On 2018-01-03, at 17:24, Alan Mackenzie <acm@muc.de> wrote:

> These things are tricky to test properly.  ;-)

Fair enough.  But we should at least try to prepare a regression test
when a bug pops its head. ;-)

I attach a set of two patches wit such a test.  WDYT?

Best,

-- 
Marcin Borkowski
http://mbork.pl