Reading Portage settings ..
Building database (/var/cache/eix) ..
 “gentoo” /usr/portage/ (cache: metadata-flat)
Reading 50%terminate called after throwing an instance of ‘std::out_of_range’
This is a bug in eix which has already been fixed in 0.13.5 version. So all you have to do is to update to that version (it’s still masked).
ACCEPT_KEYWORDS=”~x86″ emerge =eix-0.13.5 -av
In case you want to patch your version by yourself patch is avaible here.