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[74.125.82.179]) by smtp.gmail.com with ESMTPSA id 98e67ed59e1d1-35d9caadaacsm2753700a91.4.2026.03.30.05.10.23 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 30 Mar 2026 05:10:23 -0700 (PDT) Received: by mail-dy1-f179.google.com with SMTP id 5a478bee46e88-2c54c68db4dso2226343eec.0 for ; Mon, 30 Mar 2026 05:10:23 -0700 (PDT) X-Forwarded-Encrypted: i=1; AJvYcCV5fkVUoX9P2QgQUIVWbcqw/x1SQVC+b+xK0YN+J6YSCsd41bpWfQc/G0fgIglJzvghLDFTdmy8DQ==@kvack.org X-Received: by 2002:a05:6122:1824:b0:56a:e46f:2cfa with SMTP id 71dfb90a1353d-56d4a5f2e5cmr4217124e0c.12.1774872216490; Mon, 30 Mar 2026 05:03:36 -0700 (PDT) MIME-Version: 1.0 References: <20260322192159.88138-1-ojeda@kernel.org> <20260323000327.111235-1-ojeda@kernel.org> <9cf5a94c-0f37-446c-b63d-ddac5674d220@gmail.com> <641592e3-2354-4238-9eb8-a1f5c2a13126@app.fastmail.com> <93439e91-cf81-477b-b880-a813bb01ad7c@app.fastmail.com> In-Reply-To: <93439e91-cf81-477b-b880-a813bb01ad7c@app.fastmail.com> From: Geert Uytterhoeven Date: Mon, 30 Mar 2026 14:03:24 +0200 X-Gmail-Original-Message-ID: X-Gm-Features: AQROBzBixIQPiuCOL0pIFbgyC_M26WMZwTpKOw623Sg5KUyDyMzQqEZKs9RSoco Message-ID: Subject: Re: [PATCH v2 0/3] Inline helpers into Rust without full LTO To: Arnd Bergmann Cc: Russell King , Christian Schrefl , Miguel Ojeda , Alice Ryhl , Ard Biesheuvel , Jamie Cunliffe , Will Deacon , Catalin Marinas , Miguel Ojeda , Andreas Hindborg , acourbot@nvidia.com, Andrew Morton , Anton Ivanov , =?UTF-8?Q?Bj=C3=B6rn_Roy_Baron?= , Boqun Feng , Danilo Krummrich , David Gow , Gary Guo , Johannes Berg , Justin Stitt , linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-um@lists.infradead.org, llvm@lists.linux.dev, Benno Lossin , Mark Rutland , mmaurer@google.com, Bill Wendling , Nathan Chancellor , Nick Desaulniers , Nicolas Schier , Nicolas Schier , Peter Zijlstra , Richard Weinberger , rust-for-linux@vger.kernel.org, Trevor Gross , "Uladzislau Rezki (Sony)" , John Paul Adrian Glaubitz Content-Type: text/plain; charset="UTF-8" X-Rspamd-Queue-Id: C4A544000C X-Stat-Signature: uadoo5yisw6i3owpk3ieyhywsq639t9d X-Rspam-User: X-Rspamd-Server: rspam04 X-HE-Tag: 1774872624-123894 X-HE-Meta: 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 nohO/1+H l+s+JqvJ3sPl6At8aiy4aIOhiB+ji/angs3scWGhsFFA/smFHjvo4W+mRfa5UC3eLj+A+tIPOK9TjjM1wM+mUWEG4lorzSeHNdaLTVeKR7UwTmY7tfnoBHMFB72srqUEpFpavNRRxPbK14lsFUxj6uF52JfVCJ/jJk0o80YlbHLD46r16tryY7HUC9B84JFsKmYO92BXfhqsN0VeYlrBlDgs2A7NVrZHHOYlmi+yAV2cqPyuipBRfTE5BptgXqDmd0/sbiijwLz9UY6IPgNh3xGBK+2DMIBJYy2DLdaAHxWIhndLPGvE5gwKsLZ4GSL7dKYzJVFqB1puwx3LkdiORUK2VXHHdesRDUizFkeXlYQZ48r3I8KABLC6cgPdH7oAIGuGDdcNRcb/pGt2TnL+0I0GsTxDbwdC8L2/sLh6aPVOivZCMexdEbgFH2H8PMLWFUGAZdGELG6wKcYrGkk+nJ/AZv0P6+xwIzNOBrvJgQ391IbQ= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: Hi Arnd, On Fri, 27 Mar 2026 at 10:02, Arnd Bergmann wrote: > On Fri, Mar 27, 2026, at 08:56, Geert Uytterhoeven wrote: > >> I noticed a similar issue with m68k-linux, which has a bitfield > >> alignment different from anything else on gcc, but uses the normal > >> behavior on clang. > > > > Ugh, I wasn't aware of that. Adrian, did you know? > > To clarify, this illustrates what I mean here: > > echo 'struct { short a : 3; short b :15; short c :14; } x; int y = sizeof(x);' | m68k-linux-gcc -xc - -S -o- > > this produces '4' on m68k-linux-gcc, but '6' everywhere else. I originally > thought this was related to this 2009 change in both compilers Oh, now I remember. AFAIK (holding wood and a rabbit leg) we don't have any bitfield members spanning multiple base type instances in the kernel. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds