Building MySQL plugin via qmake and nmake (msvc17)

Hi all,

I want to create the mysql plugin from source using MariaDB and MSVC2017.

What have I done so far?

The MinGw Way (working)

I've copied the qtbase\src\plugins\sqldrivers\mysql\mysql.pro to mysql_edit.pro and commented out the following line :

QMAKE_USE += mysql

It's needed, because otherwise it still wants the native mysql sources. Which shouldn't happened at all, because you can't overwrite this flag through qmake via a minus or other "tricks":

qmake mysql.pro "QMAKE_USE -= mysql" //doesn't work
qmake "QMAKE_USE -= mysql" mysql.pro //doesn't work either
qmake mysql.pro "QMAKE_USE = " //nope

The error of not commenting out the line is attached to the thread. (mysql_qmake_flag_error.txt)

Next step was to execute "Qt 5.9 for Desktop (MinGW 5.3.0 32 bit)" from the startmenu of Windows. Switching the directory to the source, running qmake and mingw32-make:

CD C:\Qt_src\5.9.0\qtbase\src\plugins\sqldrivers\mysql
qmake mysql_edit.pro "INCLUDEPATH += C:\mariadb\include\mysql" "DEPENDSPATH += C:\mariadb\include\mysql" "LIBS += C:\mariadb\lib\libmariadb.lib"
mingw32-make

At the end I've four files under "C:\Qt_src\5.9.0\qtbase\plugins\sqldrivers" which are the compiled plugin. Which are working in a mingw environment with a MariaDB.

The MSVC17 way (not working)

Now to MSVC2017, it doesn't matter if I'm using 5.9.0, 5.9.1 or 5.9.2, I'm switching via "Qt 5.9 64-bit for Desktop (MSVC 2017)" from the startmenu to the sources, executing vcvarsall,running qmake, then nmake:

CD C:\Qt_src\5.9.0\qtbase\src\plugins\sqldrivers\mysql
CALL "C:\Program Files (x86)\Microsoft Visual Studio\2017\Professional\VC\Auxiliary\Build\vcvarsall.bat" x64
qmake mysql_edit.pro "INCLUDEPATH += C:\mariadb\include\mysql" "DEPENDSPATH += C:\mariadb\include\mysql" "LIBS += C:\mariadb\lib\libmariadb.lib"
nmake

Now the error - Qmake is complaining about the following:

Project ERROR: msvc-version.conf loaded but QMAKE_MSC_VER isn't set

I've searched through the net to find someone having a similar problem like me, but in this particular situation it seems like I'm the only one having this problem.

At the end I've a Qt built from source via MSVC17 and it won't work with a mingw compiled mysql plugin!

Just ask if you need more details.

Kind regards,
Mike