I have a QObject class which I launch in a QThread. Everything seems to be working fine until I try to QThread::quit() the thread, at which point my application crashes with an:
ASSERT failure in QMutexLocker: "QMutex pointer is misaligned", file thread\qmutex.h, line 196
Whilst I have been developing code in Visual Studio for many years, I'm quite new to QT (which I'm loving BTW!). To be honest, I'm not sure how to quit the thread and close my QObject class correctly. My code is as follows:

Header of my QObject Class:

#ifndef UPNPDISCOVERTHREAD_H
#define UPNPDISCOVERTHREAD_H

#include "../upnp/avcontrol.hpp"
#include "../upnp/actioninfo.hpp"

#include <QObject>
#include <QThread>
#include <QDebug>

namespace upnp
{
 class CControlPoint;
};

USING_UPNP_NAMESPACE

class CUpnpDiscoverThread : public QObject
{
    Q_OBJECT
public:
    explicit CUpnpDiscoverThread(int numSwitches, QObject *parent = nullptr);
    ~CUpnpDiscoverThread();
    void start(QThread &thread);

signals:
    /*! Emitted when a all switches are found. */
    void scanComplete(QVarLengthArray<struct WemoSwitch *> *ws);

protected slots:
    void newDevice (QString const & uuid);
    void upnpError (int errorCode, QString const & errorString);
    void networkError (QString const & deviceUUID, QNetworkReply::NetworkError errorCode, QString const & errorString);
    void isScanFinished();

public slots:
    void startDiscovery();
    void quit();

private:
    CControlPoint* m_cp = nullptr; //!< It is the CControlPoint.
    QList<CControlPoint::TArgValue> m_args;
    int GetSignalStrength( struct WemoSwitch *ws );
    int m_switchCount; // Because I don't know when the network scan is complete, I count the number of switches discovered every X secs, if it hasn't changed in Y secs, then I assume the scan is complete
    int m_retrySwitchCount; // The number of times to retry the switch count before timing out.
    int m_numSwitches; // The number of scanned switches expected to be found
    QVarLengthArray<struct WemoSwitch *> m_wemoSwitches;
};

#endif // UPNPDISCOVERTHREAD_H

QObject CPP (part of):

#include "upnpdiscoverthread.h"
#include "globals.h"

#include <QDir>
#include <QSettings>
#include <QtXml>
#include <QMessageBox>
#include <QDebug>

CUpnpDiscoverThread::CUpnpDiscoverThread(int numSwitches, QObject *parent) : m_numSwitches( numSwitches), QObject(parent)
{
}

CUpnpDiscoverThread::~CUpnpDiscoverThread()
{
    if ( m_cp )
    {
        m_cp->close();

        delete m_cp;
    }
}

void CUpnpDiscoverThread::start(QThread &thread)
{
    connect( &thread, SIGNAL(started()), this, SLOT(startDiscovery()));
    connect( &thread, SIGNAL(finished()), this, SLOT(quit()));
}

void CUpnpDiscoverThread::startDiscovery()
{
    qDebug() << "Starting discovery";

   ...
}

void CUpnpDiscoverThread::quit()
{
    quit();
}

void CUpnpDiscoverThread::isScanFinished()
{
      emit scanComplete( &m_wemoSwitches);
}

Main window construction and execution of thread:

CUpnpDiscoverThread *m_discover = new CUpnpDiscoverThread( count );

QThread *m_discoverThread = new QThread( this );

m_discover->start( *m_discoverThread );

m_discover->moveToThread( m_discoverThread );

m_discoverThread->start();

connect( m_discover, &CUpnpDiscoverThread::scanComplete, this, &MainWindow::scanComplete );

Main window termination of thread (called in the scanComplete SLOT):

m_discoverThread->quit();

delete m_discoverThread;

delete m_discover;

• Could someone please shed some light on what I am doing wrong, and how to correctly terminate my thread and class?

• I assumed that the QThread::quit() would send a finished SIGNAL to my QObject?

• I assume it is up to me to delete the QThread and QObject?

Thanks heaps in advance.

Steve Q. :-)