[PyQt] I'm seeing some strange behaviour whenever I quit my PyQt5 application

[Florian Bruhin]

Hey,

* Xavion <xavion.0 at gmail.com> [2016-09-06 15:56:20 +1000]:
> #0  0x00007ffff5cf3643 in ?? () from /usr/lib/libQt5Core.so.5
> #1  0x00007ffff5cf2d9b in QPropertyAnimation::updateState(QAbstractAnimation::State, QAbstractAnimation::State) () from /usr/lib/libQt5Core.so.5
> #2  0x00007ffff5ceb179 in QAbstractAnimation::stop() () from /usr/lib/libQt5Core.so.5
> #3  0x00007ffff5cf1a97 in QPropertyAnimation::~QPropertyAnimation() () from /usr/lib/libQt5Core.so.5
> #4  0x00007fffd1156343 in ?? () from /usr/lib/qt/plugins/styles/breeze.so

Indeed, this seems something caused by that style somehow. Python
destroys objects in an unpredictable order on shutdown, which can
cause those segfaults if people authoring the C++ code are not careful
enough - it's just quite tricky...

> #0  0x00007fffe98cbbe5 in QDBusMetaType::typeToSignature(int) () from /usr/lib/libQt5DBus.so.5
> #1  0x00007fffe98c2774 in qDBusParametersForMethod(QList<QByteArray> const&, QVector<int>&, QString&) () from /usr/lib/libQt5DBus.so.5
> #2  0x00007fffe98c2d4b in ?? () from /usr/lib/libQt5DBus.so.5
> #3  0x00007fffe988795e in ?? () from /usr/lib/libQt5DBus.so.5
> #4  0x00007fffe98881c5 in ?? () from /usr/lib/libQt5DBus.so.5
> #5  0x00007fffe9888c54 in ?? () from /usr/lib/libQt5DBus.so.5
> #6  0x00007fffe989afc3 in ?? () from /usr/lib/libQt5DBus.so.5

This smells like this bug: https://bugreports.qt.io/browse/QTBUG-52988

I still hope there'll be a fix in 5.6.2 and 5.7.1, but it's still
work-in-progress.

I have a patch which applies on 5.7.0 here:
http://paste.the-compiler.org/view/98e7c32d

I also maintain an unofficial Archlinux repository with binary
packages which have debugging symbols and this patch applied:

https://wiki.archlinux.org/index.php/Unofficial_user_repositories#qt-debug

Florian

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