Providing statically linked toolchains

[cbarrete]

I've just come across https://toolchains.bootlin.com/ while trying to source a static toolchain to generate static binaries, thanks a lot for making it available!

My goal is to build an easy to use hermetic build environment, which requires sourcing tools that have as few as possible to no dependencies on the system, including libc, so that the build can run on older systems, or weirder ones like NixOS.

One way would be to provide a toolchain that contains tools built with musl, as well as providing musl as the sysroot libc. Is this something that would be in scope for this project?

Thanks!

[tpetazzoni]

Providing musl as the sysroot libc (i.e as the libc for the target) is already done by this project, as we provide toolchains targeting glibc, uclibc and musl.

However, statically linking the toolchain binaries on the host with musl isn't currently done by this project, even though I admit it would actually be interesting as it would help in making the toolchain binaries even more system-independent. I am not sure how to achieve that though, so if you have some ideas, feel free to share them.

[cbarrete]

I don't know either, I have limited experience building toolchains from scratch. Some of the things that I am aware include:

• https://github.com/dzbarsky/static-clang, which provides static Clang binaries. It works great, but only handles the compiler part, so one still has to bring their own libc. I was hoping to source that from https://musl.cc/, but it's quite out of date at this point. As I understand it, they're using existing llvm + bazel infrastructure and running that to produce static binaries. I'm not clear on the details as there's a lot of complexity in aggregate.
• https://github.com/ziglang/zig/ provides C and C++ frontends (zig cc and zig c++). I can't use that at the moment due to a small bug, and it's definitely more custom, so maybe not something you'd be interested in (or at least it's not directly applicable).

I also looked at how Alpine and Void Linux handle their toolchains by unpacking their packages, but surprisingly, despite being musl distros, their compilers are dynamically linked against libc, so probably not much to learn from how they build their toolchains.