If you encounter libtool blocking itself in an update: [blocks B ] =sys-devel/libtool-2*:1.5 ("=sys-devel/libtool-2*:1.5" is blocking sys-devel/libtool-2.4-r1) Update libtool independently before proceeding: # emerge --update libtool

read more: sys-devel/libtool-2*:1.5 is blocking sys-devel/libtool