Make It Simple - An Empirical Analysis of GNU Make Feature Use in Open Source Projects

Make is one of the oldest build technologies and is still widely used today, whether by manually writing Make files, or by generating them using tools like Auto tools and CMake. Despite its conceptual simplicity, modern Make implementations such as GNU Make have become very complex languages, featuring functions, macros, lazy variable assignments and (in GNU Make 4.0) the Guile embedded scripting language. Since we are interested in understanding how widespread such complex language features are, this paper studies the use of Make features in almost 20,000 Make files, comprised of over 8.4 million lines, from more than 350 different open source projects. We look at the popularity of features and the difference between hand-written Make files and those generated using various tools. We find that generated Make files use only a core set of features and that more advanced features (such as function calls) are used very little, and almost exclusively in hand-written Make files.