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AFNElJ+AGLF3rUjfqklgz0g4LKQ77+e1TXQnH7WuYYZdz3ZL6TG6JS7mjOcZkBTv1wKe3zyU5jZpKyeDNeNhu5sDMw==@vger.kernel.org X-Gm-Message-State: AOJu0Yy5FIRi76qCtc42JZ97TvXCADV0gUwemzSsXCqgSGbTBrWD0xdE 7UHKSB3YIetbBm3LqdBh2sOjNW7rT8p1/NefkCXwRfjfo0fSO4F+q8zC9gn39pS0MB2LrxzRrkC PwvqdGTHLlLW1mM6CEA== X-Received: from wmsk6-n2.prod.google.com ([2002:a05:600d:8486:20b0:490:3fd8:77de]) (user=aliceryhl job=prod-delivery.src-stubby-dispatcher) by 2002:a05:600c:6995:b0:48f:d5b8:5b07 with SMTP id 5b1f17b1804b1-4922ffb64e2mr31069555e9.20.1781595580272; Tue, 16 Jun 2026 00:39:40 -0700 (PDT) Date: Tue, 16 Jun 2026 07:39:39 +0000 In-Reply-To: Precedence: bulk X-Mailing-List: rust-for-linux@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260608181451.3734956-1-japo@linux.ibm.com> <20260608181451.3734956-7-japo@linux.ibm.com> <20260615164013.GA249489@ax162> Message-ID: Subject: Re: [PATCH v6 6/6] s390: Enable Rust support From: Alice Ryhl To: Miguel Ojeda Cc: Nathan Chancellor , Jan Polensky , hca@linux.ibm.com, gor@linux.ibm.com, agordeev@linux.ibm.com, ojeda@kernel.org, peterz@infradead.org, jpoimboe@kernel.org, jbaron@akamai.com, borntraeger@linux.ibm.com, svens@linux.ibm.com, boqun@kernel.org, gary@garyguo.net, bjorn3_gh@protonmail.com, lossin@kernel.org, a.hindborg@kernel.org, tmgross@umich.edu, dakr@kernel.org, rostedt@goodmis.org, ardb@kernel.org, linux-s390@vger.kernel.org, rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable On Mon, Jun 15, 2026 at 06:45:26PM +0200, Miguel Ojeda wrote: > On Mon, Jun 15, 2026 at 6:40=E2=80=AFPM Nathan Chancellor wrote: > > > > With Rust 1.96.0, I see the following warning several times when > > building Rust code in -next: > > > > warning: unstable feature specified for `-Ctarget-feature`: `backchai= n` > > | > > =3D note: this feature is not stably supported; its behavior can ch= ange in the future > > > > warning: 1 warning emitted > > > > I assume this is expected? If so, is there a way to silence this warnin= g? >=20 > Yes, it seems so -- please see this thread: >=20 > https://lore.kernel.org/rust-for-linux/CANiq72m4GVWFYqnxNtCHTPu7XcGewHB= 5LNwOoayTfnXs9pPbNg@mail.gmail.com/ >=20 > If they are OK with it, then I guess it is fine, but it does mean CIs > can suffer a bit from it. Since fixing this requires a change in rustc to recognize the backchain target feature, has this work been started? I think that for stuff like this, we should make to at least start working on fixing the warning so that we don't emit a warning forever. Alice