diff --git a/man/manual.docbook b/man/manual.docbook
index 3d588c973..16955395f 100644
--- a/man/manual.docbook
+++ b/man/manual.docbook
@@ -156,6 +156,14 @@ Checking path/file2.cpp...
           </listitem>
         </varlistentry>
 
+        <varlistentry>
+          <term>portability</term>
+
+          <listitem>
+            <para>portability warnings. 64-bit portability. code might work different on different compilers. etc.</para>
+          </listitem>
+        </varlistentry>
+
         <varlistentry>
           <term>information</term>