====== The DUNE cmake setup ======
DUNE uses [[https://cmake.org/|cmake]] to control its build process (creates makefiles).

===== Debug build =====
By default, running the cmake on DUNE disables debugging. To enable this, add the '''-DDEBUG=TRUE''' flag when invoking cmake.

===== Changing Toolchain =====
By default, the toolchain in '''dune/cmake/Toolchain.cmake''' is used. An example of setting up an alternative toolchain is available at [[ubuntu_cross_compiler|Ubuntu cross compiling with libraries]].

===== Adding External Libraries =====
External libraries is configured through the files at '''dune/cmake/Libraries'''. These check if the respective library is available, and then adds the needed include directories with headers and linked libraries. In addition, they each set cmake flags like '''DUNE_USING_JPEG''' or '''DUNE_SYS_HAS_JPEG'''. These flags can then be used cmakefiles of individual tasks to ensure the task is only built if the required library was successfully included.

===== Building with only a Subset of Tasks =====
To reduce compile time and binary size, an option is to only build a selection of the tasks included with DUNE. This can be done by setting the ''TASK_FILE'' variable when invoking cmake, and pointing it towards a file containing calls to either ''dune_add_task'' or ''dune_add_tasks''. Example call:
  cmake -DTASK_FILE=../dune/user/taskFile.cmake ../dune


Example of content to put in the ''TASK_FILE'':
  dune_add_tasks(${PROJECT_SOURCE_DIR}/user/src)
  dune_add_task(${PROJECT_SOURCE_DIR}/src Transports/Announce/Task.cmake)