Project options#
It is important to avoid name-clashing with the options, therefore all the options defined by the project must be appropriately namespaced. Here we will look on some good default options to implement.
<PROJECT>_TESTS#
This option enables the build of the test-suite from the main project.
It is important to set the default value to PROJECT_IS_TOP_LEVEL: when the
project is imported through FetchContent, it will not automatically populate
the importing project’s tests with the dependent’s tests.
<PROJECT>_INSTALL#
This option enables the installation of the project when calling cmake --install.
It is important to set the default value to PROJECT_IS_TOP_LEVEL: when the
project is imported through FetchContent, it will not also install the
dependent project and accidentally overwrite the system installation. This works
well in combination with <PROJECT>_SHARED_LIBS.
Dependency flags#
For most dependencies, it is preferred to make the dependencies optional and use
the built-in CMake variables CMAKE_REQUIRE_FIND_PACKAGE_<PackageName> and
CMAKE_DISABLE_FIND_PACKAGE_<PackageName> to control how these dependencies
should be treated.
Exception to the rule are dependencies that drastically change the project’s
behavior, e.g. MPI or OpenMP, and dependencies that have various variants, e.g.
FFTW or MKL. A common pattern is to use the <PROJECT>_<Dependency> as the
option name.
Other feature options#
Other options are up to the discretion of the project. Here it is useful to
mention add_feature_info as a way to display a useful summary for the user
through FeatureSummary.