Re: [PATCH v3 0/4] s390: Enable Rust support and add required arch glue

[Miguel Ojeda]

On Wed, May 27, 2026 at 12:38 PM Alice Ryhl <aliceryhl@xxxxxxxxxx> wrote:
>
> Based on some very quick research, it looks like enabling the backchain
> target feature does not affect the ABI in the sense that mixing together
> object files with and without this option will still work. If that's the
> case, we can add this to the list of known target features for this
> target in rustc, which will silence this warning.
>
> (If it affects the ABI in a breaking manner, it needs to be added as a
> separate flag rather than being added as part of the -Ctarget-feature
> flag.)

Yes, from the different discussions what I saw is that the issue was
mixing it with `-Zpacked-struct`, but that is already rejected by the
compiler. They also discussed whether it should have been its own
flag, though.

Cheers,
Miguel