mgcooper / fortran-stdlib-cmake-example

Using stdlib in your project

The Fortran standard library (stdlib) is developed by the Fortran-lang community. This projects shows how to integrate stdlib in your CMake project.

For a quick start you can include stdlib as git submodule in your projects by

git submodule https://github.com/fortran-lang/stdlib subprojects/stdlib

Users must initialize the submodule themselves when building your project, unless you let CMake perform this operation on demand.

Alternatively, you can use the FetchContent module of CMake to retrieve the git repository while configuring the project. A CMake snippet supporting both approaches is given here

# Include the stdlib project
if(EXISTS ${CMAKE_CURRENT_SOURCE_DIR}/stdlib/CMakeLists.txt)
  add_subdirectory("stdlib")
else()
  set("stdlib-url" "https://github.com/fortran-lang/stdlib")
  message(STATUS "Retrieving stdlib from ${stdlib-url}")
  include(FetchContent)
  FetchContent_Declare(
    "stdlib"
    GIT_REPOSITORY "${stdlib-url}"
    GIT_TAG "HEAD"
  )
  FetchContent_MakeAvailable("stdlib")
endif()

A more elaborated CMake module for making stdlib available can be found here. This module makes sure the fortran_stdlib::fortran_stdlib target is always generated regardless of how the stdlib is included in the project.

You can configure stdlib by setting the appropriate options before including the subproject. Important options are

• BUILD_SHARED_LIBS should be set to off if you want to link statically against stdlib
• CMAKE_MAXIMUM_RANK determines the maximum rank of arrays supported in stdlib, the default value is 15. To save compile time you can reduce this value to the maximum rank needed in your application.

This project offers a ready to use integration of stdlib for CMake, including an exported library and a binary application. Additionally, some boilerplate text in the README is available below as well as a testing setup with GitHub actions for GCC. The general CMake style should allow you to reuse most of the CMake build files without modification, just change the project name, add your source files and you are ready to go.

You can just use this template to create new project. Remove this introduction from the README afterwards and fill in your project details.

For more information on stdlib visit its documentation.

Installation

To build this project you need

• A Fortran compiler supporting Fortran 2008 or later (gfortran or ifort)
• CMake version 3.14 or later
• The fypp preprocessor
• A build backend, ninja (version 1.10 or newer) or make

Configure the build with (set the CMAKE_INSTALL_PREFIX to your preferred install location)

cmake -B _build -G Ninja -DCMAKE_INSTALL_PREFIX=$HOME/.local

To build the project run

cmake --build _build

Finally, you can install the project with

cmake --install _build

License

This project is free software: you can redistribute it and/or modify it under the terms of the MIT license.