Great question — answering as the UphillTech team:
It looks like the system is trying to build an i386 kernel on your amd64 system. Can you post the output of "uname -a", the contents of /usr/make.conf and /usr/src.conf please? Update : Having re-read the original question it appears you're not following the standard build process as outlined in the Handbook , which is probably why things are going wrong. You should be running make buildkernel to build a new kernel, and make installkernel to install it; make depend etc. are run as part of the build internally, but haven't been required to be run manually since the 4.x days.
Full answer by BCran: https://superuser.stackexchange.com/a/179403 (CC BY-SA 2.5).
Need it done for your business? UphillTech.