Fix #767.

[lilypond.git] / lily / music-sequence.cc

diff --git a/lily/music-sequence.cc b/lily/music-sequence.cc
index 906419405fed1cdf41b3bc22818eeaf7f88cce81..70a2eaa862c9c246dac7bc183511fa45ec1a4f65 100644 (file)
--- a/lily/music-sequence.cc
+++ b/lily/music-sequence.cc
@@ -3,14 +3,15 @@
 
   source file of the GNU LilyPond music typesetter
 
-  (c) 1998--2005 Han-Wen Nienhuys <hanwen@cs.uu.nl>
+  (c) 1998--2009 Han-Wen Nienhuys <hanwen@xs4all.nl>
 */
 
+#include "music-sequence.hh"
+
 #include "warn.hh"
 #include "program-option.hh"
-#include "pitch.hh"
+#include "music.hh"
 #include "input.hh"
-#include "music-sequence.hh"
 
 void
 transpose_music_list (SCM lst, Pitch rq)
@@ -47,8 +48,13 @@ Music_sequence::maximum_length (SCM l)
   for (SCM s = l; scm_is_pair (s); s = scm_cdr (s))
     {
       Music *m = unsmob_music (scm_car (s));
-      Moment l = m->get_length ();
-      dur = max (dur, l);
+      if (!m)
+       programming_error ("Music sequence should have music elements");
+      else
+       {
+         Moment l = m->get_length ();
+         dur = max (dur, l);
+       }
     }
 
   return dur;