QMainWindow::restoreState() should return false and don't do anything if the structure of the QMainWindow does not match the state.

It is not the case, QMainWindow::restoreState() returns true, and the QMainWindow is in a partially restored state. This can leads to crashes when the QMainWindow is modified after QMainWindow::restoreState().

Here is a test case for this issue:

#include <QtTest/QtTest>
#include <QtGui>

class Test : public QObject{
Q_OBJECT

private slots:
void restoreStateFailIfNotMatch() {
const QRect geometry(30, 40, 50, 60);
QByteArray state;

{ QMainWindow main; QDockWidget *dock = new QDockWidget("Dock1"); main.addDockWidget(Qt::LeftDockWidgetArea, dock); main.setGeometry(geometry); state = main.saveState(); } { QMainWindow main; main.setGeometry(geometry); bool ok = main.restoreState(state); QVERIFY(!ok); }

}
};

QTEST_MAIN(Test)
#include "test.moc"