Arch Linux

ndewy

Member

Registered: 2021-05-16

Posts: 3

[SOLVED] Python/QT5 - Back In Time fails to run due to PyQT5 error.

Hello,
I have been trying to install the backup utility Back In Time onto my Arch Linux system.
It installs with no issues (using the AUR package).
However, upon running, it fails to launch, giving the following output:

[niklas@niklas-desktop ~]$ backintime-qt

Back In Time
Version: 1.2.1

Back In Time comes with ABSOLUTELY NO WARRANTY.
This is free software, and you are welcome to redistribute it
under certain conditions; type `backintime --license' for details.

python: symbol lookup error: /usr/lib/python3.9/site-packages/PyQt5/Qt5/plugins/platforms/../../lib/libQt5DBus.so.5: undefined symbol: _ZdlPvm, version Qt_5

This happens regardless of whether I install using the backintime or backintime-git AUR packages. I have also tried building from source, which also produces the same result.

Package Versions

[niklas@niklas-desktop ~]$ pacman -Q | grep -E 'qt5|python-keyring|python-dbus|python-pyqt5|libnotify|python-k|dbus-python|xorg-xdpyinfo|backintime'
backintime 1.2.1-1
backintime-cli 1.2.1-1
dbus-python 1.2.16-4
libdbusmenu-qt5 0.9.3+16.04.20160218-5
libnotify 0.7.9-1
phonon-qt5 4.11.1-2
phonon-qt5-gstreamer 4.10.0-2
polkit-qt5 0.113.0-2
python-keyring 23.0.1-1latest
python-pyqt5 5.15.4-1
python-pyqt5-sip 12.8.1-3
qt5-base 5.15.2+kde+r192-1
qt5-declarative 5.15.2+kde+r24-1
qt5-graphicaleffects 5.15.2-1
qt5-imageformats 5.15.2-1
qt5-location 5.15.2-3
qt5-multimedia 5.15.2-1
qt5-quickcontrols 5.15.2-1
qt5-quickcontrols2 5.15.2-1
qt5-script 5.15.2-1
qt5-sensors 5.15.2-1
qt5-speech 5.15.2-1
qt5-svg 5.15.2+kde+r7-1
qt5-tools 5.15.2+kde+r17-1
qt5-translations 5.15.2-1
qt5-wayland 5.15.2+kde+r22-1
qt5-webchannel 5.15.2-1
qt5-webengine 5.15.3-5
qt5-webkit 5.212.0alpha4-10
qt5-websockets 5.15.2-1
qt5-x11extras 5.15.2-1
qt5-xmlpatterns 5.15.2-1
xorg-xdpyinfo 1.3.2-4

Thank you.

Last edited by ndewy (2021-05-16 17:10:23)

arojas

Developer

From: Spain

Registered: 2011-10-09

Posts: 2,151

Re: [SOLVED] Python/QT5 - Back In Time fails to run due to PyQT5 error.

This is because you have installed pyqt5 from pip. Remove all traces of it and reinstall everything from the official repos (and stop installing stuff with pip as root)

ndewy

Member

Registered: 2021-05-16

Posts: 3

Re: [SOLVED] Python/QT5 - Back In Time fails to run due to PyQT5 error.

Thank you, this worked.
Even though I already tried this for PyQt5 before posting, I did not realize until I did pip list just now that PyQt5-PyQt5 and PyQt5.Sip also existed. Reinstalling PyQt5.Sip through pacman fixed the issue.