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References: <20221205214454.2542888-1-gary@garyguo.net>
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From:   Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Date:   Tue, 17 Jan 2023 00:33:24 +0100
Message-ID: <CANiq72kjaNpc_e6b0fetviJAcWBAitnD+mNmJV5Xr15rFubY9w@mail.gmail.com>
Subject: Re: [PATCH v3] rust: compiler_builtins: make stubs non-global
To:     Gary Guo <gary@garyguo.net>
Cc:     Miguel Ojeda <ojeda@kernel.org>,
        Alex Gaynor <alex.gaynor@gmail.com>,
        Wedson Almeida Filho <wedsonaf@gmail.com>,
        Boqun Feng <boqun.feng@gmail.com>,
        =?UTF-8?Q?Bj=C3=B6rn_Roy_Baron?= <bjorn3_gh@protonmail.com>,
        rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org
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On Mon, Dec 5, 2022 at 10:45 PM Gary Guo <gary@garyguo.net> wrote:
>
> Currently we define a number of stubs for compiler-builtin intrinsics
> that compiled libcore generates. The defined stubs are weak so they will
> not conflict with genuine implementation of these intrinsics, but their
> effect is global and will cause non-libcore code that accidently
> generate these intrinsics calls compile and bug on runtime.
>
> Instead of defining a stub that can affect all code, this patch uses
> objcopy's `--redefine-sym` flag to redirect these calls (from libcore
> only) to a prefixed version (e.g. redirect `__multi3` to `__rust_multi3`),
> so we can define panciking stubs that are only visible to libcore.
>
> This patch was previously discussed on GitHub [1].
>
> Link: https://github.com/Rust-for-Linux/linux/pull/779 [1]
> Signed-off-by: Gary Guo <gary@garyguo.net>

Applied to rust-next, thanks all!

Cheers,
Miguel