Comment 3 for bug 1681983

I blame pbr for this but not the part that you'd expect. By default, pbr will build both HTML and man page output [1], but this isn't documented anywhere. This is a nonsensical default, given that the vast majority of projects (_everything_ within the oslo tent, to start) don't need man pages. With the change Matt links to, Sphinx will now correctly fail when attempting to build man pages because there aren't any man pages to build.

I think that feature, more so than anything else, should be changed. This would probably necessitate a major version bump (as a breaking change) and changes in the projects that _do_ want man page output (specifying 'builders' or waiting for Sphinx 1.6 which allows you to specify multiple builders using the stock 'builder' configuration option [2])

[1] https://github.com/openstack-dev/pbr/blob/2.1.0/pbr/builddoc.py#L66
[2] https://github.com/sphinx-doc/sphinx/commit/2afa0b6627f7e5afb188d5a60c8c4767f6250774