emerge -uavDN @world

These are the packages that would be merged, in order:

Calculating dependencies... done!
[ebuild     U  ] x11-apps/mesa-progs-8.2.0 [8.1.0] USE="-egl -gles1 -gles2" 0 kB

Total: 1 package (1 upgrade), Size of downloads: 0 kB

Would you like to merge these packages? [Yes/No] y

>>> Verifying ebuild manifests

>>> Emerging (1 of 1) x11-apps/mesa-progs-8.2.0
 * mesa-demos-8.2.0.tar.bz2 SHA256 SHA512 WHIRLPOOL size ;-) ...                                                                                      [ ok ]
>>> Unpacking source...
>>> Unpacking mesa-demos-8.2.0.tar.bz2 to /var/tmp/portage/x11-apps/mesa-progs-8.2.0/work
>>> Source unpacked in /var/tmp/portage/x11-apps/mesa-progs-8.2.0/work
>>> Preparing source in /var/tmp/portage/x11-apps/mesa-progs-8.2.0/work/mesa-demos-8.2.0 ...
 * Running eautoreconf in '/var/tmp/portage/x11-apps/mesa-progs-8.2.0/work/mesa-demos-8.2.0' ...
 * Running libtoolize --install --copy --force --automake ...                                                                                         [ ok ]
 * Running aclocal -I m4 ...                                                                                                                          [ ok ]
 * Running autoconf ...                                                                                                                               [ ok ]
 * Running automake --add-missing --copy --foreign --force-missing ...                                                                                [ ok ]
 * Running elibtoolize in: mesa-demos-8.2.0/
 *   Applying portage/1.2.0 patch ...
 *   Applying sed/1.5.6 patch ...
 *   Applying as-needed/2.4.2 patch ...
 *   Applying target-nm/2.4.2 patch ...
>>> Source prepared.
>>> Configuring source in /var/tmp/portage/x11-apps/mesa-progs-8.2.0/work/mesa-demos-8.2.0 ...
>>> Source configured.
>>> Compiling source in /var/tmp/portage/x11-apps/mesa-progs-8.2.0/work/mesa-demos-8.2.0 ...
make -j5 'LDLIBS=-lX11 -lGL' src/xdemos/glxinfo
x86_64-pc-linux-gnu-gcc -march=corei7 -O2 -pipe  -Wl,-O1 -Wl,--sort-common -Wl,--as-needed  src/xdemos/glxinfo.c  -lX11 -lGL -o src/xdemos/glxinfo
/var/tmp/portage/x11-apps/mesa-progs-8.2.0/temp/ccxFcAEg.o: In function `print_visual_attribs_verbose':
glxinfo.c:(.text+0x81e): undefined reference to `bitmask_to_string'
glxinfo.c:(.text+0x961): undefined reference to `bitmask_to_string'
/var/tmp/portage/x11-apps/mesa-progs-8.2.0/temp/ccxFcAEg.o: In function `create_context_flags.constprop.2':
glxinfo.c:(.text+0xd0d): undefined reference to `extension_supported'
/var/tmp/portage/x11-apps/mesa-progs-8.2.0/temp/ccxFcAEg.o: In function `create_context_with_config':
glxinfo.c:(.text+0xdec): undefined reference to `extension_supported'
/var/tmp/portage/x11-apps/mesa-progs-8.2.0/temp/ccxFcAEg.o: In function `print_screen_info':
glxinfo.c:(.text+0x1414): undefined reference to `print_extension_list'
glxinfo.c:(.text+0x1456): undefined reference to `print_extension_list'
glxinfo.c:(.text+0x148a): undefined reference to `print_extension_list'
glxinfo.c:(.text+0x1554): undefined reference to `print_extension_list'
glxinfo.c:(.text+0x15b1): undefined reference to `build_core_profile_extension_list'
glxinfo.c:(.text+0x1652): undefined reference to `profile_mask_string'
glxinfo.c:(.text+0x16e9): undefined reference to `print_limits'
glxinfo.c:(.text+0x1862): undefined reference to `context_flags_string'
collect2: error: ld returned 1 exit status
<builtin>: recipe for target 'src/xdemos/glxinfo' failed
make: *** [src/xdemos/glxinfo] Error 1
 * ERROR: x11-apps/mesa-progs-8.2.0 failed (compile phase):
 *   emake failed
 *
 * If you need support, post the output of `emerge --info '=x11-apps/mesa-progs-8.2.0'`,
 * the complete build log and the output of `emerge -pqv '=x11-apps/mesa-progs-8.2.0'`.
 * The complete build log is located at '/var/tmp/portage/x11-apps/mesa-progs-8.2.0/temp/build.log'.
 * The ebuild environment file is located at '/var/tmp/portage/x11-apps/mesa-progs-8.2.0/temp/environment'.
 * Working directory: '/var/tmp/portage/x11-apps/mesa-progs-8.2.0/work/mesa-demos-8.2.0'
 * S: '/var/tmp/portage/x11-apps/mesa-progs-8.2.0/work/mesa-demos-8.2.0'

>>> Failed to emerge x11-apps/mesa-progs-8.2.0, Log file:

>>>  '/var/tmp/portage/x11-apps/mesa-progs-8.2.0/temp/build.log'

 * Messages for package x11-apps/mesa-progs-8.2.0:

 * ERROR: x11-apps/mesa-progs-8.2.0 failed (compile phase):
 *   emake failed
 *
 * If you need support, post the output of `emerge --info '=x11-apps/mesa-progs-8.2.0'`,
 * the complete build log and the output of `emerge -pqv '=x11-apps/mesa-progs-8.2.0'`.
 * The complete build log is located at '/var/tmp/portage/x11-apps/mesa-progs-8.2.0/temp/build.log'.
 * The ebuild environment file is located at '/var/tmp/portage/x11-apps/mesa-progs-8.2.0/temp/environment'.
 * Working directory: '/var/tmp/portage/x11-apps/mesa-progs-8.2.0/work/mesa-demos-8.2.0'
 * S: '/var/tmp/portage/x11-apps/mesa-progs-8.2.0/work/mesa-demos-8.2.0'