QProcess/Win crash on empty program and args

QProcess will crash on Windows when passing an empty program and an empty argument list.

#include <QCoreApplication>
#include <QProcess>

int main(int argc, char *argv[])
{
    QCoreApplication a(argc, argv);
    QProcess p;
    p.start(QString(), QStringList());
    return a.exec();
}

The reason is that the QString args whose buffer is passed to CreateProcess is a null QString in this case.
The QString args points to readonly memory. However, CreateProcess must be able to modify the argument buffer.

Note that the following code is not affected:

    QProcess p;
    p.start(QString());

In this case QProcess::start() bails out if the argument is empty.