It would help the debugging if you could provide an example file
that triggers this bug. If you don't want to send it to the full
list, please send a copy to the main authors of Lilypond, Han-Wen
and Jan (see
http://lilypond.org/stable/Documentation/topdocs/out-www/AUTHORS.html
for addresses).
I know you're already working on 1.7.x, so I don't know if bugs like
this are relevant anymore, but I thought I'd send it just in case. I
got the following error after a recent run of ly2dvi 1.6.6:
lilypond: ../flower/include/drul-array.hh:26: Real &
Drul_array::elem(Direction): Assertion `d==
