To build illumos source code on OmniOS, you need to update system and install related tools (Assume you run as root) first:
# pkg update
# pkg install pkg:/developer/illumos-tools
Then clone illumos source code and compile ():
# git clone https://github.com/illumos/illumos-gate.git
# cd illumos-gate
# time ksh93 usr/src/tools/scripts/nightly /opt/onbld/env/omnios-illumos-gate
That’s it!
References:
Building illumos;
Build error of illumos-gate on OmniOS.