Important: Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

Built Qt6 from sources, problem with xcb plugin



  • Hi Friends, There is another topic about this but it is old and does not provide a solution, so I ask here for some help:

    I have compiled Qt6 on Linux Mint 19, but the QPA plugin for xcb is not generated, so my App does not run.

    This is my configure summary:

    Configure summary:
    
    Building for: linux-clang (x86_64, CPU features: mmx sse sse2)
    Compiler: clang 11.0.1
    Build options:
      Mode ................................... debug
      Fully optimize release builds (-O3) .... no
      Building shared libraries .............. yes
      Using C standard ....................... C11
      Using C++ standard ..................... C++17
      Using ccache ........................... no
      enable_new_dtags ....................... no
      Relocatable ............................ yes
      Using precompiled headers .............. yes
      Using LTCG ............................. no
      Target compiler supports:
        SSE .................................. SSE2 SSE3 SSSE3 SSE4.1 SSE4.2
        AVX .................................. AVX AVX2
        AVX512 ............................... F ER CD PF DQ BW VL IFMA VBMI
        Other x86 ............................ F16C RDRAND
        Intrinsics without -mXXX option ...... yes
      Sanitizers:
        Addresses ............................ no
        Threads .............................. no
        Memory ............................... no
        Fuzzer (instrumentation only) ........ no
        Undefined ............................ no
      Build parts ............................ libs tools
    Qt modules and options:
      Qt Concurrent .......................... yes
      Qt D-Bus ............................... yes
      Qt D-Bus directly linked to libdbus .... yes
      Qt Gui ................................. yes
      Qt Network ............................. yes
      Qt Sql ................................. yes
      Qt Testlib ............................. yes
      Qt Widgets ............................. yes
      Qt Xml ................................. yes
    Support enabled for:
      Using pkg-config ....................... yes
      udev ................................... yes
      Using system zlib ...................... yes
      Zstandard support ...................... no
    Qt Core:
      DoubleConversion ....................... yes
        Using system DoubleConversion ........ no
      GLib ................................... yes
      ICU .................................... yes
      Using system libb2 ..................... no
      Built-in copy of the MIME database ..... yes
      Tracing backend ........................ <none>
      Logging backends:
        journald ............................. no
        syslog ............................... no
        slog2 ................................ no
      PCRE2 .................................. yes
        Using system PCRE2 ................... no
      CLONE_PIDFD support in forkfd .......... yes
    Qt Sql:
      SQL item models ........................ yes
    Qt Network:
      getifaddrs() ........................... yes
      IPv6 ifname ............................ yes
      libproxy ............................... no
      Linux AF_NETLINK ....................... yes
      OpenSSL ................................ yes
        Qt directly linked to OpenSSL ........ no
      OpenSSL 1.1 ............................ yes
      DTLS ................................... yes
      OCSP-stapling .......................... yes
      SCTP ................................... no
      Use system proxies ..................... yes
      GSSAPI ................................. no
      Brotli Decompression Support ........... no
    Qt Gui:
      Accessibility .......................... yes
      FreeType ............................... yes
        Using system FreeType ................ yes
      HarfBuzz ............................... yes
        Using system HarfBuzz ................ no
      Fontconfig ............................. yes
      Image formats:
        GIF .................................. yes
        ICO .................................. yes
        JPEG ................................. yes
          Using system libjpeg ............... no
        PNG .................................. yes
          Using system libpng ................ yes
      Text formats:
        HtmlParser ........................... yes
        CssParser ............................ yes
        OdfWriter ............................ yes
        MarkdownReader ....................... yes
          Using system libmd4c ............... no
        MarkdownWriter ....................... yes
      EGL .................................... yes
      OpenVG ................................. no
      OpenGL:
        Desktop OpenGL ....................... yes
        OpenGL ES 2.0 ........................ no
        OpenGL ES 3.0 ........................ no
        OpenGL ES 3.1 ........................ no
        OpenGL ES 3.2 ........................ no
      Vulkan ................................. no
      Session Management ..................... yes
    Features used by QPA backends:
      evdev .................................. yes
      libinput ............................... no
      INTEGRITY HID .......................... no
      mtdev .................................. no
      tslib .................................. no
      xkbcommon .............................. yes
      X11 specific:
        XLib ................................. yes
        XCB Xlib ............................. no
        EGL on X11 ........................... yes
        xkbcommon-x11 ........................ no
    QPA backends:
      DirectFB ............................... no
      EGLFS .................................. yes
      EGLFS details:
        EGLFS OpenWFD ........................ no
        EGLFS i.Mx6 .......................... no
        EGLFS i.Mx6 Wayland .................. no
        EGLFS RCAR ........................... no
        EGLFS EGLDevice ...................... yes
        EGLFS GBM ............................ no
        EGLFS VSP2 ........................... no
        EGLFS Mali ........................... no
        EGLFS Raspberry Pi ................... no
        EGLFS X11 ............................ no
      LinuxFB ................................ yes
      VNC .................................... yes
      QNX:
        lgmon ................................ no
        IMF .................................. no
      XCB:
        Using system-provided xcb-xinput ..... no
        Native painting (experimental) ....... no
        GL integrations:
          GLX Plugin ......................... no
            XCB GLX .......................... no
          EGL-X11 Plugin ..................... no
      Windows:
        Direct 2D ............................ no
        Direct 2D 1.1 ........................ no
        DirectWrite .......................... no
        DirectWrite 3 ........................ no
    Qt Widgets:
      GTK+ ................................... yes
      Styles ................................. Fusion Windows
    Qt Testlib:
      Tester for item models ................. yes
    Qt PrintSupport:
      CUPS ................................... no
    Qt Sql Drivers:
      DB2 (IBM) .............................. no
      InterBase .............................. no
      MySql .................................. no
      OCI (Oracle) ........................... no
      ODBC ................................... no
      PostgreSQL ............................. yes
      SQLite ................................. yes
        Using system provided SQLite ......... no
    Qt 5 Compatibility Libraries:
      iconv .................................. no
    Qt QML:
      QML network support .................... yes
      QML debugging and profiling support .... yes
      QML just-in-time compiler .............. yes
      QML sequence object .................... yes
      QML XML http request ................... yes
      QML Locale ............................. yes
    Qt QML Models:
      QML list model ......................... yes
      QML delegate model ..................... yes
    Qt Quick:
      AnimatedImage item ..................... yes
      Canvas item ............................ yes
      Support for Qt Quick Designer .......... yes
      Flipable item .......................... yes
      GridView item .......................... yes
      ListView item .......................... yes
      TableView item ......................... yes
      Path support ........................... yes
      PathView item .......................... yes
      Positioner items ....................... yes
      Repeater item .......................... yes
      ShaderEffect item ...................... yes
      Sprite item ............................ yes
    Qt Tools:
      Qt Assistant ........................... yes
      QDoc ................................... no
      Clang-based lupdate parser ............. no
      Qt Designer ............................ yes
      Qt Distance Field Generator ............ yes
      kmap2qmap .............................. yes
      Qt Linguist ............................ yes
      Mac Deployment Tool .................... no
      pixeltool .............................. yes
      qdbus .................................. yes
      qev .................................... yes
      Qt Attributions Scanner ................ yes
      qtdiag ................................. yes
      qtpaths ................................ yes
      qtplugininfo ........................... yes
      Windows deployment tool ................ no
    Qt Quick Templates 2:
      Hover support .......................... yes
      Multi-touch support .................... yes
    Qt Quick Controls 2:
      Styles ................................. Basic Fusion Imagine Material Universal macOS Windows
    QtQuick3D:
      Assimp ................................. yes
      System Assimp .......................... no
    
    

    All libxcb*-dev libcxb* packages are installed an detected by configure script, but it appears to be not recognized in the summary.

    Thanks in adavance for any help.


  • Lifetime Qt Champion

    Hi,

    You should check the test logs to see exactly what failed. You are likely missing a dependency related to xcb like xkbcommon.



  • @SGaist said in Built Qt6 from sources, problem with xcb plugin:

    xkbcommon

    This is my list of installed deps:

    ➜  ~ dpkg -la | grep xcb
    ii  libx11-xcb-dev:amd64                       2:1.6.4-3ubuntu0.3                                              amd64        Xlib/XCB interface library (development headers)
    ii  libx11-xcb1:amd64                          2:1.6.4-3ubuntu0.3                                              amd64        Xlib/XCB interface library
    ii  libxcb-composite0:amd64                    1.13-2~ubuntu18.04                                              amd64        X C Binding, composite extension
    ii  libxcb-composite0-dev:amd64                1.13-2~ubuntu18.04                                              amd64        X C Binding, composite extension, development files
    ii  libxcb-cursor-dev:amd64                    0.1.1-4ubuntu1                                                  amd64        utility libraries for X C Binding -- cursor, development files
    ii  libxcb-cursor0:amd64                       0.1.1-4ubuntu1                                                  amd64        utility libraries for X C Binding -- cursor
    ii  libxcb-damage0:amd64                       1.13-2~ubuntu18.04                                              amd64        X C Binding, damage extension
    ii  libxcb-damage0-dev:amd64                   1.13-2~ubuntu18.04                                              amd64        X C Binding, damage extension, development files
    ii  libxcb-dpms0:amd64                         1.13-2~ubuntu18.04                                              amd64        X C Binding, dpms extension
    ii  libxcb-dpms0-dev:amd64                     1.13-2~ubuntu18.04                                              amd64        X C Binding, dpms extension, development files
    ii  libxcb-dri2-0:amd64                        1.13-2~ubuntu18.04                                              amd64        X C Binding, dri2 extension
    ii  libxcb-dri2-0-dev:amd64                    1.13-2~ubuntu18.04                                              amd64        X C Binding, dri2 extension, development files
    ii  libxcb-dri3-0:amd64                        1.13-2~ubuntu18.04                                              amd64        X C Binding, dri3 extension
    ii  libxcb-dri3-dev:amd64                      1.13-2~ubuntu18.04                                              amd64        X C Binding, dri3 extension, development files
    ii  libxcb-ewmh-dev:amd64                      0.4.1-1ubuntu1                                                  amd64        utility libraries for X C Binding -- ewmh, development files
    ii  libxcb-ewmh2:amd64                         0.4.1-1ubuntu1                                                  amd64        utility libraries for X C Binding -- ewmh
    ii  libxcb-glx0:amd64                          1.13-2~ubuntu18.04                                              amd64        X C Binding, glx extension
    ii  libxcb-glx0-dev:amd64                      1.13-2~ubuntu18.04                                              amd64        X C Binding, glx extension, development files
    ii  libxcb-icccm4:amd64                        0.4.1-1ubuntu1                                                  amd64        utility libraries for X C Binding -- icccm
    ii  libxcb-icccm4-dev:amd64                    0.4.1-1ubuntu1                                                  amd64        utility libraries for X C Binding -- icccm, development files
    ii  libxcb-image0:amd64                        0.4.0-1build1                                                   amd64        utility libraries for X C Binding -- image
    ii  libxcb-image0-dev:amd64                    0.4.0-1build1                                                   amd64        utility libraries for X C Binding -- image, development files
    ii  libxcb-keysyms1:amd64                      0.4.0-1                                                         amd64        utility libraries for X C Binding -- keysyms
    ii  libxcb-keysyms1-dev:amd64                  0.4.0-1                                                         amd64        utility libraries for X C Binding -- keysyms, development files
    ii  libxcb-present-dev:amd64                   1.13-2~ubuntu18.04                                              amd64        X C Binding, present extension, development files
    ii  libxcb-present0:amd64                      1.13-2~ubuntu18.04                                              amd64        X C Binding, present extension
    ii  libxcb-randr0:amd64                        1.13-2~ubuntu18.04                                              amd64        X C Binding, randr extension
    ii  libxcb-randr0-dev:amd64                    1.13-2~ubuntu18.04                                              amd64        X C Binding, randr extension, development files
    ii  libxcb-record0:amd64                       1.13-2~ubuntu18.04                                              amd64        X C Binding, record extension
    ii  libxcb-record0-dev:amd64                   1.13-2~ubuntu18.04                                              amd64        X C Binding, record extension, development files
    ii  libxcb-render-util0:amd64                  0.3.9-1                                                         amd64        utility libraries for X C Binding -- render-util
    ii  libxcb-render-util0-dev:amd64              0.3.9-1                                                         amd64        utility libraries for X C Binding -- render-util
    ii  libxcb-render0:amd64                       1.13-2~ubuntu18.04                                              amd64        X C Binding, render extension
    ii  libxcb-render0-dev:amd64                   1.13-2~ubuntu18.04                                              amd64        X C Binding, render extension, development files
    ii  libxcb-res0:amd64                          1.13-2~ubuntu18.04                                              amd64        X C Binding, res extension
    ii  libxcb-res0-dev:amd64                      1.13-2~ubuntu18.04                                              amd64        X C Binding, res extension, development files
    ii  libxcb-screensaver0:amd64                  1.13-2~ubuntu18.04                                              amd64        X C Binding, screensaver extension
    ii  libxcb-screensaver0-dev:amd64              1.13-2~ubuntu18.04                                              amd64        X C Binding, screensaver extension, development files
    ii  libxcb-shape0:amd64                        1.13-2~ubuntu18.04                                              amd64        X C Binding, shape extension
    ii  libxcb-shape0-dev:amd64                    1.13-2~ubuntu18.04                                              amd64        X C Binding, shape extension, development files
    ii  libxcb-shm0:amd64                          1.13-2~ubuntu18.04                                              amd64        X C Binding, shm extension
    ii  libxcb-shm0-dev:amd64                      1.13-2~ubuntu18.04                                              amd64        X C Binding, shm extension, development files
    ii  libxcb-sync-dev:amd64                      1.13-2~ubuntu18.04                                              amd64        X C Binding, sync extension, development files
    ii  libxcb-sync1:amd64                         1.13-2~ubuntu18.04                                              amd64        X C Binding, sync extension
    ii  libxcb-util-dev:amd64                      0.4.0-0ubuntu3                                                  amd64        utility libraries for X C Binding -- atom, aux and event
    ii  libxcb-util0-dev:amd64                     0.4.0-0ubuntu3                                                  amd64        dummy transitional package for utility libraries for X C Binding -- atom, aux and event
    ii  libxcb-util1:amd64                         0.4.0-0ubuntu3                                                  amd64        utility libraries for X C Binding -- atom, aux and event
    ii  libxcb-xf86dri0:amd64                      1.13-2~ubuntu18.04                                              amd64        X C Binding, xf86dri extension
    ii  libxcb-xf86dri0-dev:amd64                  1.13-2~ubuntu18.04                                              amd64        X C Binding, xf86dri extension, development files
    ii  libxcb-xfixes0:amd64                       1.13-2~ubuntu18.04                                              amd64        X C Binding, xfixes extension
    ii  libxcb-xfixes0-dev:amd64                   1.13-2~ubuntu18.04                                              amd64        X C Binding, xfixes extension, development files
    ii  libxcb-xinerama0:amd64                     1.13-2~ubuntu18.04                                              amd64        X C Binding, xinerama extension
    ii  libxcb-xinerama0-dev:amd64                 1.13-2~ubuntu18.04                                              amd64        X C Binding, xinerama extension, development files
    ii  libxcb-xinput-dev:amd64                    1.13-2~ubuntu18.04                                              amd64        X C Binding, xinput extension, development files
    ii  libxcb-xinput0:amd64                       1.13-2~ubuntu18.04                                              amd64        X C Binding, xinput extension
    ii  libxcb-xkb-dev:amd64                       1.13-2~ubuntu18.04                                              amd64        X C Binding, XKEYBOARD extension, development files
    ii  libxcb-xkb1:amd64                          1.13-2~ubuntu18.04                                              amd64        X C Binding, XKEYBOARD extension
    ii  libxcb-xrm-dev:amd64                       1.0-3                                                           amd64        utility functions for the X resource manager, development files
    ii  libxcb-xrm0:amd64                          1.0-3                                                           amd64        utility functions for the X resource manager
    ii  libxcb-xtest0:amd64                        1.13-2~ubuntu18.04                                              amd64        X C Binding, xtest extension
    ii  libxcb-xtest0-dev:amd64                    1.13-2~ubuntu18.04                                              amd64        X C Binding, xtest extension, development files
    ii  libxcb-xv0:amd64                           1.13-2~ubuntu18.04                                              amd64        X C Binding, xv extension
    ii  libxcb-xv0-dev:amd64                       1.13-2~ubuntu18.04                                              amd64        X C Binding, xv extension, development files
    ii  libxcb-xvmc0:amd64                         1.13-2~ubuntu18.04                                              amd64        X C Binding, xvmc extension
    ii  libxcb-xvmc0-dev:amd64                     1.13-2~ubuntu18.04                                              amd64        X C Binding, xvmc extension, development files
    ii  libxcb1:amd64                              1.13-2~ubuntu18.04                                              amd64        X C Binding
    ii  libxcb1-dev:amd64                          1.13-2~ubuntu18.04                                              amd64        X C Binding, development files
    ➜  ~ dpkg -la | grep xkbcommon         
    ii  libxkbcommon-dev:amd64                     0.8.2-1~ubuntu18.04.1                                           amd64        library interface to the XKB compiler - development files
    ii  libxkbcommon-x11-0:amd64                   0.8.2-1~ubuntu18.04.1                                           amd64        library to create keymaps with the XKB X11 protocol
    ii  libxkbcommon-x11-dev:amd64                 0.8.2-1~ubuntu18.04.1                                           amd64        library to create keymaps with the XKB X11 protocol - development files
    ii  libxkbcommon0:amd64                        0.8.2-1~ubuntu18.04.1                                           amd64        library interface to the XKB compiler - shared library
    
    

    And in the output of configure, all is found:

    -- Found XCB: /usr/lib/x86_64-linux-gnu/libxcb.so;/usr/lib/x86_64-linux-gnu/libxcb-render.so;/usr/lib/x86_64-linux-gnu/libxcb-shape.so;/usr/lib/x86_64-linux-gnu/libxcb-xfixes.so;/usr/lib/x86_64-linux-gnu/libxcb-shm.so;/usr/lib/x86_64-linux-gnu/libxcb-util.so;/usr/lib/x86_64-linux-gnu/libxcb-composite.so;/usr/lib/x86_64-linux-gnu/libxcb-cursor.so;/usr/lib/x86_64-linux-gnu/libxcb-damage.so;/usr/lib/x86_64-linux-gnu/libxcb-dpms.so;/usr/lib/x86_64-linux-gnu/libxcb-dri2.so;/usr/lib/x86_64-linux-gnu/libxcb-dri3.so;/usr/lib/x86_64-linux-gnu/libxcb-ewmh.so;/usr/lib/x86_64-linux-gnu/libxcb-glx.so;/usr/lib/x86_64-linux-gnu/libxcb-icccm.so;/usr/lib/x86_64-linux-gnu/libxcb-image.so;/usr/lib/x86_64-linux-gnu/libxcb-keysyms.so;/usr/lib/x86_64-linux-gnu/libxcb-present.so;/usr/lib/x86_64-linux-gnu/libxcb-randr.so;/usr/lib/x86_64-linux-gnu/libxcb-record.so;/usr/lib/x86_64-linux-gnu/libxcb-render-util.so;/usr/lib/x86_64-linux-gnu/libxcb-res.so;/usr/lib/x86_64-linux-gnu/libxcb-screensaver.so;/usr/lib/x86_64-linux-gnu/libxcb-sync.so;/usr/lib/x86_64-linux-gnu/libxcb-xf86dri.so;/usr/lib/x86_64-linux-gnu/libxcb-xinerama.so;/usr/lib/x86_64-linux-gnu/libxcb-xkb.so;/usr/lib/x86_64-linux-gnu/libxcb-xtest.so;/usr/lib/x86_64-linux-gnu/libxcb-xv.so;/usr/lib/x86_64-linux-gnu/libxcb-xvmc.so;/usr/lib/x86_64-linux-gnu/libxcb-xinput.so (found suitable version "1.13", minimum required is "1.12") found components: XINPUT 
    -- Checking for module 'xkbcommon-x11>=0.4.1'
    --   Found xkbcommon-x11, version 0.8.2
    -- Running syncqt for module: 'QtOpenGL' 
    -- Running syncqt for module: 'QtWidgets' 
    -- Checking for module 'gtk+-3.0 >= 3.6'
    --   Found gtk+-3.0 , version 3.22.30
    -- Running syncqt for module: 'QtOpenGLWidgets' 
    -- Running syncqt for module: 'QtDeviceDiscoverySupport' 
    -- Running syncqt for module: 'QtFbSupport' 
    -- Could NOT find Libinput (missing: Libinput_LIBRARY Libinput_INCLUDE_DIR) 
    -- Found XKB: /usr/lib/x86_64-linux-gnu/libxkbcommon.so (found version "0.8.2") 
    ...
    -- Found XKB: /usr/lib/x86_64-linux-gnu/libxkbcommon.so (found suitable version "0.8.2", minimum required is "0.5.0") 
    ...
    

    I don't know what is blocking it.


  • Lifetime Qt Champion

    Then as I suggested: read the configuration test log files.



  • @SGaist said in Built Qt6 from sources, problem with xcb plugin:

    Then as I suggested: read the configuration test log files.

    I am sorry, where is that file? I see not log files in build dir.


  • Lifetime Qt Champion

    Don't you have some CMakeError.log files around ?



  • The compilation has no errors, the problem is that platform plugin for xcb is not generated.

    ➜  build ls -al
    total 37248
    drwxr-xr-x 17 mnesarco mnesarco     4096 Dec  2 14:26 .
    drwxrwxr-x  5 mnesarco mnesarco     4096 Dec  2 11:50 ..
    -rw-r--r--  1 mnesarco mnesarco 18076483 Dec  2 14:26 build.ninja
    -rw-r--r--  1 mnesarco mnesarco   320652 Dec  2 14:26 CMakeCache.txt
    drwxr-xr-x  4 mnesarco mnesarco     4096 Dec  2 14:26 CMakeFiles
    -rw-r--r--  1 mnesarco mnesarco     4430 Dec  2 13:19 cmake_install.cmake
    -rw-r--r--  1 mnesarco mnesarco      129 Dec  2 14:26 config.opt
    drwxr-xr-x  4 mnesarco mnesarco     4096 Dec  2 11:55 config.tests
    -rw-r--r--  1 mnesarco mnesarco      633 Dec  2 12:56 CTestTestfile.cmake
    -rw-r--r--  1 mnesarco mnesarco   977889 Dec  2 12:25 install_manifest.txt
    -rw-r--r--  1 mnesarco mnesarco 17585308 Dec  2 14:35 .ninja_deps
    -rw-r--r--  1 mnesarco mnesarco  1082507 Dec  2 14:35 .ninja_log
    drwxr-xr-x  4 mnesarco mnesarco     4096 Dec  2 14:26 qt5compat
    drwxr-xr-x 14 mnesarco mnesarco     4096 Dec  2 14:26 qtbase
    drwxr-xr-x  5 mnesarco mnesarco     4096 Dec  2 14:26 qtdeclarative
    drwxr-xr-x  4 mnesarco mnesarco     4096 Dec  2 14:26 qtdoc
    drwxr-xr-x  3 mnesarco mnesarco     4096 Dec  2 14:26 qtqa
    drwxr-xr-x  5 mnesarco mnesarco     4096 Dec  2 14:26 qtquick3d
    drwxr-xr-x  4 mnesarco mnesarco     4096 Dec  2 14:26 qtquickcontrols2
    drwxr-xr-x  4 mnesarco mnesarco     4096 Dec  2 14:26 qtquicktimeline
    drwxr-xr-x  5 mnesarco mnesarco     4096 Dec  2 14:26 qtshadertools
    drwxr-xr-x  4 mnesarco mnesarco     4096 Dec  2 14:26 qtsvg
    drwxr-xr-x  4 mnesarco mnesarco     4096 Dec  2 14:26 qttools
    drwxr-xr-x  4 mnesarco mnesarco     4096 Dec  2 14:26 qttranslations
    drwxr-xr-x  4 mnesarco mnesarco     4096 Dec  2 12:00 qtwaylan
    

  • Lifetime Qt Champion

    @mnesarco said in Built Qt6 from sources, problem with xcb plugin:

    XCB Xlib ............................. no

    Apart from what you're saying but it looks like some of the required xcb stuff is not found.



  • @Christian-Ehrlicher It is obvious, some xcb stuff is not found, the question is what. Because ./configure reports a lot of crap like this:

    -- Found XCB: /usr/lib/x86_64-linux-gnu/libxcb.so;/usr/lib/x86_64-lin...
    


  • I have found CMakeError.log and CMakeOutput.log, they have a lot of things but nothing related with xcb.


  • Lifetime Qt Champion

    According to the config file XCB xlib needs:

            "xcb_xlib": {
                "label": "XCB Xlib",
                "test": {
                    "main": "(void) XGetXCBConnection((Display *)0);"
                },
                "headers": "X11/Xlib-xcb.h",
                "sources": [
                    { "type": "pkgConfig", "args": "x11-xcb" },
                    "-lX11-xcb"
                ],
                "use": "xcb xlib"
    


  • It is installed:

    ➜  qtbase dpkg -la | grep Xlib
    ii  libx11-xcb-dev:amd64                       2:1.6.4-3ubuntu0.3                                              amd64        Xlib/XCB interface library (development headers)
    ii  libx11-xcb1:amd64                          2:1.6.4-3ubuntu0.3                                              amd64        Xlib/XCB interface library
    
    

  • Lifetime Qt Champion

    Try to search for some output of those values inside CMakeFiles subdir and try to compile this

    #include <X11/Xlib-xcb.h>
    
    int main(int, char**)
    {
      (void) XGetXCBConnection((Display *)0);
      return 0;
    }
    

    g++ main.cpp -lX11-xcb



  • @Christian-Ehrlicher said in Built Qt6 from sources, problem with xcb plugin:

    #include <X11/Xlib-xcb.h>

    int main(int, char**)
    {
    (void) XGetXCBConnection((Display *)0);
    return 0;
    }

    ➜  test99 vi test.cpp 
    ➜  test99 c++ test.cpp -lX11-xcb
    ➜  test99 ./a.out 
    [1]    12914 segmentation fault (core dumped)  ./a.out
    ➜  test99 
    It compiles, but segfault on run.
    

  • Lifetime Qt Champion

    Doesn't matter that it does not execute - cmake only checks if it compiles and links. Sorry you have to dig though the CMakeFiles directory.



  • Apparently it was some kind of cache problem. Because I deleted the build folder, opened a new terminal a build from scratch and:

    Features used by QPA backends:
      evdev .................................. yes
      libinput ............................... yes
      INTEGRITY HID .......................... no
      mtdev .................................. yes
      tslib .................................. no
      xkbcommon .............................. yes
      X11 specific:
        XLib ................................. yes
        XCB Xlib ............................. yes
        EGL on X11 ........................... yes
        xkbcommon-x11 ........................ yes
    QPA backends:
      DirectFB ............................... no
      EGLFS .................................. yes
      EGLFS details:
        EGLFS OpenWFD ........................ no
        EGLFS i.Mx6 .......................... no
        EGLFS i.Mx6 Wayland .................. no
        EGLFS RCAR ........................... no
        EGLFS EGLDevice ...................... yes
        EGLFS GBM ............................ no
        EGLFS VSP2 ........................... no
        EGLFS Mali ........................... no
        EGLFS Raspberry Pi ................... no
        EGLFS X11 ............................ yes
      LinuxFB ................................ yes
      VNC .................................... yes
      QNX:
        lgmon ................................ no
        IMF .................................. no
      XCB:
        Using system-provided xcb-xinput ..... yes
        Native painting (experimental) ....... no
        GL integrations:
          GLX Plugin ......................... yes
            XCB GLX .......................... yes
          EGL-X11 Plugin ..................... yes
      Windows:
        Direct 2D ............................ no
        Direct 2D 1.1 ........................ no
        DirectWrite .......................... no
        DirectWrite 3 ........................ no
    
    

    It is building, so I will report if succeed.



  • I can confirm that it worked. So which was exactly the missing dependency I don't know. But after installing all the mentioned libraries and build from scratch on an empty build directory, it worked.


  • Lifetime Qt Champion

    As the configure scripts prints at the end: if you re-run configure, you have to clean first. Otherwise you may have leftovers from your previous configure/build attempt that will make it so that not all tests are rerun.


Log in to reply