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

[drunk_solder]

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)
root@FriendlyELEC:/usr/local/qt_sdk/examples/gui/analogclock# 

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=$QTDIR/plugins/platforms
export LD_LIBRARY_PATH=$QTDIR/lib:$LD_LIBRARY_PATH
#export LD_LIBRARY_PATH=/usr/lib/arm-linux-gnueabihf/:$LD_LIBRARY_PATH
export QT_QPA_PLATFORM=linuxfb:fb=/dev/fb0:size=800x600:mmSize=800x600:offset=0xx
0:tty=/dev/tty1
#framebuffer
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
libqlinuxfb.so  libqminimal.so  libqoffscreen.so  libqxcb.so

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
/usr/lib/arm-linux-gnueabihf/pkgconfig

This is what I used for cross compiling QT:

#!/bin/sh
./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?

[SGaist]

Hi and welcome to devnet,

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