QGroupBox does not react to click to uncheck if setChecked is called with bad data

#include <QApplication>
#include <QDebug>
#include <QGroupBox>

int main(int argc, char *argv[])
{
    QApplication app(argc, argv);
    QGroupBox box;
    box.setCheckable(true);
    box.setTitle("Title");
    int i = 100;
    bool *a = reinterpret_cast<bool *>(&i);
    qDebug() << int(*a);
    box.setChecked(*a);
    box.show();
    return app.exec();
}