When setting setUnifiedTitleAndToolBarOnMac to true and going to fullscreen and back to normal view, the application crashes, see stack trace in attached text file.

How to reproduce

• On a Mac, Compile the attached example code
• Go fullscreen (CMD + F or toggle action in toolbar/menu)
• Go normal view (again same action)
• crash

Example code

MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);    	
    setUnifiedTitleAndToolBarOnMac(true);
}

MainWindow::~MainWindow()
{
    delete ui;
}

void MainWindow::on_fullscreenAction_triggered()
{
    if (!isFullScreen()) {
        // setUnifiedTitleAndToolBarOnMac(false);
        showFullScreen();
    } else {
        // setUnifiedTitleAndToolBarOnMac(true);
        showNormal();
    }
}

Workaround

When following the advice on http://doc.trolltech.com/4.7/qmainwindow.html#unifiedTitleAndToolBarOnMac-prop : "However, a good practice would be that turning off the unified toolbar before you call showFullScreen() and restoring it after you call showNormal()." then there is no crash. See commented out code.

Example code attached.