On a stable system: # emerge -av1 dvipdfmx These are the packages that would be merged, in order: Calculating dependencies... done! [ebuild N ] app-text/texlive-core-2016-r5::gentoo USE="X luajittex -cjk -doc -source -tk -xetex" 0 KiB [ebuild N ] app-text/dvipdfmx-20110311-r1::gentoo 603 KiB [blocks B ] app-text/dvipdfmx ("app-text/dvipdfmx" is blocking app-text/texlive-core-2016-r5) Since app-text/texlive-core-2016-r5 is stable and blocks app-text/dvipdfmx, maybe it's time to remove dvipdfmx.
It's masked for removal.
dvipdfm was last-rited and removed in commit 54577498873ba6ae4dd13a744569fc783a63cacb.