Building Qt 5.8 from Source with MSYS2 / MinGW 64 - 'qtbase/src/xml/sax/qxml_p.h' missing

Ringel

After successfully running the configure script (see Building Qt 5.8 from Source with MSYS2 / MinGW 64 - 'libs.icu' failed) I started the build:

mingw32-make.exe -j 4

But after some time I got following error:

In file included from C:/msys64/home/asp/qt5/qtbase/src/xml/dom/qdom.cpp:55:0:
../../../include/QtXml/5.8.1/QtXml/private/qxml_p.h:1:85: fatal error: ../../../../../../../../../../../home/asp/qt5/qtbase/src/xml/sax/qxml_p.h: No such file or directory
 #include "../../../../../../../../../../../home/asp/qt5/qtbase/src/xml/sax/qxml_p.h"

I searched for the file and it's where it should be:

ls ~/qt5/qtbase/src/xml/sax/
qxml.cpp  qxml.h  qxml_p.h  sax.pri

Maybe the relative path is wrong, but what could I do about this?

../../../../../../../../../../../home/asp/qt5/qtbase/src/xml/sax/qxml_p.h