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Error when Runnning Qt example on Arm Cortex-A9:could not find or load the Qt platform plugin "linuxfb"

  • Recently I've cross compiled QT 5.6 using arm-linux-gnueabihf in my ubuntu 14.04.And after I build up everything,I just mvoe it to the target board for a check.And things went unexpected when i run the analogclock:

    root@FriendlyELEC:/usr/local/qt_sdk/examples/gui/analogclock# ./analogclock 
    This application failed to start because it could not find or load the Qt platform plugin "linuxfb"
    in "/usr/local/qt_sdk/plugins/platforms".
    Available platform plugins are: linuxfb (from /usr/local/qt_sdk/plugins/platforms), minimal (from /usr/local/qt_sdk/plugins/platforms), offscreen (from /usr/local/qt_sdk/plugins/platforms).
    Reinstalling the application may fix this problem.
    Aborted (core dumped)

    It puzzled me because the system had found the .so files but unable to carry out.
    And it seems that my configuration is not to blame.This is part of my /etc/profile:

    export QTDIR=/usr/local/qt_sdk
    export QT_QPA_FONTDIR=$QTDIR/lib/fonts
    #export QT_PLUGIN_PATH=$QTDIR/plugins/platforms
    export QT_QPA_PLATFORM_PLUGIN_PATH=$QTDIR/plugins/platforms
    #export LD_LIBRARY_PATH=/usr/lib/arm-linux-gnueabihf/:$LD_LIBRARY_PATH
    export QT_QPA_PLATFORM=linuxfb:fb=/dev/fb0:size=800x600:mmSize=800x600:offset=0xx
    export QWS_MOUSE_PROTO=/dev/input/event0
    export QT_PLUGIN_PATH=$QTDIR/plugins/platforms/
    export PATH=$QTDIR/bin:$PATH

    And I also checked my directory:

    root@FriendlyELEC:/usr/local/qt_sdk# ls plugins/platforms

    And now I am wondering that maybe I got something wrong with my cross-compiling.Before I cross compiled the QT,I have set the env var PKG_CONFIG_LIBDIR:

    root@ming-2-00:~/qt-everywhere-opensource-src-5.6.0# echo $PKG_CONFIG_LIBDIR

    This is what I used for cross compiling QT:

    ./configure -prefix /opt/arm/qt5.6_64/qt_sdk \
    -opensource \
    -release \
    -no-pch \
    -confirm-license \
    -xplatform linux-arm-gnueabi-g++ \
    -shared \
    -qt-zlib \
    -iconv \
    -no-gif \
    -no-nis \
    -qt-libjpeg \
    -no-opengl \
    -no-cups \
    -no-glib \
    -no-dbus \
    -no-rpath \
    -no-sse2 -no-sse3 -no-ssse3 -no-sse4.1 -no-sse4.2 \
    -no-avx \
    -no-openssl \
    -nomake tools \
    -v \
    -qreal float \
    -qt-libpng \
    -qt-xcb \
    -make examples

    could anybody told me what's the mistake I shall fix?or what i miss?

  • Lifetime Qt Champion

    Hi and welcome to devnet,

    You should run ldd on the plugin to see if you have all dependencies installed on your device.

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