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+To: vim_dev@googlegroups.com
+Subject: Patch 7.3.689
+Fcc: outbox
+From: Bram Moolenaar <Bram@moolenaar.net>
+Mime-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+------------
+
+Patch 7.3.689
+Problem:    MzScheme and Lua may use a NULL string.
+Solution:   Use an empty string instead of NULL. (Yukihiro Nakadaira)
+Files:      src/if_lua.c, src/if_mzsch.c
+
+
+*** ../vim-7.3.688/src/if_lua.c	2012-06-29 12:54:32.000000000 +0200
+--- src/if_lua.c	2012-10-14 03:33:32.000000000 +0200
+***************
+*** 464,470 ****
+      switch (tv->v_type)
+      {
+  	case VAR_STRING:
+! 	    lua_pushstring(L, (char *) tv->vval.v_string);
+  	    break;
+  	case VAR_NUMBER:
+  	    lua_pushinteger(L, (int) tv->vval.v_number);
+--- 464,471 ----
+      switch (tv->v_type)
+      {
+  	case VAR_STRING:
+! 	    lua_pushstring(L, tv->vval.v_string == NULL
+! 					    ? "" : (char *)tv->vval.v_string);
+  	    break;
+  	case VAR_NUMBER:
+  	    lua_pushinteger(L, (int) tv->vval.v_number);
+*** ../vim-7.3.688/src/if_mzsch.c	2012-02-12 01:55:50.000000000 +0100
+--- src/if_mzsch.c	2012-10-14 03:33:32.000000000 +0200
+***************
+*** 2649,2655 ****
+  	new_value = FALSE;
+      else if (vim_value->v_type == VAR_STRING)
+      {
+! 	result = scheme_make_string((char *)vim_value->vval.v_string);
+  	MZ_GC_CHECK();
+      }
+      else if (vim_value->v_type == VAR_NUMBER)
+--- 2649,2656 ----
+  	new_value = FALSE;
+      else if (vim_value->v_type == VAR_STRING)
+      {
+! 	result = scheme_make_string(vim_value->vval.v_string == NULL
+! 				    ? "" : (char *)vim_value->vval.v_string);
+  	MZ_GC_CHECK();
+      }
+      else if (vim_value->v_type == VAR_NUMBER)
+*** ../vim-7.3.688/src/version.c	2012-10-14 03:22:49.000000000 +0200
+--- src/version.c	2012-10-14 03:33:49.000000000 +0200
+***************
+*** 721,722 ****
+--- 721,724 ----
+  {   /* Add new patch number below this line */
++ /**/
++     689,
+  /**/
+
+-- 
+Computers make very fast, very accurate, mistakes.
+
+ /// 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    ///