Re: Issue 1997 in lilypond: segfault in tablature-negative-fret.ly

[lilypond]

Comment #6 on issue 1997 by address@hidden: segfault in  
tablature-negative-fret.ly
http://code.google.com/p/lilypond/issues/detail?id=1997

address@hidden writes:

I have just brainlessly started looking at instances of unsmob* to see
where we might deal with unprotected pointers.

I find it somewhat disconcerting that stuff like struct
Side_position_interface keeps pointers to parent grobs, but is not
smobbified itself.

Does anybody have an idea what keeps parent grobs here alive and safe
from being garbage-collected until Side_position_interface does no
longer need them?