This page is about building LineageOS for your mobile device of choice using a Gentoo PC as build-host.

If you want to build Gentoo linux to run on an Android device you can refer to this wiki page.

Gentoo forums post are my source: this one

There are the official LineageOS instructions. The following notes are the changes you need to do on your Gentoo system to be able to build instead of using Ubuntu.

Emerge the following:

#lineage
   app-arch/lz4
   app-arch/lzop
   media-gfx/imagemagick
   media-gfx/pngcrush
#aosp
   app-crypt/gnupg
   app-arch/zip[-natspec]
   app-arch/unzip
   dev-libs/libxslt
   dev-libs/libxml2
   dev-util/android-tools
   dev-util/ccache
   dev-util/gperf
   dev-vcs/git
   media-libs/libsdl
   media-libs/mesa
   net-misc/curl
   net-misc/rsync
   sys-devel/bc
   sys-devel/bison
   sys-devel/flex
   sys-devel/gcc[cxx]
   sys-libs/ncurses[abi_x86_32]
   sys-libs/ncurses-compat[abi_x86_32]
   sys-libs/readline[abi_x86_32]
   sys-libs/zlib[abi_x86_32]
   sys-process/schedtool
   sys-fs/squashfs-tools
   x11-base/xorg-proto
   x11-libs/libX11
   x11-libs/wxGTK:3.0 
   

Unset the following before building:

unset JAVAC
unset JAVA_HOME
unset JDK_HOME
unset LEX