object db compiles
diff --git a/include/object-db.h b/include/object-db.h
index 7daa37c..207e0b3 100644
--- a/include/object-db.h
+++ b/include/object-db.h
@@ -35,7 +35,7 @@
 
   // size in terms of number of COs
   virtual int
-  size() = 0 const;
+  size() = 0;
 
 };