PROJECT_COMPAT_VERSION
----------------------

.. versionadded:: 4.1

.. note::

  Experimental. Gated by ``CMAKE_EXPERIMENTAL_EXPORT_PACKAGE_INFO``.

Value given to the ``COMPAT_VERSION`` option of the most recent call to the
:command:`project` command, if any. To obtain the compatibility version of the
top level project, see the :variable:`CMAKE_PROJECT_COMPAT_VERSION` variable.
