Re: [PATCH V16 4/7] rust/powerpc: Set min rustc version for powerpc

On Tue, Jul 07, 2026 at 12:41:37PM +0530, Mukesh Kumar Chaurasiya wrote:
> On Tue, Jun 30, 2026 at 11:15:03AM +0530, Mukesh Kumar Chaurasiya wrote:
> > On Mon, Jun 29, 2026 at 11:11:44AM +0200, Miguel Ojeda wrote:
> > > On Mon, Jun 29, 2026 at 6:57 AM Mukesh Kumar Chaurasiya
> > > <[email protected]> wrote:
> > > >
> > > > Sure i'll bisect. Meanwhile i would still like to get this upstream.
> > > 
> > > It is very early on the cycle -- I would suggest bisecting first.
> > > 
> > > But it is up to ppc, of course.
> > > 
> > > Cheers,
> > > Miguel
> Hey Miguel,
> 
> I was able to bisect this. This got fixed in 1.87 with
> #![feature(asm_experimental_arch)].

On 1.85.0 though, with this feature allowed, the kernel gets built
perfectly without any need for 1.87.0.  You might want to require 1.87.0
only with altivec enabled, whereas on 32-bit we can build on 1.85.0 just
fine.

> 
> 1st commit that contributed towards this is
> e4f539ea17a3 ("Bump to version 1.87.0")
> 
> This caused another issue to come up while building
> 
> ```
> error: extern blocks must be unsafe
>   --> /home/mkchauras/.local/rustc-src/lib/rustlib/src/rust/library/core/src/../../stdarch/crates/core_arch/src/powerpc/vsx.rs:38:1
>    |
> 38 | / extern "C" {
> 39 | |     #[link_name = "llvm.ppc.altivec.vperm"]
> 40 | |     fn vperm(
> 41 | |         a: vector_signed_int,
> ...  |
> 44 | |     ) -> vector_signed_int;
> 45 | | }
>    | |_^
> ```
> 
> Which is fixed by 
> a78d1b092c9c ("Update stdarch")
> 
> Both these commits went in 1.87.0 and fixed the build.
> 
> Regards,
> Mukesh
> 
> > Sure, I'll bisect it first.
> > 
> > Regards,
> > Mukesh
> 

-- 
Link Mauve