diff --git a/hash/doc/changes.qbk b/hash/doc/changes.qbk
index 7a56d38..4d0515a 100644
--- a/hash/doc/changes.qbk
+++ b/hash/doc/changes.qbk
@@ -65,4 +65,9 @@
   In Visual C++, always use C99 float functions for `long double` and `float` as
   the C++ overloads aren't always availables.
 
+[h2 Boost 1.38.0]
+
+* Changed the warnings in the deprecated headers from 1.34.0 to errors. These
+  will be removed in a future version of Boost.
+
 [endsect]