texinfo.tex problem formatting index

[Arnold Robbins]

Hi.

I just saw a weird case where texinfo.tex put a blank page in
the middle of the index.  To reproduce:

        git clone https://github.com/arnoldrobbins/prepinfo
        cd prepinfo
        make

Look at the index in the PDF.

This is with the current texinfo.tex.

Please cc me on any responses, I'm not on the bug-texinfo list.

Thanks!

Arnold