$ cat /etc/portage/make.conf/*
## flags
WFLAGS="-Werror=odr -Werror=lto-type-mismatch -Werror=strict-aliasing"
COMMON_FLAGS="-march=native -O3 -pipe -flto ${WFLAGS}"
CFLAGS="${COMMON_FLAGS}"
CXXFLAGS="${COMMON_FLAGS}"
FCFLAGS="${COMMON_FLAGS}"
FFLAGS="${COMMON_FLAGS}"
LDFLAGS="${COMMON_FLAGS} ${LDFLAGS} ${WFLAGS}"
RUSTFLAGS="${RUSTFLAGS} -C target-cpu=native"
## localisation
L10N="en-GB"
LC_MESSAGES=C.utf8
## emerge
EMERGE_DEFAULT_OPTS="--ask --verbose --autounmask-write=n --quiet-build=y"
ACCEPT_LICENSE="-* @FREE @BINARY-REDISTRIBUTABLE"
GENTOO_MIRRORS="\
https://mirrors.gethosted.online/gentoo/ \
https://www.mirrorservice.org/sites/distfiles.gentoo.org/"
## USE
_OPTI="lto pgo"
_SYS="udev dbus syslog"
_SEC="elogind policykit pam"
_VIDEO="X opengl"
_CODEC="jpeg png raw"
_EXTRA="curl bluetooth"
_MINUS="-alsa -pulseaudio -sound -systemd -wayland"

USE="${_OPTI} ${_SYS} ${_SEC} ${_VIDEO} ${_AUDIO} ${_CODEC} ${_EXTRA} ${_MINUS}"