Neil's patch was supposed to remove this, too.

src/backend/utils/error/format.c

@@ -1,36 +0,0 @@
-/*-------------------------------------------------------------------------
- *
- * format.c
- *	  a wrapper around code that does what vsprintf does.
- *
- * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
- * Portions Copyright (c) 1994, Regents of the University of California
- *
- *
- * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/utils/error/Attic/format.c,v 1.17 2002/06/20 20:29:39 momjian Exp $
- *
- *-------------------------------------------------------------------------
- */
-#include "postgres.h"
-
-#define FormMaxSize		1024
-#define FormMinSize		(FormMaxSize / 8)
-
-static char FormBuf[FormMaxSize];
-
-
-/* ----------------
- *		vararg_format
- * ----------------
- */
-char *
-vararg_format(const char *fmt,...)
-{
-	va_list		args;
-
-	va_start(args, fmt);
-	vsnprintf(FormBuf, FormMaxSize - 1, fmt, args);
-	va_end(args);
-	return FormBuf;
-}