Create embedded QT Gui applications for a Bananapi-M2-Zero

lo38230

I have QT 5.12 and I cannot select it in QT creator Kits because it always says that the compiler I downloaded installed and selected g++-arm-gnueabihf 32 bits compatible with the Banana PI M2 zero cannot produce code for this QT version. This is the same for all earlyer versions of QT I downloaded on https://download.qt.io/archive/qt By version 5.1.1 it is possible to have a 32 bit version installer qt-linux-opensource-5.1.1-x86-offline.run The installer doesn't work at the moment, there is an error that I didn't solve at the moment:
error while loading shared libraries: libSM.so.6: cannot open shared object file: No such file or directory
This installer look like QT 5.9.9 64 bits that I could install and with an already existing builded qmake for specific architecture(X86). Perhaps it is not important at this step. I would be able to select QT5.1.1 in the Qt creator kit selector and give my arm-gnueabihf architecture in my self created qmake.conf path. Not shure it will work, this installed qt doesnt contain a configure executable like the downloaded qt-everywhere-opensource-src-4.6.3. I will try to generate qmake by using "./configure" in "qt-everywhere-opensource-src-5.1.0.tar.gz" . May be I will have to configure something manually like 32 bits selector and Im not sure at the moment it will success.
Otherwise I think about using an arm-gnueabihf 64 bits compiler if it exists to use with QT 5.12 but im not sure it will work on my Banana Pi M2 zero on which I installed and updated ubuntu MATE 18.04 LTS

uname -i

gives

armv7l

getconf LONG_BIT

gives

32

SGaist

Did you saw this guide ?

lo38230

It seems to work.

After the command make I get the error :

ssl/qsslcertificate_openssl.cpp:63:30: error: invalid use of incomplete type ‘X509’ {aka ‘struct x509_st’}
63 | return qHashBits(x509->sha1_hash, SHA_DIGEST_LENGTH, seed);

I'm not sure if I have to install a previous compatible version of libssl1.0 for armhf.

SGaist

Which version of Qt are you building exactly now ?
Which exact version of OpenSSL do you have at hand for your target ?

lo38230

It is qt-everywhere-opensource-src-5.5.1 according to your adviced website, I substituted gnueabi by gnueabihf.
By default on my PC Ubuntu 20 64 bits is this single file called:
/usr/bin/openssl : ELF 64-bit LSB shared object, x86-64, version 1 (SYSV), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, BuildID[sha1]=4d2003d01494e5fd39293fdc8379c406d6b641b2, for GNU/Linux 3.2.0, stripped

Otherwise I have this old version file used by an old system (not arm) with qt 4.8
... /platform/sysroot-target/usr/bin/openssl: ELF 32-bit LSB executable, Intel 80386, version 1 (SYSV), dynamically linked, interpreter /lib/ld-linux.so.2, for GNU/Linux 2.6.23, with debug_info, not stripped

A few month ago I compiled the operating system Ubuntu MATE image (BPI-M2P-bsp-4.4) for my BananaPi M2 zero. It was successful and it actually works. I remember I had to create
/usr/lib/arm-liunx-gnueabihf and put some things into manually regarding the error messages. The compilation of Qt seems to use this folder too. In this folder there is
/usr/lib/arm-linux-gnueabihf/openssl-1.0.0/engines
with
lib4758cca.so
libaep.so
libatalla.so
libcapi.so
libchil.so
libcswift.so
libgmp.so
libgost.so
libnuron.so
libpadlock.so
libsureware.so
libubsec.so

In the package for the os compilation there is

... /BPI-M2P-bsp-4.4/sunxi-pack/pctools/linux/openssl
containing:
create_toc0
dragonsecboot
genrsa
rec
rsa
x509

there is a sourcecode three in:
... /BPI-M2P-bsp-4.4/u-boot-sunxi/lib/openssl

There is a library three in another operating system package (BPI-M2Z) that I could not compile
... /BPI-M2Z/sysroot/usr/lib/arm-linux-gnueabihf/openssl-1.0.0/
a single library
... /BPI-M2Z/sysroot/usr/lib/arm-linux-gnueabihf/ruby/2.5.0/openssl.so
some pyton sourcecodes in
... /BPI-M2Z/sysroot/usr/lib/python3/dist-packages/cryptography/hazmat/backends/openssl
some ruby files in
... /BPI-M2Z/sysroot/usr/lib/ruby/2.5.0/openssl
and the same three
... /BPI-M2Z-bsp/sunxi-pack/pctools/linux/openssl as in the BPI-M2P-bsp-4.4 package

Perhaps I need to create a link to the os package libraries.

I downloaded those packages:
libssl1.0-dev_1.0.2u-1~deb9u1_armhf.deb
libssl1.0.2-udeb_1.0.2u-1~deb9u1_armhf.udeb
libssl1.0-dev_1.0.2n-1ubuntu5.3_armhf.deb
but the installation fails due to dependancy.

I downloaded
openssl-1.0.2k.tar.gz
which contains a configure executable, I didnt try to compile it at the moment.

SGaist

Just because the guide mentions 5.5.1, you shouldn't just go blindly with it. Use a recent version of Qt. This one is not supported anymore.

lo38230

I downloaded from

https://ftp.osuosl.org/pub/blfs/conglomeration/qt5/

the package

qt-everywhere-src-5.14.2

containing a configure executable

I copied
/qtbase/mkspecs/linux-arm-gnueabi-g++/
to
/qtbase/mkspecs/linux-arm-gnueabihf-g++/
according to my architecture, and adapted qmake.conf wihth armgnueabi->armgnueabihf
The command line:
./configure -release -opensource -xplatform linux-arm-gnueabihf-g++ -prefix /opt/qt5-arm -no-opengl
x11 option removed because not supported.
At the end of the long make there is an error
libz.so.1, required by /home/eric/qt-everywhere-src-5.14.2/qtbase/lib/libQt5Gui.so not found. I have it on my computer at several places:
/usr/lib/i386-linux-gnu/libz.so.1
/usr/lib/x86_64-linux-gnu/libz.so.1
/usr/lib32/libz.so.1
How do I specify wich to use?
Is it in the command line? in qmake.conf? in path? perform a ln -s?

SGaist

It should be available from your device sysroot.

lo38230

I solved this problem by adding
QMAKE_LIBS += -lz
in my qmake.conf.

But now I have :
sh: 1: python: not found
Project ERROR: Building QtQml requires Python.
make: *** [Makefile:340: module-qtdeclarative-make_first] Error 3

python is already installed on my computer.

SGaist

Which version of Python ?

lo38230

python3 -V

gives

Python 3.8.2

...

ok solved by

sudo ln -s python3 python

in /usr/bin

...

next error is:
Project ERROR: Unknown module(s) in QT: openglextensions
make[2]: *** [Makefile:96: sub-render-make_first-ordered] Error 3

SGaist

QtQuick requires OpenGL but you disabled it.

lo38230

Make for QT 5 arm successful
Make install successful

I create a new basic application Qt 5.14.2 Widgets. Ok With default kit.

When I select arm-linux-gnueabihf I have some compile errors:

/opt/qt5-arm/include/QtCore/qbasicatomic.h:61:4: error: #error "Qt requires C++11 support"

/opt/qt5-arm/include/QtCore/qbasicatomic.h:97:23: error: ‘QAtomicOpsSupport’ was not declared in this scope

/opt/qt5-arm/include/QtCore/qbasicatomic.h:99:14: error: ‘Ops’ has not been declared

/opt/qt5-arm/include/QtCore/qbasicatomic.h:238:13: error: ‘QAtomicOps’ does not name a type

/opt/qt5-arm/include/QtCore/qbasicatomic.h:97:51: error: ‘::IsSupported’ has not been declared

SGaist

Did you properly create a kit using your cross-compiled Qt ?

lo38230

Yes , I added my cross compiled(I remember I had to remove the -no-c++11 of ./configure command because it was not recognized) QT Version Qt 5.14.2(qt5-arm) /opt/qt5-arm/bin/qmake in Qc Kits and it is accepted.
I added the compilers with the package you give me:
gcc Linaro
/home/eric/gcc-linaro-arm-linux-gnueabihf-4.9-2014.07_linux/bin/arm-linux-gnueabihf-gcc
g++ Linaro
/home/eric/gcc-linaro-arm-linux-gnueabihf-4.9-2014.07_linux/bin/arm-linux-gnueabihf-g++
I could not add the debugger arm-Debugger from your package
/home/eric/gcc-linaro-arm-linux-gnueabihf-4.9-2014.07_linux/bin/arm-linux-gnueabihf-gdb
It is not recognized by Qc. I selected GDB multiarch(/usr/bin/gdb-multiarch) which I already have.

Perhaps I should have version 5.14 of compilers and debugger?

As device I have generic Linux device, Qt mkspec is empty.
How should I configure the separated device BananaPi M2 Zero connected trough Ethernet with address 192.168.1.110 to my development PC with Ubuntu Linux? Should I create something else as generic Linux Device?

...

Problem solved by selecting most recent compilers.