Re: Aarch64 build of rust-1.39.0 fails

[Maxim Cournoyer <maxim.cournoyer@gmail.com>]

Hi Denis,

Denis 'GNUtoo' Carikli <GNUtoo@cyberdimension.org> writes:

> On Tue, 04 Jan 2022 17:22:02 -0500
> Maxim Cournoyer <maxim.cournoyer@gmail.com> wrote:
>
>> Hi Denis,
> Hi,
>
>> Note that you'll want to use the latest commit available of mrustc, or
>> something recent enough like this in (gnu packages rust) as it
>> includes recent fixes to the (still failing) i686 build:
> With ./build-1.39.0.sh in mrustc, some help from #mrustc, and some local
> patches, I was able to get it build under 4GiB of RAM per process with
> an x86_64 kernel (by removing -O2 and -g), but it fails for 3GiB of RAM
> per process (i686 kernel) no mater what options are passed to it.

Thank you for doing the experiment and sharing the result!  I've relayed
it to mrustc's author here:
https://github.com/thepowersgang/mrustc/issues/78, I hope you don't
mind.

> My issue is that claws-mail now depend on rust (it didn't before). As
> several other pakcages also fails on i686 (failing tests), and that I
> also hit a Guix bug, it's hard for me to fix it as everything is
> broken and I need to do workarounds on workarounds.

The situation with Rust on Guix is far from satisfactory, and the usage
of Rust continues to expand, we'll have to find solutions.  GCC-rust
seems like a good candidate to help us bootstrap for more platforms, but
it isn't ready yet.  mrustc is the current best option; cross-building
rust could be another thing to do (there's a wip-cross-built-rust branch
that I had started to explore doing this), but it's a messier path.

> What do I need to revert (locally?) to make claws-mail not depend on
> rust (for i686)?

I don't see this relationship locally:

$ guix graph --path claws-mail rust
$ guix describe
5b95cad85018e64f2a34ef950dd2e5434d07cfc0

But looking at the package definition, it explicitly depends on librsvg,
which is a Rust-powered library.  You could try to make this input
conditional (e.g., add it only when the system is x86_64), if claws-mail
can be built without it.

Thanks,

Maxim