Merge branch '4.7' of scm.dev.nokia.troll.no:qt/oslo-staging-1 into 4.7-integration

* '4.7' of scm.dev.nokia.troll.no:qt/oslo-staging-1:
  Don't add generic subdirs project twice.
  Remove debug, quiet warnings.
  Fix memory leaks and valgrind errors.
  QStroker: Fix erroneous SvgMiterJoin behavior for parallel lines
  Revert "Properly implement qobject_cast for const pointers."
  Bearer management: Fix compilation with namespace.
  fetch next token after class definition opening
  delay next token fetching when opening namespace
  don't let operator overloads confuse us
  don't try to show source when no locations are given
  Implement a private API for setting title widgets
  Fix the bug for QSettings on Windows, to store qint32/quint32, qint64/quint64 in Windows registry.
  fix CRLF
  Added private API to install an x11EventFilter
  NTLM code: Save domain in different variable
  Update the error handling of invalid hostnames in QUrl.
  Remove unsupported code from qobject.h for MSVC < .NET 2003
  Properly implement qobject_cast for const pointers.
  Revert "Doc: fixing page name bug caused by 07bbace404078dcfd82eff717daa97299b8ba52c changing qml elements page"

11 files changed, 151 insertions, 51 deletions

diff --git a/src/gui/kernel/qapplication_x11.cpp b/src/gui/kernel/qapplication_x11.cpp
index 7495f6d..e7b7ed8 100644
--- a/src/gui/kernel/qapplication_x11.cpp
+++ b/src/gui/kernel/qapplication_x11.cpp
@@ -400,11 +400,39 @@ QTabletDeviceDataList *qt_tablet_devices()
 extern bool qt_tabletChokeMouse;
 #endif
 
+typedef bool(*QX11FilterFunction)(XEvent *event);
+
+Q_GLOBAL_STATIC(QList<QX11FilterFunction>, x11Filters)
+
+Q_GUI_EXPORT void qt_installX11EventFilter(QX11FilterFunction func)
+{
+    Q_ASSERT(func);
+
+    if (QList<QX11FilterFunction> *list = x11Filters())
+        list->append(func);
+}
+
+Q_GUI_EXPORT void qt_removeX11EventFilter(QX11FilterFunction func)
+{
+    Q_ASSERT(func);
+
+    if (QList<QX11FilterFunction> *list = x11Filters())
+        list->removeOne(func);
+}
+
+
 static bool qt_x11EventFilter(XEvent* ev)
 {
     long unused;
     if (qApp->filterEvent(ev, &unused))
         return true;
+    if (const QList<QX11FilterFunction> *list = x11Filters()) {
+        for (QList<QX11FilterFunction>::const_iterator it = list->constBegin(); it != list->constEnd(); ++it) {
+            if ((*it)(ev))
+                return true;
+        }
+    }
+
     return qApp->x11EventFilter(ev);
 }
 
diff --git a/src/gui/kernel/qwidget_mac.mm b/src/gui/kernel/qwidget_mac.mm
index 1979c84..159c45d 100644
--- a/src/gui/kernel/qwidget_mac.mm
+++ b/src/gui/kernel/qwidget_mac.mm
@@ -2375,7 +2375,8 @@ void QWidgetPrivate::recreateMacWindow()
     HIViewRemoveFromSuperview(myView);
     determineWindowClass();
     createWindow_sys();
-    if (QMainWindowLayout *mwl = qobject_cast<QMainWindowLayout *>(q->layout())) {
+
+    if (QMainWindowLayout *mwl = qt_mainwindow_layout(qobject_cast<QMainWindow *>(q))) {
         mwl->updateHIToolBarStatus();
     }
 
@@ -2912,7 +2913,7 @@ void QWidgetPrivate::setParent_sys(QWidget *parent, Qt::WindowFlags f)
             // We do this down below for wasCreated, so avoid doing this twice
             // (only for performance, it gets called a lot anyway).
             if (!wasCreated) {
-                if (QMainWindowLayout *mwl = qobject_cast<QMainWindowLayout *>(q->layout())) {
+                if (QMainWindowLayout *mwl = qt_mainwindow_layout(qobject_cast<QMainWindow *>(q))) {
                     mwl->updateHIToolBarStatus();
                 }
             }
@@ -2937,7 +2938,7 @@ void QWidgetPrivate::setParent_sys(QWidget *parent, Qt::WindowFlags f)
         // If we were a unified window, We just transfered our toolbars out of the unified toolbar.
         // So redo the status one more time. It apparently is not an issue with Cocoa.
         if (q->isWindow()) {
-            if (QMainWindowLayout *mwl = qobject_cast<QMainWindowLayout *>(q->layout())) {
+            if (QMainWindowLayout *mwl = qt_mainwindow_layout(qobject_cast<QMainWindow *>(q))) {
                 mwl->updateHIToolBarStatus();
             }
         }
@@ -5138,7 +5139,7 @@ void QWidgetPrivate::macUpdateMetalAttribute()
             return;
         recreateMacWindow();
 #else
-        QMainWindowLayout *layout = qobject_cast<QMainWindowLayout *>(q->layout());
+        QMainWindowLayout *layout = qt_mainwindow_layout(qobject_cast<QMainWindow *>(q));
         if (q->testAttribute(Qt::WA_MacBrushedMetal)) {
             if (layout)
                 layout->updateHIToolBarStatus();
diff --git a/src/gui/painting/qstroker.cpp b/src/gui/painting/qstroker.cpp
index eabbd8a..9cff339 100644
--- a/src/gui/painting/qstroker.cpp
+++ b/src/gui/painting/qstroker.cpp
@@ -609,7 +609,7 @@ void QStroker::joinPoints(qfixed focal_x, qfixed focal_y, const QLineF &nextLine
             }
             QLineF miterLine(QPointF(qt_fixed_to_real(focal_x),
                                      qt_fixed_to_real(focal_y)), isect);
-            if (miterLine.length() > qt_fixed_to_real(m_strokeWidth * m_miterLimit) / 2) {
+            if (type == QLineF::NoIntersection || miterLine.length() > qt_fixed_to_real(m_strokeWidth * m_miterLimit) / 2) {
                 emitLineTo(qt_real_to_fixed(nextLine.x1()),
                            qt_real_to_fixed(nextLine.y1()));
             } else {
diff --git a/src/gui/widgets/qdockarealayout.cpp b/src/gui/widgets/qdockarealayout.cpp
index 171000b..b540e76 100644
--- a/src/gui/widgets/qdockarealayout.cpp
+++ b/src/gui/widgets/qdockarealayout.cpp
@@ -60,6 +60,9 @@
 
 QT_BEGIN_NAMESPACE
 
+// qmainwindow.cpp
+extern QMainWindowLayout *qt_mainwindow_layout(const QMainWindow *window);
+
 enum { StateFlagVisible = 1, StateFlagFloating = 2 };
 
 /******************************************************************************
@@ -1480,7 +1483,7 @@ QList<int> QDockAreaLayoutInfo::indexOf(QWidget *widget) const
 
 QMainWindowLayout *QDockAreaLayoutInfo::mainWindowLayout() const
 {
-    QMainWindowLayout *result = qobject_cast<QMainWindowLayout*>(mainWindow->layout());
+    QMainWindowLayout *result = qt_mainwindow_layout(mainWindow);
     Q_ASSERT(result != 0);
     return result;
 }
@@ -3070,8 +3073,7 @@ void QDockAreaLayout::splitDockWidget(QDockWidget *after,
 
 void QDockAreaLayout::apply(bool animate)
 {
-    QWidgetAnimator &widgetAnimator
-        = qobject_cast<QMainWindowLayout*>(mainWindow->layout())->widgetAnimator;
+    QWidgetAnimator &widgetAnimator = qt_mainwindow_layout(mainWindow)->widgetAnimator;
 
     for (int i = 0; i < QInternal::DockCount; ++i)
         docks[i].apply(animate);
@@ -3176,7 +3178,7 @@ void QDockAreaLayout::updateSeparatorWidgets() const
         if (j < separatorWidgets.size()) {
             sepWidget = separatorWidgets.at(j);
         } else {
-            sepWidget = qobject_cast<QMainWindowLayout*>(mainWindow->layout())->getSeparatorWidget();
+            sepWidget = qt_mainwindow_layout(mainWindow)->getSeparatorWidget();
             separatorWidgets.append(sepWidget);
         }
         j++;
diff --git a/src/gui/widgets/qdockwidget.cpp b/src/gui/widgets/qdockwidget.cpp
index 11f0a94..df9b171 100644
--- a/src/gui/widgets/qdockwidget.cpp
+++ b/src/gui/widgets/qdockwidget.cpp
@@ -68,6 +68,9 @@ QT_BEGIN_NAMESPACE
 
 extern QString qt_setWindowTitle_helperHelper(const QString&, const QWidget*); // qwidget.cpp
 
+// qmainwindow.cpp
+extern QMainWindowLayout *qt_mainwindow_layout(const QMainWindow *window);
+
 static inline bool hasFeature(const QDockWidgetPrivate *priv, QDockWidget::DockWidgetFeature feature)
 { return (priv->features & feature) == feature; }
 
@@ -690,7 +693,7 @@ void QDockWidgetPrivate::initDrag(const QPoint &pos, bool nca)
 
     QMainWindow *win = qobject_cast<QMainWindow*>(parent);
     Q_ASSERT(win != 0);
-    QMainWindowLayout *layout = qobject_cast<QMainWindowLayout*>(win->layout());
+    QMainWindowLayout *layout = qt_mainwindow_layout(win);
     Q_ASSERT(layout != 0);
     if (layout->pluggingWidget != 0) // the main window is animating a docking operation
         return;
@@ -711,8 +714,7 @@ void QDockWidgetPrivate::startDrag()
     if (state == 0 || state->dragging)
         return;
 
-    QMainWindowLayout *layout
-        = qobject_cast<QMainWindowLayout *>(q->parentWidget()->layout());
+    QMainWindowLayout *layout = qt_mainwindow_layout(qobject_cast<QMainWindow *>(q->parentWidget()));
     Q_ASSERT(layout != 0);
 
     state->widgetItem = layout->unplug(q);
@@ -739,8 +741,7 @@ void QDockWidgetPrivate::endDrag(bool abort)
     q->releaseMouse();
 
     if (state->dragging) {
-        QMainWindowLayout *mwLayout =
-            qobject_cast<QMainWindowLayout *>(q->parentWidget()->layout());
+        QMainWindowLayout *mwLayout = qt_mainwindow_layout(qobject_cast<QMainWindow *>(q->parentWidget()));
         Q_ASSERT(mwLayout != 0);
 
         if (abort || !mwLayout->plug(state->widgetItem)) {
@@ -780,8 +781,7 @@ bool QDockWidgetPrivate::isAnimating() const
     if (mainWin == 0)
         return false;
 
-    QMainWindowLayout *mainWinLayout
-        = qobject_cast<QMainWindowLayout*>(mainWin->layout());
+    QMainWindowLayout *mainWinLayout = qt_mainwindow_layout(mainWin);
     if (mainWinLayout == 0)
         return false;
 
@@ -847,9 +847,8 @@ bool QDockWidgetPrivate::mouseMoveEvent(QMouseEvent *event)
         return ret;
 
     QDockWidgetLayout *dwlayout
-        = qobject_cast<QDockWidgetLayout*>(layout);
-    QMainWindowLayout *mwlayout
-        = qobject_cast<QMainWindowLayout*>(q->parentWidget()->layout());
+        = qobject_cast<QDockWidgetLayout *>(layout);
+    QMainWindowLayout *mwlayout = qt_mainwindow_layout(qobject_cast<QMainWindow *>(q->parentWidget()));
     if (!dwlayout->nativeWindowDeco()) {
         if (!state->dragging
             && mwlayout->pluggingWidget == 0
@@ -943,8 +942,7 @@ void QDockWidgetPrivate::nonClientAreaMouseEvent(QMouseEvent *event)
             }
 #ifdef Q_OS_MAC
             else { // workaround for lack of mouse-grab on Mac
-                QMainWindowLayout *layout
-                    = qobject_cast<QMainWindowLayout *>(q->parentWidget()->layout());
+                QMainWindowLayout *layout = qt_mainwindow_layout(qobject_cast<QMainWindow *>(q->parentWidget()));
                 Q_ASSERT(layout != 0);
 
                 q->move(event->globalPos() - state->pressPos);
@@ -980,8 +978,7 @@ void QDockWidgetPrivate::moveEvent(QMoveEvent *event)
     if (state->ctrlDrag)
         return;
 
-    QMainWindowLayout *layout
-        = qobject_cast<QMainWindowLayout *>(q->parentWidget()->layout());
+    QMainWindowLayout *layout = qt_mainwindow_layout(qobject_cast<QMainWindow *>(q->parentWidget()));
     Q_ASSERT(layout != 0);
 
     QPoint globalMousePos = event->pos() + state->pressPos;
@@ -1009,7 +1006,7 @@ void QDockWidgetPrivate::setWindowState(bool floating, bool unplug, const QRect
     Q_Q(QDockWidget);
 
     if (!floating && parent) {
-        QMainWindowLayout *mwlayout = qobject_cast<QMainWindowLayout *>(q->parentWidget()->layout());
+        QMainWindowLayout *mwlayout = qt_mainwindow_layout(qobject_cast<QMainWindow *>(q->parentWidget()));
         if (mwlayout && mwlayout->dockWidgetArea(q) == Qt::NoDockWidgetArea)
             return; // this dockwidget can't be redocked
     }
@@ -1055,7 +1052,7 @@ void QDockWidgetPrivate::setWindowState(bool floating, bool unplug, const QRect
     if (floating != wasFloating) {
         emit q->topLevelChanged(floating);
         if (!floating && parent) {
-            QMainWindowLayout *mwlayout = qobject_cast<QMainWindowLayout *>(q->parentWidget()->layout());
+            QMainWindowLayout *mwlayout = qt_mainwindow_layout(qobject_cast<QMainWindow *>(q->parentWidget()));
             if (mwlayout)
                 emit q->dockLocationChanged(mwlayout->dockWidgetArea(q));
         }
@@ -1326,10 +1323,10 @@ void QDockWidget::changeEvent(QEvent *event)
 #ifndef QT_NO_TABBAR
         {
             QMainWindow *win = qobject_cast<QMainWindow*>(parentWidget());
-            if (QMainWindowLayout *winLayout =
-                (win ? qobject_cast<QMainWindowLayout*>(win->layout()) : 0))
+            if (QMainWindowLayout *winLayout = qt_mainwindow_layout(win)) {
                 if (QDockAreaLayoutInfo *info = winLayout->layoutState.dockAreaLayout.info(this))
                     info->updateTabBar();
+            }
         }
 #endif // QT_NO_TABBAR
         break;
@@ -1382,9 +1379,7 @@ bool QDockWidget::event(QEvent *event)
     Q_D(QDockWidget);
 
     QMainWindow *win = qobject_cast<QMainWindow*>(parentWidget());
-    QMainWindowLayout *layout = 0;
-    if (win != 0)
-        layout = qobject_cast<QMainWindowLayout*>(win->layout());
+    QMainWindowLayout *layout = qt_mainwindow_layout(win);
 
     switch (event->type()) {
 #ifndef QT_NO_ACTION
diff --git a/src/gui/widgets/qmainwindow.cpp b/src/gui/widgets/qmainwindow.cpp
index 44483ea..1183be6 100644
--- a/src/gui/widgets/qmainwindow.cpp
+++ b/src/gui/widgets/qmainwindow.cpp
@@ -39,6 +39,8 @@
 **
 ****************************************************************************/
 
+//#define QT_EXPERIMENTAL_CLIENT_DECORATIONS
+
 #include "qmainwindow.h"
 #include "qmainwindowlayout_p.h"
 
@@ -99,12 +101,70 @@ public:
     uint hasOldCursor : 1;
     uint cursorAdjusted : 1;
 #endif
+
+    static inline QMainWindowLayout *mainWindowLayout(const QMainWindow *mainWindow)
+    {
+        return mainWindow ? mainWindow->d_func()->layout : static_cast<QMainWindowLayout *>(0);
+    }
 };
 
+QMainWindowLayout *qt_mainwindow_layout(const QMainWindow *mainWindow)
+{
+    return QMainWindowPrivate::mainWindowLayout(mainWindow);
+}
+
+#ifdef QT_EXPERIMENTAL_CLIENT_DECORATIONS
+Q_GUI_EXPORT void qt_setMainWindowTitleWidget(QMainWindow *mainWindow, Qt::DockWidgetArea area, QWidget *widget)
+{
+    QGridLayout *topLayout = qobject_cast<QGridLayout *>(mainWindow->layout());
+    Q_ASSERT(topLayout);
+
+    int row = 0;
+    int column = 0;
+
+    switch (area) {
+    case Qt::LeftDockWidgetArea:
+        row = 1;
+        column = 0;
+        break;
+    case Qt::TopDockWidgetArea:
+        row = 0;
+        column = 1;
+        break;
+    case Qt::BottomDockWidgetArea:
+        row = 2;
+        column = 1;
+        break;
+    case Qt::RightDockWidgetArea:
+        row = 1;
+        column = 2;
+        break;
+    default:
+        Q_ASSERT_X(false, "qt_setMainWindowTitleWidget", "Unknown area");
+        return;
+    }
+
+    if (QLayoutItem *oldItem = topLayout->itemAtPosition(row, column))
+        delete oldItem->widget();
+    topLayout->addWidget(widget, row, column);
+}
+#endif
+
 void QMainWindowPrivate::init()
 {
     Q_Q(QMainWindow);
-    layout = new QMainWindowLayout(q);
+
+#ifdef QT_EXPERIMENTAL_CLIENT_DECORATIONS
+    QGridLayout *topLayout = new QGridLayout(q);
+    topLayout->setContentsMargins(0, 0, 0, 0);
+
+    layout = new QMainWindowLayout(q, topLayout);
+
+    topLayout->addItem(layout, 1, 1);
+#else
+    layout = new QMainWindowLayout(q, 0);
+#endif
+
     const int metric = q->style()->pixelMetric(QStyle::PM_ToolBarIconSize, 0, q);
     iconSize = QSize(metric, metric);
     q->setAttribute(Qt::WA_Hover);
@@ -461,10 +521,11 @@ QMenuBar *QMainWindow::menuBar() const
 */
 void QMainWindow::setMenuBar(QMenuBar *menuBar)
 {
-    Q_D(QMainWindow);
-    if (d->layout->menuBar() && d->layout->menuBar() != menuBar) {
+    QLayout *topLayout = layout();
+
+    if (topLayout->menuBar() && topLayout->menuBar() != menuBar) {
         // Reparent corner widgets before we delete the old menu bar.
-        QMenuBar *oldMenuBar = qobject_cast<QMenuBar *>(d->layout->menuBar());
+        QMenuBar *oldMenuBar = qobject_cast<QMenuBar *>(topLayout->menuBar());
         if (menuBar) {
             // TopLeftCorner widget.
             QWidget *cornerWidget = oldMenuBar->cornerWidget(Qt::TopLeftCorner);
@@ -478,7 +539,7 @@ void QMainWindow::setMenuBar(QMenuBar *menuBar)
         oldMenuBar->hide();
         oldMenuBar->deleteLater();
     }
-    d->layout->setMenuBar(menuBar);
+    topLayout->setMenuBar(menuBar);
 }
 
 /*!
diff --git a/src/gui/widgets/qmainwindowlayout.cpp b/src/gui/widgets/qmainwindowlayout.cpp
index 62ee398..4dd5208 100644
--- a/src/gui/widgets/qmainwindowlayout.cpp
+++ b/src/gui/widgets/qmainwindowlayout.cpp
@@ -160,7 +160,7 @@ static void dumpLayout(QTextStream &qout, const QDockAreaLayout &layout, QString
 
 void qt_dumpLayout(QTextStream &qout, QMainWindow *window)
 {
-    QMainWindowLayout *layout = qobject_cast<QMainWindowLayout*>(window->layout());
+    QMainWindowLayout *layout = qt_mainwindow_layout(window);
     dumpLayout(qout, layout->layoutState.dockAreaLayout, QString());
 }
 
@@ -235,7 +235,7 @@ void QMainWindowLayoutState::apply(bool animated)
     dockAreaLayout.apply(animated);
 #else
     if (centralWidgetItem != 0) {
-        QMainWindowLayout *layout = qobject_cast<QMainWindowLayout*>(mainWindow->layout());
+        QMainWindowLayout *layout = qt_mainwindow_layout(mainWindow);
         Q_ASSERT(layout != 0);
         layout->widgetAnimator.animate(centralWidgetItem->widget(), centralWidgetRect, animated);
     }
@@ -1674,8 +1674,8 @@ void QMainWindowLayout::restore(bool keepSavedState)
     updateGapIndicator();
 }
 
-QMainWindowLayout::QMainWindowLayout(QMainWindow *mainwindow)
-    : QLayout(mainwindow)
+QMainWindowLayout::QMainWindowLayout(QMainWindow *mainwindow, QLayout *parentLayout)
+    : QLayout(parentLayout ? static_cast<QWidget *>(0) : mainwindow)
     , layoutState(mainwindow)
     , savedState(mainwindow)
     , dockOptions(QMainWindow::AnimatedDocks | QMainWindow::AllowTabbedDocks)
@@ -1698,6 +1698,9 @@ QMainWindowLayout::QMainWindowLayout(QMainWindow *mainwindow)
     , blockVisiblityCheck(false)
 #endif
 {
+    if (parentLayout)
+        setParent(parentLayout);
+
 #ifndef QT_NO_DOCKWIDGET
 #ifndef QT_NO_TABBAR
     sep = mainwindow->style()->pixelMetric(QStyle::PM_DockWidgetSeparatorExtent, 0, mainwindow);
diff --git a/src/gui/widgets/qmainwindowlayout_p.h b/src/gui/widgets/qmainwindowlayout_p.h
index 955693d..e1b981c 100644
--- a/src/gui/widgets/qmainwindowlayout_p.h
+++ b/src/gui/widgets/qmainwindowlayout_p.h
@@ -159,7 +159,7 @@ class Q_AUTOTEST_EXPORT QMainWindowLayout : public QLayout
 public:
     QMainWindowLayoutState layoutState, savedState;
 
-    explicit QMainWindowLayout(QMainWindow *mainwindow);
+    QMainWindowLayout(QMainWindow *mainwindow, QLayout *parentLayout);
     ~QMainWindowLayout();
 
     QMainWindow::DockOptions dockOptions;
diff --git a/src/gui/widgets/qtoolbar.cpp b/src/gui/widgets/qtoolbar.cpp
index 7ed27ea..316bb44 100644
--- a/src/gui/widgets/qtoolbar.cpp
+++ b/src/gui/widgets/qtoolbar.cpp
@@ -82,6 +82,9 @@ static void qt_mac_updateToolBarButtonHint(QWidget *parentWidget)
 }
 #endif
 
+// qmainwindow.cpp
+extern QMainWindowLayout *qt_mainwindow_layout(const QMainWindow *window);
+
 /******************************************************************************
 ** QToolBarPrivate
 */
@@ -197,7 +200,7 @@ void QToolBarPrivate::initDrag(const QPoint &pos)
 
     QMainWindow *win = qobject_cast<QMainWindow*>(parent);
     Q_ASSERT(win != 0);
-    QMainWindowLayout *layout = qobject_cast<QMainWindowLayout*>(win->layout());
+    QMainWindowLayout *layout = qt_mainwindow_layout(win);
     Q_ASSERT(layout != 0);
     if (layout->pluggingWidget != 0) // the main window is animating a docking operation
         return;
@@ -223,7 +226,7 @@ void QToolBarPrivate::startDrag(bool moving)
 
     QMainWindow *win = qobject_cast<QMainWindow*>(parent);
     Q_ASSERT(win != 0);
-    QMainWindowLayout *layout = qobject_cast<QMainWindowLayout*>(win->layout());
+    QMainWindowLayout *layout = qt_mainwindow_layout(win);
     Q_ASSERT(layout != 0);
 
     if (!moving) {
@@ -247,8 +250,7 @@ void QToolBarPrivate::endDrag()
     q->releaseMouse();
 
     if (state->dragging) {
-        QMainWindowLayout *layout =
-            qobject_cast<QMainWindowLayout *>(q->parentWidget()->layout());
+        QMainWindowLayout *layout = qt_mainwindow_layout(qobject_cast<QMainWindow *>(q->parentWidget()));
         Q_ASSERT(layout != 0);
 
         if (!layout->plug(state->widgetItem)) {
@@ -340,7 +342,7 @@ bool QToolBarPrivate::mouseMoveEvent(QMouseEvent *event)
     if (win == 0)
         return true;
 
-    QMainWindowLayout *layout = qobject_cast<QMainWindowLayout*>(win->layout());
+    QMainWindowLayout *layout = qt_mainwindow_layout(win);
     Q_ASSERT(layout != 0);
 
     if (layout->pluggingWidget == 0
@@ -588,7 +590,7 @@ QToolBar::~QToolBar()
     QMainWindow *mainwindow = qobject_cast<QMainWindow *>(parentWidget());
     if (mainwindow) {
 #ifdef Q_WS_MAC
-        QMainWindowLayout *mainwin_layout = qobject_cast<QMainWindowLayout *>(mainwindow->layout());
+        QMainWindowLayout *mainwin_layout = qt_mainwindow_layout(mainwindow);
         if (mainwin_layout && mainwin_layout->layoutState.toolBarAreaLayout.isEmpty()
                 && mainwindow->testAttribute(Qt::WA_WState_Created))
             macWindowToolbarShow(mainwindow, false);
@@ -1135,7 +1137,7 @@ bool QToolBar::event(QEvent *event)
         if (toolbarInUnifiedToolBar(this)) {
              // I can static_cast because I did the qobject_cast in the if above, therefore
             // we must have a QMainWindowLayout here.
-            QMainWindowLayout *mwLayout = static_cast<QMainWindowLayout *>(parentWidget()->layout());
+            QMainWindowLayout *mwLayout = qt_mainwindow_layout(qobject_cast<QMainWindow *>(parentWidget()));
             mwLayout->fixSizeInUnifiedToolbar(this);
             mwLayout->syncUnifiedToolbarVisibility();
         }
@@ -1289,6 +1291,8 @@ QWidget *QToolBar::widgetForAction(QAction *action) const
     return d->layout->itemAt(index)->widget();
 }
 
+extern QMainWindowLayout *qt_mainwindow_layout(const QMainWindow *window);
+
 /*!
     \internal
 */
@@ -1315,7 +1319,7 @@ void QToolBar::initStyleOption(QStyleOptionToolBar *option) const
     if (!mainWindow)
         return;
 
-    QMainWindowLayout *layout = qobject_cast<QMainWindowLayout *>(mainWindow->layout());
+    QMainWindowLayout *layout = qt_mainwindow_layout(mainWindow);
     Q_ASSERT_X(layout != 0, "QToolBar::initStyleOption()",
                "QMainWindow->layout() != QMainWindowLayout");
 
diff --git a/src/gui/widgets/qtoolbararealayout.cpp b/src/gui/widgets/qtoolbararealayout.cpp
index 8327af5..b312751 100644
--- a/src/gui/widgets/qtoolbararealayout.cpp
+++ b/src/gui/widgets/qtoolbararealayout.cpp
@@ -59,6 +59,9 @@
 
 QT_BEGIN_NAMESPACE
 
+// qmainwindow.cpp
+extern QMainWindowLayout *qt_mainwindow_layout(const QMainWindow *mainWindow);
+
 QSize QToolBarAreaLayoutItem::minimumSize() const
 {
     if (skip())
@@ -872,7 +875,7 @@ void QToolBarAreaLayout::insertItem(QToolBar *before, QLayoutItem *item)
 
 void QToolBarAreaLayout::apply(bool animate)
 {
-    QMainWindowLayout *layout = qobject_cast<QMainWindowLayout*>(mainWindow->layout());
+    QMainWindowLayout *layout = qt_mainwindow_layout(mainWindow);
     Q_ASSERT(layout != 0);
 
     Qt::LayoutDirection dir = mainWindow->layoutDirection();
diff --git a/src/gui/widgets/qtoolbarlayout.cpp b/src/gui/widgets/qtoolbarlayout.cpp
index f87510f..59b027e 100644
--- a/src/gui/widgets/qtoolbarlayout.cpp
+++ b/src/gui/widgets/qtoolbarlayout.cpp
@@ -57,6 +57,9 @@
 
 QT_BEGIN_NAMESPACE
 
+// qmainwindow.cpp
+extern QMainWindowLayout *qt_mainwindow_layout(const QMainWindow *window);
+
 /******************************************************************************
 ** QToolBarItem
 */
@@ -404,7 +407,7 @@ void QToolBarLayout::setGeometry(const QRect &rect)
     if (QMainWindow *win = qobject_cast<QMainWindow*>(tb->parentWidget())) {
         Qt::ToolBarArea area = win->toolBarArea(tb);
         if (win->unifiedTitleAndToolBarOnMac() && area == Qt::TopToolBarArea) {
-            static_cast<QMainWindowLayout *>(win->layout())->fixSizeInUnifiedToolbar(tb);
+            qt_mainwindow_layout(win)->fixSizeInUnifiedToolbar(tb);
         }
     }
 #  endif
@@ -659,7 +662,7 @@ void QToolBarLayout::setExpanded(bool exp)
 #else
         animating = !tb->isWindow() && win->isAnimated();
 #endif
-        QMainWindowLayout *layout = qobject_cast<QMainWindowLayout*>(win->layout());
+        QMainWindowLayout *layout = qt_mainwindow_layout(win);
         if (expanded) {
             tb->raise();
         } else {