Distributing C++ projects as executable binaries with CMake

05 Oct 2023

One of the crucial aspects of software development is distributing your code as executable binaries that users can easily run on their machines. In the case of C++, CMake can be a valuable tool to help you create a smooth distribution process for your projects. In this blog post, we will explore how to use CMake to distribute your C++ projects as executable binaries.

Why use CMake for building and distributing C++ projects?

CMake is a powerful and widely-used build system generator that allows you to specify your project’s build configuration in a platform-independent way. It provides a simple and unified syntax for defining build targets, dependencies, and other build-related settings.

Using CMake for building and distributing C++ projects offers several benefits:

Cross-platform compatibility: CMake generates build scripts or project files specific to your platform (e.g., Linux, macOS, Windows), making it easier to distribute your project to users across different operating systems.
Dependency management: CMake allows you to manage third-party libraries and dependencies seamlessly. It provides mechanisms for locating, downloading, and integrating external libraries into your build process.
Incremental build support: CMake efficiently handles incremental builds, keeping track of dependencies and only rebuilding what is necessary. This means faster build times, especially for larger projects.

Now, let’s take a look at an example project and see how we can use CMake to distribute it as an executable binary.

Setting up the CMake project

Assuming you have a C++ project with the following structure:

project/
├─ src/
│  ├─ main.cpp
│  ├─ another_file.cpp
│  └─ ...
└─ CMakeLists.txt

Start by creating a CMakeLists.txt file in the root directory of your project.
Begin by specifying the minimum required CMake version at the beginning of the file:
```
cmake_minimum_required(VERSION 3.12)
```
Next, give your project a name using the project() command. This will also set a variable called PROJECT_NAME:
```
project(MyProject)
```

Define the executable target and its sources:

add_executable(${PROJECT_NAME} src/main.cpp src/another_file.cpp)

If your project depends on external libraries, use the find_package() command to locate and include them:
```
find_package(OpenGL REQUIRED)
target_link_libraries(${PROJECT_NAME} PRIVATE ${OPENGL_LIBRARIES})
```
Finally, specify any additional compilation options or flags that your project requires:
```
target_compile_options(${PROJECT_NAME} PRIVATE -Wall -Wextra -pedantic)
```

Building the project

To build the project, follow these steps:

Create a build directory in the root of your project:

project/
├─ src/
├─ build/
└─ CMakeLists.txt

Navigate to the build directory in your terminal or command prompt.
Run the following command to generate the build files:
```
cmake ..
```
Once the build files are generated, you can use your platform-specific build system (e.g., Make, Visual Studio, Xcode) to build the project. For example, on Linux, you can use the make command:
```
make
```
This will create the executable binary in the build directory.

Distributing the executable

To distribute the executable binary to users, you can simply provide them with the compiled binary file. Make sure to include any necessary runtime dependencies alongside the executable if required.

You can also consider packaging your project into a platform-specific installer or package format (e.g., .deb, .rpm, .dmg, .msi) for easier installation and distribution.

Conclusion

Using CMake for building and distributing C++ projects provides a platform-independent solution that simplifies the process of generating executable binaries. It gives you control over project configuration, versatile dependency management, and efficient incremental builds. By following the steps outlined in this blog post, you can easily distribute your C++ projects to users across different platforms.

#programming #C++