48095c623f
While the prose clarifies this below, a quick glance at the docs can make one believe that `...3.10` has no sensible use. However, it is still useful to tell CMake 3.12 and up that at least 3.10 behavior is accepted.
70 lines
2.4 KiB
ReStructuredText
70 lines
2.4 KiB
ReStructuredText
cmake_minimum_required
|
|
----------------------
|
|
|
|
Require a minimum version of cmake.
|
|
|
|
.. code-block:: cmake
|
|
|
|
cmake_minimum_required(VERSION <min>[...<policy_max>] [FATAL_ERROR])
|
|
|
|
.. versionadded:: 3.12
|
|
The optional ``<policy_max>`` version behavior; ignored in older CMake.
|
|
|
|
Sets the minimum required version of cmake for a project.
|
|
Also updates the policy settings as explained below.
|
|
|
|
``<min>`` and the optional ``<policy_max>`` are each CMake versions of the
|
|
form ``major.minor[.patch[.tweak]]``, and the ``...`` is literal.
|
|
|
|
If the running version of CMake is lower than the ``<min>`` required
|
|
version it will stop processing the project and report an error.
|
|
The optional ``<policy_max>`` version, if specified, must be at least the
|
|
``<min>`` version and sets the `Policy Version`_.
|
|
If the running version of CMake is older than 3.12, the extra ``...``
|
|
dots will be seen as version component separators, resulting in the
|
|
``...<max>`` part being ignored and preserving the pre-3.12 behavior
|
|
of basing policies on ``<min>``.
|
|
|
|
This command will set the value of the
|
|
:variable:`CMAKE_MINIMUM_REQUIRED_VERSION` variable to ``<min>``.
|
|
|
|
The ``FATAL_ERROR`` option is accepted but ignored by CMake 2.6 and
|
|
higher. It should be specified so CMake versions 2.4 and lower fail
|
|
with an error instead of just a warning.
|
|
|
|
.. note::
|
|
Call the ``cmake_minimum_required()`` command at the beginning of
|
|
the top-level ``CMakeLists.txt`` file even before calling the
|
|
:command:`project` command. It is important to establish version
|
|
and policy settings before invoking other commands whose behavior
|
|
they may affect. See also policy :policy:`CMP0000`.
|
|
|
|
Calling ``cmake_minimum_required()`` inside a :command:`function`
|
|
limits some effects to the function scope when invoked. For example,
|
|
the :variable:`CMAKE_MINIMUM_REQUIRED_VERSION` variable won't be set
|
|
in the calling scope. Functions do not introduce their own policy
|
|
scope though, so policy settings of the caller *will* be affected
|
|
(see below). Due to this mix of things that do and do not affect the
|
|
calling scope, calling ``cmake_minimum_required()`` inside a function
|
|
is generally discouraged.
|
|
|
|
.. _`Policy Version`:
|
|
|
|
Policy Version
|
|
^^^^^^^^^^^^^^
|
|
|
|
``cmake_minimum_required(VERSION <min>[...<max>])`` implicitly invokes
|
|
|
|
.. code-block:: cmake
|
|
|
|
cmake_policy(VERSION <min>[...<max>])
|
|
|
|
.. include:: POLICY_VERSION.txt
|
|
|
|
.. include:: DEPRECATED_POLICY_VERSIONS.txt
|
|
|
|
See Also
|
|
^^^^^^^^
|
|
|
|
* :command:`cmake_policy`
|