QMYSQL driver not loaded - cross compiling for Raspberry PI 3

[JarekT]

@jsulm I've extracted again the sources. But I'm not sure if I understand what you meant by: "To avoid this do out of source builds". Do you mean that after I have newly extracted source code, I should always do the qmake in a new folder (eg. "build" as you mentioned) so that I do not affect the source code and in this way I can always do fresh compilation without the need to extract the source code files again?

Assuming that this is what you meant I did this:

As I can see mysql was not compiled... Could you please check if the paths and prefixes are correct?...

[jsulm]

@JarekT said in QMYSQL driver not loaded - cross compiling for Raspberry PI 3:

I should always do the qmake in a new folder

Yes.

To check why it still does not work please see what is in configure.log file.

[JarekT]

@jsulm Here is what I have in the config.log (I'm showing here only the part that contains information about the failures)

Could you please help me understand those problems?

[KroMignon]

@JarekT said in QMYSQL driver not loaded - cross compiling for Raspberry PI 3:

Could you please help me understand those problems?

Can you says which is the local path where you have put the sysroot? I supposed it was /home/embsys/raspi/sysroot.
Then search in this path where is located libmysqlclient with find:

find /home/embsys/raspi/sysroot -name libmysqlclient*.*

Then use the path to configure/compile your plugin:

/home/embsys/raspi/qtbase/bin/qmake -- MYSQL_PREFIX=<lib_mysqlclient_path>

[JarekT]

@KroMignon said in QMYSQL driver not loaded - cross compiling for Raspberry PI 3:

Can you says which is the local path where you have put the sysroot? I supposed it was /home/embsys/raspi/sysroot.

Yes, this is my sysroot. I did it as you can see below

This command I tried also before and the results are unsuccessful as before..
Here I'm configuring/compiling the plugin using sqldriver.pro file, but I also read somewhere that mysql.pro (/home/embsys/raspi/qt-everywhere-src-5.12.3/qtbase/src/plugins/sqldrivers/mysql/mysql.pro) file should compiled. Do you know anything about it?

[JarekT]

Another idea: shouldn't I configure qmake itself before I try to use it to compile the plugin?

That was my configure command when I was doing cross-compiling configuration (as in the LINK)

./configure -release -opengl es2 -device linux-rasp-pi3-g++ -device-option CROSS_COMPILE=~/raspi/tools/arm-bcm2708/gcc-linaro-arm-linux-gnueabihf-raspbian-x64/bin/arm-linux-gnueabihf- -sysroot ~/raspi/sysroot -opensource -confirm-license -make libs -prefix /usr/local/qt5pi -extprefix ~/raspi/qt5pi -hostprefix ~/raspi/qt5 -no-use-gold-linker -v -no-gbm

The above doesn't include mysql feature (should it??)

[jsulm]

@JarekT said in QMYSQL driver not loaded - cross compiling for Raspberry PI 3:

shouldn't I configure qmake itself

What do you want to configure?

[JarekT]

@jsulm Sorry if the way I explained it was not correct. I meant that when I was preparing the framework for cross-compilation in the folder /home/embsys/raspi/qtbase I did

./configure -release -opengl es2 -device linux-rasp-pi3-g++ -device-option CROSS_COMPILE=~/raspi/tools/arm-bcm2708/gcc-linaro-arm-linux-gnueabihf-raspbian-x64/bin/arm-linux-gnueabihf- -sysroot ~/raspi/sysroot -opensource -confirm-license -make libs -prefix /usr/local/qt5pi -extprefix ~/raspi/qt5pi -hostprefix ~/raspi/qt5 -no-use-gold-linker -v -no-gbm

Should it contain something about mysql?

[jsulm]

@JarekT said in QMYSQL driver not loaded - cross compiling for Raspberry PI 3:

Should it contain something about mysql?

It should be possible to build MySQL related stuff after compiling Qt.

Did you search for libmysqlclient* as @KroMignon suggested to make sure you pass correct paths?

Also, please post text instead of screen-shots.

[JarekT]

@jsulm said in QMYSQL driver not loaded - cross compiling for Raspberry PI 3:

Did you search for libmysqlclient* as @KroMignon suggested to make sure you pass correct paths?

Yes, the paths for libmysqlclient.. is correct.

embsys@JT-UBUNTU:~/qmakeBuild$ find /home/embsys/raspi/sysroot -name libmysqlclient*.*
/home/embsys/raspi/sysroot/usr/lib/arm-linux-gnueabihf/libmysqlclient.a
/home/embsys/raspi/sysroot/usr/lib/arm-linux-gnueabihf/libmysqlclient_r.so
/home/embsys/raspi/sysroot/usr/lib/arm-linux-gnueabihf/libmysqlclient.so
/home/embsys/raspi/sysroot/usr/lib/arm-linux-gnueabihf/libmysqlclient_r.a

Ok, I will try to post text instead of screen-shots.

[JarekT]

I'm constantly trying to solve the issue... any help would be much appreciated..

I have noticed that when I choose different qmake, MySQL plugin is configured and prepared for building. Please have a look:

embsys@JT-UBUNTU:~/raspi/test$ /home/embsys/Qt5.14.2/5.14.2/gcc_64/bin/qmake /home/embsys/raspi/qt-everywhere-src-5.12.3/qtbase/src/plugins/sqldrivers/sqldrivers.pro -- MYSQL_PREFIX=/home/embsys/raspi/sysroot/usr/lib/arm-linux-gnueabihf

Running configuration tests...
Checking for DB2 (IBM)... no
Checking for InterBase... no
Checking for MySQL... yes
Checking for OCI (Oracle)... no
Checking for ODBC... no
Checking for PostgreSQL... yes
Checking for SQLite (version 2)... no
Checking for TDS (Sybase)... no
Done running configuration tests.

Configure summary:

Qt Sql Drivers:
  DB2 (IBM) .............................. no
  InterBase .............................. no
  MySql .................................. yes
  OCI (Oracle) ........................... no
  ODBC ................................... no
  PostgreSQL ............................. yes
  SQLite2 ................................ no
  SQLite ................................. yes
    Using system provided SQLite ......... no
  TDS (Sybase) ........................... no

Qt is now configured for building. Just run 'make'.
Once everything is built, you must run 'make install'.
Qt will be installed into '/home/embsys/Qt5.14.2/5.14.2/gcc_64'.

Prior to reconfiguration, make sure you remove any leftovers from
the previous build.

Unfortunately when I try to use the qmake for cross-compiler path I get the following:

embsys@JT-UBUNTU:~/raspi/test$ /home/embsys/raspi/qtbase/qmake/qmake /home/embsys/raspi/qt-everywhere-src-5.12.3/qtbase/src/plugins/sqldrivers/sqldrivers.pro -- MYSQL_PREFIX=/home/embsys/raspi/sysroot/usr/lib/arm-linux-gnueabihf

Running configuration tests...
Checking for DB2 (IBM)... no
Checking for InterBase... no
Checking for MySQL... no
Checking for OCI (Oracle)... no
Checking for ODBC... yes
Checking for PostgreSQL... yes
Checking for SQLite (version 2)... yes
Checking for TDS (Sybase)... yes
Done running configuration tests.

Configure summary:

Qt Sql Drivers:
  DB2 (IBM) .............................. no
  InterBase .............................. no
  MySql .................................. no
  OCI (Oracle) ........................... no
  ODBC ................................... yes
  PostgreSQL ............................. yes
  SQLite2 ................................ yes
  SQLite ................................. yes
    Using system provided SQLite ......... no
  TDS (Sybase) ........................... yes

Qt is now configured for building. Just run 'make'.
Once everything is built, you must run 'make install'.
Qt will be installed into '/home/embsys/raspi/qt5pi'.

Prior to reconfiguration, make sure you remove any leftovers from
the previous build.

I lack good knowledge about qmake tool, but maybe there is something wrong with the qmake I try to use for Raspberry PI.
BTW I have different qmakes in my host:

embsys@JT-UBUNTU:~/raspi$ sudo find / -name qmake -type f
/home/embsys/ti-processor-sdk-linux-rt-am335x-evm-05.03.00.07/linux-devkit/sysroots/x86_64-arago-linux/usr/bin/qt5/qmake
/home/embsys/ti-processor-sdk-linux-rt-am335x-evm-05.02.00.10/linux-devkit/sysroots/x86_64-arago-linux/usr/bin/qt5/qmake
/home/embsys/ti-processor-sdk-linux-am335x-evm-05.02.00.10/linux-devkit/sysroots/x86_64-arago-linux/usr/bin/qt5/qmake
/home/embsys/Qt5.14.2/qt-everywhere-src-5.14.2/qtbase/bin/qmake
/home/embsys/Qt5.14.2/5.14.2/gcc_64/bin/qmake
/home/embsys/raspi/qt5/bin/qmake
/home/embsys/raspi/qtbase/bin/qmake
/home/embsys/raspi/qtbase/qmake/qmake
find: ‘/run/user/1000/doc’: Permission denied
find: ‘/run/user/1000/gvfs’: Permission denied
/usr/lib/x86_64-linux-gnu/qt4/bin/qmake
/usr/lib/qt5/bin/qmake

Could sb explain what is the difference between those qmakes that are in RPi paths? namely:

/home/embsys/raspi/qt5/bin/qmake
/home/embsys/raspi/qtbase/bin/qmake
/home/embsys/raspi/qtbase/qmake/qmake

I tried all of them but they give the same results.

Is it possible that I somehow have a problem with Qt instalation for cross-compiling (and consequently with qmake) and this is the problem?

[JarekT]

Finally (!...) I was able to fix the problems. I'm showing the whole procedure, not only what relates to the main subject of this thread so that to contribute to the community..

I was using the following sites as a source information to work out the following solution: LINK1 (for other Qt/Raspberry PI configuration check: link), LINK2, LINK3, LINK4, LINK5, LINK6.

My hardware/software:

Host:
Ubuntu 18.04 (also I’ve check it on Ubuntu 20.04 and it also works)
Qt ver. 5.12.3 (I also tried 5.12.9, but it didn’t work, probably there was something wrong with the fix that needs to be done on the sources) - you can install the “sources” and all the modules you need from Qt Online Installer (link) because later on you can add/remove modules/versions easily by lauching ~/Qt/MaintenanceTool
QtCreator will be installed automatically (the newest version) when you use Qt Online Installer

Target:
Raspberry PI 3, with Raspbian Stretch

Procedure:

1. [on RPi] Edit sources list in /etc/apt/sources.list and uncomment the deb-src line:

sudo nano /etc/apt/sources.list

2. [on RPi] Update your system and install required libraries:

sudo apt-get update
sudo apt-get build-dep qt4-x11
sudo apt-get build-dep libqt5gui5
sudo apt-get install libudev-dev libinput-dev libts-dev libxcb-xinerama0-dev libxcb-xinerama0

After installing MySQL itself on RPi install also MySQL libraries/packages to be used by Qt:

sudo apt install mariadb-client libmariadb-dev-compat libqt5sql5-mysql

3. [on RPi] Prepare our target directory

sudo mkdir /usr/local/qt5pi
sudo chown pi:pi /usr/local/qt5pi

4. [on RPi] Correct links to EGL and GLES Drivers

sudo rm /usr/lib/arm-linux-gnueabihf/libEGL.so.1.0.0
sudo rm /usr/lib/arm-linux-gnueabihf/libGLESv2.so.2.0.0
sudo ln -s /opt/vc/lib/libbrcmEGL.so /usr/lib/arm-linux-gnueabihf/libEGL.so.1.0.0
sudo ln -s /opt/vc/lib/libbrcmGLESv2.so /usr/lib/arm-linux-gnueabihf/libGLESv2.so.2.0.0

5. [on host] Create our working directory and get a toolchain:

mkdir ~/raspi
cd ~/raspi
git clone https://github.com/raspberrypi/tools

6. [on host] Create a sysroot.

mkdir sysroot sysroot/usr sysroot/opt
rsync -avz pi@yourpi:/lib sysroot
rsync -avz pi@yourpi:/usr/include sysroot/usr
rsync -avz pi@yourpi:/usr/lib sysroot/usr
rsync -avz pi@yourpi:/opt/vc sysroot/opt

7. [on host] Adjust symlinks to be relative:

wget https://raw.githubusercontent.com/riscv/riscv-poky/master/scripts/sysroot-relativelinks.py
chmod +x sysroot-relativelinks.py
./sysroot-relativelinks.py sysroot

8. [on host] Modify the qmake.conf –> mkspecs/devices/linux-rasp-pi3-g++/qmake.conf

nano ~/raspi/qtbase/mkspecs/devices/linux-rasp-pi3-g++/qmake.conf

VC_LIBRARY_PATH = $$[QT_SYSROOT]/opt/vc/lib
VC_INCLUDE_PATH = $$[QT_SYSROOT]/opt/vc/include

VC_LINK_LINE = -L$${VC_LIBRARY_PATH}

QMAKE_LIBDIR_OPENGL_ES2 = $${VC_LIBRARY_PATH}
QMAKE_LIBDIR_EGL = $$QMAKE_LIBDIR_OPENGL_ES2
QMAKE_LIBDIR_OPENVG = $$QMAKE_LIBDIR_OPENGL_ES2

9. [on host] Protect your “sources” by creating working folder:

cd ~/Qt/5.12.3
tar jcvf qt-5.12.3-src.tar.bz2 Src
cd ~/raspi
tar xvf ~/Qt/5.12.3/qt-5.12.3-src.tar.bz2
mv Src qt-5.12.3-src

You can remove from qt-5.12.3-src the modules that you don’t want (at least for now) leaving qtbase folder - this will shorten the building process.
Create also working folder for the building (if building would be unsuccessful all you need to do is to delete the content of this folder and start again):

mkdir ~/raspi/build_raspi
cd ~/raspi/build_raspi

10. [on host] Configure
    From ~/raspi/build_raspi

../qt-5.12.3-src/configure -release -opengl es2 -device linux-rasp-pi3-g++ -device-option CROSS_COMPILE=~/raspi/tools/arm-bcm2708/gcc-linaro-arm-linux-gnueabihf-raspbian-x64/bin/arm-linux-gnueabihf- -sysroot ~/raspi/sysroot -opensource -confirm-license -make libs -prefix /usr/local/qt5pi -extprefix ~/raspi/qt5pi -hostprefix ~/raspi/qt5 -no-use-gold-linker -v -no-gbm -sql-mysql MYSQL_INCDIR=~/raspi/sysroot/usr/include/mysql MYSQL_LIBDIR=~/raspi/sysroot/usr/lib/arm-linux-gnueabihf

Notice the above contains also building MySQL driver.

Notice that the Config summary should contain (if it doesn't, you need to correct something... and do the configure again):
EGLFS Raspberry Pi ................... yes
MySql .................................. yes

Regarding “-release” parameter read here (in other words you don’t need “-debug-and-release” and the warnings you can ignore… at least this is what I can read at the forum).

10. [on host] Make
    From ~/raspi/build_raspi

make

You can use make -j 8 instead (much faster), but if there will be problems the all the “jobs” would need to finish and consequently it could be more difficult to find the error messages.

11. [on host] Make install
    From ~/raspi/build_raspi:

make install

12. [on host] Deploy Qt to the device. We simply sync everything from ~/raspi/qt5pi to the prefix we configured above
    From ~/raspi:

rsync -avz qt5pi pi@192.168.1.100:/usr/local

13. [on host] Configuration of QtCreator:

• Tools > Options > Devices > Add > Generic Linux Device > Start Wizard
• Write: “Raspberry” (your custom name), “192.168.X.X” (your Raspberry PI address), “pi” (your Raspberry PI user)
• Don’t write anything at “private key”, click “Next”
• There will be error window with: “Device test failed” > Cancel
• Authentication type → choose: “Default”
• Now test connection (“Test” button) and after you give the password to the RPi it should be successful
• Kits > Compilers > Add > GCC > C
• Write: “GCC (Raspberry Pi)” as your custom name and: “~/raspi/tools/arm-bcm2708/gcc-linaro-arm-linux-gnueabihf-raspbian-x64/bin/arm-linux-gnueabihf-gcc” as the path to the compiler
• Kits > Compilers > Add > GCC > C++
• Write: “G++ (Raspberry Pi)” as your custom name and: “~/raspi/tools/arm-bcm2708/gcc-linaro-arm-linux-gnueabihf-raspbian-x64/bin/arm-linux-gnueabihf-g++” as your path to the compiler
• Regarding the debugger, you should install:
  [On Host]:

sudo apt-get install gdb-multiarch

I’m not sure if this is needed but you can also install on RPi:

sudo apt-get install gdbserver

• Kits > Debuggers > Add
• Write: “GDB (Raspberry Pi)” as your custom name and “/usr/bin/gdb-multiarch” as the path to the debugger
• Apply
• Kits > Qt Version > Add
• Write path: ~/raspi/qt5/bin/qmake
• Write name: Qt %{Qt:Version} (qt5) Raspberry PI
• Apply
• Kits > Kits > Add
• Name: Raspi
• Device Type: Generic Linux Device
• The Device is the one created in the previous step
• We set the Sysroot to where we have the sysroot image: ~/raspi/sysroot
• Set compilers: "GCC (Raspberry PI)" and "G++ (Raspberry PI)"
• Set the Debugger to the one created previously
• Use the Qt version we created previously
• We don't need to set mkspec, so leave it empty.
• OK
• To enable your running application to have regular window do the following:
  Projects > Raspberry PI > Run > Environment > Batch Edit:

DISPLAY=:0.0
QT_QPA_PLATFORMTHEME=qt5ct
XAUTHORITY=/home/pi/.Xauthority
XDG_SESSION_TYPE=x11

If you don’t do this your application after starting up will be shown full screen but you will see it only when directly connect a screen to Raspberry PI (VNC desktop sharing will show nothing)
14) [on host] In your Raspberry PI project, in .pro file, you need to show where the executable file should be placed: (LINK):

target.path = /home/pi
INSTALLS += target

So comment the previous settings, eg.:

# qnx: target.path = /tmp/$${TARGET}/bin
# else: unix:!android: target.path = /opt/$${TARGET}/bin
# !isEmpty(target.path): INSTALLS += target

15. [on host] If you get: “WARNING: The code model could not parse a included file, which might lead to incorrect code completion and highlighting”:
    You need to deselect “ClangCodeModel” in HELP > ABOUT PLUGINS and restart QtCreator (LINK).
16. You should be able to build/run/debug your project on RPi and connect to the MySQL database without "QMYSQL driver not loaded" error.