CMake version recommendations and install

CMake ≥ 3.17 is strongly recommended for users in general for more robust and easy syntax. For project developers, we recommend CMake >= 3.19 as the new features make debugging CMake and setting up CI considerably easier. For features added in 3.19 that we use, we suggest CMake upgrade via status messages to older CMake users.

Downloading the latest release of CMake is usually easy. For Linux and Mac, admin/sudo is NOT required.

There is an unoffical PyPi CMake package:

python -m pip install cmake

For platforms where CMake binaries aren’t easily available, use build_cmake.cmake.

Key features added

The priority of these features is subjective–we write from the scientific computing perspective.

CMake 3.20 adds support for Intel NextGen LLVM compiler and NVIDIA HPC compiler. ExternalProject_Add() learned CONFIGURE_HANDLED_BY_BUILD which avoids CMake commanding a reconfigure on each build. try_compiler(WORKING_DIRECTORY) was added. CMakePresets.json now covers configure, build and test, allowing many parameters to be declared with inheritance in JSON. The presets are quite handy for CI, as well as user configurations.

CMake 3.19 added support for ISPC language. string(JSON GET|SET) parsing is very useful to avoid hard-coding parameters. FindPython/find_package accepts version ranges. Intel oneAPI works with CMake >= 3.19.3. Emits deprecation warning for cmake_minimum_required VERSION less than 2.8.12. CMakePresets.json enables configure declarations in JSON, extended to build and test in CMake 3.20

CMake 3.18 adds CMake Profiler cmake -B build --profiling-output=perf.json --profiling-format=google-trace

CMake 3.17 adds Ninja Multi-Config generator. cmake --debug-find shows what find_package() is doing. Eliminates Windows “sh.exe is on PATH” error. Recognizes that Ninja 1.10 correctly works with Fortran.

CMake 3.16 adds precompiled headers, unity builds, many advanced project features.

CMake 3.15 addes CMAKE_GENERATOR environment variable that works like global -G option. Enhances Python interpreter finding. Adds cmake --install command instead of “cmake –build build –target install”.

CMake 3.14 is where we added check_fortran_source_runs(). FetchContent was enhanced with simpler syntax. The transitive link resolution was considerably enhanced in CMake 3.14. Projects just work in CMake >= 3.14 that fail at link-time with CMake < 3.14.

We don’t recommend use of the older CMake versions below as they take significantly more effort to support.

CMake 3.13 adds ctest --progress and better Matlab compiler support. Lots of new linking options are added, fixes to Fortran submodule bugs. The very convenient cmake -B build incantation, target_sources() with absolute path are also added. It’s significantly more difficult to use CMake older than 3.13 with medium to large projects.

CMake 3.12 adds transitive library specification (out of same directory) and full Fortran Submodule support. get_property(_test_names DIRECTORY . TESTS) retrieves test names in current directory.

CMake 3.11 allows specify targets initially w/o sources. FetchContent is added, allowing fast hierarchies of CMake and non-CMake projects.

The versions of CMake below have been deprecated as of CMake 3.19.

CMake 3.10 added Fortran Flang (LLVM) compiler and extensive MPI features.

CMake 3.9 added further C# and Cuda support, that was originally added in CMake 3.8.

CMake 3.8 added initial Cuda support

CMake 3.7 added comparing ≤ ≥ and version comparisons. Initial Fortran submodule support was added.

CMake 3.6 gave better OpenBLAS support.

CMake 3.5 enhanced FindBoost target with auto Boost prereqs.

CMake 3.4 added if(TEST) to see if a test name exists.

CMake 3.3 added list operations such as IN_LIST.