doc/changes.src: Describe changes

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
diff --git a/doc/changes.src b/doc/changes.src
index 844274a..a6a54f1 100644
--- a/doc/changes.src
+++ b/doc/changes.src
@@ -18,6 +18,10 @@
 
 \b Fix typo in documentation.
 
+\b Compound context local preprocessor single line macro identifiers
+  were not expanded early enough and as result lead to unresolved
+  symbols.
+
 
 \S{cl-2.09.01} Version 2.09.01