Uploaded image for project: 'Qt'
  1. Qt
  2. QTBUG-84749

QT applications fail to run if xcb_xinerama (or other xcb libraries) is not installed

    XMLWordPrintable

Details

    • Linux/X11

    Description

      Getting the error message when trying to run any sample application

       

      qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found.
This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.
Available platform plugins are: eglfs, linuxfb, minimal, minimalegl, offscreen, vnc, wayland-egl, wayland, wayland-xcomposite-egl, wayland-xcomposite-glx, xcb.

       

      Using Ubuntu 20.04 LTS, gnome 3.36.2 on X11; Qt Creator 4.12.2 and Qt 5.15.0 installed from Qt binary download; gcc 9.3.0

      Setting QT_DEBUG_PLUGINS to 1 gives:

       

      QFactoryLoader::QFactoryLoader() checking directory path "/home/myk/Qt/5.15.0/gcc_64/plugins/platforms" ...
QFactoryLoader::QFactoryLoader() looking at "/home/myk/Qt/5.15.0/gcc_64/plugins/platforms/libqeglfs.so"
Found metadata in lib /home/myk/Qt/5.15.0/gcc_64/plugins/platforms/libqeglfs.so, metadata=
{
 "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
 "MetaData": {
 "Keys": [
 "eglfs"
 ]
 },
 "archreq": 0,
 "className": "QEglFSIntegrationPlugin",
 "debug": false,
 "version": 331520
}

Got keys from plugin meta data ("eglfs")
QFactoryLoader::QFactoryLoader() looking at "/home/myk/Qt/5.15.0/gcc_64/plugins/platforms/libqlinuxfb.so"
Found metadata in lib /home/myk/Qt/5.15.0/gcc_64/plugins/platforms/libqlinuxfb.so, metadata=
{
 "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
 "MetaData": {
 "Keys": [
 "linuxfb"
 ]
 },
 "archreq": 0,
 "className": "QLinuxFbIntegrationPlugin",
 "debug": false,
 "version": 331520
}

Got keys from plugin meta data ("linuxfb")
QFactoryLoader::QFactoryLoader() looking at "/home/myk/Qt/5.15.0/gcc_64/plugins/platforms/libqminimal.so"
Found metadata in lib /home/myk/Qt/5.15.0/gcc_64/plugins/platforms/libqminimal.so, metadata=
{
 "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
 "MetaData": {
 "Keys": [
 "minimal"
 ]
 },
 "archreq": 0,
 "className": "QMinimalIntegrationPlugin",
 "debug": false,
 "version": 331520
}

Got keys from plugin meta data ("minimal")
QFactoryLoader::QFactoryLoader() looking at "/home/myk/Qt/5.15.0/gcc_64/plugins/platforms/libqminimalegl.so"
Found metadata in lib /home/myk/Qt/5.15.0/gcc_64/plugins/platforms/libqminimalegl.so, metadata=
{
 "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
 "MetaData": {
 "Keys": [
 "minimalegl"
 ]
 },
 "archreq": 0,
 "className": "QMinimalEglIntegrationPlugin",
 "debug": false,
 "version": 331520
}

Got keys from plugin meta data ("minimalegl")
QFactoryLoader::QFactoryLoader() looking at "/home/myk/Qt/5.15.0/gcc_64/plugins/platforms/libqoffscreen.so"
Found metadata in lib /home/myk/Qt/5.15.0/gcc_64/plugins/platforms/libqoffscreen.so, metadata=
{
 "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
 "MetaData": {
 "Keys": [
 "offscreen"
 ]
 },
 "archreq": 0,
 "className": "QOffscreenIntegrationPlugin",
 "debug": false,
 "version": 331520
}

Got keys from plugin meta data ("offscreen")
QFactoryLoader::QFactoryLoader() looking at "/home/myk/Qt/5.15.0/gcc_64/plugins/platforms/libqvnc.so"
Found metadata in lib /home/myk/Qt/5.15.0/gcc_64/plugins/platforms/libqvnc.so, metadata=
{
 "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
 "MetaData": {
 "Keys": [
 "vnc"
 ]
 },
 "archreq": 0,
 "className": "QVncIntegrationPlugin",
 "debug": false,
 "version": 331520
}

Got keys from plugin meta data ("vnc")
QFactoryLoader::QFactoryLoader() looking at "/home/myk/Qt/5.15.0/gcc_64/plugins/platforms/libqwayland-egl.so"
Found metadata in lib /home/myk/Qt/5.15.0/gcc_64/plugins/platforms/libqwayland-egl.so, metadata=
{
 "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
 "MetaData": {
 "Keys": [
 "wayland-egl"
 ]
 },
 "archreq": 0,
 "className": "QWaylandEglPlatformIntegrationPlugin",
 "debug": false,
 "version": 331520
}

Got keys from plugin meta data ("wayland-egl")
QFactoryLoader::QFactoryLoader() looking at "/home/myk/Qt/5.15.0/gcc_64/plugins/platforms/libqwayland-generic.so"
Found metadata in lib /home/myk/Qt/5.15.0/gcc_64/plugins/platforms/libqwayland-generic.so, metadata=
{
 "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
 "MetaData": {
 "Keys": [
 "wayland"
 ]
 },
 "archreq": 0,
 "className": "QWaylandIntegrationPlugin",
 "debug": false,
 "version": 331520
}

Got keys from plugin meta data ("wayland")
QFactoryLoader::QFactoryLoader() looking at "/home/myk/Qt/5.15.0/gcc_64/plugins/platforms/libqwayland-xcomposite-egl.so"
Found metadata in lib /home/myk/Qt/5.15.0/gcc_64/plugins/platforms/libqwayland-xcomposite-egl.so, metadata=
{
 "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
 "MetaData": {
 "Keys": [
 "wayland-xcomposite-egl"
 ]
 },
 "archreq": 0,
 "className": "QWaylandXCompositeEglPlatformIntegrationPlugin",
 "debug": false,
 "version": 331520
}

Got keys from plugin meta data ("wayland-xcomposite-egl")
QFactoryLoader::QFactoryLoader() looking at "/home/myk/Qt/5.15.0/gcc_64/plugins/platforms/libqwayland-xcomposite-glx.so"
Found metadata in lib /home/myk/Qt/5.15.0/gcc_64/plugins/platforms/libqwayland-xcomposite-glx.so, metadata=
{
 "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
 "MetaData": {
 "Keys": [
 "wayland-xcomposite-glx"
 ]
 },
 "archreq": 0,
 "className": "QWaylandXCompositeGlxPlatformIntegrationPlugin",
 "debug": false,
 "version": 331520
}

Got keys from plugin meta data ("wayland-xcomposite-glx")
QFactoryLoader::QFactoryLoader() looking at "/home/myk/Qt/5.15.0/gcc_64/plugins/platforms/libqxcb.so"
Found metadata in lib /home/myk/Qt/5.15.0/gcc_64/plugins/platforms/libqxcb.so, metadata=
{
 "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
 "MetaData": {
 "Keys": [
 "xcb"
 ]
 },
 "archreq": 0,
 "className": "QXcbIntegrationPlugin",
 "debug": false,
 "version": 331520
}

Got keys from plugin meta data ("xcb")
QFactoryLoader::QFactoryLoader() checking directory path "/home/myk/Qt/Examples/Qt-5.15.0/datavisualization/build-bars-Desktop_Qt_5_15_0_GCC_64bit-Debug/platforms" ...
Cannot load library /home/myk/Qt/5.15.0/gcc_64/plugins/platforms/libqxcb.so: (libxcb-xinerama.so.0: cannot open shared object file: No such file or directory)
QLibraryPrivate::loadPlugin failed on "/home/myk/Qt/5.15.0/gcc_64/plugins/platforms/libqxcb.so" : "Cannot load library /home/myk/Qt/5.15.0/gcc_64/plugins/platforms/libqxcb.so: (libxcb-xinerama.so.0: cannot open shared object file: No such file or directory)"
qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found.
This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.
Available platform plugins are: eglfs, linuxfb, minimal, minimalegl, offscreen, vnc, wayland-egl, wayland, wayland-xcomposite-egl, wayland-xcomposite-glx, xcb.
16:33:14: The program has unexpectedly finished.
 

      Investigating at the command line:

      myk@ubuntu:~$ find . -name libqxcb.so -print
      ./Qt/5.15.0/gcc_64/plugins/platforms/libqxcb.so
      ./Qt/Tools/QtCreator/lib/Qt/plugins/platforms/libqxcb.so

      myk@ubuntu:~$ ldd ./Qt/5.15.0/gcc_64/plugins/platforms/libqxcb.so | grep xinerama
      libxcb-xinerama.so.0 => not found
      libxcb-xinerama.so.0 => not found

       

      To Resolve:
      myk@ubuntu:~$ sudo apt-get install -y libxcb-xinerama0
      Reading package lists... Done
      Building dependency tree
      Reading state information... Done
      The following NEW packages will be installed:
      libxcb-xinerama0
      0 upgraded, 1 newly installed, 0 to remove and 26 not upgraded.
      Need to get 5,260 B of archives.
      After this operation, 37.9 kB of additional disk space will be used.
      Get:1 http://us.archive.ubuntu.com/ubuntu focal/main amd64 libxcb-xinerama0 amd64 1.14-2 [5,260 B]
      Fetched 5,260 B in 1s (8,710 B/s)
      Selecting previously unselected package libxcb-xinerama0:amd64.
      (Reading database ... 233716 files and directories currently installed.)
      Preparing to unpack .../libxcb-xinerama0_1.14-2_amd64.deb ...
      Unpacking libxcb-xinerama0:amd64 (1.14-2) ...
      Setting up libxcb-xinerama0:amd64 (1.14-2) ...
      Processing triggers for libc-bin (2.31-0ubuntu9) ...
      myk@ubuntu:~$ ldd ./Qt/5.15.0/gcc_64/plugins/platforms/libqxcb.so | grep xinerama
      libxcb-xinerama.so.0 => /lib/x86_64-linux-gnu/libxcb-xinerama.so.0 (0x00007fc158fb2000)

      Application now runs successfully

      Expected:

      It would be great for new installations of Qt Creator on Ubuntu  to work out the box, failing which perhaps this dependency be documented somewhere if that is not already done.

      Attachments

        Issue Links

          is duplicated by

          Bug - A problem which impairs or prevents the functions of the product. QTBUG-88727 Reinstall qt 6 after update fails - reinstall results the same; Qt will not run

          • Not Evaluated - Not yet evaluated/prioritized
          • Closed

          Bug - A problem which impairs or prevents the functions of the product. QTCREATORBUG-24964 Qt creator v6 will not start after applying latest update

          • Not Evaluated - Not yet evaluated/prioritized
          • Closed
          relates to

          Bug - A problem which impairs or prevents the functions of the product. QTBUG-89754 Reg->6.0/Linux/CMake build : QtGui has dependency on libopengl0 and opengl headers

          • P2: Important - Urgent, should be fixed, but will not stop the release.
          • Open

          Bug - A problem which impairs or prevents the functions of the product. QTBUG-108796 Some examples crash when running with Qt 6.5 kit

          • Not Evaluated - Not yet evaluated/prioritized
          • Closed

          Bug - A problem which impairs or prevents the functions of the product. QTBUG-88688 Qt application fails to start on Debian 10 Buster because libqxcb.so requires missing libxcb-util.so.1

          • P1: Critical - Urgent and Important, will STOP the release if matched with set FixVersion field. This includes regressions from the last version that are not edge cases; Data loss; Build issues; All but the most unlikely crashes/lockups/hanging; Serious usability issues and embarrassing bugs & Bugs critical to a deliverable. This is the highest possible priority for requirements.
          • Closed

          Bug - A problem which impairs or prevents the functions of the product. QTBUG-94244 [Regression] Qt 5.12 installers no longer work out-of-the-box on Linux

          • P1: Critical - Urgent and Important, will STOP the release if matched with set FixVersion field. This includes regressions from the last version that are not edge cases; Data loss; Build issues; All but the most unlikely crashes/lockups/hanging; Serious usability issues and embarrassing bugs & Bugs critical to a deliverable. This is the highest possible priority for requirements.
          • Closed
          replaces

          Bug - A problem which impairs or prevents the functions of the product. QTCREATORBUG-24732 Installing default QtCreator on a default Ubuntu 20.04 results in unusable configuration

          • Not Evaluated - Not yet evaluated/prioritized
          • Closed

          Bug - A problem which impairs or prevents the functions of the product. QTCREATORBUG-24962 QtCreator: qt.qpa.plugin: Could not load the Qt platform plugin "xcb". libxcb-util.so.1 - no such file

          • Not Evaluated - Not yet evaluated/prioritized
          • Closed

          Bug - A problem which impairs or prevents the functions of the product. QTCREATORBUG-24967 t.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found.

          • Not Evaluated - Not yet evaluated/prioritized
          • Closed
          resulted in

          Bug - A problem which impairs or prevents the functions of the product. QTCREATORBUG-24711 failure to launch when libxcb-xinema0 not installed

          • Not Evaluated - Not yet evaluated/prioritized
          • Closed

          Bug - A problem which impairs or prevents the functions of the product. QTCREATORBUG-24561 Qt Creator depends on xcb libraries that are not necessarily installed by default

          • P2: Important - Urgent, should be fixed, but will not stop the release.
          • Closed

          Bug - A problem which impairs or prevents the functions of the product. QTIFW-2557 online installer 4.3.0 requires libxcb-xinerama.so

          • P2: Important - Urgent, should be fixed, but will not stop the release.
          • Closed
          No reviews matched the request. Check your Options in the drop-down menu of this sections header.

          Activity

            People

              releaseteam Qt Release Team
              myk Michael Arnold
              Votes:
              14 Vote for this issue
              Watchers:
              39 Start watching this issue

              Dates

                Created:
                Updated:
                Resolved:

                Gerrit Reviews

                  There are no open Gerrit changes