An introduction to the build pipeline, and how we can orchestrate it manually

Before working with CMake, it's useful to understand the tools it orchestrates. This lesson guides you through setting up a C++ toolchain.

Building C++ Programs

Walking through the steps of the C++ compilation process, from source code to machine code.

The Compilation Pipeline

The linker's role in the build process, how it resolves symbols to combine object files, and how to troubleshoot common errors.

Object Files and the Linking Process

The difference between static and dynamic libraries, how to create them, and the trade-offs between them.

Static and Shared Libraries

The C++ Build Process

Recommended approaches for managing large projects and the libraries that they depend on

Learn how to structure your C++ projects for scalability and maintainability, from basic directory layouts to managing multiple modules.

Organizing a C++ Project

Learn to manage third-party libraries in C++, covering include/library paths, static vs. shared libraries, versioning, and platform differences.

Managing Libraries and Dependencies

An introduction to traditional build tools like Makefiles and IDE projects, highlighting the maintenance, scalability, and cross-platform challenges that result

Automated Build Systems and Their Limitations

Project Structure and Dependency Management

Setting up CMake and creating your first project

An introduction to CMake, the cross-platform, open-source meta-build system that solves the core challenges of C++ project management.

Why CMake?

A step-by-step guide to installing CMake. We'll explore command-line, GUI, and IDE workflows, and how to configure your compiler.

Setting Up a CMake Environment

Creating the bare minimum `CMakeLists.txt` file and build up to a project with an executable and a library, learning the fundamental commands along the way.

Writing a CMakeLists File

Learn the two-stage process of building a CMake project. This lesson covers configuring, generating, building, running, and troubleshooting common errors.

Building and Running CMake Projects

Learn how to organize large C++ projects in CMake using subdirectories and the `add_subdirectory()` command to create modular, maintainable builds.

CMake Project Structure and Subdirectories

Introducing CMake

Exploring CMake's programming features, caching mechanisms, and interactions with the file system

A primer on the fundamental building blocks of the CMake language: variables, string interpolation, and logging messages.

CMake Variables and Logging

Discover the CMake Cache, the mechanism for storing persistent user-configurable options, and learn how to create and manage cached variables.

The CMake Cache

Exploring CMake's command syntax and its list data type, including how to create, manipulate, and use lists in your projects.

CMake Commands, Arguments, and Lists

Transform your static build descriptions into dynamic scripts with CMake's control flow commands, if() and foreach().

CMake Conditionals and Loops

Exploring CMake's `file()` command, covering how to read, write, copy, and glob files, and how to manipulate paths.

Working with the File System

Learn to create reusable logic with CMake functions and macros, and how to organize them into modules for clean, scalable build systems.

Modularizing CMake Code

CMake Language and Fundamentals

Learn more about targets, and how their properties and links are the foundation of modern CMake

Learn to work with target properties - understanding their purpose, setting and updating them, and retrieving them when your build requires it

Target Properties

Learn about target types, and how the `PUBLIC`, `PRIVATE`, and `INTERFACE` keywords control how properties are shared.

Relationships Between Targets

Discover how CMake's `target_link_libraries()` command builds a dependency graph, and how it uses this graph to automatically manage transitive dependencies and link order.

Indirect Relationships and the Dependency Graph

Learn to use abstract target types like `INTERFACE`, `ALIAS`, and `IMPORTED` to model complex project needs, organize build properties, and integrate pre-compiled binaries.

Using `INTERFACE`, `ALIAS`, and `IMPORTED` Libraries

Adding support for user-configurable library types and an initial introduction to target installation.

Using Shared Libraries

Targets and Dependencies

Learn how to manage multiple build configurations within the same project, and how to create scripts that adapt to the environment

Learn how CMake manages different build configurations like Debug and Release, the difference between generator types, and how to apply settings conditionally using modern techniques.

Build Configurations (Debug, Release, etc.)

Learn the tools and patterns needed to write portable CMakeLists.txt files that work seamlessly across platforms and compilers

Cross-Platform Configurations

Learn to write architecture-aware CMake scripts for 32/64-bit systems and Apple's Universal Binaries (Intel/ARM).

Handling Different Architectures

Learn to build for different operating systems and architectures using CMake's cross-compilation support and toolchain files.

Cross-Compilation and Toolchain Files

Platforms and Build Configurations

Learn how to add external libraries to our build, and how to create our own packages for others to use

Learn to find and use pre-installed libraries with `find_package()`, understanding Module vs. Config mode and the power of imported targets

Finding Dependencies using `find_package()`

Learn how to make your libraries consumable by other projects using CMake by turning your build-tree into a distributable install-tree.

Creating a Consumable Package

Learn how to consume a CMake package you've installed, completing the producer-consumer cycle. We'll cover using `find_package()` and how to point CMake to your library's location

Using Installed Packages

Learn how to create self-contained, reproducible builds by fetching dependencies from source using `FetchContent()` and `ExternalProject_Add()`.

Fetching External Dependencies

Creating and Consuming Packages

Integrating the vcpkg and Conan package managers to handle external dependencies

Learn to manage C++ dependencies effortlessly with the vcpkg package manager and its seamless CMake integration using toolchain files and manifests.

Integrating CMake and vcpkg

Learn the day-to-day commands for managing dependencies with vcpkg and how to guarantee reproducible builds using baselines and version overrides

vcpkg Commands and Versioning

Combine vcpkg with CMake's cross-compilation capabilities. Learn to use triplets to target different architectures and chain-load toolchain files

Cross-Compiling with vcpkg

Discover Conan, the binary-first C++ package manager, and learn how to integrate it with CMake using profiles and lockfiles for fast, reproducible builds.

Using Conan with CMake

Learn to cross-compile C++ projects with Conan, using build and host profiles to manage dependencies for different platforms.

Cross-Compilation with Conan

Package Managers

Introducing presets, allowing us to simplify our workflow and share common configurations across our team

Learn the fundamentals of CMake Presets. This lesson introduces `CMakePresets.json` to simplify complex build commands.

CMake Presets

Learn to structure your CMake presets with inheritance and customize them for your local environment using `CMakeUserPresets.json`.

User Presets and Inheritance

Learn to make your CMake presets portable by using environment variables and conditional logic to adapt to different machine configurations.

Environment Variables and Conditional Presets

Learn how to extend the build process beyond simple compilation by integrating external tools and custom commands

Learn how to use generator expressions `$<...>` for build-time conditional logic.

Generator Expressions and Conditional Logic

Learn how to attach commands to specific points in a target's build lifecycle using `add_custom_command(TARGET)` for tasks like post-build file copying.

Integrating Tools with `add_custom_command()`

Learn to integrate code generators like Protobuf into your build process using `add_custom_command()`, creating automated file-level dependencies in CMake.

Generating Files with Protobuf and `add_custom_command()`

Custom Commands

An introduction to automating common workflow chores by creating custom targets

Learn to create standalone, non-code targets using add_custom_target() for utility tasks like code formatting and documentation generation.

Custom Targets and Build Utilities

Using the Clang-Format tool to automatically enforce a consistent coding style, and integrating it into our build using a custom CMake target

Using Clang-Format

An introduction to file sets and the `target_sources()` command, allowing us to manage our header files in a more controlled way

Using File Sets

A step-by-step guide to integrating Doxygen into your CMake build process for automated C++ documentation.

Generating Documentation with Doxygen

Custom Targets

Integrate automated tests into a CMake project using CTest, GoogleTest, and GoogleMock

Learn the fundamentals of automated testing in C++ with CTest. Create your first test suite, register tests with `add_test()`, and run them with the `ctest` command.

Automated Testing and CTest

Learn to refactor manual C++ tests into a professional test suite using the GoogleTest framework, managed by vcpkg and integrated with CTest.

Integrating GoogleTest with CMake

Learn to use a wide range of assertions, write data-driven parameterized tests, and isolate dependencies with Google Mock.

Assertions and Parameterized Tests

Learn how to isolate dependencies that our project uses, and then how to replace those dependencies at test time using Google Mock.

Dependency Injection and Mocking

Learn the standard pattern for testing application logic by refactoring it into a linkable library

Testing Executables

Move beyond individual tests to manage a full test suite. Learn to organize tests, run tests in parallel, filter by labels, and measure our code coverage

Managing a Test Suite

Automated Testing

Using static and dynamic analysis in CMake projects to automatically detect memory bugs, performance issues, and problematic code

Learn to find memory bugs at runtime by integrating AddressSanitizer (ASan) into a CMake project

Using AddressSanitizer (ASan)

Adding benchmarks to our build to measure the performance of our code, and track how it changes over time

Using Google Benchmark

Integrating Clang-Tidy to enforce good practices and find bugs before we even compile

Using Clang-Tidy

Automated Analysis

Automating the entire development lifecycle using Git for souce control, GitHub Actions for cloud builds, and CPack to create distributable packages and installers.

An introduction to Git, the version control system that underpins modern collaborative software development and automated build pipelines.

Source Control with Git

Learn how to automate your build and test process with Continuous Integration (CI) and a build server. This lesson provides a guide to creating a GitHub Actions workflow for a CMake project.

Build Servers and Continuous Integration

Learn to package your C++ projects using CMake's CPack. This lesson covers creating developer ZIP archives and professional Windows MSI installers with components.

Packaging with CPack

Learn to automate the packaging process by integrating CPack with a multi-platform GitHub Actions workflow

Packaging with GitHub Actions

Learn to automate the creation of a professional Windows installer by integrating CPack, the WiX Toolset, and a multi-platform GitHub Actions workflow.

Creating Installers with CPack and GitHub Actions

Learn to automate the release process using a GitHub Actions workflow that builds, packages, and publishes artifacts to a GitHub Release

Deployment with GitHub Releases

Continuous Integration and Packaging

If you have a basic grasp of C++ but find the build process intimidating, this course is for you. We assume you know the language, but not how to manage large projects.

Manage complex, cross-platform builds using industry-standard tools. Create scalable build systems that automate the entire development lifecycle.

This course is a comprehensive deep-dive into the entire C++ build ecosystem, centered around the power and flexibility of modern CMake. We leave no stone unturned.

Start with a foundational understanding of compilers, linkers, static vs. shared libraries, and object files.

The Full Build Pipeline

Learn every aspect of the CMake language, from variables and control flow to functions, modules, and generator expressions.

Complete CMake Language Mastery

Master the modern target-centric paradigm, including properties, usage requirements, and abstract targets.

Advanced Target Management

Explore every method for handling dependencies, from `find_package` and `FetchContent` to vcpkg and Conan, including versioning and cross-compilation.

In-Depth Dependency Management

Integrate a full suite of professional tools for testing (CTest, GoogleTest), analysis (ASan, Clang-Tidy), and packaging (CPack).

Total Workflow Automation

Build a fully automated deployment pipeline that takes your code from a Git push to a published GitHub Release with multi-platform installers.

End-to-End CI/CD and Deployment

What You'll Learn

Become a software engineer with C++.  Starting from the basics, we guide you step by step along the way

Intro to C++ Programming

If you're completely new to programming or want a thorough introduction, consider starting with our free introductory course:

New to Programming?

Managing C++ Projects Using CMake

In the last lesson, we integrated Conan into our project. We saw how its binary-first approach can speed up clean builds by avoiding the need to compile every dependency from source. We used a single, default profile to describe our native build environment.


But, how does this work when wer're cross-compiling?  What happens when the machine we're building **on** is different from the machine we're building **for**?  Conan has a different approach here than what we've seen previously. Rather than manually writing toolchain files, we rely more heavily on Conan's **profile** system.


## Recap: The Manual CMake Toolchain File


In our lesson on <InlineLessonPromo slug="cmake/cross-compilation-and-toolchain-files">cross-compilation</InlineLessonPromo>, we learned that the native CMake way to handle this is with a toolchain file. This file explicitly tells CMake about the target system and provides absolute paths to the cross-compilers.


A toolchain file for cross-compiling to Windows from a Unix-like host might look like this:


<CodeFile path="toolchains/manual-mingw.cmake">


```c++
#<cmake>
# 1. Set the target system
set(CMAKE_SYSTEM_NAME Windows)
set(CMAKE_SYSTEM_PROCESSOR x86_64)

# 2. Specify the cross-compilers
set(CMAKE_C_COMPILER x86_64-w64-mingw32-gcc)
set(CMAKE_C_FLAGS_INIT "-static -static-libgcc")

set(CMAKE_CXX_COMPILER x86_64-w64-mingw32-g++)
set(CMAKE_CXX_FLAGS_INIT
  "-static -static-libgcc -static-libstdc++")

set(CMAKE_EXE_LINKER_FLAGS_INIT
  "-static-libgcc -static-libstdc++")

# 3. Configure search for external dependencies
set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)
set(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)
set(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)
```


</CodeFile>


## Conan's Abstraction: The Profile as a Toolchain


Conan offers a higher-level solution. Instead of writing a script that tells CMake _**where**_ the tools are, you write a **Conan profile** that describes _**what**_ the target platform is.


What needs to go in any given profile may require some research, as it depends on the the platform you're targetting and the compiler you're using.  A fairly minimalist Conan profile for the same Windows target using `mingw32-gcc` might look something like this:


<CodeFile path="profiles/mingw-windows.profile" status="New">


```plain text
[settings]
os=Windows
arch=x86_64
build_type=Release
compiler=gcc

# Compiler-specific settings we want to use
compiler.version=15
compiler.cppstd=20
compiler.libcxx=libstdc++11
compiler.exception=seh
compiler.threads=posix

[conf]
tools.build:compiler_executables={"c": "x86_64-w64-mingw32-gcc", "cpp": "x86_64-w64-mingw32-g++"}

# Static linking to remove dependency on MinGW DLLs
tools.build:sharedlinkflags=["-static"]
tools.build:exelinkflags=["-static"]
```


</CodeFile>


When we use this profile, Conan takes on the responsibility of:

1. Finding a cross-compiler on our system that matches this description.
2. Finding or building Conan packages that match this exact configuration.
3. Generating a `conan_toolchain.cmake` file that contains all the low-level details that CMake needs.

## The Build/Host Context


As usual with cross-compilation, we need to consider two different environments simultenously - the environment where we're building the project, and the environment where the code is eventually going to be run.  In Conan terminology, this is the **build/host context**.

- The **`build`** **context** describes the machine you are building **on** (your machine).
- The **`host`** **context** describes the machine you are building **for** (the target machine).

Note that the naming convention here is different to what other tools use, and what we introduced previously.  Most other tools use the word "host" to refer to the machine that is performing the build.  Unfortunately, Conan's terminology uses it in the exact opposite way.  The "host" within Conan's context is the machine that our program will ultimately run on.


When you cross-compile, you need two profiles: one for the `build` context and one for the `host` context.


This is because some dependencies are tools that need to run during the build itself. The most obvious example is CMake itself, but we'll see some other examples soon, such as code generators and documentation generators.  These tools must be compiled for the `build` machine. Regular library dependencies, like `spdlog`, must be compiled for the `host` machine.


<Img hasTransparency invertible file="cmake-build-host-context.png" alt="Diagram showing the Conan cross compilation process" width="1400" height="1246" blurHash="LmMQ*JWBWBWBxuayayay~qj[fQj[" />


By using two separate profiles, Conan can resolve the entire dependency graph correctly by, for example, fetching macOS ARM libraries for our Apple build machine, but Windows binaries for the host (target) machine.


<Pw>


## Practical Example: Building for Windows with MinGW


Let's walk through the process of cross-compiling our `GreeterApp` from a macOS machine to a Windows executable again.  But, this time, we'll use Conan.


As a test application, we can use the same Windows code we used in previous examples.  The following program pops up a Windows `MessageBox`, and uses `spdlog` to create a log file next to the executable when we close the program:


<CodeFile path="app/src/main.cpp">


```c++
#include <windows.h>
#include <spdlog/spdlog.h>//<h>

int WINAPI WinMain(HINSTANCE, HINSTANCE, LPSTR, int) {
  auto logger{spdlog::basic_logger_mt(
    "file_logger", "log.txt"
  )};
  logger->info("Program started");

  MessageBox(
    nullptr,
    "I was cross-compiled from a Mac!",
    "Hello Windows",
    MB_OK
  );
  
  logger->info("Program shut down");
  
  // Flush logs to ensure they're written
  spdlog::shutdown();
  
  return 0;
}
```


</CodeFile>


We'll also use the same `conanfile.txt` from the previous lesson to handle the spdlog dependency:


<CodeFile path="conanfile.txt" status="New">


```plain text
[requires]
spdlog/1.15.3

[generators]
CMakeDeps
CMakeToolchain
```


</CodeFile>


### Step 1: Create the Host Profile


For Conan profiles that are intended to be shared alongside our project, we should store them within a directory in our project structure.  Let's call this directory `profiles` and, inside it, we'll create the `mingw-windows.profile` file we saw earlier.


<CodeFile path="profiles/mingw-windows.profile" status="New">


```plain text
[settings]
os=Windows
arch=x86_64
build_type=Release
compiler=gcc

# Compiler-specific settings we want to use
compiler.version=15
compiler.cppstd=20
compiler.libcxx=libstdc++11
compiler.exception=seh
compiler.threads=posix

[conf]
tools.build:compiler_executables={"c": "x86_64-w64-mingw32-gcc", "cpp": "x86_64-w64-mingw32-g++"}

# Static linking to remove dependency on MinGW DLLs
tools.build:sharedlinkflags=["-static"]
tools.build:exelinkflags=["-static"]
```


</CodeFile>


This profile assumes you have a MinGW-w64 cross-compiler installed (e.g., via Homebrew on macOS or `apt` on Linux) and that its executables are in your system `PATH`.


### Step 2: Run `conan install` with Two Profiles


Now, let's set up a clean build directory within our project root.  Let's first navigate there using the `cd` command:


```c++
//<ti>
cd /path/to/project-root
```


We can create a directory in our current location using the `mkdir` command, and then navigate into it using `cd` as usual.   We'll call our clean build directory `build-win` in this example.


```c++
//<ti>
mkdir build-win
```


```c++
//<ti>
cd build-win
```


From this location, we then run `conan install`. This time, we provide both a build and a host profile:


```c++
//<ti>
conan install .. \
  --profile:build=default \
  --profile:host=../profiles/mingw-windows.profile \
  --build=missing
```


```c++
//<o>
...
Install finished successfully
```


Let's break down this command:

- `conan install ..`: Reads the `conanfile.txt` from the parent directory.
- `-profile:build=default`: For any build tools, use our `default` native profile.
- `-profile:host=../profiles/mingw-windows.profile`: For our application's libraries, use the Windows target profile we just created.
- `-build=missing`: As before, this tells Conan to compile from source if it can't find a matching pre-compiled binary for our target.

Conan will now resolve our required libraries, downloading or building Windows versions of `spdlog` and its dependencies. It will then generate a `conan_toolchain.cmake` file in our current directory (`build-win`).


### Step 3: Configure and Build with CMake


The generated `conan_toolchain.cmake` file now contains all of our cross-compilation requirements, so the rest of the process looks the same as it did before.  We simply invoke the configure step with this `CMAKE_TOOLCHAIN_FILE` variable, and we provide the build type:


From inside the `build-win` directory, the command would look like this:


```c++
//<ti>
cmake .. \
  -DCMAKE_TOOLCHAIN_FILE=conan_toolchain.cmake \
  -DCMAKE_BUILD_TYPE=Release
```


Note that we must match the `CMAKE_BUILD_TYPE` to the `build_type` we specified in our Conan host profile.


Now, build the project:


```c++
//<ti>
cmake --build .
```


If you inspect the `build-win/app` directory, you'll find a `GreeterApp.exe` file. We can verify it's a Windows executable using the `file` command, or by running it in Windows or an emulator:


```c++
//<ti>
file app/GreeterApp.exe
```


```c++
//<o>
app/GreeterApp.exe: PE32+ executable (console) x86-64, for MS Windows
```


<Img hasTransparency file="cmake-cross-compile-output.png" alt="Diagram showing our cross-compiled program running natively and in an emulator" width="1200" height="496" blurHash="L.LXVzofofj[~qoffkay9FfRayay" />


After running the application, we should also see a log file created with help from our Conan-managed spdlog dependency:


<CodeFile path="logs.txt">


```c++
[2025-08-22 10:57:21.499] [file_logger] [info] Program started
[2025-08-22 10:57:26.165] [file_logger] [info] Program shut down
```


</CodeFile>


## Summary


Conan's profile-based approach provides an alternative solution for C++ cross-compilation, abstracting away the low-level details of toolchain management.

- **Profiles as Abstractions**: Instead of manual toolchain files, Conan uses profiles to describe the target platform. Conan finds the tools and binaries that match the description.
- **Build vs. Host Context**: Cross-compilation requires two profiles: one for the `build` machine (where tools run) and one for the `host` machine (where the final application runs).
- **Seamless CMake Integration**: The `conan install` command, when given both profiles, generates a single `conan_toolchain.cmake` file that configures your entire cross-build, requiring no changes to your `CMakeLists.txt`.
- **Portable Workflow**: This approach keeps your project's build logic clean and portable, while the platform-specific details are neatly encapsulated in shareable profile files.

<Preview>


### Simplifying Workflows with CMake Presets


By this point, you've probably noticed an annoying part of the workflow. When our project configuration needs several arguments, our command-line invocations can get quite long. For our cross-build, we had to enter:


```c++
//<ti>
conan install .. \
  --profile:build=default \
  --profile:host=../profiles/mingw-windows.profile \
  --build=missing
```


Followed by:


```c++
//<ti>
cmake .. \
  -DCMAKE_TOOLCHAIN_FILE=conan_toolchain.cmake \
  -DCMAKE_BUILD_TYPE=Release
```


Remembering, typing, and sharing commands like this is tedious and error-prone. How can we simplify things?


In the next chapter, we will introduce **CMake Presets**. We'll learn how to use a `CMakePresets.json` to define and name these complex configurations, allowing any developer to select a common set of configurations with a simple command like `cmake --preset=windows-release`.


</Preview>


</Pw>

Package Managers Integration (Conan)

How to cross-compile your applications using Conan: host and build contexts

Profiles

CMake Toolchains

CMake and Conan: past, present and future - Diego Rodriguez-Losada

CMake + Conan: 3 Years Later - Mateusz Pusz

Master C++ cross-compilation with this Conan and CMake tutorial. Learn to use build and host profiles to manage dependencies and toolchains for targets like Windows, Linux, or embedded systems, all from a single build machine.

CMake & Conan Cross-Compilation: Building for Any Platform

Conan's Abstraction: The Profile as a Toolchain

Practical Example: Building for Windows with MinGW

Step 2: Run `conan install` with Two Profiles

Cross-Compilation with Conan

Understanding the Basics

Practical Applications

Common Mistakes

Next Steps

Additional Resources

Assessment Preparation

Managing C++ Projects Using CMake