Three versioning schemes are involved.
* Commercial non GPL releases are numbered MAJOR.MINOR on Adacore
  website.
* Development builds between MAJOR.MINOR and NEXTMAJOR.NEXTMINOR
  releases are numbered NEXTMAJOR.NEXTMINORw (w as wavefront).
* Every year, a tarball is distributed on http://libre.adacore.com
  with the current year as version number, and every header stripped
  from the paragraph granting the GCC Runtime Library Exception.
* Each Debian package is based on a GPL release, but numbered
  MAJOR.MINOR.YEAR in order to ease comparison with other versions.

Upstream history is visible on GitHub at https://github.com/AdaCore/gprbuild.
The version number is always visible in first line of ./configure.in.
Each GPL release is prepared in a branch named gpl-$YEAR.

The source package version in Debian is based on the year, and this
cannot be changed easily now.  However, we use this to select a
sensible Shared Object version.

The GPL-2017 was released between 17.2 and 18.0, but will use
16.1.2016 as soversion as long as there is no better reason to rename
the Debian library package.

 -- Nicolas Boulenguez <nicolas@debian.org>, Sat, 24 Jun 2017 20:25:34 +0200
