QGuiApplication causes crash when there is no display available

A simple application like this:

#include <QGuiApplication>

int main(int argc, char** argv)
{
    QGuiApplication app(argc, argv);
    return app.exec();
}

causes crash when there is no display available:

$ DISPLAY="" ./gui_app
QXcbConnection: Could not connect to display
Aborted (core dumped)
$

Instead of unsetting DISPLAY one can run application from Xorg-less environment.
Any KDE application crashes in similar scenario.