Easy heads: only access 'note-names vector if length > pitch-notename.

diff --git a/scm/output-lib.scm b/scm/output-lib.scm
index 8c34f01371e555bfbd16ac6278080ad07e05fb1d..a7ba96b58916f32fb7e3fcbbe27f46013562368c 100644 (file)
--- a/scm/output-lib.scm
+++ b/scm/output-lib.scm
@@ -140,7 +140,8 @@ and duration-log @var{log}."
         (pitch (ly:event-property (event-cause grob) 'pitch))
         (pitch-index (ly:pitch-notename pitch))
         (note-names (ly:grob-property grob 'note-names))
-        (pitch-string (if (vector? note-names)
+        (pitch-string (if (and (vector? note-names)
+                               (> (vector-length note-names) pitch-index))
                           (vector-ref note-names pitch-index)
                           (string
                            (integer->char