So I figured it out based on: https://lists.gnu.org/archive/html/lilypond-user/2016-07/msg00266.html
Not an unreasonable solution, but I still don't quite understand the underlying issue. Thanks From: David Santamauro <david.santama...@gmail.com> Date: Tuesday, March 22, 2022 at 8:36 AM To: lilypond-user@gnu.org <lilypond-user@gnu.org> Cc: GMAIL <david.santama...@gmail.com> Subject: Cross-staff glissando with crescendo and dynamics Hi, I'm not understanding the warnings I'm getting with the following snippet. I've included a possible work-around that is musically identical, but visually unappealing: %%%%%% \version "2.22.2" \include "english.ly" \score { \new PianoStaff \with { instrumentName = "Harp" } << \new Staff = "s_harp_upper" { \relative c'' { \clef "treble" s1 | s4 r4 r2 | % work around without warnings R1*2 } } \new Staff = "s_harp_lower" { \relative c { \clef "bass" f,1\p\glissando\< \change Staff = "s_harp_upper" bf'''4\!\mp \change Staff = "s_harp_lower" r4 r2 % work around without warnings f,,,1\p\glissando\< \clef "treble" bf'''4\!\mp r4 r2 } } >> } %%%%%% For the cross-staff I get 4 of these: programming error: My pure_y_common is a VerticalAlignment, which might contain several staves. continuing, cross fingers Can someone explain what those warnings mean and how to code the cross-staff gliss with dynamics and crescendo. correctly? Thanks