echo "MW=10" | grep -i -o -e "MW=\w*" would not give the right answer, MW=10 when grep-2.5.4-r1 are used. It is always reproducible on a box with Opteron CPU. The box uses http://gentoo.osuosl.org/releases/amd64/current/stage3-amd64-20090611.tar.bz2. The gentoo is totally freshely installed base system without strong optimization emerge --info Portage 2.1.6.13 (default/linux/amd64/2008.0, gcc-4.3.2, glibc-2.8_p20080602-r1, 2.6.30-gentoo-r1 x86_64) ================================================================= System uname: Linux-2.6.30-gentoo-r1-x86_64-Quad-Core_AMD_Opteron-tm-_Processor_2378-with-glibc2.2.5 Timestamp of tree: Tue, 16 Jun 2009 22:30:01 +0000 app-shells/bash: 3.2_p39 dev-lang/python: 2.5.4-r2 sys-apps/baselayout: 2.0.1 sys-apps/openrc: 0.4.3-r3 sys-apps/sandbox: 1.6-r2 sys-devel/autoconf: 2.63 sys-devel/automake: 1.10.2 sys-devel/binutils: 2.18-r3 sys-devel/gcc-config: 1.4.1 sys-devel/libtool: 1.5.26 virtual/os-headers: 2.6.27-r2 ACCEPT_KEYWORDS="amd64" CBUILD="x86_64-pc-linux-gnu" CFLAGS="-O2 -pipe" CHOST="x86_64-pc-linux-gnu" CONFIG_PROTECT="/etc /var/spool/torque" CONFIG_PROTECT_MASK="/etc/ca-certificates.conf /etc/env.d /etc/gconf /etc/gentoo-release /etc/revdep-rebuild /etc/sandbox.d /etc/terminfo /etc/udev/rules.d" CXXFLAGS="-O2 -pipe" DISTDIR="/usr/portage/distfiles" FEATURES="distlocks fixpackages parallel-fetch protect-owned sandbox sfperms strict unmerge-orphans userfetch" GENTOO_MIRRORS="http://distfiles.gentoo.org http://distro.ibiblio.org/pub/linux/distributions/gentoo" LDFLAGS="-Wl,-O1" MAKEOPTS="-j9" PKGDIR="/usr/portage/packages" PORTAGE_CONFIGROOT="/" 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" SYNC="rsync://rsync.gentoo.org/gentoo-portage" USE="acl amd64 berkdb bzip2 cli cracklib crypt cups dri fortran gdbm gpm iconv ipv6 isdnlog midi mmx mudflap multilib ncurses nls nptl nptlonly openmp pam pcre perl pppd python readline reflection session spl sse sse2 ssl symlink sysfs tcpd unicode 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 mmap_emul 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="fbdev glint i810 intel mach64 mga neomagic nv r128 radeon savage sis tdfx trident vesa vga via vmware voodoo" Unset: CPPFLAGS, CTARGET, EMERGE_DEFAULT_OPTS, FFLAGS, INSTALL_MASK, LANG, LC_ALL, LINGUAS, PORTAGE_COMPRESS, PORTAGE_COMPRESS_FLAGS, PORTAGE_RSYNC_EXTRA_OPTS, PORTDIR_OVERLAY If I mask >=dev-libs/libpcre-7.9-r1 and >=sys-apps/grep-2.5.4-r1, emerge dev-libs/libpcre-7.8 and sys-apps/grep-2.5.1a-r1, grep gives the right answer. The problem exists on several Intel Quad Core computers too (~amd64). But on an old Athlon64 Computer, the problem does not exists even though grep version is same.
I can confirm this problem on my Opteron machine: # emerge --info Portage 2.2_rc33 (default/linux/amd64/2008.0/desktop, gcc-4.3.3, glibc-2.8_p20080602-r1, 2.6.27.25 x86_64) ================================================================= System uname: Linux-2.6.27.25-x86_64-Quad-Core_AMD_Opteron-tm-_Processor_2380-with-gentoo-2.0.1 Timestamp of tree: Wed, 17 Jun 2009 03:15:01 +0000 app-shells/bash: 4.0_p24 dev-java/java-config: 2.1.8-r1 dev-lang/python: 2.6.2-r1 dev-util/cmake: 2.6.4 sys-apps/baselayout: 2.0.1 sys-apps/openrc: 0.4.3-r3 sys-apps/sandbox: 2.0 sys-devel/autoconf: 2.13, 2.63-r1 sys-devel/automake: 1.5, 1.7.9-r1, 1.9.6-r2, 1.10.2, 1.11 sys-devel/binutils: 2.19.1-r1 sys-devel/gcc-config: 1.4.1 sys-devel/libtool: 2.2.6a virtual/os-headers: 2.6.28-r1 ACCEPT_KEYWORDS="amd64 ~amd64" CBUILD="x86_64-pc-linux-gnu" CFLAGS="-march=barcelona -mtune=barcelona -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/share/config /var/lib/hsqldb" CONFIG_PROTECT_MASK="/etc/X11/Sessions /etc/X11/app-defaults /etc/X11/xinit /etc/adobe /etc/bonobo-activation /etc/ca-certificates /etc/ca-certificates.conf /etc/dbus-1 /etc/env.d /etc/env.d/java/ /etc/fonts /etc/fonts/fonts.conf /etc/foomatic /etc/games /etc/gconf /etc/gentoo-release /etc/gimp /etc/gnome-vfs-2.0 /etc/gre.d /etc/gtk-2.0 /etc/hp /etc/hsqldb /etc/htdig /etc/init.d /etc/iproute2 /etc/java-config-2 /etc/lftp /etc/logrotate.d /etc/ntop /etc/opt /etc/pango /etc/profile.d /etc/qt4 /etc/revdep-rebuild /etc/sandbox.d /etc/sasl2 /etc/sensors.d /etc/sgml /etc/sound /etc/ssl /etc/ssmtp /etc/t1lib /etc/terminfo /etc/udev/rules.d /etc/vbox /etc/xdg /etc/xinetd.d /etc/xml" CXXFLAGS="-march=barcelona -mtune=barcelona -O2 -pipe" DISTDIR="/usr/portage/distfiles" EMERGE_DEFAULT_OPTS="--alphabetical --with-bdeps=y" FEATURES="collision-protect distlocks fixpackages parallel-fetch protect-owned sandbox sfperms strict unmerge-orphans userfetch userpriv usersandbox" GENTOO_MIRRORS="ftp://linux.rz.ruhr-uni-bochum.de/gentoo-mirror/ ftp://sunsite.informatik.rwth-aachen.de/pub/Linux/gentoo ftp://ftp.tu-clausthal.de/pub/linux/gentoo/ http://gentoo.oregonstate.edu http://www.ibiblio.org/pub/Linux/distributions/gentoo" LDFLAGS="-Wl,-O1,--hash-style=gnu,--sort-common,--as-needed" LINGUAS="de en" MAKEOPTS="-j7" PKGDIR="/usr/portage/packages" PORTAGE_CONFIGROOT="/" 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="/usr/local/portage" SYNC="rsync://rsync.de.gentoo.org/gentoo-portage" USE="3dnow 3dnowext X a52 aac acpi alsa amd64 berkdb branding bzip2 cairo cdda cdr cli cracklib crypt cups dbus dri dvd dvdr dvdread emboss encode evo fam ffmpeg firefox flac gdbm gif gnutls gtk iconv idn isdnlog jpeg jpeg2k kde lame libnotify mad midi mikmod mmap mmx mmxext mp3 mp4 mpeg mudflap multilib ncurses nls nptl nptlonly nsplugin ogg opengl openmp pam pcre pdf png ppds pppd qt3 qt3support qt4 quicktime readline reflection sdl session slang spell spl sse sse2 ssl startup-notification svg sysfs theora threads tiff truetype unicode usb vcd vorbis x264 xml xorg xulrunner xv xvid zlib" ALSA_CARDS="emu10k1 hda-intel" ALSA_PCM_PLUGINS="adpcm alaw asym copy dmix dshare dsnoop empty extplug file hooks iec958 ioplug ladspa lfloat linear meter mmap_emul mulaw multi null plug rate route share shm softvol" ELIBC="glibc" INPUT_DEVICES="keyboard mouse" KERNEL="linux" LINGUAS="de en" USERLAND="GNU" VIDEO_CARDS="nv nvidia" Unset: CPPFLAGS, CTARGET, FFLAGS, INSTALL_MASK, LANG, LC_ALL, PORTAGE_COMPRESS, PORTAGE_COMPRESS_FLAGS, PORTAGE_RSYNC_EXTRA_OPTS # qlist -CIve grep libpcre dev-libs/libpcre-7.9-r1 sys-apps/grep-2.5.4-r1 Another system with AMD Sempron CPU (stable amd64 system) and the same packages installed is not affected.
Ah, screw my previous comment (I shouldn't post early in the morning): On my Opteron machine grep is doing fine whereas on the Sempron box it isn't: Opteron:~ # echo "MW=10" | grep -i -o -e "MW=\w*" MW=10 Opteron:~ # Sempron:~ # echo "MW=10" | grep -i -o -e "MW=\w*" Sempron:~ # Sempron:~ # emerge -qpv grep libpcre [ebuild R ] dev-libs/libpcre-7.9-r1 USE="bzip2 cxx -doc -static-libs (unicode) zlib" [ebuild R ] sys-apps/grep-2.5.4-r1 USE="nls pcre" # emerge --info Portage 2.1.6.13 (default/linux/amd64/2008.0/server, gcc-4.3.2, glibc-2.8_p20080602-r1, 2.6.27.24 x86_64) ================================================================= System uname: Linux-2.6.27.24-x86_64-AMD_Sempron-tm-_Processor_3000+-with-glibc2.2.5 Timestamp of tree: Sat, 13 Jun 2009 21:15:01 +0000 app-shells/bash: 3.2_p39 dev-lang/python: 2.5.4-r2 sys-apps/baselayout: 1.12.11.1 sys-apps/sandbox: 1.6-r2 sys-devel/autoconf: 2.63 sys-devel/automake: 1.7.9-r1, 1.9.6-r2, 1.10.2 sys-devel/binutils: 2.18-r3 sys-devel/gcc-config: 1.4.1 sys-devel/libtool: 1.5.26 virtual/os-headers: 2.6.27-r2 ACCEPT_KEYWORDS="amd64" CBUILD="x86_64-pc-linux-gnu" CFLAGS="-march=k8 -mtune=k8 -O2 -pipe" CHOST="x86_64-pc-linux-gnu" CONFIG_PROTECT="/etc /var/bind" CONFIG_PROTECT_MASK="/etc/ca-certificates.conf /etc/env.d /etc/fonts/fonts.conf /etc/gconf /etc/init.d /etc/php/apache2-php5/ext-active/ /etc/php/cgi-php5/ext-active/ /etc/php/cli-php5/ext-active/ /etc/revdep-rebuild /etc/sandbox.d /etc/terminfo /etc/udev/rules.d" CXXFLAGS="-march=k8 -mtune=k8 -O2 -pipe" DISTDIR="/usr/portage/distfiles" EMERGE_DEFAULT_OPTS="--alphabetical" FEATURES="distlocks fixpackages parallel-fetch protect-owned sandbox sfperms strict unmerge-orphans userfetch userpriv usersandbox" GENTOO_MIRRORS="ftp://linux.rz.ruhr-uni-bochum.de/gentoo-mirror/ ftp://sunsite.informatik.rwth-aachen.de/pub/Linux/gentoo ftp://ftp.tu-clausthal.de/pub/linux/gentoo/ http://gentoo.oregonstate.edu http://www.ibiblio.org/pub/Linux/distributions/gentoo" LDFLAGS="-Wl,--as-needed" LINGUAS="de en" MAKEOPTS="-j1" PKGDIR="/usr/portage/packages" PORTAGE_CONFIGROOT="/" 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="/home/.portage/tmp" PORTDIR="/usr/portage" PORTDIR_OVERLAY="/usr/local/layman/poly-c" SYNC="rsync://rsync.de.gentoo.org/gentoo-portage" USE="acpi amd64 apache2 berkdb bzip2 cli cracklib crypt fam gdbm gnutls iconv jpeg mmx mmxext mudflap multilib ncurses nls nptl nptlonly pam pcre png readline reflection session slang spl sse sse2 ssl svg sysfs truetype xml zip zlib" APACHE2_MODULES="actions alias auth_basic auth_digest authn_anon authn_dbd 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 dbd deflate dir disk_cache env expires ext_filter file_cache filter headers ident imagemap include info log_config logio mem_cache mime mime_magic negotiation proxy proxy_ajp proxy_balancer proxy_connect proxy_http rewrite setenvif so speling status unique_id userdir usertrack vhost_alias" ELIBC="glibc" KERNEL="linux" LINGUAS="de en" USERLAND="GNU" Unset: CPPFLAGS, CTARGET, FFLAGS, INSTALL_MASK, LANG, LC_ALL, PORTAGE_COMPRESS, PORTAGE_COMPRESS_FLAGS, PORTAGE_RSYNC_EXTRA_OPTS
Does grep-2.5.4 work?
repeat count doesn't work either using 2.5.4-r1
seems to work for me with grep-2.6
