.. _infra-cmake-preset-reference:

Preset reference
================

CCCL ships its CMake configurations as presets in ``CMakePresets.json``, using CMake's
`preset format <https://cmake.org/cmake/help/latest/manual/cmake-presets.7.html>`_. The file
defines 40+ presets covering each library, multiple C++ standards, special build
modes, and benchmarking.

Preset structure
----------------

Each preset belongs to one of three sections:

- ``configurePresets`` set the configuration: enabled libraries, build type, CUDA
  architectures, C++ standard, and per-library options. Every configure preset
  inherits from the hidden ``base`` preset, which selects the Ninja generator,
  Release mode, ``all-major-cccl`` architectures, and disables all libraries by
  default. A named preset enables the libraries and options it needs.
- ``buildPresets`` reference a configure preset by name. Some pin an explicit
  target list; most build everything the configuration enables.
- ``testPresets`` reference a configure preset and add CTest filters. Filters
  select a subset of tests by name regex. CUB launcher-mode presets and Thrust
  GPU/CPU splits are examples of this pattern.

A configure preset, its build preset, and its test preset share a name. Run all
three with the same ``<name>``.

Listing available presets
-------------------------

``cmake --list-presets`` prints all configure presets::

   cmake --list-presets

List build and test presets separately::

   cmake --list-presets=build
   cmake --build --list-presets
   ctest --list-presets

Using a preset
--------------

Configure, then build with the matching preset name::

   cmake --preset cub-cpp17
   cmake --build --preset cub-cpp17

Run the test preset of the same name with ``ctest``::

   ctest --preset cub-cpp17

Build output lands under ``build/<infix>/<presetName>/``, where the infix comes from
the ``CCCL_BUILD_INFIX`` environment variable used for devcontainer isolation.
Distinct presets use distinct build directories and do not collide.