~neon/thoughts/2019/07/06/make

Atom Feed   Permalink

Writing about programs and programming.

My experience learning make

When I have been looking for a new language to learn, or gauging the usefulness of a language, I tend to appreciate build systems as part of the language. I think an important property of a tool is its simplicity of use, and for a long time I avoided C because it did not have a mvn, cargo, or npm. I thought the lack of an in-built build tool made C unnecessarily complicated to get started with. After reading bits and pieces of the K&R, making an almost whole game in C, and still not having touched makefiles, I have come to the conclusion that I was wrong. I have been happily writing C and building it with shell-scripts that build the program for each specific system. For example, I have a batch script for Windows that builds the program with cl.exe, providing the correct flags, one for Linux, and so on.

The reason I wrote the shell scripts instead of makefiles is because I already knew how shell scripts work, and learning to use cc and cl.exe was quite similar to learning to use the aforementioned build tools. If the compilers did not do something I needed from a build tool, I would just write that part in the script myself. In addition to this, I have heard a lot about makefiles not being super portable, and the existence of qmake and cmake seem to prove that idea. And in my own experience, when I have had to call make manually, it has stumbled on my system being misconfigured somehow, which makes it seem prone to breakage.

That said, I definitely feel like I should learn how to write a Makefile, if for no other reason than to make my negative opinion of them more valid. Or invalid, as the case may be ;)

Learning make

A few days ago, I got a copy of The Unix Programming Environment by Brian W. Kernighan and Rob Pike from the library. Why? The main reason was because I wanted to explore the Unix philosophy a bit further than what I had learned from hearing it repeatedly in tech articles and social media (not much). The other reason was because I imagined it would have a bit on make.

It does, sort-of. The eighth chapter is about writing a big program, and has three digressions on make. Based on that, I got the following impression of it: makefiles define dependencies between generated and manually edited files, and how those dependencies manifest (that is, how you get from the manually written files to the generated ones). The connection to C becomes obvious once you think about C programming in those terms: first you manually edit the C source code, then you generate object files out of that, and then you generate a final executable from those.

In this light, make seems like an obvious fit for C, but very general as well. I did not realize what the specific role of make was before, probably because other programming languages have built similar functionality into their build tools, but after this realization, it is obvious.

On one hand, I appreciate how cc and make split the job of making lots of source code into an executable (something something Unix philosophy), but on the other hand, I can not help but feel like it is pointlessly complicated for the end-user. Almost every program follows a similar build-pipeline, or could at least be refactored to fit, so why not combine the functionalities to a singular build tool? Why do I need to learn yet another syntax just to build my C? I imagine that is what a lot of people thought, since at least a few trillion different tools have been written to build a C program. I think. Ninja just sounds so out-there, that all the good names must have been taken already, which would infer many such tools. I do not actually know if ninja is a build tool. But I digress.

Conclusion

Make(1) is neat. I wrote a Makefile for this blog to test it out, and I enjoyed the experience after ironing out a few misunderstandings. It is a shame that make is the most universal tool to build C programs, I would much prefer a more cargo/go build-like experience, but it is not that bad either. If you are of a similar mindset to mine at the beginning of this post, just go ahead and use make. It is not evil. At the very least, it can not be as bad as picking one of the million other C build tools, because you do not get anywhere by making yet another standard, and you learn a new tool you can use for many other things as well. And make sure to be POSIX-compatible, just to be a good citizen :)

As a final note, The Unix Programming Environment has been a pretty fun read, if a bit obsolete. At least the C is, did you know functions looked like this in the 1970s?

main(argc, argv)
        char *argv[];
{
    // ...
}

Unimportant meta footnote you can skip

This is my first techblog, and I hope it was bearable to read. I think my English is a bit clumsy in long-form, so if you have got any writing tips, or just comments on this blog overall, be sure to shoot them at @neon@fedi.neon.moe on the Fediverse, or via email to jens@neon.moe.