help needed debugging a crash

[Jaroslaw Staniek]

On 16 April 2012 13:10, Dag <danders at get2net.dk> wrote:
> Mandag den 16. april 2012 12:52:39 Jaroslaw Staniek skrev:
>> On 16 April 2012 12:42, Dag <danders at get2net.dk> wrote:
>> > :Hi, I have a crash in plan on exit which I don't know how to squash.
>> >
>> > https://bugs.kde.org/show_bug.cgi?id=298075
>> >
>> > It happends sometimes (today: once in ~30 runs). I hoped it was a koffice
>> > issue because I had not seen it in calligra untill a few days ago.
>> >
>> > The crash is always in a dbus object in qobject.cpp:854 where it tries to
>> > access a declarative data object:
>> >
>> > 853 if (d->declarativeData)
>> > 854      QAbstractDeclarativeData::destroyed(d->declarativeData, this);
>> >
>> > When running gdb, I can see that d->declarativeData != 0, but the
>> > destroyed() function pointer == 0, hence crash.
>> >
>> > I cannot find any use of declaratives in dbus, but I might not have looked
>> > in the right place.
>> >
>> > The only theory I have is that there a bug somewhere that overwrites
>> > d->declarativeData.
>> >
>> > How to catch this?
>> > Anybody?
>>
>> Could Valgrind help?
> I have one crash when running in valgrind but afaics there is nothing obvious.
> I get some "invalid read size", "Use of uninitialised value" and "Conditional
> jump or move depends on uninitialised value" but it does not seem to originate
> in plan specific code.

Not even in calligra libs' code?

If an invalid pointer is passed to Qt API and accessed by Qt code
itself, it would be catched at Qt level indeed.
So this may happen.

-- 
regards / pozdrawiam, Jaroslaw Staniek
 http://www.linkedin.com/in/jstaniek
 Kexi & Calligra (kexi-project.org, identi.ca/kexi, calligra-suite.org)
 KDE Software Development Platform on MS Windows (windows.kde.org)