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Comment by Joker_vD | Hacker News Reader

Honestly, I never quite understood the point of generating the makefiles: if you have a tool that knows where the inputs are, where the outputs should be, and tracks the dependencies changing from build to build (something that "make" famously struggles to do), then surely that tool can also run whatever compilers/linkers/etc. are needed?

I guess you can commit the generated makefile into your repo so that those who want to build your project from sources don't need your custom build tool installed, only make...

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Historically, Makefiles generation is merely a cache of platform introspection on systems that were orders of magnitudes slower than what we have now. I suspect that any other approach based on Makefile only would have implied higher memory consumption and/or implied slow rotating disk I/O.

Actually on my 64-thread Threadripper that cache is more important than ever as the make step parallelizes nicely but the configure step usually is 100% serialized.

Take a look at FreeBSD. Here’s what a typical Makefile looks like:

# $FreeBSD$

PACKAGE=runtime PROG= setfacl SRCS= file.c mask.c merge.c remove.c setfacl.c util.c

.include <bsd.prog.mk>

So, yeah, at least for code in C you can have something maintainable in make(1), it’s just you need to structure your project in a sensible way.

Does it support incremental builds? How does it detect include dependencies? Is it portable?

1. Sure (if you didn’t need incremental builds, why bother with make at all? Just use sh.)

2. It doesn’t, it’s programmers job to make an effort to append a file name to a single line in a single file.

3. It’s portable in the same way autotools are portable, which means you can make it work with relative ease.

Most builds are divided into two phases. The first phase "do we have libfoo installed, where is doxygen, are tests enabled" is run infrequently. The second phase "recompile everything that needs to be recompiled" is run over and over again. The second phase is more or less a solved problem now given that Ninja exists. The first phase is where a lot of people have different ideas and tastes, so we get cmake, meson, autotools, etc.

You can certainly do everything in one system. In practice this seems to lead to a build process that is much slower than it needs to be, see for instance Scons.

Or see cargo, go build, dune, etc.

These are all tools that specialise in building only a particular kind of project. They are useful, but aren't really in the same category of general build tools like Ninja and Make.

There are many nuances. How to control parallelism, how to present output, checking freshness, etc. It is much easier to generate Ninja files and let Ninja do all the boring work.

What are the dependencies of Ninja? (I seem to remember it being a Python tool?)

On macOS at least, Ninja is just a 362 kByte native executable without dependencies except dynamically linking with the system-provided libc++ and libSystem DLLs (you're probably thinking of Meson?)

Ah, that might be it! Thanks!

Do you want to hand parallelization in your little custom tool?

Well, cargo has it. So does go build. And dune. And MSBuild. And... basically, every language-specific (and non-specific) build tool out there handles it, so yes? Sure, it's not exactly according to the UNIX philosophy but judging by other comments in this thread, if one wants a low-level parallelizeable build tool, they should use Ninja instead of Make anyhow.

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