Thanks Kev, "my" compile environment was given by JacKC as I was "not able" to build it up myself ;-) My plan was to use the MAME compile environment msys2 with everything inside (also git.exe that I must install it now) and the ability to update the tool with the script. I will check your website, maybe it is better to have an up-to-date GCC. Are you using it? Sometime newer builds break the compile process .....