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+To: vim_dev@googlegroups.com
+Subject: Patch 7.3.851
+Fcc: outbox
+From: Bram Moolenaar <Bram@moolenaar.net>
+Mime-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+------------
+
+Patch 7.3.851
+Problem:    Using an empty pattern with :sort silently continues when there is
+	    no previous search pattern.
+Solution:   Give an error message.
+Files:	    src/ex_cmds.c
+
+
+*** ../vim-7.3.850/src/ex_cmds.c	2013-03-07 16:08:31.000000000 +0100
+--- src/ex_cmds.c	2013-03-07 16:25:28.000000000 +0100
+***************
+*** 415,422 ****
+  	    }
+  	    *s = NUL;
+  	    /* Use last search pattern if sort pattern is empty. */
+! 	    if (s == p + 1 && last_search_pat() != NULL)
+  		regmatch.regprog = vim_regcomp(last_search_pat(), RE_MAGIC);
+  	    else
+  		regmatch.regprog = vim_regcomp(p + 1, RE_MAGIC);
+  	    if (regmatch.regprog == NULL)
+--- 415,429 ----
+  	    }
+  	    *s = NUL;
+  	    /* Use last search pattern if sort pattern is empty. */
+! 	    if (s == p + 1)
+! 	    {
+! 		if (last_search_pat() == NULL)
+! 		{
+! 		    EMSG(_(e_noprevre));
+! 		    goto sortend;
+! 		}
+  		regmatch.regprog = vim_regcomp(last_search_pat(), RE_MAGIC);
++ 	    }
+  	    else
+  		regmatch.regprog = vim_regcomp(p + 1, RE_MAGIC);
+  	    if (regmatch.regprog == NULL)
+*** ../vim-7.3.850/src/version.c	2013-03-07 16:32:49.000000000 +0100
+--- src/version.c	2013-03-07 16:38:49.000000000 +0100
+***************
+*** 730,731 ****
+--- 730,733 ----
+  {   /* Add new patch number below this line */
++ /**/
++     851,
+  /**/
+
+-- 
+This planet has -- or rather had -- a problem, which was this: most
+of the people living on it were unhappy for pretty much of the time.
+Many solutions were suggested for this problem, but most of these
+were largely concerned with the movements of small green pieces of
+paper, which is odd because on the whole it wasn't the small green
+pieces of paper that were unhappy.
+		-- Douglas Adams, "The Hitchhiker's Guide to the Galaxy"
+
+ /// 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    ///