glibc 2.22 --- Hard freeze. Test your machines.

[Joseph Myers]

I've tracked the sort-test.sh intermittent failures to:

commit f13c2a8dff2329c6692a80176262ceaaf8a6f74e
Author: Leonhard Holz <leonhard.holz@web.de>
Date:   Tue May 12 11:37:52 2015 +0200

    Improve strcoll with strdiff.
    
    This patch improves strcoll hot case by finding first byte that
    mismatches. That is in likely case enough to determine comparison
    result.

See details and deterministic reproducer in bug 18589.  This is a 
regression from 2.21, though it may not need to block the release.

-- 
Joseph S. Myers
joseph@codesourcery.com