> l.56 \initial {\\}
Works for me with current texinfo.tex and the input below (to force
creating the \initial line). I don't doubt there was a bug in some
version of texinfo.tex in this regard, but I routinely run Texinfo
documents with \indexentries, so I doubt it existed for long. -k
--------------
\input texinfo
@setfilename backindex.info
@cindex \foo
@cindex bar
@printindex cp
@bye