The problem is caused by the different directories used by new FPC 3.0.4 packages (compared to previous versions of FPC in Debian).
Doing ./fpmake --globalunitdir="/usr/lib/fpc/3.0.4" doesn't work, since /usr/lib/fpc/3.0.4 does not exist. This works: ./fpmake --globalunitdir="/usr/lib/x86_64-linux-gnu/fpc/3.0.4" To fix this, I suggest to - Change / define the $FPCDIR variable inside Debian build scripts, to point to the new correct directory. - Or create a symlink /usr/lib/fpc/3.0.4 -> /usr/lib/x86_64-linux-gnu/fpc/3.0.4 . Regards, Michalis