Severity: minor

1. Launch Emacs, clear the scratch buffer if it's not empty.

2. Type SPC.

3. Press C-M-i. See a bunch of menu entries (with spaces) as completions
(this is likely related to bug#16646).

Screenshot attached.

4. Add more spaces, press C-M-i again, see the list narrowed to
just the items that have so many spaces in them.

In GNU Emacs 24.3.50.6 (x86_64-unknown-linux-gnu, GTK+ Version 3.8.6)
 of 2014-02-06 on axl
Repository revision: 116279 dgutov@yandex.ru-20140206012238-a9potswcfgbv2qq2
Windowing system distributor `The X.Org Foundation', version 11.0.11405000
System Description:	Ubuntu 13.10