RemoveEmptyRythmicStaffContext

[pr . pa]

An Error appears when i want to hide a line (s1).

Using Linux with lilypond 2.8.5

error:
programming error: system with empty extent
Calculating page breaks...
programming error: Improbable offset for stencil: inf staff space
Setting to zero.
continuing, cross fingers

code:
upper = \relative c'
        {       \override Staff.NoteHead  #'style = #'slash
                d1\break
                s1\break
                a
        }
\score  {
                <<      
                \new RhythmicStaff {
                <<      
                        \upper
                >>}
                >>
\layout {       \context {      \Score
                                \remove "Bar_number_engraver"}
                \context {
                        \RemoveEmptyStaffContext}
                \context {
                        \Staff
                        \override VerticalAxisGroup #'remove-first = ##t}
                \context {
                        \RemoveEmptyRhythmicStaffContext}
                }
}