Global USE flags

Flag Description Packages
X 5
alsa 4
browser_firefox Install extension for www-client/firefox 0
browser_firefox-bin Install extension for the www-client/firefox-bin 0
browser_seamonkey Install extension for the www-client/seamonkey 0
bundled-libs Use bundled version of dev-libs/expat 3
compressed Install extension as a compressed .xpi 0
debug Build with upstream's CXXFLAGS/LDFLAGS for debugging support; not recommended for normal use. 8
doc Create description of the eix cache file additionally in html format 5
emacs 2
examples Compile example character sheet as PDF 3
ggi 3
l10n_ 3
lzma 2
nls 8
optimization Accept upstream's choices for CXXFLAGS/LDFLAGS for optimization. Absense of this USE flag does not strip user's *FLAGS 2
perl Install 256colors perl script 2
sdl 3
selinux 2
split-usr 22
static 2
static-libs 2
strong-optimization Adds several more agressive CXXFLAGS/LDFLAGS for optimization like graphite (if available). May cause trouble with some buggy compiler versions. Absense of this USE flag does not strip user's *FLAGS 2
test 2
tinfo Whether to support (and require) sys-libs/ncurses[tinfo]. 2
tools Create separate binary for script helper tools; useful if they are called extremely often 3
xattr 2

Category USE flags

games-emulation

Flag Description Packages
cpu_flags_x86_mmx 2
dga 2
joystick 2
lirc 2
net Add network support 2
opengl 3
svga 2
xinerama 2
xv 2

Local USE flags

app-cdr

cdrtools

Flag Description
schily-tools Use libschily from app-shells/schily-tools

app-mobilephone

adb-sync

Flag Description
channel Install the adb-channel script

app-portage

eix

Flag Description
cpu_flags_x86_sse2
dep Make DEP=true the default which enables support for {,R,P,B}DEPEND but requires roughly double disk and memory.
jumbo-build Compile faster and produce better binary. Recommended unless compiling on a quite memory-restricted system.
meson Build with meson instead of autotools. Faster but less compatible
protobuf Use dev-libs/protobuf to suport proto output with --proto
required-use Make REQUIRED_USE=true the default which enables support for REQUIRED_USE but requires more disk and memory.
security This adds some checks which can prevent certain exploits if e.g. the eix code has a bug. If you use the hardened toolchain, using this flag does not increase security and can even lead to problems.
sqlite Compile in support for portage's sqlite backend; to actually use it you need additional configuration of portage and eix
src-uri Make SRC_URI=true the default which enables support for SRC_URI but requires roughly double disk and memory.
strong-security Add many checks to prevent exploits if eix code has a bug. This will slow down eix considerably. Use only if you are paranoid or have reasons to suspect a bug.
swap-remote Swap role of remote addresses in eix-remote, making the data from gpo.zugaina.org the first choice.
usr-portage Set last PORTDIR fallback to /usr/portage instead of /var/db/repos/gentoo

portage-bashrc-mv

Flag Description
ccache Install a script for CCACHE_* variable support. This requires dev-util/ccache
cflags Install a script for /etc/portage/package.cflags support. Requires app-portage/eix for fast parsing
remove-la Install a script to remove unneeded .ls files
title Install a script to display the expected merge time. Requires app-portage/portage-utils and app-shells/runtitle

app-shells

auto-fu-zsh

Flag Description
compile Byte-compile to speed up. Do not use this if you are cross-compiling

dash

Flag Description
libedit
vanilla Let echo escapes and -n work as decided by upstream

schily-tools

Flag Description
acl
caps
renameschily_calc Rename calc to scalc for compatibility with sci-mathematics/calc
renameschily_compare Rename compare to scompare for compatibility with imagemagick
renameschily_count Rename count to scount for compatibility with sys-devel/llvm
renameschily_getopt Rename count to scount for compatibility with sys-devel/llvm
renameschily_jsh Rename jsh to sjsh for compatibility with app-shells/heirloom-sh
renameschily_libschily Rename some manpages from libschily for compatibility with sys-apps/man
renameschily_man2html Rename man2html to sman2html for compatibility with sys-apps/man
renameschily_p Rename p to sp for compatibility with dev-util/wiggle
schilytools_bosh Install bosh, a shell which aims to be fully POSIX compatible
schilytools_calc Install calc, a bc clone
schilytools_calltree Install calltree, a cflow clone
schilytools_cdrtools Install programs provided by app-cdr/cdrtools
schilytools_change Install change, a program to change patterns in files
schilytools_compare Install compare, a cmp clone
schilytools_copy Install copy, a cp clone
schilytools_count Install count, a wc clone
schilytools_cpp Install cpp, a C preprocessor
schilytools_cstyle Install Cstyle, a C-codingstyle lint
schilytools_cut Install scut, a cut clone
schilytools_hdump Install hdump, a hexdump clone
schilytools_label Install label, a sun disk label manipulator
schilytools_lndir Install lndir, a program for creating symlinked directory trees
schilytools_man2html Install a man2html clone
schilytools_manmake Install manpages about the schily makefile system
schilytools_match Install match, a grep clone
schilytools_mdigest Install mdigest, e.g. covering md5sum sha*sum
schilytools_mountcd Install mountcd, a solaris CD comparison tool
schilytools_obosh Install obosh (formerly: osh), the original sVr4 (SunOS 5) shell with original bugs
schilytools_p Install p, a more program which filters non-printable characters
schilytools_paste Install spaste, a paste clone
schilytools_patch Install spatch, a patch clone
schilytools_pbosh Install pbosh, a shell which implements all POSIX features but only those (compatbilitiy testing!)
schilytools_pxupgrade Install pxupgrade: upgrading firmware in Plextor CD/DVD writers
schilytools_sccs Install sfind, a source code control system
schilytools_sfind Install sfind, a find clone
schilytools_smake Install smake, a make clone
schilytools_star Install programs provided by app-arch/star
schilytools_termcap Install termcap, a termcap compiler
schilytools_translit Install translit, a tr clone
schilytools_udiff Install udiff, a diff clone
schilytools_ved Install ved, a visual editor with features from vi and emacs
suid Install rscsi as SUID root
unicode

termcolors-mv

Flag Description
create Install DIR_COLORS-create perl script
poor Install poor man's variant which does not require coreutils-8.25 or newer

app-text

stardict

Flag Description
advertisement Enable stardict advertisements plugin
cal Enable calendar support using cal program
canberra Use libcanberra for sound playing
dictdotcn Enable dict.cn network plugin (for Chinese language)
espeak Enable text to speech synthesizer plugin using <pkg>app-accessibility/espeak</pkg> engine
flite Enable text to speech synthesizer plugin using <pkg>app-accessibility/flite</pkg> engine
fortune Enable plugin to read fortune messages using <pkg>games-misc/fortune-mod</pkg>. You may consider installing <pkg>games-misc/fortune-mod-all</pkg> to get all fortune messages.
gnome
gucharmap Enable plugin for unicode symbols description using <pkg>gnome-extra/gucharmap</pkg>
htmlparse Enable plugin to parse dictionaries with html content
info Enable plugin to read info pages
man Enable plugin to read manual pages
powerwordparse Enable plugin to parse powerword dictionaries
pronounce Install WyabdcRealPeopleTTS package (it is just many .wav files) to make StarDict pronounce English words
qqwry Enable QQWry plugin, which provides information (in Chinese language) about geographical positions, owner, etc. for IP addresses
spell
updateinfo Enable plugin to check for stardict updates
wikiparse Enable plugin to parse dictionaries in wikimedia format
wordnet Enable wordnet plugin to find similar English words using lexical database
xdxfparse Enable plugin to parse dictionaries in xdxf (XML Dictionary eXchange Format)
youdaodict Enable youdao.com network plugin (for Chinese language)

games-board

chessproblem

Flag Description
multithreading Install multithreading version
propagate-signal Use signal propagation for thread pruning. Requires more memory; it is faster in some cases, but slower in others
unlimited Do not limit number of threads by hardware_concurrency. Useful only for debugging

games-emulation

sdlmame

Flag Description
arcade Enable the Multiple Arcade Machine Emulator for arcade games support
mess Enable the Multi Emulator Super System for game system support
openmp

media-gfx

pqiv

Flag Description
archive Enable support for images in archives and cbX comic book files
ffmpeg
gtk2 Use gtk:2 instead of gtk:3
imagemagick
kernel_linux
pdf
postscript
webp

media-tv

nvtv

Flag Description
gtk

sundtek-tv

Flag Description
ld-preload-env Install LD_PRELOAD in /etc/env.d/50sundtek-tv
ld-preload-file Install /etc/ld.so.preload
pax-kernel Mark package which is necessary if you use a PAX kernel
pulseaudio

w_scan

Flag Description
plp-id-zero Apply experimental patch to force plp_id to 0 for DVB-T2. Seems to be necessary at least with some tuners in some regions

net-dns

noip-updater

Flag Description
ezipupd Use user/group ezipupd instead of nobody: Useful if you restrict outgoing network traffic for user nobody

net-print

foo2zjs

Flag Description
foomaticdb Add support for the foomatic printing driver database

sci-mathematics

reduce

Flag Description
gnuplot

sys-apps

less

Flag Description
less-select Add the less-select feature (additional options and a binary helper).
lesspipe Default to lesspipe.sh from app-text/lesspipe instead of the gentoo specific lesspipe.
original-gentoo Use the gentoo default for the LESS variable.
pcre
source Install sources for keybindings (only useful with less-select).

man

Flag Description
cache Use cache directory. Superfluous on modern machines

sys-block

parted

Flag Description
device-mapper Enable device-mapper support from <pkg>sys-fs/lvm2</pkg> in parted
readline
standalone Install a standalone version which provides all headers and binaries which collide with sys-block/parted:0. If this flag is not set, sys-block/parted:0 is pulled in to provide the non-installed headers and binaries.

zram-init

Flag Description
${IUSE}
l10n_${i}

sys-fs

squash_dir

Flag Description
aufs Prefer aufs
bundled-openrc-wrapper Install the bundled openrc-wrapper
overlayfs Prefer overlayfs
unionfs-fuse Prefer unionfs-fuse

squashfs-tools

Flag Description
lz4 Enable support for LZ4 compression using <pkg>app-arch/lz4</pkg>
lzo
xz Enable support for XZ ("LZMA2") compression using <pkg>app-arch/xz-utils</pkg>
zstd Enable support for ZSTD compression using <pkg>app-arch/zstd</pkg> (requires >=linux-4.14 or >=sys-fs/squashfuse-0.1.101_alpha20170917)

sys-power

pm-utils

Flag Description
ntp Install support for <pkg>net-misc/ntp</pkg>
video_cards_intel
video_cards_radeon