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AJvYcCVG97t205BJiHKdybdtt8ygv+K4paE0nPjgNKgPDLP/rvn4JstX5Pr6gKJFHnH+niNjIdxUMw7GQIBBc6fn6w==@vger.kernel.org X-Gm-Message-State: AOJu0YzknJcFgu1FOBL86AAzqmll/SbG/npTi3kOme1R9PN437DbA8F2 9R1SVbk/3JFIC/VPbo43fB6lrXq/7/m6HSvgbNyRoQ+VibabNVAbbEWr1Gi1Z10ImbzK/HXyt1f UNMPPdqtoV+Ju2iUbO2VOF6Lbom6C+Pc= X-Gm-Gg: ASbGncv2O1VgRXpxvMPBUyoGNs6TxmXa4n78aublLgz306q5Yh6rdcZyi9vweHMbB2l A1OYSV4CUQIY6ddADHEPD+kbI/rY0hzWdlY457lEYZ3/txKzo7atTCM5BKLBYsDUgL1o/+LL81l lMQD6QvYCKE22/YAibKmtw3TUPVUCi9yUT3Ebwm4Ggs9gtxdWQlxkeQOKcxTW0n2bW8uwTTd+W8 QLO42ViCIZ8SQ+we3IbeReHYySJOazcBHTT3vMox7ffgnBT85P9/BobU0jjGBBYpMejk83XoCym yzW9+WliKNJhS2Alx7Gf9PyaxQ== X-Google-Smtp-Source: AGHT+IFXtk/b+mBcCvYGj0Siyd7M1xdtwtm+rgr5hC4xpHP7Y4e1MWcNVn5VfaCSvjXJxZUU9Q7GdujGkw54EvBzg/k= X-Received: by 2002:a17:902:c40a:b0:25c:9a33:95fb with SMTP id d9443c01a7336-25d26d4c80fmr12553565ad.8.1757665674856; Fri, 12 Sep 2025 01:27:54 -0700 (PDT) Precedence: bulk X-Mailing-List: rust-for-linux@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 References: <20250911213157.GA1039411@joelbox2> <20250912025343.GA1376629@joelbox2> <4940aa5a-18d0-4bcd-9125-80f5a9920627@gmail.com> In-Reply-To: <4940aa5a-18d0-4bcd-9125-80f5a9920627@gmail.com> From: Miguel Ojeda Date: Fri, 12 Sep 2025 10:27:42 +0200 X-Gm-Features: AS18NWAksCJUI94FyECCBQ1v6323LDTQdfn2krc8zxB7QJ_YxljDTqr2dN0MuY0 Message-ID: Subject: Re: Printing with overflow checks can cause modpost errors To: Andrew Ballance Cc: Joel Fernandes , rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org, John Hubbard , Alexandre Courbot , Timur Tabi , Alistair Popple , Miguel Ojeda Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Fri, Sep 12, 2025 at 6:08=E2=80=AFAM Andrew Ballance wrote: > > The pointer passed is const so rustc should assume that the c side does > not change offset, but looks like rustc does not do that. That is not possible -- a const pointer does not guarantee the value will not be changed. Cheers, Miguel