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diff --git a/content/bootstrapGcc/15_pass_to_guix.md b/content/bootstrapGcc/15_pass_to_guix.md new file mode 100644 index 0000000..69666af --- /dev/null +++ b/content/bootstrapGcc/15_pass_to_guix.md @@ -0,0 +1,96 @@ +Title: Milestone (End?) - Bootstrapping path discovered +Date: 2024-07-02 +Category: +Tags: Bootstrapping GCC in RISC-V +Slug: bootstrapGcc15 +Lang: en +Summary: A RISC-V bootstrapping path path has been discovered. Now it's time + for the distros to catch up. + + +During the latest posts I described that we managed to build GCC using our +bootstrapping chain, and also that we built a modern GCC using our bootstrapped +one, but now, some connection work has been done. It's time to report on that. + +### Bootstrapping chain discovered + +In my [`commencement.scm`][commencement] project, I started working on a +bootstrapping path following Andrius Štikonas' steps in live-bootstrap. His +work is what is driving everything for several reasons: he knows how to do it +well and Guix has a handful of peculiarities that make this way more complex +than in live-bootstrap. + +First of all, live-bootstrap uses custom Makefiles for most of the projects, +that allows it to build things without relying on the feature detection that +the configure scripts normally use. We could do the same thing on Guix but +that would mean rewriting many packages from scratch and Guix package +definitions would become way more complex than what they are right now. + +Second, live-bootstrap is launched in some kind of a chrooted environment that +is shared by all steps. This means all the packages in it share the `/` folder, +and they can easily find other programs in `/bin` and libraries and stuff in +the folders expected by the FHS. In Guix we do *not* support the FHS, and our +packages are isolated, so we need to tweak the environment variables of the +packages in order to make them find the dependencies. This sometimes requires +patching the source of some packages, and here problems appear. + +The most heavily patched package in this regard is actually GCC. It needs to be +able to work well with our environment and that's not easy to do. This makes my +job harder. + +The good news is Andrius managed to build GCC 9.5 with the bootstrapping chain +in live-bootstrap and that means we discovered a full-source bootstrapping +path for RISC-V in 64 bit that is working **right now**. + +[commencement]: https://github.com/ekaitz-zarraga/commencement.scm + +### Time to make it reach a distro + +I managed to build GCC 9.5 with C support, using our bootstrapping path, and +that's more than nothing, but we are working with Efraim Flashner (one of the +Guix maintainers) to add full support for GCC 9.5 and also Janneke is working +on top of my `commencement.scm` file to merge it with the support they already +did for x86 (and was already done when I joined this effort). + +So, the efforts to include our work in Guix are currently happening and I don't +think there's much Andrius and I can do to help in this direction. The project +is on the hands of the people that know the best. + +#### Issues + +During the project we found some small inconveniences that we could not fix, +and those must be improved but they'll take long time, as they come from some +related projects. I'd love to say I have time, energy and knowledge to fix +those, but most of them are not under my control. + +First we have the problem we detected with Gash, that produces hangs in the +very first steps of the bootstrapping process. This is really hard to fix but +Timothy Sample, the project maintainer, is working on the issue. + +Second, some of the projects we use in the bootstrapping process require some +packaging skills I lack at this very moment, but they have been bootstrapped in +live-bootstrap so this can be done. The projects are `flex` and `bison`, and +maybe a couple more, but they are out of the scope of the project so I just +used the non-bootstrapped ones and left them as *to-do*s in the +`commencement.scm` file[^issue]. + +[^issue]: I also left those because we don't build them from source in Guix + yet. See <https://issues.guix.gnu.org/52311> + + +### What now, then? + +I think what to do next is pretty obvious now: handover to Guix. + +I'll open an issue in Guix in the following days where we'll discuss the +inclusion of this bootstrapping path in Guix in the following months, as the +other related issues are fixed and more steps are included in the chain. + +This handover process will take time because the bootstrapping path doesn't end +in a modern GCC, but in a *proper* GCC, GLibC, and some other packages that are +required for almost everything. Our discovery is enough to continue further, +but we didn't do that as our goal was to provide the RISC-V support in the +places were it wasn't ready. We have already shown that we did that. **Now I +guess it's time for the distros to catch up**. + +Of course, with our help. As always. |