Comment #2 on issue 2010 by [email protected]: \lyricsto may turn into a voice-mangling zombie when both parents die at the same time
http://code.google.com/p/lilypond/issues/detail?id=2010
The problem appears to be that the Lyric_combine_music_iterator is kept alive too long. With the above example, its last call to process happens at Moment 2/1 respective to its start, quite too late to resume the outer music.
Also when the music terminates, it takes down the associatedVoiceContext, and then the subordinate Lyrics iterator starts looking for a different voice of that name to attach to. This is all a rather ugly mess with regard to timing and interaction.
