The following MWE works under 2.20.0 but crashes LilyPond under 2.21.1.
\version "2.20.0"
\layout {
\context {
\name GlobalRests
\type Engraver_group
\consists Multi_measure_rest_engraver
}
\context {
\name GlobalContext
\type Engraver_group
\accepts GlobalRests
}
\context {
\Score
\accepts GlobalContext
}
}
\new Score
<<
\new GlobalContext
{
\new GlobalRests { R1 }
}
\new Staff { \time 4/4 R1 }
>>
### END ###
GNU LilyPond 2.20.0
Processing `illustration.ly'
Parsing...
Interpreting music...
Preprocessing graphical objects...
Finding the ideal number of pages...
Fitting music on 1 page...
Drawing systems...
Layout output to `/var/folders/0k/3dbjvd1548b0wkstx2lyb60w0000gn/T//lilypond-kmhqj8'...
Converting to `illustration.pdf'...
Deleting `/var/folders/0k/3dbjvd1548b0wkstx2lyb60w0000gn/T//lilypond-kmhqj8'...
Success: compilation successfully completed
### CRASHES UNDER 2.21.1 ###
\version "2.21.1"
\layout {
\context {
\name GlobalRests
\type Engraver_group
\consists Multi_measure_rest_engraver
}
\context {
\name GlobalContext
\type Engraver_group
\accepts GlobalRests
}
\context {
\Score
\accepts GlobalContext
}
}
\new Score
<<
\new GlobalContext
{
\new GlobalRests { R1 }
}
\new Staff { \time 4/4 R1 }
>>
### END ###
GNU LilyPond 2.21.1
Processing `illustration.ly'
Parsing...
Interpreting music...
Preprocessing graphical objects... < halt >
The workaround appears to be to use 2.20.0 until the 2.21.1 bug can be tracked down.
Trevor.
--