Gentoo make.conf

CFLAGS="-O2 -march=znver1"
# GCC 6.3+

# CFLAGS="-O2 -march=bdver4 -mno-fma4 -mno-tbm -mno-xop -mno-lwp"
# GCC 5.4

# CFLAGS="-O2 -pipe"
CXXFLAGS="${CFLAGS}"
CHOST="x86_64-pc-linux-gnu"
USE="X a2jmidid a52 aac aacplus alsa audacious cdda cddb cdio consolekit
     corefonts cpudetection dbus dssi dts encode equalizer faac ffmpeg fftw
     flac fluidsynth freesound gif gtk gudev hwdb icu id3 id3tag ieee1394 jack
     jpeg ladspa lame libsamplerate lv2 mad matroska midi minizip mp3 mp4 mpeg
     mpg123 musepack musicbrainz netjack nls ogg opengl opus pcre16 png policykit
     python qt3support qt5 quicktime realtime rubberband savedconfig shine
     shout skins sndfile soundtouch svg taglib theora tiff timidity truetype
     twolame udev upower usb vamp vcd vorbis wav wavpack x264 xine xkb xml
     xvfb xvid xvmc -pulseaudio -xscreensaver"
PORTDIR="/usr/portage"
DISTDIR="${PORTDIR}/distfiles"
PKGDIR="${PORTDIR}/packages"
MAKEOPTS="-j8"
ABI_X86="32 64"
ACCEPT_KEYWORDS="amd64"
ACCEPT_LICENSE="*"
INPUT_DEVICES="libinput"
# pcxhr has been omitted as the latest alsa-tools fails with it.
ALSA_CARDS="emu10k1 emu10k1x hdsp hdspm ice1712 mixart rme32 rme96 sb16 sbawe sscape usb-usx2y vx222"
USE_PYTHON="2.7 3.4 3.5 3.6"
PYTHON_TARGETS="python2_7 python3_4 python3_5 python3_6"
PYTHON_SINGLE_TARGET="python3_6"
EMERGE_DEFAULT_OPTS="-v --quiet"
# Required to allow libshout-idjc to replace the file(s) installed by libshout.
# This should not hurt pkgs needing libshout.
COLLISION_IGNORE="/usr/share/aclocal/"


GENTOO_MIRRORS="http://mirror.csclub.uwaterloo.ca/gentoo-distfiles/ ftp://mirror.csclub.uwaterloo.ca/gentoo-distfiles/ rsync://rsync.gtlib.gatech.edu/gentoo http://www.gtlib.gatech.edu/pub/gentoo ftp://ftp.gtlib.gatech.edu/pub/gentoo http://gentoo.osuosl.org/ rsync://mirrors.rit.edu/gentoo/ ftp://mirrors.rit.edu/gentoo/ http://mirrors.rit.edu/gentoo/ http://mirror.lug.udel.edu/pub/gentoo/ ftp://cosmos.illinois.edu/pub/gentoo/ http://cosmos.illinois.edu/pub/gentoo/"
CPU_FLAGS_X86="aes avx avx2 fma3 mmx mmxext pclmul popcnt sse sse2 sse3 sse4_1 sse4_2 sse4a ssse3"
GRUB_PLATFORMS="efi-64"
VIDEO_CARDS="amdgpu radeonsi"