Run the test suite and test some apps against it at least.
Let me check a couple of open bugs first.
No regressions in bug 212282 (some alt stuff) or bug 209796 so should be good to go.
ppc stable
Sparc stable. Working for me for over 30 days, and when built with FEATURES="test userpriv usersandbox" all 45,751 tests pass.
x86 stable
Stable for HPPA.
alpha/ia64 stable
====amd64==== 1. Compiles. 2. Tests(all who knows how many) are all ok. 3. Tested mainly with kuroo and is still functional and working. Portage 2.1.4.4 (default-linux/amd64/2007.0, gcc-4.1.2, glibc-2.6.1-r0, 2.6.23-gentoo-r9 x86_64) ================================================================= System uname: 2.6.23-gentoo-r9 x86_64 unknown Timestamp of tree: Sat, 15 Mar 2008 01:47:01 +0000 ccache version 2.4 [enabled] app-shells/bash: 3.2_p17-r1 dev-lang/python: 2.4.4-r9 dev-python/pycrypto: 2.0.1-r6 dev-util/ccache: 2.4-r7 sys-apps/baselayout: 1.12.11.1 sys-apps/sandbox: 1.2.18.1-r2 sys-devel/autoconf: 2.13, 2.61-r1 sys-devel/automake: 1.7.9-r1, 1.9.6-r2, 1.10 sys-devel/binutils: 2.18-r1 sys-devel/gcc-config: 1.4.0-r4 sys-devel/libtool: 1.5.26 virtual/os-headers: 2.6.23-r3 ACCEPT_KEYWORDS="amd64" CBUILD="x86_64-pc-linux-gnu" CFLAGS="-march=athlon64 -O2 -pipe" CHOST="x86_64-pc-linux-gnu" CONFIG_PROTECT="/etc /usr/kde/3.5/env /usr/kde/3.5/share/config /usr/kde/3.5/shutdown /usr/kde/4.0/env /usr/kde/4.0/share/config /usr/kde/4.0/shutdown /usr/share/X11/xkb /usr/share/config" CONFIG_PROTECT_MASK="/etc/env.d /etc/fonts/fonts.conf /etc/gconf /etc/revdep-rebuild /etc/terminfo /etc/udev/rules.d" CXXFLAGS="-march=athlon64 -O2 -pipe" DISTDIR="/distfiles" FEATURES="ccache collision-protect distlocks metadata-transfer multilib-strict parallel-fetch sandbox sfperms strict test unmerge-orphans userfetch userpriv" GENTOO_MIRRORS="http://distfiles.gentoo.org http://distro.ibiblio.org/pub/linux/distributions/gentoo" MAKEOPTS="-j2" PKGDIR="/usr/portage/packages" PORTAGE_RSYNC_OPTS="--recursive --links --safe-links --perms --times --compress --force --whole-file --delete --stats --timeout=180 --exclude=/distfiles --exclude=/local --exclude=/packages" PORTAGE_TMPDIR="/var/tmp" PORTDIR="/usr/portage" PORTDIR_OVERLAY="/overlay" SYNC="rsync://kv80/gentoo-portage" USE="X acl aiglx aim amd64 berkdb branding cli cracklib crypt cups dri fortran gdbm gpm gtk iconv imap ipv6 isdnlog midi mmx mpeg3 mudflap ncurses nls nptl nptlonly nvidia opengl openmp pam pcre perl pppd python qt3 readline reflection session sockets spl sqlite3 sse sse2 ssl tcpd unicode vim xcomposite xine xorg zlib" ALSA_CARDS="ali5451 als4000 atiixp atiixp-modem bt87x ca0106 cmipci emu10k1x ens1370 ens1371 es1938 es1968 fm801 hda-intel intel8x0 intel8x0m maestro3 trident usb-audio via82xx via82xx-modem ymfpci" ALSA_PCM_PLUGINS="adpcm alaw asym copy dmix dshare dsnoop empty extplug file hooks iec958 ioplug ladspa lfloat linear meter mulaw multi null plug rate route share shm softvol" APACHE2_MODULES="actions alias auth_basic authn_alias authn_anon authn_dbm authn_default authn_file authz_dbm authz_default authz_groupfile authz_host authz_owner authz_user autoindex cache dav dav_fs dav_lock deflate dir disk_cache env expires ext_filter file_cache filter headers include info log_config logio mem_cache mime mime_magic negotiation rewrite setenvif speling status unique_id userdir usertrack vhost_alias" ELIBC="glibc" INPUT_DEVICES="keyboard mouse evdev" KERNEL="linux" LCD_DEVICES="bayrad cfontz cfontz633 glk hd44780 lb216 lcdm001 mtxorb ncurses text" USERLAND="GNU" VIDEO_CARDS="nvidia" Unset: CPPFLAGS, CTARGET, EMERGE_DEFAULT_OPTS, INSTALL_MASK, LANG, LC_ALL, LDFLAGS, LINGUAS, PORTAGE_COMPRESS, PORTAGE_COMPRESS_FLAGS, PORTAGE_RSYNC_EXTRA_OPTS
amd64 stable, thanks Thomas for testing.
ppc64 stable
go with 3.5.9