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symbol lookup error: /lib/x86_64-linux-gnu/libQt5XcbQpa.so.5: undefined symbol: _ZN22QWindowSystemInterface24setPlatformFiltersEventsEb



  • Hello everyone!

    I'm a Python dev, and have got an interest in learning Qt for Python. I have tried to install and work with PyQt5 before, but it gave me "xcb" error and I did research about it and gave up later than and installed PySide, it worked. Today, I need to use a Python module named "mayavi" and it requires PyQt5. I tried to install it again with pip install pyqt5 and sudo apt install python3-pyqt5 and it gave me a "xcb" error again. I searched it on the forum a bit and solve my problem with creating a symbolic link. But now, it gives me another error whenever I try to open mayavi with mayavi2 command in my terminal -- note that, I could install mayavi module after solving xcb plugin error. Here is the error it gaves me:

    QFactoryLoader::QFactoryLoader() checking directory path "/usr/bin/platforms" ...
    QFactoryLoader::QFactoryLoader() looking at "/usr/bin/platforms/libqeglfs.so"
    Found metadata in lib /usr/lib/x86_64-linux-gnu/qt5/plugins/platforms/libqeglfs.so, metadata=
    {
        "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
        "MetaData": {
            "Keys": [
                "eglfs"
            ]
        },
        "archreq": 0,
        "className": "QEglFSIntegrationPlugin",
        "debug": false,
        "version": 330752
    }
    
    
    Got keys from plugin meta data ("eglfs")
    QFactoryLoader::QFactoryLoader() looking at "/usr/bin/platforms/libqlinuxfb.so"
    Found metadata in lib /usr/lib/x86_64-linux-gnu/qt5/plugins/platforms/libqlinuxfb.so, metadata=
    {
        "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
        "MetaData": {
            "Keys": [
                "linuxfb"
            ]
        },
        "archreq": 0,
        "className": "QLinuxFbIntegrationPlugin",
        "debug": false,
        "version": 330752
    }
    
    
    Got keys from plugin meta data ("linuxfb")
    QFactoryLoader::QFactoryLoader() looking at "/usr/bin/platforms/libqminimal.so"
    Found metadata in lib /usr/lib/x86_64-linux-gnu/qt5/plugins/platforms/libqminimal.so, metadata=
    {
        "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
        "MetaData": {
            "Keys": [
                "minimal"
            ]
        },
        "archreq": 0,
        "className": "QMinimalIntegrationPlugin",
        "debug": false,
        "version": 330752
    }
    
    
    Got keys from plugin meta data ("minimal")
    QFactoryLoader::QFactoryLoader() looking at "/usr/bin/platforms/libqminimalegl.so"
    Found metadata in lib /usr/lib/x86_64-linux-gnu/qt5/plugins/platforms/libqminimalegl.so, metadata=
    {
        "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
        "MetaData": {
            "Keys": [
                "minimalegl"
            ]
        },
        "archreq": 0,
        "className": "QMinimalEglIntegrationPlugin",
        "debug": false,
        "version": 330752
    }
    
    
    Got keys from plugin meta data ("minimalegl")
    QFactoryLoader::QFactoryLoader() looking at "/usr/bin/platforms/libqoffscreen.so"
    Found metadata in lib /usr/lib/x86_64-linux-gnu/qt5/plugins/platforms/libqoffscreen.so, metadata=
    {
        "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
        "MetaData": {
            "Keys": [
                "offscreen"
            ]
        },
        "archreq": 0,
        "className": "QOffscreenIntegrationPlugin",
        "debug": false,
        "version": 330752
    }
    
    
    Got keys from plugin meta data ("offscreen")
    QFactoryLoader::QFactoryLoader() looking at "/usr/bin/platforms/libqvnc.so"
    Found metadata in lib /usr/lib/x86_64-linux-gnu/qt5/plugins/platforms/libqvnc.so, metadata=
    {
        "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
        "MetaData": {
            "Keys": [
                "vnc"
            ]
        },
        "archreq": 0,
        "className": "QVncIntegrationPlugin",
        "debug": false,
        "version": 330752
    }
    
    
    Got keys from plugin meta data ("vnc")
    QFactoryLoader::QFactoryLoader() looking at "/usr/bin/platforms/libqxcb.so"
    Found metadata in lib /usr/lib/x86_64-linux-gnu/qt5/plugins/platforms/libqxcb.so, metadata=
    {
        "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
        "MetaData": {
            "Keys": [
                "xcb"
            ]
        },
        "archreq": 0,
        "className": "QXcbIntegrationPlugin",
        "debug": false,
        "version": 330752
    }
    
    
    Got keys from plugin meta data ("xcb")
    loaded library "/usr/lib/x86_64-linux-gnu/qt5/plugins/platforms/libqxcb.so"
    /media/xyz49/Data/Projeler/Yazılım/Python/3D-Game-of-Life-stable/bin/python: symbol lookup error: /lib/x86_64-linux-gnu/libQt5XcbQpa.so.5: undefined symbol: _ZN22QWindowSystemInterface24setPlatformFiltersEventsEb, version Qt_5_PRIVATE_API
    

    Is there any advice for me to solve this problem? I'm using Ubuntu 20.04.2 LTS. Some (incase if it is important) outputs:

    ~$ qmake --version
    QMake version 3.1
    Using Qt version 5.12.8 in /usr/lib/x86_64-linux-gnu
    
    ❯ apt list --installed | grep qt
    
    WARNING: apt does not have a stable CLI interface. Use with caution in scripts.
    
    libgsettings-qt1/focal,now 0.2-1 amd64 [installed,automatic]
    libqt5concurrent5/focal,now 5.12.8+dfsg-0ubuntu1 amd64 [installed,automatic]
    libqt5core5a/focal,now 5.12.8+dfsg-0ubuntu1 amd64 [installed,automatic]
    libqt5dbus5/focal,now 5.12.8+dfsg-0ubuntu1 amd64 [installed,automatic]
    libqt5designer5/focal,now 5.12.8-0ubuntu1 amd64 [installed,automatic]
    libqt5designercomponents5/focal,now 5.12.8-0ubuntu1 amd64 [installed,automatic]
    libqt5gui5/focal,now 5.12.8+dfsg-0ubuntu1 amd64 [installed,automatic]
    libqt5help5/focal,now 5.12.8-0ubuntu1 amd64 [installed,automatic]
    libqt5multimedia5/focal,now 5.12.8-0ubuntu1 amd64 [installed,automatic]
    libqt5network5/focal,now 5.12.8+dfsg-0ubuntu1 amd64 [installed,automatic]
    libqt5opengl5-dev/focal,now 5.12.8+dfsg-0ubuntu1 amd64 [installed,automatic]
    libqt5opengl5/focal,now 5.12.8+dfsg-0ubuntu1 amd64 [installed,automatic]
    libqt5positioning5/focal,now 5.12.8+dfsg-0ubuntu1 amd64 [installed,automatic]
    libqt5printsupport5/focal,now 5.12.8+dfsg-0ubuntu1 amd64 [installed,automatic]
    libqt5qml5/focal,now 5.12.8-0ubuntu1 amd64 [installed,automatic]
    libqt5quick5/focal,now 5.12.8-0ubuntu1 amd64 [installed,automatic]
    libqt5quickwidgets5/focal,now 5.12.8-0ubuntu1 amd64 [installed,automatic]
    libqt5sensors5/focal,now 5.12.8-0ubuntu1 amd64 [installed,automatic]
    libqt5sql5-sqlite/focal,now 5.12.8+dfsg-0ubuntu1 amd64 [installed,automatic]
    libqt5sql5/focal,now 5.12.8+dfsg-0ubuntu1 amd64 [installed,automatic]
    libqt5svg5/focal,now 5.12.8-0ubuntu1 amd64 [installed,automatic]
    libqt5test5/focal,now 5.12.8+dfsg-0ubuntu1 amd64 [installed,automatic]
    libqt5webchannel5/focal,now 5.12.8-0ubuntu1 amd64 [installed,automatic]
    libqt5webkit5/focal,now 5.212.0~alpha4-1ubuntu2 amd64 [installed,automatic]
    libqt5widgets5/focal,now 5.12.8+dfsg-0ubuntu1 amd64 [installed,automatic]
    libqt5x11extras5/focal,now 5.12.8-0ubuntu1 amd64 [installed,automatic]
    libqt5xml5/focal,now 5.12.8+dfsg-0ubuntu1 amd64 [installed,automatic]
    pyqt5-dev-tools/focal,now 5.14.1+dfsg-3build1 amd64 [installed]
    python3-pyqt5/focal,now 5.14.1+dfsg-3build1 amd64 [installed]
    qdoc-qt5/focal,now 5.12.8-0ubuntu1 amd64 [installed,automatic]
    qhelpgenerator-qt5/focal,now 5.12.8-0ubuntu1 amd64 [installed,automatic]
    qml-module-qtgraphicaleffects/focal,now 5.12.8-0ubuntu1 amd64 [installed,automatic]
    qml-module-qtquick-controls/focal,now 5.12.8-0ubuntu2 amd64 [installed,automatic]
    qml-module-qtquick-dialogs/focal,now 5.12.8-0ubuntu2 amd64 [installed,automatic]
    qml-module-qtquick-layouts/focal,now 5.12.8-0ubuntu1 amd64 [installed,automatic]
    qml-module-qtquick-privatewidgets/focal,now 5.12.8-0ubuntu2 amd64 [installed,automatic]
    qml-module-qtquick-window2/focal,now 5.12.8-0ubuntu1 amd64 [installed,automatic]
    qml-module-qtquick2/focal,now 5.12.8-0ubuntu1 amd64 [installed,automatic]
    qt5-assistant/focal,now 5.12.8-0ubuntu1 amd64 [installed,automatic]
    qt5-default/focal,now 5.12.8+dfsg-0ubuntu1 amd64 [installed]
    qt5-gtk-platformtheme/focal,now 5.12.8+dfsg-0ubuntu1 amd64 [installed,automatic]
    qt5-qmake-bin/focal,now 5.12.8+dfsg-0ubuntu1 amd64 [installed,automatic]
    qt5-qmake/focal,now 5.12.8+dfsg-0ubuntu1 amd64 [installed,automatic]
    qtattributionsscanner-qt5/focal,now 5.12.8-0ubuntu1 amd64 [installed,automatic]
    qtbase5-dev-tools/focal,now 5.12.8+dfsg-0ubuntu1 amd64 [installed,automatic]
    qtbase5-dev/focal,now 5.12.8+dfsg-0ubuntu1 amd64 [installed,automatic]
    qtchooser/focal,now 66-2build1 amd64 [installed,automatic]
    qttools5-dev-tools/focal,now 5.12.8-0ubuntu1 amd64 [installed]
    qttranslations5-l10n/focal,focal,now 5.12.8-0ubuntu1 all [installed,automatic]
    vlc-plugin-qt/focal,now 3.0.9.2-1 amd64 [installed,automatic]
    
    

    ~$ ls /usr/lib/x86_64-linux-gnu/ | grep qt
    lrwxrwxrwx 1 root root 24 Feb 18 2020 libgsettings-qt.so.1 -> libgsettings-qt.so.1.0.0
    lrwxrwxrwx 1 root root 24 Feb 18 2020 libgsettings-qt.so.1.0 -> libgsettings-qt.so.1.0.0
    -rw-r--r-- 1 root root 55K Feb 18 2020 libgsettings-qt.so.1.0.0
    drwxr-xr-x 7 root root 4.0K Feb 28 00:44 qt5
    drwxr-xr-x 2 root root 4.0K Feb 28 00:44 qtchooser
    drwxr-xr-x 3 root root 4.0K Feb 28 00:02 qt-default

    Note: You can see my qt5 folder in tree view from the link here: https://pastebin.ubuntu.com/p/Chp75wyw5q/
    
    Thank you everyone.

  • Lifetime Qt Champion

    Hi and welcome to devnet,

    How many different versions of Python do you have ?
    It looks like you are using a custom one.
    Are you using a virtual env ? Conda ? Just your system Python (does not look it though) ?


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