See how the mkmake command is called for each phase by running the make command in verbose mode as follows:
host% make SILENT= /<bin_dir>/tools/host/bin/mkmake \ /<work_dir>/build-NUCLEUS/ sources +l +b -- sources >> In <bin_dir>/bin/tools/host/bin/mkmake \ <work_dir>/build-NUCLEUS/ prod +l +m +b -- local_prod <bin_dir>/tools/host/bin/mkmake \ <work_dir>/build-NUCLEUS/ link +b -- local_link >> In src/os/iom/sys/sys/lib/mem link << In src/os/iom/sys/sys/lib/mem link done