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Comment by Ashymad | Hacker News Reader

But rust absolutely does not have any C/C++ compatibilty besides arguably very good FFI. And that's where zig shines. They have a c/c++ compiler built into the zig compiler via zig cc, that's even easier to use than clang or GCC due to having the benefits of a buildscript and baked in libcs for different architectures, making crosscompilation a breeze.

In zig you _can_ actually start with a c codebase and rewrite it file by file in zig and you _can_ include c headers in your zig files verbatim. Both of these are not possible in rust.

This milestone is only gonna remove the c++ (and objective c/c++) compiler for now from zig cc. So while you could argue this will ostracize people rewriting their c++ codebases in zig, I don't imagine there's actually many people like that. EDIT: I just looked at the discussion and there's actually a lot of people that use the c++ capapbilities.

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> In zig you _can_ actually start with a c codebase and rewrite it file by file in zig and you _can_ include c headers in your zig files verbatim. Both of these are not possible in rust.

well, you can: i have done this, with Rust. but yes, it’s more the type of thing that well-resourced companies do rather than solo devs, because even with Bindgen and the like Rust really wants the atomic codegen unit to be the “library”, not C’s notion of a “compilation unit”. still, C FFI compatibility is exactly why porting from C to rust incrementally is feasible while C to, say Java, is probably a bigger leap.

You still need a separate compiler toolchain next to Rust in order to compile the C, C++ and ObjC dependencies which is a massive build system headache (especially across UNIX-oids and Windows).

In Zig that all "just works" with the standard Zig install.

Show me a C/C++ project that doesn't need a build system.

My stuff for instance:

https://github.com/floooh/sokol

...inspired by:

https://github.com/nothings/stb

(here's how the sokol headers are integrated into a Zig project, note that there is only a build.zig which builds everything: https://github.com/floooh/kc85.zig)

But it's not so much about build systems, but requiring a separate compiler toolchain to build any C++ or ObjC dependencies (Rust needs this, Zig currently does not - unless that controversial proposal is implemented).

(also even complex C++ libraries can be wrapped in a build.zig, so you don't require a separate build system like cmake for the C++ dependencies)

I still don't see why this is a problem. Single-header dependencies are cute but blow up compile times, and most of the world needs CMake/Meson/Autotools anyways so there's not an added cost to using it for your own projects.

Similarly I don't really understand why you want one toolchain for a multi-language project. It's not that useful or convenient since it's going to need to be orchestrated with a buildsystem somehow.

Like with Rust, you probably only have a build.rs file. It invokes a separate (possibly multiple) toolchains. Or with CMake. A simple project has a single CMakeLists.txt that can invoke any number of toolchains. I don't see why zig can't do that with a build.zig file, or why it matters.

Did you try the stuff you are proposing? This is all a royal pita in real world projects which the Zig toolchain solved wonderfully.

(also it's a myth that STB style libs increase compile time, that's only true for typical C++ header-only libs with inline methods and template code)

> But rust absolutely does not have any C/C++ compatibilty besides [..]

> In zig you _can_ actually start with a c codebase and rewrite it file by file in zig and you _can_ include c headers in your zig files verbatim. Both of these are not possible in rust.

You can. Either via FFI and bindgen-ing headers, or by using c2rust. The latter is not just a toy ambitious project, but actually a very impressive piece of engineering and does produce a result where you can transpile a project or file and start rewriting file-by-file or function-by-function.

c2rust is definitely cool, but it also supports transpiling to a single architecture, which often misses a lot of architecture dependent code and specialisations in real world c code. Especially because it has to do macro expansion and you only get the expanded code.

It also doesn't supportal a good amount of more complicated c features.

It's a help for sure, but the few times I tried I ended up just doing the rewrite by hand instead to actually cover all the cases.

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