regex (-r) is the default Match algorithm for eix, it doesn't work on gfbsd: root@gfbsd ~ # eix apache regcomp(""): empty (sub)expression the other Match algorithms are working instead: eix -e eix -f eix -p
eix calls regcomp("") in a constructor: I think that "" should be a valid regular expression which should match every string. So it is somewhat strange that regcomp returns an error status for the argument "". In the current svn trunk of eix (presumably eix-0.8.4), I have written a manual test for the empty string before calling regcomp, so that no problems with eix should arise anymore. However, maybe the corresponding regcomp-function on gfbsd should be fixed anyway...
Patched in cvs without revbump, you only need to reinstall 0.8.3 and it should works