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

On Tue, Jul 07, 2026 at 12:20:59PM +0200, Link Mauve wrote:
> 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.
> 
Even without altivec and vsx disabled, It's not building for ppc64le.

Regards,
Mukesh

> > 
> > 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