Hi,

I found bug on display a popup window from auto-complete-mode. I attach two screenshot and init.el. Bug appear when global-linum-mode is on.

Commit e589765 bring this bug. I changed the line that seemed most appropriate. I not understand how it work, but this patch fix it:

--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -3434,6 +3434,7 @@ handle_stop (struct it *it)
   it->dpvec = NULL;
   it->current.dpvec_index = -1;
   handle_overlay_change_p = !it->ignore_overlay_strings_at_pos_p;
+  it->ignore_overlay_strings_at_pos_p = false;
   it->ellipsis_p = 0;
 
   /* Use face of preceding text for ellipsis (if invisible) */

Note, this patch do not break fix by e589765 (http://lists.gnu.org/archive/html/bug-gnu-emacs/2015-02/msg00075.html).

Screenshots also uploaded to the external server:
http://www.embddr.com/emacs-popup-good.png
http://www.embddr.com/emacs-popup-bad.png

Init.el:
(require 'package)
(add-to-list 'package-archives '("melpa" . "http://melpa.milkbox.net/packages/"))
(package-initialize)

(require 'auto-complete-config)
(auto-complete-mode t)
(ac-config-default)

(global-linum-mode t)


Nikolay Puzanov.