Re: [PATCH] rust: kasan/kbuild: fix missing flags on first build

[Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>]

On Wed, Apr 9, 2025 at 11:35 PM Matthew Maurer <mmaurer@google.com> wrote:
>
> The problem with this change is that some `rustc` flags will only be
> valid on some platforms. For example, if we check if a

Indeed -- this limitation is acknowledged in the commit message. The
priority is fixing the issue, not future features/needs, so I went
with this.

In any case, if we need to test a flag that requires the target, it is
likely we can do the check based on the Rust version, the
architecture, the Rust's LLVM version, etc.

As for `target.json`s, the plan is indeed to get rid of them, since
they are permanently unstable. So any features used by the
`target.json`s need to be requested to upstream Rust (e.g. flags) so
that we can do the same without a custom target specification, so that
eventually we can remove all of them (and thus `rustc-option` will
work in all cases again).

Thanks for taking a look!

Cheers,
Miguel