How to configure Qt on BBB with linux

AXZS

I came across the bug
QTBUG72399 : Qt 5.12 build breaks with gcc 4.8 compiler.

is there any other way to cross compile Qt with BBB?
like trying another version or another toolchain?

SGaist

Aren't you using a release 7 series of GCC ?

AXZS

yes, I have tried both with GCC 7.5 and GCC 4, but still not able to cross compile.
The error of std :num limits is resolved by including header file #include<limits> .

But, still, some plugin errors of qtquicktimeline error is popping.

SGaist

I would limit the module compilation to just the list of the ones you need.

AXZS

Hi,

Thanks for your support .

Qt has configured successfully with command

./configure -opensource -confirm-license -platform qws/linux-x86-g++ -xplatform qws/linux-am335x-g++ -no-sse2 -no-ssse3 -no-glib -no-cups -no-accessibility -no-openssl -no-pch -no-sql-ibase -no-sql-odbc -no-sql-psql -no-sql-sqlite -nomake examples

..
Proceeding to make command ,errors are popping as follows-
qt-everywhere-src-6.0.4/qtbase/src/corelib/global/qglobal.cpp:2335:2: error: ‘QString’ does not name a type
2335 | QString QSysInfo::buildCpuArchitecture()

I have tried the solutions provided on supported platforms to include few header files in qglobal.cpp file, but it is still the same lists of errors .
What may be the possible procedure?

SGaist

What if you drop the no-pch option ?
One that you should add is the nomake tests.

AXZS

@SGaist
Hi,

after dropping no-make tests, command ./configure was executed but further steps were not running.
I tried to build and run Qtproject on AM625x EVM board by installing AM625x SDK and following steps as per TI_ SDK with making dynamically executable file.
Compiling and running Qt project was successful on AM625x EVM board.

2.But, again when I tried my luck on Beaglebone with same procedure, i.e installation of AM335x SDK and running, with same installed Qt5.7.0, output of command file freshly built qtproject is as follows:

Qtproject: ELF 32-bit LSB executable, ARM, EABI5 version 1 (SYSV), dynamically linked, interpreter /lib/ld-linux-armhf.so.3, for GNU/Linux 3.2.0, with debug_info, not stripped

This command is producing output in AM625x EVM as follows-

Qtproject: ELF 32-bit LSB executable, ARM, version 1 (SYSV), dynamically linked (uses shared libs), for GNU/Linux 2.6.31, BuildID[sha1]=0x8569a0956d8efffcfde68fca5c883be5fa4f1c31, not stripped

When running ./Qtproject on beaglebone board,
The error is popping as:
error while loading shared libraries: libQt5Quick.so.5.so: cannot open shared object file: No such file or directory

I came across thread
https://forum.qt.io/topic/58963/error-while-loading-shared-libraries-cannot-open-shared-object-file-no-such-file-or-directory
and tried QMAKE_LFLAGS += -Wl,-rpath,"'$$ORIGIN'" in .pro file of Qtproject, but the file is still not being made as dynamically executable with shared libraries.

Please guide.

SGaist

Do you have the Qt libraries deployed on your target ?
If so, where ?

AXZS

yes , Qt is installed on target.
root@beaglebone:~$ qmake --version
** QMake version 3.1**
** Using Qt version 5.11.3 in /usr/lib/arm-linux-gnueabihf

But,I am not sure that all libraries are installed.
Still,error is
libQt5QmlModels.so.5 not found, could'nt find any package by glob or regex.

AXZS

I have connected LCD display to beaglebone and also tried below commands from link https://elinux.org/BeagleBoneBlack/SGX_%2B_Qt_EGLFS_%2B_Weston#QtQuick_.2B_EGLFS

apt-get install libqt5qml5 qml-module-qtquick-controls qt5-default qtdeclarative5-dev qtquickcontrols5-examples
cd /usr/lib/arm-linux-gnueabihf/qt5/examples/quickcontrols/extras/dashboard
qmake
make
export QT_QPA_PLATFORM=eglfs
export QT_QPA_EGLFS_INTEGRATION=none
./dashboard

But getting error
EGLFS:failed to open /dev/fb0
EGLFS:can't continue without display

AXZS

Hi,
I installed libraries
sudo apt-get -y install build-essential openssl libssl-dev libssl1.0 libgl1-mesa-dev libqt5x11extras5

and tried to run

cd /usr/lib/arm-linux-gnueabihf/qt5/examples/quickcontrols/extras/dashboard
qmake
make
export QT_QPA_PLATFORM=eglfs
export QT_QPA_EGLFS_INTEGRATION=none
./dashboard*

Now error is
qt.qpa.screen QXcbconnection:Could not connect to display

XDG_SESSION_TYPE is x11

What could be possible error?

SGaist

Are you doing that on the BBB directly ?
Do you have any graphical interface running ?
Which plugins do you have installed with the package manager ?

AXZS

Hi,
I am trying to run "Hello world" made on Qt ,developed on host PC and then copying it to beaglebone using scp command.
The beaglebone is showing directory with executable file of "hello world" but when ./helloworld command is run, the error is shown.

I have installed qt5-qtdeclarative5.15 on host PC.
Same error of libqt5qmlmodels.so.5 shared libraries not found.
Do I need to install it on beaglebone also ?If so, please guide with all required plugins,packages and dependencies of Qt supported .

SGaist

Since you cross-compiled Qt, you should deploy that one on your board.

If you want to stay with the distribution provided Qt of your target, you need to install all the Qt packages you are using in your application.

AXZS

Hi,
Thanks for all support.
Finally, cross-compilation of beaglebone with Qt done.
But, still ,
next stone in the path is -
https://forum.qt.io/topic/124754/remote-generic-linux-device

Please guide, what statement to add install in Cmakelists.txt file