http://sourceware.org/gdb/current/onlinedocs/gdb/Index-Section-Format.html I hope that resolves Roland's doubts about the usefulness of parsing/outputting this section with eu-readelf.
It really doesn't have anything to do with the objection at all.
It was already useful BTW. We found out gdb was outputting bad/redundant CU indexes by inspecting the output produced by eu-readelf. Which Tom already fixed. http://sourceware.org/ml/gdb-patches/2011-04/msg00224.html
I never said you shouldn't write something to parse it. Obviously that is useful. I just said it did not belong in eu-readelf.