patch 9.0.0046: reading past end of completion with duplicate match

Problem:    Reading past end of completion with duplicate match.
Solution:   Check string length

src/insexpand.c

@@ -786,7 +786,8 @@ ins_compl_add(
 	{
 	    if (!match_at_original_text(match)
 		    && STRNCMP(match->cp_str, str, len) == 0
-		    && match->cp_str[len] == NUL)
+		    && ((int)STRLEN(match->cp_str) <= len
+						 || match->cp_str[len] == NUL))
 		return NOTDONE;
 	    match = match->cp_next;
 	} while (match != NULL && !is_first_match(match));

src/testdir/test_ins_complete.vim

@@ -2112,5 +2112,15 @@ func Test_infercase_very_long_line()
   set noic noinfercase
 endfunc
 
+func Test_ins_complete_add()
+  " this was reading past the end of allocated memory
+  new
+  norm o
+  norm 7o€€
+  sil! norm o
+
+  bwipe!
+endfunc
+
 
 " vim: shiftwidth=2 sts=2 expandtab

src/version.c

@@ -735,6 +735,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    46,
 /**/
     45,
 /**/