diff --git a/7.3.703 b/7.3.703
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@@ -0,0 +1,97 @@
+To: vim_dev@googlegroups.com
+Subject: Patch 7.3.703
+Fcc: outbox
+From: Bram Moolenaar <Bram@moolenaar.net>
+Mime-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+------------
+
+Patch 7.3.703
+Problem:    When 'undofile' is reset the hash is computed unnecessarily.
+Solution:   Only compute the hash when the option was set. (Christian Brabandt)
+Files:      src/option.c
+
+
+*** ../vim-7.3.702/src/option.c	2012-10-21 00:10:29.000000000 +0200
+--- src/option.c	2012-10-21 03:42:10.000000000 +0200
+***************
+*** 7573,7596 ****
+      /* 'undofile' */
+      else if ((int *)varp == &curbuf->b_p_udf || (int *)varp == &p_udf)
+      {
+! 	char_u	hash[UNDO_HASH_SIZE];
+! 	buf_T	*save_curbuf = curbuf;
+! 
+! 	for (curbuf = firstbuf; curbuf != NULL; curbuf = curbuf->b_next)
+  	{
+! 	    /* When 'undofile' is set globally: for every buffer, otherwise
+! 	     * only for the current buffer: Try to read in the undofile, if
+! 	     * one exists and the buffer wasn't changed and the buffer was
+! 	     * loaded. */
+! 	    if ((curbuf == save_curbuf
+! 				|| (opt_flags & OPT_GLOBAL) || opt_flags == 0)
+! 		    && !curbufIsChanged() && curbuf->b_ml.ml_mfp != NULL)
+  	    {
+! 		u_compute_hash(hash);
+! 		u_read_undo(NULL, hash, curbuf->b_fname);
+  	    }
+  	}
+- 	curbuf = save_curbuf;
+      }
+  #endif
+  
+--- 7573,7602 ----
+      /* 'undofile' */
+      else if ((int *)varp == &curbuf->b_p_udf || (int *)varp == &p_udf)
+      {
+! 	/* Only take action when the option was set. When reset we do not
+! 	 * delete the undo file, the option may be set again without making
+! 	 * any changes in between. */
+! 	if (curbuf->b_p_udf || p_udf)
+  	{
+! 	    char_u	hash[UNDO_HASH_SIZE];
+! 	    buf_T	*save_curbuf = curbuf;
+! 
+! 	    for (curbuf = firstbuf; curbuf != NULL; curbuf = curbuf->b_next)
+  	    {
+! 		/* When 'undofile' is set globally: for every buffer, otherwise
+! 		 * only for the current buffer: Try to read in the undofile,
+! 		 * if one exists, the buffer wasn't changed and the buffer was
+! 		 * loaded */
+! 		if ((curbuf == save_curbuf
+! 				|| (opt_flags & OPT_GLOBAL) || opt_flags == 0)
+! 			&& !curbufIsChanged() && curbuf->b_ml.ml_mfp != NULL)
+! 		{
+! 		    u_compute_hash(hash);
+! 		    u_read_undo(NULL, hash, curbuf->b_fname);
+! 		}
+  	    }
++ 	    curbuf = save_curbuf;
+  	}
+      }
+  #endif
+  
+*** ../vim-7.3.702/src/version.c	2012-10-21 02:41:04.000000000 +0200
+--- src/version.c	2012-10-21 03:43:29.000000000 +0200
+***************
+*** 721,722 ****
+--- 721,724 ----
+  {   /* Add new patch number below this line */
++ /**/
++     703,
+  /**/
+
+-- 
+Scientists decoded the first message from an alien civilization:
+        SIMPLY SEND 6 TIMES 10 TO THE 50 ATOMS OF HYDROGEN TO THE STAR
+SYSTEM AT THE TOP OF THE LIST, CROSS OFF THAT STAR SYSTEM, THEN PUT
+YOUR STAR SYSTEM AT THE BOTTOM OF THE LIST AND SEND IT TO 100 OTHER
+STAR SYSTEMS.  WITHIN ONE TENTH GALACTIC ROTATION YOU WILL RECEIVE
+ENOUGH HYDROGREN TO POWER YOUR CIVILIZATION UNTIL ENTROPY REACHES ITS
+MAXIMUM!  IT REALLY WORKS!
+
+ /// Bram Moolenaar -- Bram@Moolenaar.net -- http://www.Moolenaar.net   \\\
+///        sponsor Vim, vote for features -- http://www.Vim.org/sponsor/ \\\
+\\\  an exciting new programming language -- http://www.Zimbu.org        ///
+ \\\            help me help AIDS victims -- http://ICCF-Holland.org    ///