Linux                                      | macOS                                      | Windows
------------------------------------------ | ------------------------------------------ | -------
[![Status][linux_cpp_svg]][linux_cpp_link] | [![Status][macos_cpp_svg]][macos_cpp_link] | [![Status][windows_cpp_svg]][windows_cpp_link]

[linux_cpp_svg]: https://github.com/google/or-tools/actions/workflows/cmake_linux_cpp.yml/badge.svg?branch=main
[linux_cpp_link]: https://github.com/google/or-tools/actions/workflows/cmake_linux_cpp.yml
[macos_cpp_svg]: https://github.com/google/or-tools/actions/workflows/cmake_macos_cpp.yml/badge.svg?branch=main
[macos_cpp_link]: https://github.com/google/or-tools/actions/workflows/cmake_macos_cpp.yml
[windows_cpp_svg]: https://github.com/google/or-tools/actions/workflows/cmake_windows_cpp.yml/badge.svg?branch=main
[windows_cpp_link]: https://github.com/google/or-tools/actions/workflows/cmake_windows_cpp.yml

# Introduction

For building OR-Tools as a CMake standalone project, you can read the following
instructions.

This project should run on GNU/Linux, MacOS and Windows.

## C++ Project Build

1.  Get the source code and change to it.

    ```sh
    git clone https://github.com/google/or-tools.git
    cd or-tools
    ```

2.  Run CMake to configure the build tree.

    ```sh
    cmake -S. -Bbuild -DCMAKE_BUILD_TYPE=Release -DBUILD_DEPS=ON
    ```
    note: To get the list of available generators (e.g. Visual Studio), use `-G`

3.  Afterwards, generated files can be used to compile the project.

    ```sh
    cmake --build build --config Release -v
    ```

4.  Test the build software (optional).

    ```sh
    cmake --build build --target test
    ```

5.  Install the built files (optional).

    ```sh
    cmake --build build --target install
    ```

## Testing

To list tests:

```sh
cd build
ctest -N
```

To only run C++ tests:

```sh
cd build
ctest -R "cxx_.*"
```

## Technical Notes

### Managing RPATH

Since we want to use the
[CMAKE_BINARY_DIR](https://cmake.org/cmake/help/latest/variable/CMAKE_BINARY_DIR.html)
to generate the wrapper package (e.g. python wheel package) as well as be able
to test from the build directory. \
We need to enable:

```cmake
set(CMAKE_BUILD_WITH_INSTALL_RPATH TRUE)
```
And have a finely tailored rpath for each library.