Re: 64b Windows - crashes not detected

From:
"Alexander Grigoriev" <alegr@earthlink.net>
Newsgroups:
microsoft.public.vc.mfc
Date:
Thu, 20 Aug 2009 19:46:37 -0700
Message-ID:
<eHnLdmgIKHA.1380@TK2MSFTNGP02.phx.gbl>
Have you tried to single step through it in the debugger?

"phil oakleaf" <news@oakleafsoftware.co.uk> wrote in message
news:eJg8dUbIKHA.1684@TK2MSFTNGP04.phx.gbl...

David Lowndes wrote:

Phil,

Can you give us a simple self-contained console application that will
compile and illustrate the differences you're experiencing?

Dave

I am working with MFC so here is an example in that

Drop this into the main 'view' cpp file of a new MFC application (just
before 'OnDraw'

- on the 64bit machine this compiles and runs straight past the
NULL->testMe() part

- on the 32bit machine - Unhandled exception which is what I would expect

I'd be really interested to know if this happens on other machines -
becuase it definately happens on my two.

Many thanks
Phil

// couple of very simple classes

class MTest
{
public:
    float m_aVal;
    float m_bVal;
    MTest():m_aVal(0),m_bVal(0) {}

};

class RoomTest
{
public:
    MTest *m_mat;

    RoomTest():m_mat(NULL) {}

    virtual MTest *getMaterial() {return m_mat;}

    virtual void testMe()
    {
        MTest *tt=getMaterial();
        tt->m_bVal=45;
        tt->m_aVal=46;
    }
};

void CcrashTestView::OnDraw(CDC* /*pDC*/)
{
    CcrashTestDoc* pDoc = GetDocument();
    ASSERT_VALID(pDoc);
    if (!pDoc)
        return;

    // just create a real one
    RoomTest testRoom;

    // NULL pointer
    RoomTest *room=NULL;

    // call testMe on the NULL Pointer
    room->testMe();

    // TODO: add draw code for native data here
}

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