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+To: vim_dev@googlegroups.com
+Subject: Patch 7.3.646
+Fcc: outbox
+From: Bram Moolenaar <Bram@moolenaar.net>
+Mime-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+------------
+
+Patch 7.3.646
+Problem:    When reloading a buffer the undo file becomes unusable unless ":w"
+	    is executed. (Dmitri Frank)
+Solution:   After reloading the buffer write the undo file. (Christian
+	    Brabandt)
+Files:	    src/fileio.c
+
+
+*** ../vim-7.3.645/src/fileio.c	2012-07-10 17:14:50.000000000 +0200
+--- src/fileio.c	2012-08-29 18:19:44.000000000 +0200
+***************
+*** 7060,7067 ****
+--- 7060,7082 ----
+      }
+  
+      if (reload)
++     {
+  	/* Reload the buffer. */
+  	buf_reload(buf, orig_mode);
++ #ifdef FEAT_PERSISTENT_UNDO
++ 	if (buf->b_p_udf && buf->b_ffname != NULL)
++ 	{
++ 	    char_u	    hash[UNDO_HASH_SIZE];
++ 	    buf_T	    *save_curbuf = curbuf;
++ 
++ 	    /* Any existing undo file is unusable, write it now. */
++ 	    curbuf = buf;
++ 	    u_compute_hash(hash);
++ 	    u_write_undo(NULL, FALSE, buf, hash);
++ 	    curbuf = save_curbuf;
++ 	}
++ #endif
++     }
+  
+  #ifdef FEAT_AUTOCMD
+      /* Trigger FileChangedShell when the file was changed in any way. */
+*** ../vim-7.3.645/src/version.c	2012-08-29 16:55:09.000000000 +0200
+--- src/version.c	2012-08-29 18:21:07.000000000 +0200
+***************
+*** 721,722 ****
+--- 721,724 ----
+  {   /* Add new patch number below this line */
++ /**/
++     646,
+  /**/
+
+-- 
+   An extraordinary TALL KNIGHT in all black (possibly John with Mike on his
+   shoulders) walks out from the dark trees.  He is extremely fierce and
+   gruesome countenance.  He walks towards KING ARTHUR and PATSY, who are
+   wazzing like mad.  (Salopian slang, meaning very scared.  almost to the
+   point of wetting oneself, e.g. before an important football match or
+   prior to a postering.  Salopian slang meaning a beating by the school
+   praeposters.  Sorry about the Salopian slant to this stage direction - Ed.)
+                 "Monty Python and the Holy Grail" PYTHON (MONTY) PICTURES LTD
+
+ /// 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    ///