[vtkusers] QVTKWidget crashing randomly when maximized or closed.

[Clinton Stimpson]

What does the call stack look like?  Just knowing it crashes in malloc doesn't 
help any.  Maybe your app is corrupting the heap?

Clint

On Thursday 17 December 2009 12:07:49 pm ferr wrote:
> I will preface this with the fact that QVTKWidget is obviously intended for
> use with Qt, so it may be difficult to find an appropriate audience for
> this question, as it could fall on either a problem with Qt or VTK and
> would require knowledge of both frameworks.
>
> I have four QVTKWidget objects that are QMdiSubWindow inside of a QMdiArea.
> Sometimes, when I minimize one of them, and maximize another, the app
> crashes.  Also, the app will crash when I close a maximized QMdiSubWindow
> that contains a QVTKWidget.  Is there a known issue I should be aware of?
> Does QVTKWidget not work well with QMdiArea (or in certain situations with
> QMdiArea?)
>
> In this post at Qt-Interest I have provided further details including where
> it crashed to:
>
> http://lists.trolltech.com/pipermail/qt-interest/2009-December/016936.html
>
>
> I have four QMdiSubWindow widgets within a QMdiArea, each of which has its
> own QVTKWidget added to it.  Sometimes (it seems random, but often), after
> minimizing one of the sub windows, and clicking the maximize button on
> another sub window, I crash to line 105 of malloc.c
>
> *#ifdef _WIN64
>     return HeapAlloc(_crtheap, 0, size ? size : 1);
> #else  /* _WIN64 */
>     if (__active_heap == __SYSTEM_HEAP) {
>         return HeapAlloc(_crtheap, 0, size ? size : 1); //CRASHES TO THIS
> LINE
>     } else
>     if ( __active_heap == __V6_HEAP ) {
>         if (pvReturn = V6_HeapAlloc(size)) {
>             return pvReturn;
>         }
>     }*
>
>
> Also, when I maximize a subwindow, three buttons appear on the tool bar:
> Minimize / Restore / Close Window.  When I click Close Window it always
> crashes.to memcpy.asm at line 312:
>
> *        mov     [edi+ecx*4-16],eax ;U - put dword into destination*
>
>
> *
> *I do have code that handles resizing of the sub windows whenever the main
> window is resized, and I suspect it is possible that it could be linked to
> the crashing, but I can't see why, and debugging does not show it going
> into that area at any point around a crash.