Better late than never: document that the GiST API changed in 8.0 in the

"incompatibilities" section of the release notes.

doc/src/sgml/release.sgml

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-$PostgreSQL: pgsql/doc/src/sgml/release.sgml,v 1.326 2005/02/02 18:16:13 momjian Exp $
+$PostgreSQL: pgsql/doc/src/sgml/release.sgml,v 1.327 2005/02/06 22:31:50 neilc Exp $
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 <appendix id="release">
@@ -467,6 +467,15 @@ typedefs (Michael)</para></listitem>
       </para>
      </listitem>
 
+     <listitem>
+      <para>
+       The API for user-defined GiST indexes has been changed. The
+       Union and PickSplit methods are now passed a pointer to a
+       special <structname>GistEntryVector</structname> structure,
+       rather than a <type>bytea</type>.
+      </para>
+     </listitem>
+
     </itemizedlist>
    </para>
   </sect2>