With commit 5761a1a3939e23d8e8c725241dd9398a12f191b0

1. emacs -Q
2. M-x icomplete-mode RET
3. M-x icomplete-mode

After typing last "e" there are error:

Error in post-command-hook (icomplete-post-command-hook):
(args-out-of-range -1 1)