Issues with ancient notation

[Cameron Horsburgh]

Hi folks,

I am getting programming errors on the following file which is based
on an example from the LSR:

%%%%%
\version "2.10.10"

\include "gregorian-init.ly"

\score {
  \context VaticanaVoice {
     {
       \[ a \episemInitium \pes b \flexa a \episemFinis \]
     }
  }
}
%%%%%

which results in:
...
Parsing...
Interpreting music... 
Preprocessing graphical objects...
programming error: adding reverse spring, setting to unit
continuing, cross fingers
programming error: adding reverse spring, setting to unit
continuing, cross fingers
...

and finishes successfully. I don't understand gregorian notation, so I
cannot say if the output is correct -- however, the ligatures in this
example don't seem to have been rendered.

Is this a bug, or is it nothing to worry about?

-- 

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Cameron Horsburgh

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