[PyQt] [PyKDE] KCrash, sometimes even glibc
phil at riverbankcomputing.co.uk
Mon Aug 27 10:31:04 BST 2007
On Monday 27 August 2007, Henrik Pauli wrote:
> Hi all,
> Some of you might know that I'm writing a livejournal client for KDE (and
> now Qt4 too) called ljKlient...
> I've been trying to find the culprit for this, but I absolutely have no
> idea. The crashes don't tell me anything useful, and I've combed through
> the source files that I find relevant to the crash (for example I know that
> it doesn't tend to crash if I don't open the friendlistwindow, but that too
> isn't 100% the case!), and I found nothing that's nasty.
> And the thing only, ever, crashes on exit. Never anytime else. There are
> cases when it only crashes with py251 but doesn't with py24. Crazy stuff.
> Sometimes it's just KCrash getting triggered, sometimes (only with py25)
> even glibc panics about some double-linked list having gotten corrupted.
> MALLOC_CHECK_=2 does not terminate the application either.
> Ask me any details, I'll try to tell as much as I know :)
Crashes on exit have two causes...
- PyQt bugs related to object ownership
- C++ objects being deleted in the wrong order (because Python objects are
being garbage collected in a fairly random order).
To debug these...
- Always use current SIP and PyQt snapshots.
- Strip your application down to the bare minimum while still demonstrating
the problem - I would expect no more than 100 lines.
- Post the example to the list as an attachment.
More information about the PyQt