Crash in Qt Serial Port when using USB-serial adapter

There seems to be a heap corruption after calling QSerialPortInfo::availablePorts(), because deleting the resulting list causes
------
Debug Assertion Failed!
File: f:\dd\vctools\crt\crtw32\misc\dbgdel.cpp
Line: 52
Expression: _BLOCK_TYPE_IS_VALID(pHead->nBlockUse)
------
This happens only with an USB-serial adapter. If you haven't plugged in any adapters the application works correctly.
The test application is straightforward:

#include <QList>
#include <QtSerialPort/QSerialPortInfo>

void infoTest()
{
    QList<QSerialPortInfo> ports = QSerialPortInfo::availablePorts();
}

void main(int, char)
{
    infoTest();
}

The crash happens when exiting the infoTest() function i.e. when deleting the ports list.