diff --git a/include/abg-comparison.h b/include/abg-comparison.h
index 3acf067f..fa118c38 100644
--- a/include/abg-comparison.h
+++ b/include/abg-comparison.h
@@ -1106,7 +1106,7 @@ class base_diff;
 /// Convenience typedef for a shared pointer to base_diff.
 typedef shared_ptr<base_diff> base_diff_sptr;
 
-/// An abstraction of a diff between two instances of base_diff.
+/// An abstraction of a diff between two instances of class_decl::base_spec.
 class base_diff : public diff
 {
   struct priv;