Make

Make is a classic build automation tool that has been a staple on Unix-like systems for decades. It uses files, typically named Makefile, to specify dependencies between files and the rules for building them. It automatically determines which pieces of a program need to be recompiled and issues commands to recompile them.

GNU Make is a build automation tool that uses a special configuration file called a

Makefile to control the generation of executables and other non-source files from a program’s source files. It automatically determines which parts of a program need to be recompiled based on file modification times and the dependencies specified in the Makefile. The tool then runs the necessary shell commands to update any outdated files. 

The Make language 

The language used in Makefiles is a rule-based syntax that is not a general-purpose programming language. It is designed to define and manage dependencies and to execute shell commands. 

Key components of the language include: 

  • Rules: These consist of a target, its prerequisites, and a recipe. The target is the file to be created, the prerequisites are the files that the target depends on, and the recipe is a series of shell commands used to create the target.
  • Variables: Used to store strings that can be reused throughout the Makefile, such as compiler flags or lists of source files.
  • Functions: Built-in functions for text and filename manipulation, as well as conditional logic, are provided.
  • Implicit Rules: Make has a set of built-in rules for common tasks like compiling C and C++ files, which can simplify the Makefile. 

GNU Make vs. CMake 

While both are used for managing the build process, they operate at different levels of abstraction. The core difference is that CMake is a build-system generator, while GNU Make is the build system itself.

Aspect GNU Make CMake
Philosophy A lower-level, dependency-based tool that executes shell commands. It directly compiles your code based on explicit rules you write. A higher-level, cross-platform build generator. It produces native build files (like Makefiles, Visual Studio projects, or Ninja build files) that are then used by the actual build system.
Language Uses a rule-based, imperative language focused on explicit instructions. It requires manual handling of platform-specific details and dependency tracking. Uses a higher-level scripting language (CMakeLists.txt) to describe the project’s structure, targets, and dependencies. It is more abstract and feature-focused.
Platform Support Makefiles are inherently platform-specific. Writing a portable Makefile that works across different operating systems (e.g., Linux and Windows) and compilers is challenging and complex. Is designed for cross-platform development. A single CMakeLists.txt can generate native build files for various platforms and IDEs, including Unix Makefiles, Visual Studio, and Xcode.
Project Management Better suited for smaller, simpler projects with fewer files and dependencies. For large, complex projects, Makefiles can become difficult to maintain manually. Manages large, complex, multi-directory projects more easily. It has built-in support for finding external libraries, handling dependencies, and managing out-of-source builds.
Workflow The workflow is a single step: you run the make command, and it builds the project. The workflow is two-step: first, you run cmake to configure the project and generate the build files; second, you run the native build tool (like make) to compile the code.
Dependency Resolution Dependencies must be manually specified. While advanced patterns exist, correctly handling header file dependencies is often non-trivial. Automates dependency handling, especially for include files, which significantly reduces the effort required to get correct incremental builds.