updated for version 7.4.499

Problem:    substitute() can be slow with long strings.
Solution:   Store a pointer to the end, instead of calling strlen() every
	    time. (Ozaki Kiichi)

src/eval.c

@@ -25076,6 +25076,7 @@ do_string_sub(str, pat, sub, flags)
     int		i;
     int		do_all;
     char_u	*tail;
+    char_u	*end;
     garray_T	ga;
     char_u	*ret;
     char_u	*save_cpo;
@@ -25094,6 +25095,7 @@ do_string_sub(str, pat, sub, flags)
     if (regmatch.regprog != NULL)
     {
 	tail = str;
+	end = str + STRLEN(str);
 	while (vim_regexec_nl(&regmatch, str, (colnr_T)(tail - str)))
 	{
 	    /* Skip empty match except for first match. */
@@ -25120,7 +25122,7 @@ do_string_sub(str, pat, sub, flags)
 	     * - The text after the match.
 	     */
 	    sublen = vim_regsub(&regmatch, sub, tail, FALSE, TRUE, FALSE);
-	    if (ga_grow(&ga, (int)(STRLEN(tail) + sublen -
+	    if (ga_grow(&ga, (int)((end - tail) + sublen -
 			    (regmatch.endp[0] - regmatch.startp[0]))) == FAIL)
 	    {
 		ga_clear(&ga);

src/version.c

@@ -741,6 +741,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    499,
 /**/
     498,
 /**/