debugging segfaults in pythen PyQt (QWebview)

[Hans-Peter Jansen]

On Thursday 03 March 2011, 10:40:20 Gelonida wrote:
> Hi,
>
> I have a QWebview application, which segfaults rather often,
> but not all the time.
>
> I assume it is some kind of race condition when loading a certain web
> page with quite some built in AJax.
>
[...]
>
> The application crashes under Windows and under Linux.
>
[...]
>
> Is there any way to obtain the related  backtrace of the python
> script?
>
[...]

Before you're able to track your issue back into python, you will have 
to prepare a debuggable environment. In Linux, there's usually a way to 
install the debug symbols of the packages in question. In your case, 
you might want to install debug symbols (and probably debug sources) of 
(package names differ from distro to distro, of course):
 - libqt4 
 - libwebkit
 - python
 - python-sip
 - python-qt4

Next, you run your script:

	gdb python -ex "set args script.py" -ex run

Now, get it to crash and type bt at the gdb prompt.

Paste all info before and after bt into a mail, and send it to 
pyqt at riverbankcomputing.com ML (at least). That's the proper place for 
such issues, and chances are high, that you will get further help over 
there. It's a good idea to subscribe that (low traffic) list, even if 
you hack PyQt only occasionly. It has an astonishing high S/R ratio, 
btw (compared to the 50 other lists, that I'm subscribed at).

Don't forget to specify your environment as detailed as possible (arch, 
package versions, etc..). A perfect report includes a minimum runnable 
example script.

Good luck,
Pete