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Date: Thu, 10 Apr 2025 15:26:49 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Cc: =?utf-8?B?UGF3ZcWC?= Anikiel <panikiel@google.com>,
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Subject: Re: [PATCH] x86/Kconfig: make CFI_AUTO_DEFAULT depend on !RUST
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On Thu, Apr 10, 2025 at 03:21:44PM +0200, Miguel Ojeda wrote:
> On Thu, Apr 10, 2025 at 3:09 PM Peter Zijlstra <peterz@infradead.org> wrote:
> >
> > Miguel, I cannot find this code in the kernel tree. Is this again
> > because Rust is not free-standing and relies on external code?
> 
> Yes, this comes from the `core` standard library. If it requires a
> change, then it needs to be fixed upstream.
> 
> > Can you please fix that. Building against external code that is not
> > under our control is a problem.
> 
> The only way to fix it would be to vendor the standard library, for
> each Rust compiler version -- and there is one new every 6 weeks.
> Thus, quite a few copies of it. Or keep patches (one per version) that
> we apply on the fly.

New compiler can't build old core?