I am trying to build cyanogenmod 12 from rom source. I have succesfully built the rom for nexus 5 (hammerhead), following the instructions in their wiki.
But when I am trying to build cm12 for devices like samsung grand duos, I am unable to proceed, as I can't find the device name in the lunch menu.
How do I build the rom for such unofficial devices? What is the procedure?
Check out these instructions. It, along with the rest of the development section of the wiki, should have the info you need.