I downloaded the src and in this directory I used the command:

configure -release -opensource -confirm-license -prefix C:\QT\6.1.3

in this directory. This went through without any problems.

Afterwards I should execute the command:

make -j8

which terminated after 15 % with an error message:

[ 15%] Built target Network_autogen
In file included from C:/Qt/6.1.3/Src/qtbase/include/QtCore/qstringconverter.h:1,
                 from C:/Qt/6.1.3/Src/qtbase/src/corelib/serialization/qtextstream.h:47,
                 from C:/Qt/6.1.3/Src/qtbase/include/QtCore/qtextstream.h:1,
                 from C:/Qt/6.1.3/Src/qtbase/src/corelib/io/qdebug.h:48,
                 from C:/Qt/6.1.3/Src/qtbase/include/QtCore/qdebug.h:1,
                 from C:/Qt/6.1.3/Src/qtbase/src/corelib/kernel/qcoreapplication.h:53,
                 from C:/Qt/6.1.3/Src/qtbase/include/QtCore/qcoreapplication.h:1,
                 from C:/Qt/6.1.3/Src/qtbase/include/QtCore/QCoreApplication:1,
                 from C:\Qt\6.1.3\Src\qtbase\src\tools\androiddeployqt\main.cpp:29:
C:/Qt/6.1.3/Src/qtbase/src/corelib/text/qstringconverter.h:189:87: internal compiler error: in make_rtl_for_nonlocal_decl, at cp/decl.c:6590
     Q_CORE_EXPORT static const Interface encodingInterfaces[Encoding::LastEncoding + 1];
                                                                                       ^
libbacktrace could not find executable to open
Please submit a full bug report,
with preprocessed source if appropriate.
See <https://sourceforge.net/projects/mingw-w64> for instructions.
qtbase\src\tools\androiddeployqt\CMakeFiles\androiddeployqt.dir\build.make:90: recipe for target 'qtbase/src/tools/androiddeployqt/CMakeFiles/androiddeployqt.dir/main.cpp.obj' failed
make[2]: *** [qtbase/src/tools/androiddeployqt/CMakeFiles/androiddeployqt.dir/main.cpp.obj] Error 1
CMakeFiles\Makefile2:12798: recipe for target 'qtbase/src/tools/androiddeployqt/CMakeFiles/androiddeployqt.dir/all' failed
make[1]: *** [qtbase/src/tools/androiddeployqt/CMakeFiles/androiddeployqt.dir/all] Error 2
[ 15%] Built target Gui_autogen
Makefile:144: recipe for target 'all' failed
make: *** [all] Error 2

I tried to look at the affected area, but unfortunately I couldn't figure it out.
I would like to thank you in advance for your answers.