X-Git-Url: https://git.donarmstrong.com/?a=blobdiff_plain;f=lily%2Fbook.cc;fp=lily%2Fbook.cc;h=bf324091041b73cc21650863fb18857036cb429b;hb=1b5f1825a6655583a6209fedd51b98f4865bb2cd;hp=8ba2aac9080432144e58aa035a70575871dd7b50;hpb=e96e340ad1d9ae9d40849c2f0fe26f963f52c522;p=lilypond.git

diff --git a/lily/book.cc b/lily/book.cc
index 8ba2aac908..bf32409104 100644
--- a/lily/book.cc
+++ b/lily/book.cc
@@ -107,7 +107,7 @@ Book::~Book ()
 
 
 SCM
-Book::mark_smob ()
+Book::mark_smob () const
 {
   if (paper_)
     scm_gc_mark (paper_->self_scm ());