Gentoo

LDFLAGS='-Wl,-O1,--enable-new-dtags,--sort-common,--allow-multiple-definition,--
allow-multiple-definition,--relax -z combreloc -z muldefs -s'

CFLAGS="-g0 -DTT_CONFIG_OPTION_BYTECODE_INTERPRETER -pipe -O3 -march=k8 -fweb -funswitch-loops -funroll-all-loops -funit-at-a-time -fsched2-use-traces -fsched2-use-superblocks -fsched-stalled-insns=12 -frename-registers -fprefetch-loop-arrays -fpeel-loops -fomit-frame-pointer -fmerge-all-constants -finline-limit=32768 -finline-functions -ffunction-sections -ffast-math -fdata-sections -fbranch-target-load-optimize2"

CXXFLAGS="-g0 -DTT_CONFIG_OPTION_BYTECODE_INTERPRETER -pipe -O3 -march=pentium4 -fweb -funswitch-loops -funroll-all-loops -funit-at-a-time -fsched2-use-traces -fsched2-use-superblocks -fsched-stalled-insns=12 -frename-registers -fprefetch-loop-arrays -fpeel-loops -fomit-frame-pointer -fmerge-all-constants -finline-limit=32768 -finline-functions -ffunction-sections -ffast-math -fdata-sections -fbranch-target-load-optimize2 -fvisibility-inlines-hidden -fabi-version=0 -fpermissive -fno-enforce-eh-specs"

FEATURES="-ccache buildpkg -sandbox"
MAKEOPTS="-j1"
PORTAGE_NICENESS='0'
ACCEPT_KEYWORDS="~x86 x86"
CLEAN_DELAY="7"
CONFIG_PROTECT="/etc /var/qmail/control /usr/share/config /usr/kde/2/share/config /usr/kde/3/share/config"
CONFIG_PROTECT_MASK="/etc/gconf"

CBUILD=i686-pc-linux-gnu
CCHOST=i686-pc-linux-gnu
CCHOST=i686-pc-linux-gnu
CHOST=i686-pc-linux-gnu
CTARGET=i686-pc-linux-gnu

ARCH="x86"
AUTOCLEAN="yes"
NOCOLOR="false"
PORTAGE_BINHOST_CHUNKSIZE="16384"
RSYNC_RETRIES="2"
RSYNC_TIMEOUT="64"
USE_EXPAND="VIDEO_CARDS INPUT_DEVICES LINGUAS"

SYNC="rsync://65.19.163.230/gentoo-portage"
GENTOO_MIRRORS="http://64.27.65.115/gentoo http://193.1.219.100/pub/gentoo/ http://209.221.142.124/ ftp://141.219.155.230/gentoo/source http://141.219.155.230/gentoo/"
FETCHCOMMAND="/usr/bin/wget -t 2 -v --dns-timeout=20 --dns-cache=off -nv --read-timeout=600 -o /RamTemp/wget_log --connect-timeout=12 -P \${DISTDIR} \${URI}"
RESUMECOMMAND="/usr/bin/wget -t 1 -v -c --dns-timeout=12 --dns-cache=off -nv --read-timeout=600 -o /RamTemp/wget_log --progress=bar --connect-timeout=12 -P \${DISTDIR} \${URI}"

DISTDIR=/usr/portage/distfiles
PORTAGE_TMPDIR=/var/tmp
PORTDIR=/usr/portage
PKGDIR=/usr/portage/packages
RPMDIR=/usr/portage/rpm
PORTDIR_OVERLAY="/var/overlay/bmg-gnome /var/overlay/bmg-main /usr/portage/packages/overlay"

USE="aac acpi aim aliaschain amd antlr apache2 artswrappersuid asterisk \
 async audiofile bcmath bdf blender-game bsh bzlib calendar cap caps \
 cddb cdf cdparanoia cdrom chroot clamav clanJavaScript clanVoice \
 cle266 clearpasswd client clisp cmucl cnamefix codecs curl \
 curlwrappers dbm dbx dedicated devfs devfs26 devmap dga dio distcache \
 distribution divx4linux dlopen dmx dnd dnsdb drac dv dvb dvd dvdr \
 dvdread editor edl erandom escreen ethereal etwin evo evolution exif \
 faac faad fastcgi fax fbcon fbdev ffmpeg flash foreign-package \
 freetts freetype frlargefiles fs ftp GAPING_SECURITY_HOLE gb gcc gcj \
 gd gimp gimpprint ginac glade glgd glut gmp gmtfull gmthigh gmtsuppl \
 gmttria gnomedb gnuplot gnutls gps graphviz gs gsl hdf5 icq icu idl \
 ieee1394 image imap imlib2 inetd innodb ipalias ipcs ipv6 ipv6arpa \
 jack-tmpfs java javacomm javadoc javamail javascript jce jikes \
 joystick jp2 jsch ldirectord leaf leim lesstif libcaca libdsk libgda \
 libsamplerate lids lirc live lmtp lm_sensors log4j ltsp lua \
 lufsusermount lynxkeymap lzo lzw lzw-tiff m17n-lib md5sum mdb mixer \
 mldonkeypango mmap mmx mng monkey mozcalendar mozp3p mozsvg \
 mozxmlterm mpeg4 mpi mplayer msdav mssql mule multicall multipleip \
 nagios-dns nagios-ntp nagios-ping nagios-ssh native net netcdf \
 network nptl ntlm nvidia objc ocaml offensive ofx ooo-kde openal \
 openssh opie orathreads oro pam-mysql pcap pcre pdf pg-hier \
 pg-intdatetime pg-vacuumdelay php physfs pic portaudio posix ppds \
 prelude print procmail pthreads pwdb quotes radius regexp remote \
 rhino rogue rplay rtc S3TC sasl savedconfig semanticfix serial server \
 servlet-2.3 servlet-2.4 session shaper shared sharedmem sheep silc \
 simplexml skey skk slp smime sndfile snmp snortsam soap sockets \
 socks5 softmmu softquota sox spamassassin speedo spl sqlite3 src sse \
 sse2 stats stencil-buffer svg sysvipc szip t1lib tcc tcl tga theora \
 threads tidy timidity tlen tokenizer tools transcode translator \
 transparent-proxy type1 uim uml unsafe usagi usb uudeview v4l v4l2 \
 vanilla vda vhosts vim-with-x vpopmail wddx wildlsearch wmf wxwin \
 wxwindows X509 Xaw3d xbase xchatdccserver xchattext xerces xface \
 xforms xfs xine xinerama xmlrpc xpm xprint xrandr xsl xvid yahoo yaz \
 yv12 zeo zvbi -libg"

А ничего не надо. Этот файл в каждом LiveCD уже настроен на подходящие тебе значения

А почему содержание столь велико? Я тут погуглил, а не проще вот так написать?

CFLAGS="-march=k8 -O3 -fforce-addr -funit-at-a-time -fomit-frame-pointer -frename-registers -fprefetch-loop-arrays -ftracer -funswitch-loops -ffast-math" CHOST="x86_64-pc-linux-gnu" CXXFLAGS="${CFLAGS}" GENTOO_MIRRORS="http://gentoo.osuosl.org/"; USE="nptl nptlonly alsa oss dvdr cdr acpi 3dnow x86_64 lm_sensors kde qt gtk2 userlocales"

Этого не достаточно?

вы так дружно на счет О3 уверены?

Это взято из классического багрепорта http://bugs.gentoo.org/show_bug.cgi?id=74072
Однако цель достигнута - google использован по назначению.
На самом деле безопасные флаги -
CFLAGS="-march=k8 -O2 -fomit-frame-pointer -pipe"