[Python-modules-team] Bug#962846: Bug#962811: calibre: ebook-viewer crash on start

[Dmitry Shachnev]

Hi Davide!

On Mon, Jun 15, 2020 at 05:52:37PM +0200, Davide Prina wrote:
> I try to make a full debug. I never done that with a Python program, so I
> have searched on internet

Thanks!

> #3  0x000000000049d912 in Py_FatalError (msg=<optimized out>) at ../Python/pylifecycle.c:2197
> #4  0x00000000004b73b3 in PyEval_SaveThread () at ../Python/ceval.c:380
> #5  0x00007ffff43ac549 in  () at /usr/lib/python3/dist-packages/PyQt5/QtCore.cpython-38-x86_64-linux-gnu.so
> #6  0x00007ffff3f0c44c in QMetaObject::activate(QObject*, int, int, void**) () at /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
> #7  0x00007ffff43a643e in  () at /usr/lib/python3/dist-packages/PyQt5/QtCore.cpython-38-x86_64-linux-gnu.so
> #8  0x00000000005f1fca in cfunction_call_varargs (kwargs=<optimized out>, args=<optimized out>,
>     func=<built-in method emit of PyQt5.QtCore.pyqtBoundSignal object at remote 0x7fffbc357cf0>)
>     at ../Include/internal/pycore_pyerrors.h:13

So this seems to be the relevant part here.

I managed to reproduce this issue locally with some dbg packages installed,
and this part of stacktrace is as follows:

#9  0x000000000051cb0a in Py_FatalError (msg=msg at entry=0x6d9a88 "PyEval_SaveThread: NULL tstate") at ../Python/pylifecycle.c:2197
#10 0x00000000004db7d7 in PyEval_SaveThread () at ../Python/ceval.c:380
#11 0x00007ffff45f105c in qt_metacall_worker(sipSimpleWrapper*, PyTypeObject*, sipTypeDef*, QMetaObject::Call, int, void**)
    (pySelf=0x7fffc0522c30, pytype=<optimized out>, base=<optimized out>, _c=QMetaObject::InvokeMetaMethod, _id=19, _a=0x27ac0e0)
    at ../../qpy/QtCore/qpycore_qobject_helpers.cpp:106
#12 0x00007ffff413944c in QMetaObject::activate(QObject*, int, int, void**)
    (sender=0x20249a0, signalOffset=<optimized out>, local_signal_index=<optimized out>, argv=<optimized out>)
    at kernel/qobject.cpp:3821
#13 0x00007ffff45e9a9e in do_emit (sigargs=<optimized out>, docstring=<optimized out>, parsed_signature=0x144cb30,
    signal_index=<optimized out>, qtx=<optimized out>)
    at ../../qpy/QtCore/qpycore_pyqtboundsignal.cpp:801
#14 pyqtBoundSignal_emit(PyObject*, PyObject*) (self=<optimized out>, args=<optimized out>)
    at ../../qpy/QtCore/qpycore_pyqtboundsignal.cpp:742
#15 0x00000000004344fb in cfunction_call_varargs (func=0x7fffc20b5530, args=0x7ffff4923b40, kwargs=0x0) at ../Objects/call.c:757

It looks like a change in qpycore_qobject_helpers.cpp in PyQt 5.15 needed
a corresponding change in sip [1] that is part of sip 4.19.23, and all
dependent packages need to be rebuilt against that sip.

[1]: https://riverbankcomputing.com/hg/sip/rev/812b5e26df96

I will add a Breaks: against old pyqt5webengine to new pyqt5. Now that new
pyqt5webengine is already in testing, this is not urgent, but it will be
part of the next upload.

There is nothing I can do about this in pyqt5webengine, so I am closing the
bug filed against it.

--
Dmitry Shachnev
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 833 bytes
Desc: not available
URL: <http://alioth-lists.debian.net/pipermail/python-modules-team/attachments/20200616/346e9d37/attachment.sig>