From: brian m. carlson <sandals@crustytoothpaste.net>
Date: Thu, 30 Oct 2025 21:40:01 GMT
Subject: Re: [PATCH 3/3] rust: generate bindings via cbindgen
Message-ID: <aQPbMZpYZJQH_Fd6@fruit.crustytoothpaste.net>
In-Reply-To: <aQM07BQrGJocPKea@pks.im>

On 2025-10-30 at 09:50:36, Patrick Steinhardt wrote:
> For now that Rust version is 1.49, and that's enforced by our CI. The
> reason for this specific version is that it's the target version for the
> gcc-rs folks, so it may help currently-unsupported platforms to get
> support earlier.

As I mentioned a couple of times, gcc-rs uses the standard library of
Rust 1.49 since that's what it's targeting, and as a result it will not
support any platforms that Rust 1.49 didn't support since there isn't
standard library support for those platforms in that version.  It's like
trying to use a 2009 version of glibc and expecting it to work on
RISC-V, which was released in 2010—it simply won't.

That's why I was very clear at the Contributor's Summit that the message
we must send to platforms that do not have Rust is that they need to
port LLVM and target Rust that way, since that is the surest path to
success and to being able to get the necessary standard library changes
for things to work properly.  gcc-rs may be a viable solution in the
future, but it is not now, and absent substantial advances and an
order-of-magnitude faster development, it is unlikely to meet that
standard in time for Git 3.0.

So given that, I would propose that we target Rust 1.63 in conjunction
with my proposal.  I can send a patch to that effect later on.
-- 
brian m. carlson (they/them)
Toronto, Ontario, CA