Re: CWinThread, CFrameWnd and memory leak???

From:

ole.tetzschner@gmail.com

Newsgroups:

microsoft.public.vc.mfc

Date:

Sat, 9 Feb 2008 08:37:49 -0800 (PST)

Message-ID:

<205d9ae8-4e3e-4eb6-95d7-6265933c60c6@l16g2000hsh.googlegroups.com>

On Feb 9, 5:25 pm, Joseph M. Newcomer <newco...@flounder.com> wrote:

If you are leaking from a "CFrameWnd" object, it is unlikely that it is a =

CWinThread

object. Could you show the message?

Normally, when you create a CWinThread-derived thread, the m_bAutoDelete f=

lag is TRUE, and

therefore the CWinThread object will be automatically deleted when the thr=

ead terminates.

This would be verified by the fact that an attempt to delete it a second t=

ime results in a

catastrophic failure. So it is unlikely that it is your CmyUIthread obj=

ect. But make

sure the destructors for that object delete anything it had allocated; for=

example, if it

had a CWhatever* pointer in it, its destructor had better delete that obje=

ct (unless

someone else has responsibility for deleting it)
=

joe

On Sat, 9 Feb 2008 07:21:14 -0800 (PST), ole.tetzsch...@gmail.com wrote:

Hi

I guess it's just me being stupid, but I been googling and trying for
hours now and can't solve this problem myself.

The Problem is I have created a class (CmyUIthread) derived from
CWinThread, but when my test-app exit the compiler reports a memory
leak from a CFrameWnd object.

My test-app is just a dialog-app with 2 buttons. The first button just
create and starts the ui-thread:

   m_p_thread = new CmyUIthread;
   m_p_thread->CreateThread();

And the tread starts perfect :)

The second button stops the thread:

   m_p_thread->PostThreadMessage( WM_QUIT,0,0);

And the thread stops :)

But when i quit my dlg-test-app the compiler reports the memory
leak???

I tried adding a third button that:

   delete m_p_thread;

but this results in access violations.

CmyUIthread looks like this:

CmyUIthread::CmyUIthread()
{
}

CmyUIthread::~CmyUIthread()
{
}

BOOL CmyUIthread::InitInstance()
{
   // TODO: perform and per-thread initialization here
   CFrameWnd *wnd = new CFrameWnd;
   wnd->Create( NULL, "myUIthread Window");
   wnd->ShowWindow( SW_SHOW);
   wnd->UpdateWindow();
   m_pMainWnd = wnd;

   return TRUE;
}

int CmyUIthread::ExitInstance()
{
   // TODO: perform any per-thread cleanup here
   return CWinThread::ExitInstance();
}

BEGIN_MESSAGE_MAP(CmyUIthread, CWinThread)
END_MESSAGE_MAP()

What is wrong??? do I miss some cleanup???

With kind regards.. Ole

Joseph M. Newcomer [MVP]
email: newco...@flounder.com
Web:http://www.flounder.com
MVP Tips:http://www.flounder.com/mvp_tips.htm

Hi Joseph

Thanks for you quick reply :)

The messages is:

The thread 'Win32 Thread' (0x6c0) has exited with code 0 (0x0).
Detected memory leaks!
Dumping objects ->
f:\sp\vctools\vc7libs\ship\atlmfc\src\mfc\strcore.cpp(141) : {105}
normal block at 0x003A74D0, 34 bytes long.
Data: <, ?x > 2C 08 3F 78 11 00 00 00 11 00 00 00 01 00 00
00
{104} client block at 0x003A98B0, subtype c0, 212 bytes long.
a CFrameWnd object at $003A98B0, 212 bytes long
Object dump complete.
The program '[3232] myThreadTest.exe: Native' has exited with code 2
(0x2).

This is a fresh wizard-generated dialog project where I add the
CWinThread derived class also by the wizard. The only code I added to
CmyUIthread is in the InitInstance... and changed the destructor and
constructor to public (so I could use the "new" to generate the object
in my dialog-test-app).

What is it I need to clean-up ???

With kind regards... Ole