Hi.
I tried to install package sys-kernel/calculate-sources-3.13.7::calculate and got error:

>>> Compiling source in /var/tmp/portage/sys-kernel/calculate-sources-3.13.7/work/linux-3.13.7-calculate ...
 * The user is not root
 * ERROR: sys-kernel/calculate-sources-3.13.7::calculate failed (compile phase):
 *   kernel build failed
 * 
 * Call stack:
 *     ebuild.sh, line   93:  Called src_compile
 *   environment, line 4164:  Called calculate-kernel-5_src_compile
 *   environment, line  652:  Called vmlinuz_src_compile
 *   environment, line 5164:  Called die
 * The specific snippet of code:
 *       DEFAULT_KERNEL_SOURCE="${S}" CMD_KERNEL_DIR="${S}" cl-kernel --ebuild -o ${CL_KERNEL_OPTS} --kerneldir=${S} --set cl_kernel_cache_path=${WORKDIR}/cache --set cl_kernel_temp_path=${S}/temp --set cl_kernel_install_path=${WORKDIR} || die "kernel build failed";

Output of emerge --info '=sys-kernel/calculate-sources-3.13.7::calculate'

Portage 2.2.7 (default/linux/amd64/13.0/desktop/kde, gcc-4.7.3, glibc-2.17, 3.12.9-calculate x86_64)
=================================================================
                        System Settings
=================================================================
System uname: Linux-3.12.9-calculate-x86_64-Pentium-R-_Dual-Core_CPU_E5400_@_2.70GHz-with-gentoo-13.11.1
KiB Mem:     2052368 total,    385128 free
KiB Swap:    2049020 total,   1427152 free
Timestamp of tree: Mon, 28 Apr 2014 05:30:01 +0000
ld GNU ld (GNU Binutils) 2.23.2
app-shells/bash:          4.2_p45
dev-java/java-config:     2.2.0
dev-lang/python:          2.7.5-r3, 3.3.3
dev-util/cmake:           2.8.11.2
dev-util/pkgconfig:       0.28
sys-apps/baselayout:      2.2
sys-apps/openrc:          0.12.4
sys-apps/sandbox:         2.6-r1
sys-devel/autoconf:       2.13, 2.69
sys-devel/automake:       1.11.6, 1.12.6, 1.13.4
sys-devel/binutils:       2.23.2
sys-devel/gcc:            4.7.3-r1
sys-devel/gcc-config:     1.7.3
sys-devel/libtool:        2.4.2
sys-devel/make:           3.82-r4
sys-kernel/linux-headers: 3.9 (virtual/os-headers)
sys-libs/glibc:           2.17
Repositories: gentoo kde lcd-filtering mozilla gentoo-zh proaudio calculate
Installed sets: @custom
ACCEPT_KEYWORDS="amd64" 
ACCEPT_LICENSE="*" 
CBUILD="x86_64-pc-linux-gnu" 
CFLAGS="-O2 -march=native -pipe" 
CHOST="x86_64-pc-linux-gnu" 
CONFIG_PROTECT="/etc /usr/share/config /usr/share/gnupg/qualified.txt /usr/share/themes/oxygen-gtk/gtk-2.0 /usr/share/themes/oxygen-gtk/gtk-3.0" 
CONFIG_PROTECT_MASK="/etc/ca-certificates.conf /etc/env.d /etc/fonts/fonts.conf /etc/gconf /etc/gentoo-release /etc/revdep-rebuild /etc/sandbox.d /etc/splash /etc/terminfo" 
CXXFLAGS="-O2 -march=native -pipe" 
DISTDIR="/usr/portage/distfiles" 
EMERGE_DEFAULT_OPTS=" --jobs=1" 
FCFLAGS="-O2 -pipe" 
FEATURES="assume-digests binpkg-logs config-protect-if-modified distlocks ebuild-locks fixlafiles merge-sync metadata-transfer news parallel-fetch preserve-libs protect-owned sandbox sfperms strict unknown-features-warn unmerge-logs unmerge-orphans userfetch userpriv usersandbox usersync" 
FFLAGS="-O2 -pipe" 
GENTOO_MIRRORS="http://mirror.yandex.ru/gentoo-distfiles/" 
LANG="ru_RU.UTF-8" 
LDFLAGS="-Wl,-O1 -Wl,--as-needed" 
MAKEOPTS="-j1" 
PKGDIR="/usr/portage/packages" 
PORTAGE_CONFIGROOT="/" 
PORTAGE_RSYNC_OPTS="--recursive --links --safe-links --perms --times --omit-dir-times --compress --force --whole-file --delete --stats --human-readable --timeout=180 --exclude=/distfiles --exclude=/local --exclude=/packages" 
PORTAGE_TMPDIR="/var/tmp" 
PORTDIR="/usr/portage" 
PORTDIR_OVERLAY="/var/lib/layman/kde /var/lib/layman/lcd-filtering /var/lib/layman/mozilla /var/lib/layman/gentoo-zh /var/lib/layman/pro-audio /var/lib/layman/calculate" 
USE="3dnow X a52 aac acl acpi alsa amd64 berkdb bluetooth branding bzip2 cairo cdda cdr cli consolekit cracklib crypt cups custom-cflags custom-optimization cxx dbus declarative dri dts dvd dvdr emboss encode exif fam firefox flac fortran gbm gdbm gif gles1 gles2 gpm gstreamer gtk iconv icu javascript jit jpeg kde kipi lcdfilter lcms ldap libnotify lzma mad mmx mng modules mp3 mp4 mpeg ncurses nls nptl ogg opengl openmp openvg osmesa pam pango pch pcre pdf phonon plasma png policykit ppds qt qt3support qt4 quicktime readline ruby19 ruby20 sane scanner sdl semantic-desktop session shared-dricore spell sse sse2 ssl ssse2 ssse3 startup-notification steamruntime svg tcpd themes_CLD tiff truetype udev udisks unicode upower usb vdpau vorbis win32codecs wxwidgets x264 xa xcb xcomposite xml xscreensaver xv xvid zlib" ABI_X86="64" 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" APACHE2_MODULES="authn_core authz_core socache_shmcb unixd 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 cgi cgid 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" CALLIGRA_FEATURES="kexi words flow plan sheets stage tables krita karbon braindump author" CAMERAS="ptp2" COLLECTD_PLUGINS="df interface irq load memory rrdtool swap syslog" ELIBC="glibc" GPSD_PROTOCOLS="ashtech aivdm earthmate evermore fv18 garmin garmintxt gpsclock itrax mtk3301 nmea ntrip navcom oceanserver oldstyle oncore rtcm104v2 rtcm104v3 sirf superstar2 timing tsip tripmate tnt ublox ubx" INPUT_DEVICES="evdev" KERNEL="linux" LCD_DEVICES="bayrad cfontz cfontz633 glk hd44780 lb216 lcdm001 mtxorb ncurses text" LIBREOFFICE_EXTENSIONS="presenter-console presenter-minimizer" LINGUAS="en ru" OFFICE_IMPLEMENTATION="libreoffice" PHP_TARGETS="php5-5" PYTHON_SINGLE_TARGET="python2_7" PYTHON_TARGETS="python2_7 python3_3" RUBY_TARGETS="ruby19 ruby20" USERLAND="GNU" VIDEO_CARDS="nvidia" XTABLES_ADDONS="quota2 psd pknock lscan length2 ipv4options ipset ipp2p iface geoip fuzzy condition tee tarpit sysrq steal rawnat logmark ipmark dhcpmac delude chaos account" 
Unset:  CPPFLAGS, CTARGET, INSTALL_MASK, LC_ALL, PORTAGE_BUNZIP2_COMMAND, PORTAGE_COMPRESS, PORTAGE_COMPRESS_FLAGS, PORTAGE_RSYNC_EXTRA_OPTS, SYNC, USE_PYTHON

=================================================================
                        Package Settings
=================================================================

sys-kernel/calculate-sources-3.13.7 was built with the following:
USE="(policykit) -build -minimal -symlink -vmlinuz" ABI_X86="64" 

Use flags for package sys-kernel/calculate-sources:

sys-kernel/calculate-sources symlink vmlinuz

Output uname -a:

Linux degeso 3.12.9-calculate #1 SMP PREEMPT Mon Feb 3 09:16:02 UTC 2014 x86_64 Pentium(R) Dual-Core CPU E5400 @ 2.70GHz GenuineIntel GNU/Linux