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charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Rspamd-Queue-Id: 6530340008 X-Stat-Signature: cgpsommqp7iw6dm8um9gpjb4zipxmabe X-Rspam-User: X-Rspamd-Server: rspam07 X-HE-Tag: 1774503294-731554 X-HE-Meta: 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 BAY9eb/l PTJTyoHKzKExjT1k= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: Le 23/03/2026 à 3:21 AM, Miguel Ojeda a écrit : > On Tue, 03 Feb 2026 11:34:07 +0000 Alice Ryhl wrote: >> >> To get rid of these helper symbols, provide functionality to inline >> helpers into Rust using llvm-link. This option complements full LTO, by >> being much cheaper and avoiding incompatibility with BTF. > > I have been testing this. I think we can go ahead with it, with a few > notes. > > I will reply to a couple other bindings in separate emails to avoid > spamming people too much. > > - I will mark the Kconfig option as "(EXPERIMENTAL)", since that is > what the commit message says and it allows us to be a bit > conservative. > > > - Clang passes `-Werror=unused-command-line-argument`, which means > under arm (i.e. 32-bit) we get: > > clang: error: argument unused during compilation: '-U arm' [-Werror,-Wunused-command-line-argument] > > And under UML I see: > > clang: error: argument unused during compilation: '-I ./arch/um/include/shared' [-Werror,-Wunused-command-line-argument] > clang: error: argument unused during compilation: '-I ./arch/x86/um/shared' [-Werror,-Wunused-command-line-argument] > clang: error: argument unused during compilation: '-I ./arch/um/include/shared/skas' [-Werror,-Wunused-command-line-argument] > > So we would need e.g. `-Wno-unused-command-line-argument` there > close to the `-Wno-override-module` one, unless Kbuild or > ClangBuiltLinux thinks it is important to keep it for this case. > > On the other hand, regardless of whether we fix this (and another > issue in a separate email found thanks to the UML build), we could > instead add `depends on` listing explicitly the architectures where > this is going to be actually tested. That way maintainers can decide > whether they want to support it when they are ready. Thoughts? > > Cc'ing Nathan, Nicolas, Nick, Bill, Justin, David, UML, ARM. I'm quite happy personally to just have -Wno-unused-command-line-argument here, given that it otherwise is working pretty well on UML and 32-bit UML. That being said, I expect it won't get a lot of testing (regardless of architecture) while it's hidden behind CONFIG_EXPERT. Cheers, -- David