RAPIDS-CMake Basics

Installation

The rapids-cmake module is designed to be acquired at configure time in your project. Download the RAPIDS.cmake script, which handles fetching the rest of the module’s content via CMake’s FetchContent.

cmake_minimum_required(...)

if(NOT EXISTS ${CMAKE_CURRENT_BINARY_DIR}/<PROJ>_RAPIDS.cmake)
  file(DOWNLOAD https://raw.githubusercontent.com/rapidsai/rapids-cmake/branch-24.10/RAPIDS.cmake
    ${CMAKE_CURRENT_BINARY_DIR}/<PROJ>_RAPIDS.cmake)
endif()
include(${CMAKE_CURRENT_BINARY_DIR}/<PROJ>_RAPIDS.cmake)
include(rapids-cmake)
include(rapids-cpm)
include(rapids-cuda)
include(rapids-export)
include(rapids-find)

project(...)

Usage

rapids-cmake is designed for projects to use only the subset of features that they need. To enable this rapids-cmake comprises the following primary components:

• cmake

• cpm

• cython

• cuda

• export

• find

• testing

There are two ways projects can use rapids-cmake functions.

1. Call include(rapids-<component>), which imports commonly used functions for the component.

2. Load each function independently via include(${rapids-cmake-dir}/<component>/<function_name>.cmake).

Overriding RAPIDS.cmake

At times projects or developers will need to verify rapids-cmake branches. To do this you can set variables that control which repository RAPIDS.cmake downloads, which should be done like this:

# To override the version that is pulled:
set(rapids-cmake-version "<version>")

# To override the GitHub repository:
set(rapids-cmake-repo "<my_fork>")

# To use an exact Git SHA:
set(rapids-cmake-sha "<my_git_sha>")

# To use a Git tag:
set(rapids-cmake-tag "<my_git_tag>")

# To override the repository branch:
set(rapids-cmake-branch "<my_feature_branch>")

# Or to override the entire repository URL (e.g. to use a GitLab repo):
set(rapids-cmake-url "https://gitlab.com/<my_user>/<my_fork>/-/archive/<my_branch>/<my_fork>-<my_branch>.zip")

# To override the usage of fetching the repository without git info
# This only works when specifying
#
# set(rapids-cmake-fetch-via-git "ON")
# set(rapids-cmake-branch "branch-<cal_ver>")
#
# or
# set(rapids-cmake-fetch-via-git "ON")
# set(rapids-cmake-url "https://gitlab.com/<my_user>/<private_fork>/")
# set(rapids-cmake-sha "ABC123")
#
set(rapids-cmake-fetch-via-git "ON")

file(DOWNLOAD https://raw.githubusercontent.com/rapidsai/rapids-cmake/branch-22.10/RAPIDS.cmake
    ${CMAKE_CURRENT_BINARY_DIR}/RAPIDS.cmake)
include(${CMAKE_CURRENT_BINARY_DIR}/RAPIDS.cmake)

A few notes:

• An explicitly defined rapids-cmake-url will always be used

• rapids-cmake-sha takes precedence over rapids-cmake-tag

• rapids-cmake-tag takes precedence over rapids-cmake-branch

• It is advised to always set rapids-cmake-version to the version expected by the repo your modifications will pull

An incorrect approach that people try is to modify the file(DOWNLOAD) line to point to the custom rapids-cmake branch. That doesn’t work as the downloaded RAPIDS.cmake contains which version of the rapids-cmake repository to clone.