Github release tarballs are not supported by Ardour
This information applies to bundles automatically generated by
Ardour's program version is maintained using git-tags. Compiling Ardour depends
on `git describe` (a full git clone is needed for this) or alternatively a
version-file in the release-dist. Github cannot provide the latter and also
does not allow to inject a version-file during export archiving.
For further information see http://tracker.ardour.org/view.php?id=7328