It now fails to build the DM7025 image at all and this is not related to the Rytec plugin issue - I changed the file date and that works fine. The failure happens very early in the build process. Unfortunately I am not strong in scripting/cross compilation so cannot debug the problem. It seems the problem is in frontend.c.
The last lines of the log file:
frontend.cpp:2124: warning: invalid conversion from 'int' to 'fe_spectral_inversion_t'
frontend.cpp:2125: warning: invalid conversion from 'int' to 'fe_spectral_inversion_t'
frontend.cpp: In member function 'bool eDVBFrontend::setSlotInfo(ePyObject)':
frontend.cpp:2730: warning: dereferencing type-punned pointer will break strict-aliasing rules
frontend.cpp:2736: warning: dereferencing type-punned pointer will break strict-aliasing rules
make[4]: *** [frontend.o] Error 1
make[4]: Leaving directory `/home/gerhard/Dreambox-E2-Pli-cdk/build-dm7025/tmp/work/enigma2-openpli+git8068+cdcde571a30af6e4856e220f43c82d50c85467a2-r21/git/lib/dvb'
make[3]: *** [all-recursive] Error 1
make[3]: Leaving directory `/home/gerhard/Dreambox-E2-Pli-cdk/build-dm7025/tmp/work/enigma2-openpli+git8068+cdcde571a30af6e4856e220f43c82d50c85467a2-r21/git/lib/dvb'
make[2]: *** [all-recursive] Error 1
make[2]: Leaving directory `/home/gerhard/Dreambox-E2-Pli-cdk/build-dm7025/tmp/work/enigma2-openpli+git8068+cdcde571a30af6e4856e220f43c82d50c85467a2-r21/git/lib'
make[1]: *** [all-recursive] Error 1
make[1]: Leaving directory `/home/gerhard/Dreambox-E2-Pli-cdk/build-dm7025/tmp/work/enigma2-openpli+git8068+cdcde571a30af6e4856e220f43c82d50c85467a2-r21/git'
FATAL: oe_runmake failed
Any help appreciated