arachne-pnr : Arachne PNR - free and open-source place and route tool for FPGAs ( https://github.com/cseed/arachne-pnr )
icestorm : IceStorm - tools for analyzing and creating bitstreams for Lattice iCE40 FPGAs ( http://www.clifford.at/icestorm/ )
sdcc : Small device C compiler (for various microprocessors) ( http://sdcc.sourceforge.net/ )
yosys : Yosys - Yosys Open SYnthesis Suite ( http://www.clifford.at/icestorm/ )
Add an ebuild in portage :
The ebuild is now in the portage tree.
You can also use layman : emerge layman then layman -a junkdrawer
For Paludis use this rsync : rsync://gentoo.zugaina.org/junkdrawer-portage
If you have a problem : ycarus(-at-)zugaina.org