CMP0180

.. versionadded:: 3.31

:command:project always sets <PROJECT-NAME>_* as normal variables.

In CMake 3.29 and below, the :command:project command set :variable:<PROJECT-NAME>_SOURCE_DIR, :variable:<PROJECT-NAME>_BINARY_DIR, and :variable:<PROJECT-NAME>_IS_TOP_LEVEL as cache entries, but not as normal variables. CMake 3.30 started setting them as normal variables, but only if they are already set as normal variables. This was needed to preserve support for some :module:FetchContent use cases under policy :policy:CMP0169's NEW behavior, while also preserving behavior of nested directories that call :command:project with the same project name. See release notes for 3.30.3, 3.30.4, and 3.30.5 for details.

CMake 3.31 and later prefer to always set <PROJECT-NAME>_SOURCE_DIR, <PROJECT-NAME>_BINARY_DIR, and <PROJECT-NAME>_IS_TOP_LEVEL, as both cache entries and normal variables, regardless of what cache or normal variables already exist. This policy provides compatibility for projects that have not been updated to expect this behavior.

The OLD behavior for this policy will only set normal variables for <PROJECT-NAME>_SOURCE_DIR, <PROJECT-NAME>_BINARY_DIR, and <PROJECT-NAME>_IS_TOP_LEVEL if there is already a normal variable by that name when :command:project is called. The NEW behavior for this policy will always set normal variables for <PROJECT-NAME>_SOURCE_DIR, <PROJECT-NAME>_BINARY_DIR, and <PROJECT-NAME>_IS_TOP_LEVEL when :command:project is called.

.. |INTRODUCED_IN_CMAKE_VERSION| replace:: 3.31 .. |WARNS_OR_DOES_NOT_WARN| replace:: does not warn .. include:: include/STANDARD_ADVICE.rst

.. include:: include/DEPRECATED.rst