--- a/src/insexpand.c
+++ b/src/insexpand.c
@@ -3040,6 +3040,43 @@ ins_compl_update_sequence_numbers(void)
     }
 }
 
+    static int
+info_add_completion_info(list_T *li)
+{
+    compl_T	*match;
+
+    if (compl_first_match == NULL)
+	return OK;
+
+    // Skip the element with the CP_ORIGINAL_TEXT flag at the beginning, in case of
+    // forward completion, or at the end, in case of backward completion.
+    match = compl_dir_forward()
+	    ? compl_first_match->cp_next : compl_first_match->cp_prev->cp_prev;
+    while (match != NULL && !match_at_original_text(match))
+    {
+	dict_T *di = dict_alloc();
+
+	if (di == NULL)
+	    return FAIL;
+	if (list_append_dict(li, di) == FAIL)
+	    return FAIL;
+	dict_add_string(di, "word", match->cp_str);
+	dict_add_string(di, "abbr", match->cp_text[CPT_ABBR]);
+	dict_add_string(di, "menu", match->cp_text[CPT_MENU]);
+	dict_add_string(di, "kind", match->cp_text[CPT_KIND]);
+	dict_add_string(di, "info", match->cp_text[CPT_INFO]);
+	if (match->cp_user_data.v_type == VAR_UNKNOWN)
+	    // Add an empty string for backwards compatibility
+	    dict_add_string(di, "user_data", (char_u *)"");
+	else
+	    dict_add_tv(di, "user_data", &match->cp_user_data);
+
+	match = compl_dir_forward() ? match->cp_next : match->cp_prev;
+    }
+
+    return OK;
+}
+
 /*
  * Get complete information
  */
@@ -3088,41 +3125,13 @@ get_complete_info(list_T *what_list, dic
     if (ret == OK && (what_flag & CI_WHAT_ITEMS))
     {
 	list_T	    *li;
-	dict_T	    *di;
-	compl_T     *match;
 
 	li = list_alloc();
 	if (li == NULL)
 	    return;
 	ret = dict_add_list(retdict, "items", li);
-	if (ret == OK && compl_first_match != NULL)
-	{
-	    match = compl_first_match;
-	    do
-	    {
-		if (!match_at_original_text(match))
-		{
-		    di = dict_alloc();
-		    if (di == NULL)
-			return;
-		    ret = list_append_dict(li, di);
-		    if (ret != OK)
-			return;
-		    dict_add_string(di, "word", match->cp_str);
-		    dict_add_string(di, "abbr", match->cp_text[CPT_ABBR]);
-		    dict_add_string(di, "menu", match->cp_text[CPT_MENU]);
-		    dict_add_string(di, "kind", match->cp_text[CPT_KIND]);
-		    dict_add_string(di, "info", match->cp_text[CPT_INFO]);
-		    if (match->cp_user_data.v_type == VAR_UNKNOWN)
-			// Add an empty string for backwards compatibility
-			dict_add_string(di, "user_data", (char_u *)"");
-		    else
-			dict_add_tv(di, "user_data", &match->cp_user_data);
-		}
-		match = match->cp_next;
-	    }
-	    while (match != NULL && !is_first_match(match));
-	}
+	if (ret == OK)
+	    ret = info_add_completion_info(li);
     }
 
     if (ret == OK && (what_flag & CI_WHAT_SELECTED))

--- a/src/testdir/test_ins_complete.vim
+++ b/src/testdir/test_ins_complete.vim
@@ -2243,5 +2243,43 @@ func Test_ins_complete_popup_position()
   call StopVimInTerminal(buf)
 endfunc
 
+func GetCompleteInfo()
+  let g:compl_info = complete_info()
+  return ''
+endfunc
+
+func Test_complete_info_index()
+  new
+  call setline(1, ["aaa", "bbb", "ccc", "ddd", "eee", "fff"])
+  inoremap <buffer><F5> <C-R>=GetCompleteInfo()<CR>
+
+  " Ensure 'index' in complete_info() is coherent with the 'items' array.
+
+  set completeopt=menu,preview
+  " Search forward.
+  call feedkeys("Go\<C-X>\<C-N>\<F5>\<Esc>_dd", 'tx')
+  call assert_equal("aaa", g:compl_info['items'][g:compl_info['selected']]['word'])
+  call feedkeys("Go\<C-X>\<C-N>\<C-N>\<F5>\<Esc>_dd", 'tx')
+  call assert_equal("bbb", g:compl_info['items'][g:compl_info['selected']]['word'])
+
+  " Search backward.
+  call feedkeys("Go\<C-X>\<C-P>\<F5>\<Esc>_dd", 'tx')
+  call assert_equal("fff", g:compl_info['items'][g:compl_info['selected']]['word'])
+  call feedkeys("Go\<C-X>\<C-P>\<C-P>\<F5>\<Esc>_dd", 'tx')
+  call assert_equal("eee", g:compl_info['items'][g:compl_info['selected']]['word'])
+
+  " Add 'noselect', check that 'selected' is -1 when nothing is selected.
+  set completeopt+=noselect
+  " Search forward.
+  call feedkeys("Go\<C-X>\<C-N>\<F5>\<Esc>_dd", 'tx')
+  call assert_equal(-1, g:compl_info['selected'])
+
+  " Search backward.
+  call feedkeys("Go\<C-X>\<C-P>\<F5>\<Esc>_dd", 'tx')
+  call assert_equal(-1, g:compl_info['selected'])
+
+  set completeopt&
+  bwipe!
+endfunc
 
 " vim: shiftwidth=2 sts=2 expandtab

--- a/src/version.c
+++ b/src/version.c
@@ -705,6 +705,8 @@ static char *(features[]) =
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    2018,
+/**/
     2017,
 /**/
     2016,