PowerDNS/pdns — pull request #991 by zeha (2013-09-04 10:03:41+00:00)
Title: Enable subdir-objects for automake-1.14

Fixes warnings about source files in subdirectories, without having
this option enabled.

Appears to work on Travis, which likely has automake 1.11. Can't vouch for even older versions.
(Also I don't 100% understand what this option changes.)