[Development] Building plugins/sqldrivers with QT 5.9 on windows

Hi, I'm trying to build the sqldriver plugins with qt 5.9. In 5.5 it was no problem to build the drivers with following qmake call: qmake INCLUDEPATH+=D:/QtBuild/Qt-Win64/Qt5-WinDeps-64bit/windeps\MySQL\include LIBS+=D:/QtBuild/Qt-Win64/Qt5-WinDeps-64bit/windeps\MySQL\lib\libmysql.lib D:/QtBuil

[Development] Automatic detection of Visual Studio Compiler

Hi, I've noticed that in QT 5.9 beta 2 the mkspecs for Visual Studio have changed to some kind of automatic detection. If I use win32-msvc, it seems that the studio version is not correctly detected and the configure script fails. 2017-04-25 15:47:56: Info: creating super cache file D:\QtBuild