CMP0001
-------

.. |REMOVED_IN_CMAKE_VERSION| replace:: 4.0
.. include:: REMOVED_PROLOGUE.txt

``CMAKE_BACKWARDS_COMPATIBILITY`` should no longer be used.

The behavior is to check ``CMAKE_BACKWARDS_COMPATIBILITY`` and present
it to the user.  The ``NEW`` behavior is to ignore
``CMAKE_BACKWARDS_COMPATIBILITY`` completely.

In CMake 2.4 and below the variable ``CMAKE_BACKWARDS_COMPATIBILITY`` was
used to request compatibility with earlier versions of CMake.  In
CMake 2.6 and above all compatibility issues are handled by policies
and the :command:`cmake_policy` command.  However, CMake must still check
``CMAKE_BACKWARDS_COMPATIBILITY`` for projects written for CMake 2.4 and
below.

.. |INTRODUCED_IN_CMAKE_VERSION| replace:: 2.6.0
.. |WARNED_OR_DID_NOT_WARN| replace:: warned
.. include:: REMOVED_EPILOGUE.txt