[Mesa-dev] Rust drivers in Mesa

[Alexander Schlichte]

On 04.10.20 17:19, Alyssa Rosenzweig wrote:
> Cc'd.
>
> On Sun, Oct 04, 2020 at 03:17:28PM +0300, Michael Shigorin wrote:
>> For one, I'm porting ALT Linux onto e2k platform
>> (there's only an early non-optimizing version of
>> Rust port there by now), and we're maintaining repos
>> for aarch64, armv7hf, ppc64el, mipsel, and riscv64 either
>> -- none of which seem to be described as better than
>> "experimental" at http://doc.rust-lang.org/core/arch page
>> in terms of Rust support.
The correct page to check for platform support would be [1]. The page you
linked is just about exposing vendor-specific intrinsics within Rust itself,
not about what the rust compiler can target.

 From what I could find, both gcc and llvm appear to lack support for e2k, so
that's indeed problematic for the time being. As for the other architectures
you mentioned, those should correspond to:

aarch64-unknown-linux-gnu
armv7-unknown-linux-gnueabihf
powerpc64le-unknown-linux-gnu
mipsel-unknown-linux-gnu
riscv64gc-unknown-linux-gnu

All of which are tier 2 targets, can run cargo and rustc, and have full std
support. As Jacob already mentioned, aarch64 has a clear path towards tier 1
which is officially driven by ARM.

Platform support was also previously discussed at Linux Plumbers Conf back in
August [2], [3] with the main takeaway having been IIRC that adding support to
Rust isn't that hard once LLVM has support.

[1] https://doc.rust-lang.org/nightly/rustc/platform-support.html
[2] https://linuxplumbersconf.org/event/7/contributions/804/
[3] https://www.youtube.com/watch?v=FFjV9f_Ub9o&t=2065s