVal = true;
                 }
@@ -432,7 +432,7 @@ bool QCocoaEventDispatcher::processEvents(QEventLoop::ProcessEventsFlags flags)
             retVal = true;
         } else {
             int lastSerialCopy = d->lastSerial;
-            bool hadModalSession = d->currentModalSessionCached != 0;
+            const bool hadModalSession = d->currentModalSessionCached;
             // We cannot block the thread (and run in a tight loop).
             // Instead we will process all current pending events and return.
             d->ensureNSAppInitialized();
@@ -471,12 +471,12 @@ bool QCocoaEventDispatcher::processEvents(QEventLoop::ProcessEventsFlags flags)
                             d->queuedUserInputEvents.append(event);
                             continue;
                         }
-                        if (!filterNativeEvent("NSEvent", event, 0)) {
+                        if (!filterNativeEvent("NSEvent", event, nullptr)) {
                             [NSApp sendEvent:event];
                             retVal = true;
                         }
                     }
-                } while (!d->interrupt && event != nil);
+                } while (!d->interrupt && event);
             } else do {
                 // INVARIANT: No modal window is executing.
                 event = [NSApp nextEventMatchingMask:NSAnyEventMask
@@ -492,12 +492,12 @@ bool QCocoaEventDispatcher::processEvents(QEventLoop::ProcessEventsFlags flags)
                             continue;
                         }
                     }
-                    if (!filterNativeEvent("NSEvent", event, 0)) {
+                    if (!filterNativeEvent("NSEvent", event, nullptr)) {
                         [NSApp sendEvent:event];
                         retVal = true;
                     }
                 }
-            } while (!d->interrupt && event != nil);
+            } while (!d->interrupt && event);
 
             if ((d->processEventsFlags & QEventLoop::EventLoopExec) == 0) {
                 // when called "manually", always send posted events and timers
@@ -514,7 +514,7 @@ bool QCocoaEventDispatcher::processEvents(QEventLoop::ProcessEventsFlags flags)
             // event recursion to ensure that we spin the correct modal session.
             // We do the interruptLater at the end of the function to ensure that we don't
             // disturb the 'wait for more events' below (as deleteLater will post an event):
-            if (hadModalSession && d->currentModalSessionCached == 0)
+            if (hadModalSession && !d->currentModalSessionCached)
                 interruptLater = true;
         }
         bool canWait = (d->threadData->canWait
@@ -611,11 +611,11 @@ void QCocoaEventDispatcherPrivate::temporarilyStopAllModalSessions()
         QCocoaModalSessionInfo &info = cocoaModalSessionStack[i];
         if (info.session) {
             [NSApp endModalSession:info.session];
-            info.session = 0;
+            info.session = nullptr;
             [(NSWindow*) info.nswindow release];
         }
     }
-    currentModalSessionCached = 0;
+    currentModalSessionCached = nullptr;
 }
 
 NSModalSession QCocoaEventDispatcherPrivate::currentModalSession()
@@ -626,7 +626,7 @@ NSModalSession QCocoaEventDispatcherPrivate::currentModalSession()
         return currentModalSessionCached;
 
     if (cocoaModalSessionStack.isEmpty())
-        return 0;
+        return nullptr;
 
     int sessionCount = cocoaModalSessionStack.size();
     for (int i=0; i<sessionCount; ++i) {
@@ -728,9 +728,9 @@ void QCocoaEventDispatcherPrivate::cleanupModalSessions()
             currentModalSessionCached = info.session;
             break;
         }
-        currentModalSessionCached = 0;
+        currentModalSessionCached = nullptr;
         if (info.session) {
-            Q_ASSERT(info.nswindow != 0);
+            Q_ASSERT(info.nswindow);
             [NSApp endModalSession:info.session];
             [(NSWindow *)info.nswindow release];
         }
@@ -757,10 +757,10 @@ void QCocoaEventDispatcherPrivate::beginModalSession(QWindow *window)
     // currentModalSession). A QCocoaModalSessionInfo is considered pending to be stopped if
     // the window pointer is zero, and the session pointer is non-zero (it will be fully
     // stopped in cleanupModalSessions()).
-    QCocoaModalSessionInfo info = {window, 0, 0};
+    QCocoaModalSessionInfo info = {window, nullptr, nullptr};
     cocoaModalSessionStack.push(info);
     updateChildrenWorksWhenModal();
-    currentModalSessionCached = 0;
+    currentModalSessionCached = nullptr;
 }
 
 void QCocoaEventDispatcherPrivate::endModalSession(QWindow *window)
@@ -779,12 +779,12 @@ void QCocoaEventDispatcherPrivate::endModalSession(QWindow *window)
         if (!info.window)
             endedSessions++;
         if (info.window == window) {
-            info.window = 0;
+            info.window = nullptr;
             if (i + endedSessions == stackSize-1) {
                 // The top sessions ended. Interrupt the event dispatcher to
                 // start spinning the correct session immediately.
                 q->interrupt();
-                currentModalSessionCached = 0;
+                currentModalSessionCached = nullptr;
                 cleanupModalSessionsNeeded = true;
             }
         }
@@ -793,13 +793,13 @@ void QCocoaEventDispatcherPrivate::endModalSession(QWindow *window)
 
 QCocoaEventDispatcherPrivate::QCocoaEventDispatcherPrivate()
     : processEventsFlags(0),
-      runLoopTimerRef(0),
+      runLoopTimerRef(nullptr),
       blockSendPostedEvents(false),
       currentExecIsNSAppRun(false),
       nsAppRunCalledByQt(false),
       cleanupModalSessionsNeeded(false),
       processEventsCalled(0),
-      currentModalSessionCached(0),
+      currentModalSessionCached(nullptr),
       lastSerial(-1),
       interrupt(false)
 {
@@ -937,7 +937,7 @@ void QCocoaEventDispatcherPrivate::cancelWaitForMoreEvents()
     // events somewhere, we post a dummy event to wake it up:
     QMacAutoReleasePool pool;
     [NSApp postEvent:[NSEvent otherEventWithType:NSApplicationDefined location:NSZeroPoint
-        modifierFlags:0 timestamp:0. windowNumber:0 context:0
+        modifierFlags:0 timestamp:0. windowNumber:0 context:nil
         subtype:QtCocoaEventSubTypeWakeup data1:0 data2:0] atStart:NO];
 }
 
@@ -1019,7 +1019,7 @@ QCocoaEventDispatcher::~QCocoaEventDispatcher()
     CFRelease(d->firstTimeObserver);
 }
 
-QtCocoaInterruptDispatcher* QtCocoaInterruptDispatcher::instance = 0;
+QtCocoaInterruptDispatcher* QtCocoaInterruptDispatcher::instance = nullptr;
 
 QtCocoaInterruptDispatcher::QtCocoaInterruptDispatcher() : cancelled(false)
 {
@@ -1036,7 +1036,7 @@ QtCocoaInterruptDispatcher::~QtCocoaInterruptDispatcher()
 {
     if (cancelled)
         return;
-    instance = 0;
+    instance = nullptr;
     QCocoaEventDispatcher::instance()->interrupt();
 }
 
@@ -1046,7 +1046,7 @@ void QtCocoaInterruptDispatcher::cancelInterruptLater()
         return;
     instance->cancelled = true;
     delete instance;
-    instance = 0;
+    instance = nullptr;
 }
 
 void QtCocoaInterruptDispatcher::interruptLater()
diff --git a/src/plugins/platforms/cocoa/qcocoafiledialoghelper.mm b/src/plugins/platforms/cocoa/qcocoafiledialoghelper.mm
index 63af002c3c..bab673dd64 100644
--- a/src/plugins/platforms/cocoa/qcocoafiledialoghelper.mm
+++ b/src/plugins/platforms/cocoa/qcocoafiledialoghelper.mm
@@ -129,7 +129,7 @@ QT_NAMESPACE_ALIAS_OBJC_CLASS(QNSOpenSavePanelDelegate);
     } else {
         mSavePanel = [NSSavePanel savePanel];
         [mSavePanel setCanSelectHiddenExtension:YES];
-        mOpenPanel = 0;
+        mOpenPanel = nil;
     }
 
     if ([mSavePanel respondsToSelector:@selector(setLevel:)])
@@ -569,7 +569,7 @@ static QString strippedText(QString s)
 QT_BEGIN_NAMESPACE
 
 QCocoaFileDialogHelper::QCocoaFileDialogHelper()
-    :mDelegate(0)
+    : mDelegate(nil)
 {
 }
 
@@ -579,7 +579,7 @@ QCocoaFileDialogHelper::~QCocoaFileDialogHelper()
         return;
     QMacAutoReleasePool pool;
     [mDelegate release];
-    mDelegate = 0;
+    mDelegate = nil;
 }
 
 void QCocoaFileDialogHelper::QNSOpenSavePanelDelegate_selectionChanged(const QString &newPath)
diff --git a/src/plugins/platforms/cocoa/qcocoafontdialoghelper.mm b/src/plugins/platforms/cocoa/qcocoafontdialoghelper.mm
index 3010aa0870..29aaaae683 100644
--- a/src/plugins/platforms/cocoa/qcocoafontdialoghelper.mm
+++ b/src/plugins/platforms/cocoa/qcocoafontdialoghelper.mm
@@ -100,9 +100,9 @@ QT_NAMESPACE_ALIAS_OBJC_CLASS(QNSFontPanelDelegate);
 {
     if ((self = [super init])) {
         mFontPanel = [NSFontPanel sharedFontPanel];
-        mHelper = 0;
-        mStolenContentView = 0;
-        mPanelButtons = 0;
+        mHelper = nullptr;
+        mStolenContentView = nil;
+        mPanelButtons = nil;
         mResultCode = NSModalResponseCancel;
         mDialogIsExecuting = false;
         mResultSet = false;
@@ -136,9 +136,9 @@ QT_NAMESPACE_ALIAS_OBJC_CLASS(QNSFontPanelDelegate);
         [self restoreOriginalContentView];
     } else if (!mStolenContentView) {
         // steal the font panel's contents view
-        mStolenContentView = [mFontPanel contentView];
+        mStolenContentView = mFontPanel.contentView;
         [mStolenContentView retain];
-        [mFontPanel setContentView:0];
+        mFontPanel.contentView = nil;
 
         // create a new content view and add the stolen one as a subview
         mPanelButtons = [[QNSPanelContentsWrapper alloc] initWithPanelDelegate:self];
@@ -160,7 +160,7 @@ QT_NAMESPACE_ALIAS_OBJC_CLASS(QNSFontPanelDelegate);
         // return stolen stuff to its rightful owner
         [mStolenContentView removeFromSuperview];
         [mFontPanel setContentView:mStolenContentView];
-        mStolenContentView = 0;
+        mStolenContentView = nil;
         [mPanelButtons release];
         mPanelButtons = nil;
     }
@@ -192,7 +192,7 @@ QT_NAMESPACE_ALIAS_OBJC_CLASS(QNSFontPanelDelegate);
     // Get selected font
     NSFontManager *fontManager = [NSFontManager sharedFontManager];
     NSFont *selectedFont = [fontManager selectedFont];
-    if (selectedFont == nil) {
+    if (!selectedFont) {
         selectedFont = [NSFont systemFontOfSize:[NSFont systemFontSize]];
     }
     NSFont *panelFont = [fontManager convertFont:selectedFont];
@@ -296,7 +296,7 @@ public:
     void cleanup(QCocoaFontDialogHelper *helper)
     {
         if (mDelegate->mHelper == helper)
-            mDelegate->mHelper = 0;
+            mDelegate->mHelper = nullptr;
     }
 
     bool exec()
@@ -330,7 +330,7 @@ public:
     void setCurrentFont(const QFont &font)
     {
         NSFontManager *mgr = [NSFontManager sharedFontManager];
-        const NSFont *nsFont = 0;
+        NSFont *nsFont = nil;
 
         int weight = 5;
         NSFontTraitMask mask = 0;
@@ -348,7 +348,7 @@ public:
             weight:weight
             size:fontInfo.pointSize()];
 
-        [mgr setSelectedFont:const_cast<NSFont *>(nsFont) isMultiple:NO];
+        [mgr setSelectedFont:nsFont isMultiple:NO];
         mDelegate->mQtFont = font;
     }
 
diff --git a/src/plugins/platforms/cocoa/qcocoaglcontext.mm b/src/plugins/platforms/cocoa/qcocoaglcontext.mm
index b656025ec7..2493181bc5 100644
--- a/src/plugins/platforms/cocoa/qcocoaglcontext.mm
+++ b/src/plugins/platforms/cocoa/qcocoaglcontext.mm
@@ -386,7 +386,7 @@ void QCocoaGLContext::updateSurfaceFormat()
 void QCocoaGLContext::doneCurrent()
 {
     if (m_currentWindow && m_currentWindow.data()->handle())
-        static_cast<QCocoaWindow *>(m_currentWindow.data()->handle())->setCurrentContext(0);
+        static_cast<QCocoaWindow *>(m_currentWindow.data()->handle())->setCurrentContext(nullptr);
 
     m_currentWindow.clear();
 
diff --git a/src/plugins/platforms/cocoa/qcocoaintegration.mm b/src/plugins/platforms/cocoa/qcocoaintegration.mm
index a50b9251b7..9f4fd02139 100644
--- a/src/plugins/platforms/cocoa/qcocoaintegration.mm
+++ b/src/plugins/platforms/cocoa/qcocoaintegration.mm
@@ -94,11 +94,11 @@ static QCocoaIntegration::Options parseOptions(const QStringList &paramList)
     return options;
 }
 
-QCocoaIntegration *QCocoaIntegration::mInstance = 0;
+QCocoaIntegration *QCocoaIntegration::mInstance = nullptr;
 
 QCocoaIntegration::QCocoaIntegration(const QStringList &paramList)
     : mOptions(parseOptions(paramList))
-    , mFontDb(0)
+    , mFontDb(nullptr)
 #ifndef QT_NO_ACCESSIBILITY
     , mAccessibility(new QCocoaAccessibility)
 #endif
@@ -110,7 +110,7 @@ QCocoaIntegration::QCocoaIntegration(const QStringList &paramList)
     , mServices(new QCocoaServices)
     , mKeyboardMapper(new QCocoaKeyMapper)
 {
-    if (mInstance != 0)
+    if (mInstance)
         qWarning("Creating multiple Cocoa platform integrations is not supported");
     mInstance = this;
 
@@ -186,7 +186,7 @@ QCocoaIntegration::QCocoaIntegration(const QStringList &paramList)
 
 QCocoaIntegration::~QCocoaIntegration()
 {
-    mInstance = 0;
+    mInstance = nullptr;
 
     qt_resetNSApplicationSendEvent();
 
@@ -296,7 +296,7 @@ QCocoaScreen *QCocoaIntegration::screenForNSScreen(NSScreen *nsScreen)
 {
     NSUInteger index = [[NSScreen screens] indexOfObject:nsScreen];
     if (index == NSNotFound)
-        return 0;
+        return nullptr;
 
     if (index >= unsigned(mScreens.count()))
         updateScreens();
@@ -306,7 +306,7 @@ QCocoaScreen *QCocoaIntegration::screenForNSScreen(NSScreen *nsScreen)
             return screen;
     }
 
-    return 0;
+    return nullptr;
 }
 
 bool QCocoaIntegration::hasCapability(QPlatformIntegration::Capability cap) const
@@ -480,14 +480,14 @@ void QCocoaIntegration::pushPopupWindow(QCocoaWindow *window)
 QCocoaWindow *QCocoaIntegration::popPopupWindow()
 {
     if (m_popupWindowStack.isEmpty())
-        return 0;
+        return nullptr;
     return m_popupWindowStack.takeLast();
 }
 
 QCocoaWindow *QCocoaIntegration::activePopupWindow() const
 {
     if (m_popupWindowStack.isEmpty())
-        return 0;
+        return nullptr;
     return m_popupWindowStack.front();
 }
 
diff --git a/src/plugins/platforms/cocoa/qcocoaintrospection.h b/src/plugins/platforms/cocoa/qcocoaintrospection.h
index 1d984b9857..20001ac71d 100644
--- a/src/plugins/platforms/cocoa/qcocoaintrospection.h
+++ b/src/plugins/platforms/cocoa/qcocoaintrospection.h
@@ -76,7 +76,7 @@
 
 QT_BEGIN_NAMESPACE
 
-void qt_cocoa_change_implementation(Class baseClass, SEL originalSel, Class proxyClass, SEL replacementSel = 0, SEL backupSel = 0);
+void qt_cocoa_change_implementation(Class baseClass, SEL originalSel, Class proxyClass, SEL replacementSel = nil, SEL backupSel = nil);
 void qt_cocoa_change_back_implementation(Class baseClass, SEL originalSel, SEL backupSel);
 
 QT_END_NAMESPACE
diff --git a/src/plugins/platforms/cocoa/qcocoakeymapper.mm b/src/plugins/platforms/cocoa/qcocoakeymapper.mm
index 80140505d1..5408178824 100644
--- a/src/plugins/platforms/cocoa/qcocoakeymapper.mm
+++ b/src/plugins/platforms/cocoa/qcocoakeymapper.mm
@@ -357,17 +357,17 @@ Qt::KeyboardModifiers QCocoaKeyMapper::queryKeyboardModifiers()
 
 bool QCocoaKeyMapper::updateKeyboard()
 {
-    const UCKeyboardLayout *uchrData = 0;
+    const UCKeyboardLayout *uchrData = nullptr;
     QCFType<TISInputSourceRef> source = TISCopyInputMethodKeyboardLayoutOverride();
     if (!source)
         source = TISCopyCurrentKeyboardInputSource();
     if (keyboard_mode != NullMode && source == currentInputSource) {
         return false;
     }
-    Q_ASSERT(source != 0);
+    Q_ASSERT(source);
     CFDataRef data = static_cast<CFDataRef>(TISGetInputSourceProperty(source,
                                                                  kTISPropertyUnicodeKeyLayoutData));
-    uchrData = data ? reinterpret_cast<const UCKeyboardLayout *>(CFDataGetBytePtr(data)) : 0;
+    uchrData = data ? reinterpret_cast<const UCKeyboardLayout *>(CFDataGetBytePtr(data)) : nullptr;
 
     keyboard_kind = LMGetKbdType();
     if (uchrData) {
@@ -386,7 +386,7 @@ void QCocoaKeyMapper::deleteLayouts()
     for (int i = 0; i < 255; ++i) {
         if (keyLayout[i]) {
             delete keyLayout[i];
-            keyLayout[i] = 0;
+            keyLayout[i] = nullptr;
         }
     }
 }
diff --git a/src/plugins/platforms/cocoa/qcocoamenu.mm b/src/plugins/platforms/cocoa/qcocoamenu.mm
index ea28c305d6..cd1a960b4e 100644
--- a/src/plugins/platforms/cocoa/qcocoamenu.mm
+++ b/src/plugins/platforms/cocoa/qcocoamenu.mm
@@ -53,7 +53,7 @@
 QT_BEGIN_NAMESPACE
 
 QCocoaMenu::QCocoaMenu() :
-    m_attachedItem(0),
+    m_attachedItem(nil),
     m_updateTimer(0),
     m_enabled(true),
     m_parentEnabled(true),
@@ -69,7 +69,7 @@ QCocoaMenu::~QCocoaMenu()
 {
     foreach (QCocoaMenuItem *item, m_menuItems) {
         if (item->menuParent() == this)
-            item->setMenuParent(0);
+            item->setMenuParent(nullptr);
     }
 
     [m_nativeMenu release];
@@ -187,7 +187,7 @@ void QCocoaMenu::removeMenuItem(QPlatformMenuItem *menuItem)
     }
 
     if (cocoaItem->menuParent() == this)
-        cocoaItem->setMenuParent(0);
+        cocoaItem->setMenuParent(nullptr);
 
     // Ignore any parent enabled state
     cocoaItem->setParentEnabled(true);
@@ -335,11 +335,11 @@ void QCocoaMenu::showPopup(const QWindow *parentWindow, const QRect &targetRect,
     QMacAutoReleasePool pool;
 
     QPoint pos =  QPoint(targetRect.left(), targetRect.top() + targetRect.height());
-    QCocoaWindow *cocoaWindow = parentWindow ? static_cast<QCocoaWindow *>(parentWindow->handle()) : 0;
+    QCocoaWindow *cocoaWindow = parentWindow ? static_cast<QCocoaWindow *>(parentWindow->handle()) : nullptr;
     NSView *view = cocoaWindow ? cocoaWindow->view() : nil;
     NSMenuItem *nsItem = item ? ((QCocoaMenuItem *)item)->nsItem() : nil;
 
-    QScreen *screen = 0;
+    QScreen *screen = nullptr;
     if (parentWindow)
         screen = parentWindow->screen();
     if (!screen && !QGuiApplication::screens().isEmpty())
@@ -403,7 +403,7 @@ void QCocoaMenu::showPopup(const QWindow *parentWindow, const QRect &targetRect,
                                           pressure:1.0];
             [NSMenu popUpContextMenu:m_nativeMenu withEvent:menuEvent forView:view];
         } else {
-            [m_nativeMenu popUpMenuPositioningItem:nsItem atLocation:nsPos inView:0];
+            [m_nativeMenu popUpMenuPositioningItem:nsItem atLocation:nsPos inView:nil];
         }
     }
 
diff --git a/src/plugins/platforms/cocoa/qcocoamenubar.mm b/src/plugins/platforms/cocoa/qcocoamenubar.mm
index 1b6b5a5de6..871cf10e8a 100644
--- a/src/plugins/platforms/cocoa/qcocoamenubar.mm
+++ b/src/plugins/platforms/cocoa/qcocoamenubar.mm
@@ -79,7 +79,7 @@ QCocoaMenuBar::~QCocoaMenuBar()
     static_menubars.removeOne(this);
 
     if (!m_window.isNull() && m_window->menubar() == this) {
-        m_window->setMenubar(0);
+        m_window->setMenubar(nullptr);
 
         // Delete the children first so they do not cause
         // the native menu items to be hidden after
@@ -229,7 +229,7 @@ void QCocoaMenuBar::handleReparent(QWindow *newParentWindow)
     if (!m_window.isNull())
         m_window->setMenubar(nullptr);
 
-    if (newParentWindow == nullptr) {
+    if (!newParentWindow) {
         m_window.clear();
     } else {
         newParentWindow->create();
@@ -264,7 +264,7 @@ void QCocoaMenuBar::updateMenuBarImmediately()
     QCocoaMenuBar *mb = findGlobalMenubar();
     QCocoaWindow *cw = findWindowForMenubar();
 
-    QWindow *win = cw ? cw->window() : 0;
+    QWindow *win = cw ? cw->window() : nullptr;
     if (win && (win->flags() & Qt::Popup) == Qt::Popup) {
         // context menus, comboboxes, etc. don't need to update the menubar,
         // but if an application has only Qt::Tool window(s) on start,
diff --git a/src/plugins/platforms/cocoa/qcocoamenuitem.mm b/src/plugins/platforms/cocoa/qcocoamenuitem.mm
index ee70e059a1..30fde17abf 100644
--- a/src/plugins/platforms/cocoa/qcocoamenuitem.mm
+++ b/src/plugins/platforms/cocoa/qcocoamenuitem.mm
@@ -113,7 +113,7 @@ QCocoaMenuItem::~QCocoaMenuItem()
     QMacAutoReleasePool pool;
 
     if (m_menu && m_menu->menuParent() == this)
-        m_menu->setMenuParent(0);
+        m_menu->setMenuParent(nullptr);
     if (m_merged) {
         [m_native setHidden:YES];
     } else {
@@ -141,7 +141,7 @@ void QCocoaMenuItem::setMenu(QPlatformMenu *menu)
         return;
 
     if (m_menu && m_menu->menuParent() == this) {
-        m_menu->setMenuParent(0);
+        m_menu->setMenuParent(nullptr);
         // Free the menu from its parent's influence
         m_menu->propagateEnabledState(true);
         if (m_native && m_menu->attachedItem() == m_native)
diff --git a/src/plugins/platforms/cocoa/qcocoamenuloader.mm b/src/plugins/platforms/cocoa/qcocoamenuloader.mm
index 9bd6108d0d..4439587392 100644
--- a/src/plugins/platforms/cocoa/qcocoamenuloader.mm
+++ b/src/plugins/platforms/cocoa/qcocoamenuloader.mm
@@ -214,7 +214,7 @@
 #endif
     // Grab the app menu out of the current menu.
     int numItems = [mainMenu numberOfItems];
-    NSMenuItem *oldAppMenuItem = 0;
+    NSMenuItem *oldAppMenuItem = nil;
     for (int i = 0; i < numItems; ++i) {
         NSMenuItem *item = [mainMenu itemAtIndex:i];
         if ([item submenu] == appMenu) {
diff --git a/src/plugins/platforms/cocoa/qcocoanativeinterface.mm b/src/plugins/platforms/cocoa/qcocoanativeinterface.mm
index bdf8b5e1ff..b4af4a6e01 100644
--- a/src/plugins/platforms/cocoa/qcocoanativeinterface.mm
+++ b/src/plugins/platforms/cocoa/qcocoanativeinterface.mm
@@ -81,20 +81,20 @@ QCocoaNativeInterface::QCocoaNativeInterface()
 void *QCocoaNativeInterface::nativeResourceForContext(const QByteArray &resourceString, QOpenGLContext *context)
 {
     if (!context)
-        return 0;
+        return nullptr;
     if (resourceString.toLower() == "nsopenglcontext")
         return nsOpenGLContextForContext(context);
     if (resourceString.toLower() == "cglcontextobj")
         return cglContextForContext(context);
 
-    return 0;
+    return nullptr;
 }
 #endif
 
 void *QCocoaNativeInterface::nativeResourceForWindow(const QByteArray &resourceString, QWindow *window)
 {
     if (!window->handle())
-        return 0;
+        return nullptr;
 
     if (resourceString == "nsview") {
         return static_cast<QCocoaWindow *>(window->handle())->m_view;
@@ -105,7 +105,7 @@ void *QCocoaNativeInterface::nativeResourceForWindow(const QByteArray &resourceS
     } else if (resourceString == "nswindow") {
         return static_cast<QCocoaWindow *>(window->handle())->nativeWindow();
     }
-    return 0;
+    return nullptr;
 }
 
 QPlatformNativeInterface::NativeResourceForIntegrationFunction QCocoaNativeInterface::nativeResourceFunctionForIntegration(const QByteArray &resource)
@@ -143,7 +143,7 @@ QPlatformNativeInterface::NativeResourceForIntegrationFunction QCocoaNativeInter
     if (resource.toLower() == "testcontentborderposition")
         return NativeResourceForIntegrationFunction(QCocoaNativeInterface::testContentBorderPosition);
 
-    return 0;
+    return nullptr;
 }
 
 QPlatformPrinterSupport *QCocoaNativeInterface::createPlatformPrinterSupport()
@@ -152,7 +152,7 @@ QPlatformPrinterSupport *QCocoaNativeInterface::createPlatformPrinterSupport()
     return new QCocoaPrinterSupport();
 #else
     qFatal("Printing is not supported when Qt is configured with -no-widgets");
-    return 0;
+    return nullptr;
 #endif
 }
 
@@ -166,7 +166,7 @@ void *QCocoaNativeInterface::NSPrintInfoForPrintEngine(QPrintEngine *printEngine
 #else
     Q_UNUSED(printEngine);
     qFatal("Printing is not supported when Qt is configured with -no-widgets");
-    return 0;
+    return nullptr;
 #endif
 }
 
@@ -180,10 +180,10 @@ QPixmap QCocoaNativeInterface::defaultBackgroundPixmapForQWizard()
         CFURLRef url = (CFURLRef)CFArrayGetValueAtIndex(urls, 0);
         QCFType<CFBundleRef> bundle = CFBundleCreate(kCFAllocatorDefault, url);
         if (bundle) {
-            url = CFBundleCopyResourceURL(bundle, CFSTR("Background"), CFSTR("png"), 0);
+            url = CFBundleCopyResourceURL(bundle, CFSTR("Background"), CFSTR("png"), nullptr);
             if (url) {
-                QCFType<CGImageSourceRef> imageSource = CGImageSourceCreateWithURL(url, 0);
-                QCFType<CGImageRef> image = CGImageSourceCreateImageAtIndex(imageSource, 0, 0);
+                QCFType<CGImageSourceRef> imageSource = CGImageSourceCreateWithURL(url, nullptr);
+                QCFType<CGImageRef> image = CGImageSourceCreateImageAtIndex(imageSource, 0, nullptr);
                 if (image) {
                     int width = CGImageGetWidth(image);
                     int height = CGImageGetHeight(image);
@@ -213,7 +213,7 @@ void *QCocoaNativeInterface::cglContextForContext(QOpenGLContext* context)
     NSOpenGLContext *nsOpenGLContext = static_cast<NSOpenGLContext*>(nsOpenGLContextForContext(context));
     if (nsOpenGLContext)
         return [nsOpenGLContext CGLContextObj];
-    return 0;
+    return nullptr;
 }
 
 void *QCocoaNativeInterface::nsOpenGLContextForContext(QOpenGLContext* context)
@@ -224,7 +224,7 @@ void *QCocoaNativeInterface::nsOpenGLContextForContext(QOpenGLContext* context)
             return cocoaGLContext->nsOpenGLContext();
         }
     }
-    return 0;
+    return nullptr;
 }
 #endif
 
diff --git a/src/plugins/platforms/cocoa/qcocoaprintdevice.mm b/src/plugins/platforms/cocoa/qcocoaprintdevice.mm
index bfe6cd09b6..f21dfd7205 100644
--- a/src/plugins/platforms/cocoa/qcocoaprintdevice.mm
+++ b/src/plugins/platforms/cocoa/qcocoaprintdevice.mm
@@ -67,17 +67,17 @@ static QPrint::DuplexMode macToDuplexMode(const PMDuplexMode &mode)
 
 QCocoaPrintDevice::QCocoaPrintDevice()
     : QPlatformPrintDevice(),
-      m_printer(0),
-      m_session(0),
-      m_ppd(0)
+      m_printer(nullptr),
+      m_session(nullptr),
+      m_ppd(nullptr)
 {
 }
 
 QCocoaPrintDevice::QCocoaPrintDevice(const QString &id)
     : QPlatformPrintDevice(id),
-      m_printer(0),
-      m_session(0),
-      m_ppd(0)
+      m_printer(nullptr),
+      m_session(nullptr),
+      m_ppd(nullptr)
 {
     if (!id.isEmpty()) {
         m_printer = PMPrinterCreateFromPrinterID(id.toCFString());
@@ -443,7 +443,7 @@ bool QCocoaPrintDevice::openPpdFile()
 {
     if (m_ppd)
         ppdClose(m_ppd);
-    m_ppd = 0;
+    m_ppd = nullptr;
     CFURLRef ppdURL = NULL;
     char ppdPath[MAXPATHLEN];
     if (PMPrinterCopyDescriptionURL(m_printer, kPMPPDDescriptionType, &ppdURL) == noErr
@@ -470,7 +470,7 @@ PMPaper QCocoaPrintDevice::macPaper(const QPageSize &pageSize) const
     if (m_macPapers.contains(pageSize.key()))
         return m_macPapers.value(pageSize.key());
     // For any other page size, whether custom or just unsupported, needs to be a custom PMPaper
-    PMPaper paper = 0;
+    PMPaper paper = nullptr;
     PMPaperMargins paperMargins;
     paperMargins.left = m_customMargins.left();
     paperMargins.right = m_customMargins.right();
diff --git a/src/plugins/platforms/cocoa/qcocoascreen.mm b/src/plugins/platforms/cocoa/qcocoascreen.mm
index f5408d7c13..d639b56064 100644
--- a/src/plugins/platforms/cocoa/qcocoascreen.mm
+++ b/src/plugins/platforms/cocoa/qcocoascreen.mm
@@ -164,7 +164,7 @@ QWindow *QCocoaScreen::topLevelAt(const QPoint &point) const
     // belowWindowWithWindowNumber] may return windows that are not interesting
     // to Qt. The search iterates until a suitable window or no window is found.
     NSInteger topWindowNumber = 0;
-    QWindow *window = 0;
+    QWindow *window = nullptr;
     do {
         // Get the top-most window, below any previously rejected window.
         topWindowNumber = [NSWindow windowNumberAtPoint:screenPoint
@@ -172,7 +172,7 @@ QWindow *QCocoaScreen::topLevelAt(const QPoint &point) const
 
         // Continue the search if the window does not belong to this process.
         NSWindow *nsWindow = [NSApp windowWithWindowNumber:topWindowNumber];
-        if (nsWindow == 0)
+        if (!nsWindow)
             continue;
 
         // Continue the search if the window does not belong to Qt.
diff --git a/src/plugins/platforms/cocoa/qcocoasystemsettings.mm b/src/plugins/platforms/cocoa/qcocoasystemsettings.mm
index 7c6f879b18..1aa7b188a6 100644
--- a/src/plugins/platforms/cocoa/qcocoasystemsettings.mm
+++ b/src/plugins/platforms/cocoa/qcocoasystemsettings.mm
@@ -129,7 +129,7 @@ QHash<QPlatformTheme::Palette, QPalette*> qt_mac_createRolePalettes()
     QColor qc;
     for (int i = 0; i < mac_widget_colors_count; i++) {
         QPalette &pal = *qt_mac_createSystemPalette();
-        if (mac_widget_colors[i].active != 0) {
+        if (mac_widget_colors[i].active) {
             qc = qt_mac_toQColor(mac_widget_colors[i].active);
             pal.setColor(QPalette::Active, QPalette::Text, qc);
             pal.setColor(QPalette::Inactive, QPalette::Text, qc);
diff --git a/src/plugins/platforms/cocoa/qcocoasystemtrayicon.h b/src/plugins/platforms/cocoa/qcocoasystemtrayicon.h
index 2f1a1e42a9..d831612c22 100644
--- a/src/plugins/platforms/cocoa/qcocoasystemtrayicon.h
+++ b/src/plugins/platforms/cocoa/qcocoasystemtrayicon.h
@@ -55,7 +55,7 @@ class QSystemTrayIconSys;
 class Q_GUI_EXPORT QCocoaSystemTrayIcon : public QPlatformSystemTrayIcon
 {
 public:
-    QCocoaSystemTrayIcon() : m_sys(0) {}
+    QCocoaSystemTrayIcon() : m_sys(nullptr) {}
 
     void init() override;
     void cleanup() override;
diff --git a/src/plugins/platforms/cocoa/qcocoasystemtrayicon.mm b/src/plugins/platforms/cocoa/qcocoasystemtrayicon.mm
index d3aafa3785..773f4b833f 100644
--- a/src/plugins/platforms/cocoa/qcocoasystemtrayicon.mm
+++ b/src/plugins/platforms/cocoa/qcocoasystemtrayicon.mm
@@ -147,7 +147,7 @@ QRect QCocoaSystemTrayIcon::geometry() const
 void QCocoaSystemTrayIcon::cleanup()
 {
     delete m_sys;
-    m_sys = 0;
+    m_sys = nullptr;
 }
 
 static bool heightCompareFunction (QSize a, QSize b) { return (a.height() < b.height()); }
@@ -363,7 +363,7 @@ QT_END_NAMESPACE
     self = [super init];
     if (self) {
         item = [[[NSStatusBar systemStatusBar] statusItemWithLength:NSSquareStatusItemLength] retain];
-        menu = 0;
+        menu = nullptr;
         systray = sys;
         imageCell = [[QNSImageView alloc] initWithParent:self];
         [item setView: imageCell];
diff --git a/src/plugins/platforms/cocoa/qcocoatheme.mm b/src/plugins/platforms/cocoa/qcocoatheme.mm
index d9e793c290..0f1bfea7b5 100644
--- a/src/plugins/platforms/cocoa/qcocoatheme.mm
+++ b/src/plugins/platforms/cocoa/qcocoatheme.mm
@@ -105,7 +105,7 @@ QT_BEGIN_NAMESPACE
 const char *QCocoaTheme::name = "cocoa";
 
 QCocoaTheme::QCocoaTheme()
-    :m_systemPalette(0)
+    : m_systemPalette(nullptr)
 {
     m_notificationReceiver = [[QT_MANGLE_NAMESPACE(QCocoaThemeNotificationReceiver) alloc] initWithPrivate:this];
     [[NSNotificationCenter defaultCenter] addObserver:m_notificationReceiver
@@ -145,7 +145,7 @@ bool QCocoaTheme::usePlatformNativeDialog(DialogType dialogType) const
     return false;
 }
 
-QPlatformDialogHelper * QCocoaTheme::createPlatformDialogHelper(DialogType dialogType) const
+QPlatformDialogHelper *QCocoaTheme::createPlatformDialogHelper(DialogType dialogType) const
 {
     switch (dialogType) {
 #if defined(QT_WIDGETS_LIB) && QT_CONFIG(filedialog)
@@ -161,7 +161,7 @@ QPlatformDialogHelper * QCocoaTheme::createPlatformDialogHelper(DialogType dialo
         return new QCocoaFontDialogHelper();
 #endif
     default:
-        return 0;
+        return nullptr;
     }
 }
 
@@ -181,9 +181,9 @@ const QPalette *QCocoaTheme::palette(Palette type) const
     } else {
         if (m_palettes.isEmpty())
             m_palettes = qt_mac_createRolePalettes();
-        return m_palettes.value(type, 0);
+        return m_palettes.value(type, nullptr);
     }
-    return 0;
+    return nullptr;
 }
 
 QHash<QPlatformTheme::Font, QFont *> qt_mac_createRoleFonts()
@@ -197,7 +197,7 @@ const QFont *QCocoaTheme::font(Font type) const
     if (m_fonts.isEmpty()) {
         m_fonts = qt_mac_createRoleFonts();
     }
-    return m_fonts.value(type, 0);
+    return m_fonts.value(type, nullptr);
 }
 
 //! \internal
diff --git a/src/plugins/platforms/cocoa/qcocoawindow.mm b/src/plugins/platforms/cocoa/qcocoawindow.mm
index 02a87709de..0ef06ccea7 100644
--- a/src/plugins/platforms/cocoa/qcocoawindow.mm
+++ b/src/plugins/platforms/cocoa/qcocoawindow.mm
@@ -143,7 +143,7 @@ const int QCocoaWindow::NoAlertRequest = -1;
 QCocoaWindow::QCocoaWindow(QWindow *win, WId nativeHandle)
     : QPlatformWindow(win)
     , m_view(nil)
-    , m_nsWindow(0)
+    , m_nsWindow(nil)
     , m_lastReportedWindowState(Qt::WindowNoState)
     , m_windowModality(Qt::NonModal)
     , m_windowUnderMouse(false)
@@ -152,9 +152,9 @@ QCocoaWindow::QCocoaWindow(QWindow *win, WId nativeHandle)
     , m_inSetGeometry(false)
     , m_inSetStyleMask(false)
 #ifndef QT_NO_OPENGL
-    , m_glContext(0)
+    , m_glContext(nullptr)
 #endif
-    , m_menubar(0)
+    , m_menubar(nullptr)
     , m_needsInvalidateShadow(false)
     , m_hasModalSession(false)
     , m_frameStrutEventsEnabled(false)
@@ -316,7 +316,7 @@ void QCocoaWindow::setVisible(bool visible)
     m_inSetVisible = true;
 
     QMacAutoReleasePool pool;
-    QCocoaWindow *parentCocoaWindow = 0;
+    QCocoaWindow *parentCocoaWindow = nullptr;
     if (window()->transientParent())
         parentCocoaWindow = static_cast<QCocoaWindow *>(window()->transientParent()->handle());
 
@@ -368,13 +368,13 @@ void QCocoaWindow::setVisible(bool visible)
                 } else if (window()->modality() != Qt::NonModal) {
                     // show the window as application modal
                     QCocoaEventDispatcher *cocoaEventDispatcher = qobject_cast<QCocoaEventDispatcher *>(QGuiApplication::instance()->eventDispatcher());
-                    Q_ASSERT(cocoaEventDispatcher != 0);
+                    Q_ASSERT(cocoaEventDispatcher);
                     QCocoaEventDispatcherPrivate *cocoaEventDispatcherPrivate = static_cast<QCocoaEventDispatcherPrivate *>(QObjectPrivate::get(cocoaEventDispatcher));
                     cocoaEventDispatcherPrivate->beginModalSession(window());
                     m_hasModalSession = true;
                 } else if ([m_view.window canBecomeKeyWindow]) {
                     QCocoaEventDispatcher *cocoaEventDispatcher = qobject_cast<QCocoaEventDispatcher *>(QGuiApplication::instance()->eventDispatcher());
-                    QCocoaEventDispatcherPrivate *cocoaEventDispatcherPrivate = 0;
+                    QCocoaEventDispatcherPrivate *cocoaEventDispatcherPrivate = nullptr;
                     if (cocoaEventDispatcher)
                         cocoaEventDispatcherPrivate = static_cast<QCocoaEventDispatcherPrivate *>(QObjectPrivate::get(cocoaEventDispatcher));
 
@@ -413,7 +413,7 @@ void QCocoaWindow::setVisible(bool visible)
             m_glContext->windowWasHidden();
 #endif
         QCocoaEventDispatcher *cocoaEventDispatcher = qobject_cast<QCocoaEventDispatcher *>(QGuiApplication::instance()->eventDispatcher());
-        QCocoaEventDispatcherPrivate *cocoaEventDispatcherPrivate = 0;
+        QCocoaEventDispatcherPrivate *cocoaEventDispatcherPrivate = nullptr;
         if (cocoaEventDispatcher)
             cocoaEventDispatcherPrivate = static_cast<QCocoaEventDispatcherPrivate *>(QObjectPrivate::get(cocoaEventDispatcher));
         if (isContentView()) {
@@ -481,7 +481,8 @@ NSInteger QCocoaWindow::windowLevel(Qt::WindowFlags flags)
     // Any "special" window should be in at least the same level as its parent.
     if (type != Qt::Window) {
         const QWindow * const transientParent = window()->transientParent();
-        const QCocoaWindow * const transientParentWindow = transientParent ? static_cast<QCocoaWindow *>(transientParent->handle()) : 0;
+        const QCocoaWindow * const transientParentWindow = transientParent ?
+                    static_cast<QCocoaWindow *>(transientParent->handle()) : nullptr;
         if (transientParentWindow)
             windowLevel = qMax([transientParentWindow->nativeWindow() level], windowLevel);
     }
@@ -1276,18 +1277,13 @@ void QCocoaWindow::recreateWindowIfNeeded()
                 // with a NSWindow contentView pointing to a deallocated NSView.
                 m_view.window.contentView = nil;
             }
-            m_nsWindow = 0;
+            m_nsWindow = nil;
         }
     }
 
-    if (shouldBeContentView) {
-        bool noPreviousWindow = m_nsWindow == 0;
-        QCocoaNSWindow *newWindow = nullptr;
-        if (noPreviousWindow)
-            newWindow = createNSWindow(shouldBePanel);
-
+    if (shouldBeContentView && !m_nsWindow) {
         // Move view to new NSWindow if needed
-        if (newWindow) {
+        if (auto *newWindow = createNSWindow(shouldBePanel)) {
             qCDebug(lcQpaWindow) << "Ensuring that" << m_view << "is content view for" << newWindow;
             [m_view setPostsFrameChangedNotifications:NO];
             [newWindow setContentView:m_view];
diff --git a/src/plugins/platforms/cocoa/qmacclipboard.h b/src/plugins/platforms/cocoa/qmacclipboard.h
index 1d229a55d2..f2f460c048 100644
--- a/src/plugins/platforms/cocoa/qmacclipboard.h
+++ b/src/plugins/platforms/cocoa/qmacclipboard.h
@@ -54,7 +54,7 @@ public:
     enum DataRequestType { EagerRequest, LazyRequest };
 private:
     struct Promise {
-        Promise() : itemId(0), convertor(0) { }
+        Promise() : itemId(0), convertor(nullptr) { }
 
         static Promise eagerPromise(int itemId, QMacInternalPasteboardMime *c, QString m, QMacMimeData *d, int o = 0);
         static Promise lazyPromise(int itemId, QMacInternalPasteboardMime *c, QString m, QMacMimeData *d, int o = 0);
@@ -79,7 +79,7 @@ private:
 public:
     QMacPasteboard(PasteboardRef p, uchar mime_type=0);
     QMacPasteboard(uchar mime_type);
-    QMacPasteboard(CFStringRef name=0, uchar mime_type=0);
+    QMacPasteboard(CFStringRef name=nullptr, uchar mime_type=0);
     ~QMacPasteboard();
 
     bool hasFlavor(QString flavor) const;
diff --git a/src/plugins/platforms/cocoa/qmacclipboard.mm b/src/plugins/platforms/cocoa/qmacclipboard.mm
index f3467fdc73..5939003c64 100644
--- a/src/plugins/platforms/cocoa/qmacclipboard.mm
+++ b/src/plugins/platforms/cocoa/qmacclipboard.mm
@@ -75,7 +75,7 @@ QMacPasteboard::Promise::Promise(int itemId, QMacInternalPasteboardMime *c, QStr
     // Request the data from the application immediately for eager requests.
     if (dataRequestType == QMacPasteboard::EagerRequest) {
         variantData = md->variantData(m);
-        mimeData = 0;
+        mimeData = nullptr;
     } else {
         mimeData = md;
     }
@@ -94,8 +94,8 @@ QMacPasteboard::QMacPasteboard(uchar mt)
 {
     mac_mime_source = false;
     mime_type = mt ? mt : uchar(QMacInternalPasteboardMime::MIME_ALL);
-    paste = 0;
-    OSStatus err = PasteboardCreate(0, &paste);
+    paste = nullptr;
+    OSStatus err = PasteboardCreate(nullptr, &paste);
     if (err == noErr) {
         PasteboardSetPromiseKeeper(paste, promiseKeeper, this);
     } else {
@@ -108,7 +108,7 @@ QMacPasteboard::QMacPasteboard(CFStringRef name, uchar mt)
 {
     mac_mime_source = false;
     mime_type = mt ? mt : uchar(QMacInternalPasteboardMime::MIME_ALL);
-    paste = 0;
+    paste = nullptr;
     OSStatus err = PasteboardCreate(name, &paste);
     if (err == noErr) {
         PasteboardSetPromiseKeeper(paste, promiseKeeper, this);
@@ -165,7 +165,7 @@ OSStatus QMacPasteboard::promiseKeeper(PasteboardRef paste, PasteboardItemID id,
         // we have promised this data, but won't be able to convert, so return null data.
         // This helps in making the application/x-qt-mime-type-name hidden from normal use.
         QByteArray ba;
-        QCFType<CFDataRef> data = CFDataCreate(0, (UInt8*)ba.constData(), ba.size());
+        QCFType<CFDataRef> data = CFDataCreate(nullptr, (UInt8*)ba.constData(), ba.size());
         PasteboardPutItemFlavor(paste, id, flavor, data, kPasteboardFlavorNoFlags);
         return noErr;
     }
@@ -196,7 +196,7 @@ OSStatus QMacPasteboard::promiseKeeper(PasteboardRef paste, PasteboardItemID id,
     if (md.size() <= promise.offset)
         return cantGetFlavorErr;
     const QByteArray &ba = md[promise.offset];
-    QCFType<CFDataRef> data = CFDataCreate(0, (UInt8*)ba.constData(), ba.size());
+    QCFType<CFDataRef> data = CFDataCreate(nullptr, (UInt8*)ba.constData(), ba.size());
     PasteboardPutItemFlavor(paste, id, flavor, data, kPasteboardFlavorNoFlags);
     return noErr;
 }
@@ -553,7 +553,7 @@ QMacPasteboard::sync() const
     const bool fromGlobal = PasteboardSynchronize(paste) & kPasteboardModified;
 
     if (fromGlobal)
-        const_cast<QMacPasteboard *>(this)->setMimeData(0);
+        const_cast<QMacPasteboard *>(this)->setMimeData(nullptr);
 
 #ifdef DEBUG_PASTEBOARD
     if (fromGlobal)
diff --git a/src/plugins/platforms/cocoa/qmultitouch_mac.mm b/src/plugins/platforms/cocoa/qmultitouch_mac.mm
index 9eca4d2d43..10652dc6a1 100644
--- a/src/plugins/platforms/cocoa/qmultitouch_mac.mm
+++ b/src/plugins/platforms/cocoa/qmultitouch_mac.mm
@@ -107,7 +107,7 @@ QCocoaTouch *QCocoaTouch::findQCocoaTouch(NSTouch *nstouch)
     qint64 identity = qint64([nstouch identity]);
     if (_currentTouches.contains(identity))
         return _currentTouches.value(identity);
-    return 0;
+    return nullptr;
 }
 
 Qt::TouchPointState QCocoaTouch::toTouchPointState(NSTouchPhase nsState)
diff --git a/src/plugins/platforms/cocoa/qnsview.mm b/src/plugins/platforms/cocoa/qnsview.mm
index ff3ab8aae7..c30c6c7386 100644
--- a/src/plugins/platforms/cocoa/qnsview.mm
+++ b/src/plugins/platforms/cocoa/qnsview.mm
@@ -148,18 +148,18 @@
         m_frameStrutButtons = Qt::NoButton;
         m_sendKeyEvent = false;
 #ifndef QT_NO_OPENGL
-        m_glContext = 0;
+        m_glContext = nullptr;
         m_shouldSetGLContextinDrawRect = false;
 #endif
-        currentCustomDragTypes = 0;
+        currentCustomDragTypes = nullptr;
         m_dontOverrideCtrlLMB = false;
         m_sendUpAsRightButton = false;
-        m_inputSource = 0;
+        m_inputSource = nil;
         m_mouseMoveHelper = [[QT_MANGLE_NAMESPACE(QNSViewMouseMoveHelper) alloc] initWithView:self];
         m_resendKeyEvent = false;
         m_scrolling = false;
         m_updatingDrag = false;
-        m_currentlyInterpretedKeyEvent = 0;
+        m_currentlyInterpretedKeyEvent = nil;
         self.focusRingType = NSFocusRingTypeNone;
         self.cursor = nil;
         m_updateRequested = false;
diff --git a/src/plugins/platforms/cocoa/qpaintengine_mac.mm b/src/plugins/platforms/cocoa/qpaintengine_mac.mm
index 3f363b62d5..96506c67fa 100644
--- a/src/plugins/platforms/cocoa/qpaintengine_mac.mm
+++ b/src/plugins/platforms/cocoa/qpaintengine_mac.mm
@@ -98,8 +98,8 @@ CGImageRef qt_mac_create_imagemask(const QPixmap &pixmap, const QRectF &sr)
         for (int x = sx; x < sw; ++x)
             *(dptr+(offset++)) = (*(srow+x) & mask) ? 255 : 0;
     }
-    QCFType<CGDataProviderRef> provider = CGDataProviderCreateWithData(0, dptr, nbytes, qt_mac_cgimage_data_free);
-    return CGImageMaskCreate(sw, sh, 8, 8, nbytes / sh, provider, 0, 0);
+    QCFType<CGDataProviderRef> provider = CGDataProviderCreateWithData(nullptr, dptr, nbytes, qt_mac_cgimage_data_free);
+    return CGImageMaskCreate(sw, sh, 8, 8, nbytes / sh, provider, nullptr, false);
 }
 
 //conversion
@@ -287,16 +287,16 @@ static void qt_mac_draw_pattern(void *info, CGContextRef c)
             Q_ASSERT(pat->data.bytes);
             w = h = 8;
 #if (QMACPATTERN_MASK_MULTIPLIER == 1)
-            CGDataProviderRef provider = CGDataProviderCreateWithData(0, pat->data.bytes, w*h, 0);
-            pat->image = CGImageMaskCreate(w, h, 1, 1, 1, provider, 0, false);
+            CGDataProviderRef provider = CGDataProviderCreateWithData(nullptr, pat->data.bytes, w*h, nullptr);
+            pat->image = CGImageMaskCreate(w, h, 1, 1, 1, provider, nullptr, false);
             CGDataProviderRelease(provider);
 #else
             const int numBytes = (w*h)/sizeof(uchar);
             uchar xor_bytes[numBytes];
             for (int i = 0; i < numBytes; ++i)
                 xor_bytes[i] = pat->data.bytes[i] ^ 0xFF;
-            CGDataProviderRef provider = CGDataProviderCreateWithData(0, xor_bytes, w*h, 0);
-            CGImageRef swatch = CGImageMaskCreate(w, h, 1, 1, 1, provider, 0, false);
+            CGDataProviderRef provider = CGDataProviderCreateWithData(nullptr, xor_bytes, w*h, nullptr);
+            CGImageRef swatch = CGImageMaskCreate(w, h, 1, 1, 1, provider, nullptr, false);
             CGDataProviderRelease(provider);
 
             const QColor c0(0, 0, 0, 0), c1(255, 255, 255, 255);
@@ -399,9 +399,9 @@ QCoreGraphicsPaintEngine::begin(QPaintDevice *pdev)
         d->orig_xform = CGContextGetCTM(d->hd);
         if (d->shading) {
             CGShadingRelease(d->shading);
-            d->shading = 0;
+            d->shading = nullptr;
         }
-        d->setClip(0);  //clear the context's clipping
+        d->setClip(nullptr);  //clear the context's clipping
     }
 
     setActive(true);
@@ -445,12 +445,12 @@ QCoreGraphicsPaintEngine::end()
         CGShadingRelease(d->shading);
         d->shading = 0;
     }
-    d->pdev = 0;
+    d->pdev = nullptr;
     if (d->hd) {
         d->restoreGraphicsState();
         CGContextSynchronize(d->hd);
         CGContextRelease(d->hd);
-        d->hd = 0;
+        d->hd = nullptr;
     }
     return true;
 }
@@ -545,7 +545,7 @@ QCoreGraphicsPaintEngine::updateBrush(const QBrush &brush, const QPointF &brushO
 
     if (d->shading) {
         CGShadingRelease(d->shading);
-        d->shading = 0;
+        d->shading = nullptr;
     }
     d->setFillBrush(brushOrigin);
 }
@@ -592,7 +592,7 @@ QCoreGraphicsPaintEngine::updateClipPath(const QPainterPath &p, Qt::ClipOperatio
         if (d->current.clipEnabled) {
             d->current.clipEnabled = false;
             d->current.clip = QRegion();
-            d->setClip(0);
+            d->setClip(nullptr);
         }
     } else {
         if (!d->current.clipEnabled)
@@ -601,7 +601,7 @@ QCoreGraphicsPaintEngine::updateClipPath(const QPainterPath &p, Qt::ClipOperatio
         QRegion clipRegion(p.toFillPolygon().toPolygon(), p.fillRule());
         if (op == Qt::ReplaceClip) {
             d->current.clip = clipRegion;
-            d->setClip(0);
+            d->setClip(nullptr);
             if (p.isEmpty()) {
                 CGRect rect = CGRectMake(0, 0, 0, 0);
                 CGContextClipToRect(d->hd, rect);
@@ -630,7 +630,7 @@ QCoreGraphicsPaintEngine::updateClipRegion(const QRegion &clipRegion, Qt::ClipOp
     if (op == Qt::NoClip) {
         d->current.clipEnabled = false;
         d->current.clip = QRegion();
-        d->setClip(0);
+        d->setClip(nullptr);
     } else {
         if (!d->current.clipEnabled)
             op = Qt::ReplaceClip;
@@ -676,7 +676,7 @@ QCoreGraphicsPaintEngine::drawRects(const QRectF *rects, int rectCount)
         QRectF r = rects[i];
 
         CGMutablePathRef path = CGPathCreateMutable();
-        CGPathAddRect(path, 0, qt_mac_compose_rect(r));
+        CGPathAddRect(path, nullptr, qt_mac_compose_rect(r));
         d->drawPath(QCoreGraphicsPaintEnginePrivate::CGFill|QCoreGraphicsPaintEnginePrivate::CGStroke,
                 path);
         CGPathRelease(path);
@@ -698,8 +698,8 @@ QCoreGraphicsPaintEngine::drawPoints(const QPointF *points, int pointCount)
     CGMutablePathRef path = CGPathCreateMutable();
     for (int i=0; i < pointCount; i++) {
         float x = points[i].x(), y = points[i].y();
-        CGPathMoveToPoint(path, 0, x, y);
-        CGPathAddLineToPoint(path, 0, x+0.001, y);
+        CGPathMoveToPoint(path, nullptr, x, y);
+        CGPathAddLineToPoint(path, nullptr, x+0.001, y);
     }
 
     bool doRestore = false;
@@ -745,11 +745,11 @@ QCoreGraphicsPaintEngine::drawPolygon(const QPointF *points, int pointCount, Pol
         return;
 
     CGMutablePathRef path = CGPathCreateMutable();
-    CGPathMoveToPoint(path, 0, points[0].x(), points[0].y());
+    CGPathMoveToPoint(path, nullptr, points[0].x(), points[0].y());
     for (int x = 1; x < pointCount; ++x)
-        CGPathAddLineToPoint(path, 0, points[x].x(), points[x].y());
+        CGPathAddLineToPoint(path, nullptr, points[x].x(), points[x].y());
     if (mode != PolylineMode && points[0] != points[pointCount-1])
-        CGPathAddLineToPoint(path, 0, points[0].x(), points[0].y());
+        CGPathAddLineToPoint(path, nullptr, points[0].x(), points[0].y());
     uint op = QCoreGraphicsPaintEnginePrivate::CGStroke;
     if (mode != PolylineMode)
         op |= mode == OddEvenMode ? QCoreGraphicsPaintEnginePrivate::CGEOFill
@@ -770,8 +770,8 @@ QCoreGraphicsPaintEngine::drawLines(const QLineF *lines, int lineCount)
     CGMutablePathRef path = CGPathCreateMutable();
     for (int i = 0; i < lineCount; i++) {
         const QPointF start = lines[i].p1(), end = lines[i].p2();
-        CGPathMoveToPoint(path, 0, start.x(), start.y());
-        CGPathAddLineToPoint(path, 0, end.x(), end.y());
+        CGPathMoveToPoint(path, nullptr, start.x(), start.y());
+        CGPathAddLineToPoint(path, nullptr, end.x(), end.y());
     }
     d->drawPath(QCoreGraphicsPaintEnginePrivate::CGStroke, path);
     CGPathRelease(path);
@@ -870,7 +870,7 @@ QCoreGraphicsPaintEngine::drawTiledPixmap(const QRectF &r, const QPixmap &pixmap
     CGPatternRef pat = CGPatternCreate(qpattern, CGRectMake(0, 0, width, height),
             trans, width, height,
             kCGPatternTilingNoDistortion, true, &callbks);
-    CGColorSpaceRef cs = CGColorSpaceCreatePattern(0);
+    CGColorSpaceRef cs = CGColorSpaceCreatePattern(nullptr);
     CGContextSetFillColorSpace(d->hd, cs);
     CGFloat component = 1.0; //just one
     CGContextSetFillPattern(d->hd, pat, &component);
@@ -1198,9 +1198,9 @@ void QCoreGraphicsPaintEnginePrivate::setFillBrush(const QPointF &offset)
             Q_ASSERT(grad->spread() == QGradient::PadSpread);
 
             static const CGFloat domain[] = { 0.0f, +1.0f };
-            static const CGFunctionCallbacks callbacks = { 0, qt_mac_color_gradient_function, 0 };
+            static const CGFunctionCallbacks callbacks = { 0, qt_mac_color_gradient_function, nullptr };
             CGFunctionRef fill_func = CGFunctionCreate(reinterpret_cast<void *>(&current.brush),
-                    1, domain, 4, 0, &callbacks);
+                    1, domain, 4, nullptr, &callbacks);
 
             CGColorSpaceRef colorspace = CGColorSpaceCreateWithName(kCGColorSpaceSRGB)
             if (bs == Qt::LinearGradientPattern) {
@@ -1233,7 +1233,7 @@ void QCoreGraphicsPaintEnginePrivate::setFillBrush(const QPointF &offset)
         QMacPattern *qpattern = new QMacPattern;
         qpattern->pdev = pdev;
         CGFloat components[4] = { 1.0, 1.0, 1.0, 1.0 };
-        CGColorSpaceRef base_colorspace = 0;
+        CGColorSpaceRef base_colorspace = nullptr;
         if (bs == Qt::TexturePattern) {
             qpattern->data.pixmap = current.brush.texture();
             if (qpattern->data.pixmap.isQBitmap()) {
@@ -1291,7 +1291,7 @@ QCoreGraphicsPaintEnginePrivate::setClip(const QRegion *rgn)
         if (!sysClip.isEmpty())
             qt_mac_clip_cg(hd, sysClip, &orig_xform);
         if (rgn)
-            qt_mac_clip_cg(hd, *rgn, 0);
+            qt_mac_clip_cg(hd, *rgn, nullptr);
     }
 }
 
@@ -1404,7 +1404,7 @@ void QCoreGraphicsPaintEnginePrivate::drawPath(uchar ops, CGMutablePathRef path)
             t.transform = qt_mac_convert_transform_to_cg(current.transform);
             t.path = CGPathCreateMutable();
             CGPathApply(path, &t, qt_mac_cg_transform_path_apply); //transform the path
-            setTransform(0); //unset the context transform
+            setTransform(nullptr); //unset the context transform
             CGContextSetLineWidth(hd,  cosmeticPenSize);
             CGContextAddPath(hd, t.path);
             CGPathRelease(t.path);
diff --git a/src/plugins/platforms/cocoa/qpaintengine_mac_p.h b/src/plugins/platforms/cocoa/qpaintengine_mac_p.h
index c9519ac827..1416386745 100644
--- a/src/plugins/platforms/cocoa/qpaintengine_mac_p.h
+++ b/src/plugins/platforms/cocoa/qpaintengine_mac_p.h
@@ -135,7 +135,7 @@ class QCoreGraphicsPaintEnginePrivate : public QPaintEnginePrivate
     Q_DECLARE_PUBLIC(QCoreGraphicsPaintEngine)
 public:
     QCoreGraphicsPaintEnginePrivate()
-        : hd(0), shading(0), stackCount(0), complexXForm(false), disabledSmoothFonts(false)
+        : hd(nullptr), shading(nullptr), stackCount(0), complexXForm(false), disabledSmoothFonts(false)
     {
     }
 
@@ -164,8 +164,8 @@ public:
 
     //internal functions
     enum { CGStroke=0x01, CGEOFill=0x02, CGFill=0x04 };
-    void drawPath(uchar ops, CGMutablePathRef path = 0);
-    void setClip(const QRegion *rgn=0);
+    void drawPath(uchar ops, CGMutablePathRef path = nullptr);
+    void setClip(const QRegion *rgn = nullptr);
     void resetClip();
     void setFillBrush(const QPointF &origin=QPoint());
     void setStrokePen(const QPen &pen);
@@ -174,7 +174,7 @@ public:
     float penOffset();
     QPointF devicePixelSize(CGContextRef context);
     float adjustPenWidth(float penWidth);
-    inline void setTransform(const QTransform *matrix=0)
+    inline void setTransform(const QTransform *matrix = nullptr)
     {
         CGContextConcatCTM(hd, CGAffineTransformInvert(CGContextGetCTM(hd)));
         CGAffineTransform xform = orig_xform;
diff --git a/src/plugins/platforms/cocoa/qprintengine_mac.mm b/src/plugins/platforms/cocoa/qprintengine_mac.mm
index b3d48c1ec3..d34d7ddb0d 100644
--- a/src/plugins/platforms/cocoa/qprintengine_mac.mm
+++ b/src/plugins/platforms/cocoa/qprintengine_mac.mm
@@ -117,7 +117,7 @@ bool QMacPrintEngine::end()
     if (d->paintEngine->type() == QPaintEngine::CoreGraphics) {
         // We don't need the paint engine to call restoreGraphicsState()
         static_cast<QCoreGraphicsPaintEngine*>(d->paintEngine)->d_func()->stackCount = 0;
-        static_cast<QCoreGraphicsPaintEngine*>(d->paintEngine)->d_func()->hd = 0;
+        static_cast<QCoreGraphicsPaintEngine*>(d->paintEngine)->d_func()->hd = nullptr;
     }
     d->paintEngine->end();
     if (d->state != QPrinter::Idle)
@@ -271,7 +271,7 @@ void QMacPrintEnginePrivate::releaseSession()
     PMSessionEndPageNoDialog(session());
     PMSessionEndDocumentNoDialog(session());
     [printInfo release];
-    printInfo = 0;
+    printInfo = nil;
 }
 
 bool QMacPrintEnginePrivate::newPage_helper()
@@ -291,7 +291,7 @@ bool QMacPrintEnginePrivate::newPage_helper()
     while (cgEngine->d_func()->stackCount > 0)
         cgEngine->d_func()->restoreGraphicsState();
 
-    OSStatus status = PMSessionBeginPageNoDialog(session(), format(), 0);
+    OSStatus status = PMSessionBeginPageNoDialog(session(), format(), nullptr);
     if (status != noErr) {
         state = QPrinter::Error;
         return false;
@@ -318,7 +318,7 @@ bool QMacPrintEnginePrivate::newPage_helper()
     if (m_pageLayout.mode() != QPageLayout::FullPageMode)
         CGContextTranslateCTM(cgContext, page.x() - paper.x(), page.y() - paper.y());
     cgEngine->d_func()->orig_xform = CGContextGetCTM(cgContext);
-    cgEngine->d_func()->setClip(0);
+    cgEngine->d_func()->setClip(nullptr);
     cgEngine->state->dirtyFlags = QPaintEngine::DirtyFlag(QPaintEngine::AllDirty
                                                           & ~(QPaintEngine::DirtyClipEnabled
                                                               | QPaintEngine::DirtyClipRegion
@@ -340,7 +340,7 @@ void QMacPrintEnginePrivate::setPageSize(const QPageSize &pageSize)
 
     // Get the PMPaper and check it is valid
     PMPaper macPaper = m_printDevice->macPaper(usePageSize);
-    if (macPaper == 0) {
+    if (!macPaper) {
         qWarning() << "QMacPrintEngine: Invalid PMPaper returned for " << pageSize;
         return;
     }
diff --git a/src/plugins/platforms/cocoa/qprintengine_mac_p.h b/src/plugins/platforms/cocoa/qprintengine_mac_p.h
index 9514f3e691..3d94227ae4 100644
--- a/src/plugins/platforms/cocoa/qprintengine_mac_p.h
+++ b/src/plugins/platforms/cocoa/qprintengine_mac_p.h
@@ -134,7 +134,7 @@ public:
 
     QMacPrintEnginePrivate() : mode(QPrinter::ScreenResolution), state(QPrinter::Idle),
                                m_pageLayout(QPageLayout(QPageSize(QPageSize::A4), QPageLayout::Portrait, QMarginsF(0, 0, 0, 0))),
-                               printInfo(0), paintEngine(0), embedFonts(true) {}
+                               printInfo(nullptr), paintEngine(nullptr), embedFonts(true) {}
     ~QMacPrintEnginePrivate();
 
     void initialize();