CMAKE_XCODE_GENERATE_TOP_LEVEL_PROJECT_ONLY

.. versionadded:: 3.11

If enabled, the :generator:Xcode generator will generate only a single Xcode project file for the topmost :command:project() command instead of generating one for every project() command.

This could be useful to speed up the CMake generation step for large projects and to work-around a bug in the ZERO_CHECK logic.