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charset=UTF-8 Date: Fri, 11 Apr 2025 21:01:00 +0900 Message-Id: Cc: "Benno Lossin" , "Danilo Krummrich" , "Miguel Ojeda" , "Alex Gaynor" , "Boqun Feng" , "Gary Guo" , =?utf-8?q?Bj=C3=B6rn_Roy_Baron?= , "Andreas Hindborg" , "Alice Ryhl" , "Trevor Gross" , , Subject: Re: [PATCH] rust: alloc: allow coercion from `Box` to `Box` if T implements U From: "Alexandre Courbot" To: "Miguel Ojeda" X-Mailer: aerc 0.20.1-0-g2ecb8770224a References: <20250408-box_trait_objs-v1-1-58d8e78b0fb2@nvidia.com> In-Reply-To: X-ClientProxiedBy: TYWP286CA0022.JPNP286.PROD.OUTLOOK.COM (2603:1096:400:262::8) To CH2PR12MB3990.namprd12.prod.outlook.com (2603:10b6:610:28::18) Precedence: bulk X-Mailing-List: rust-for-linux@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: CH2PR12MB3990:EE_|SA3PR12MB7877:EE_ X-MS-Office365-Filtering-Correlation-Id: 3834cb62-5c71-43c0-c2d9-08dd78f08820 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|10070799003|1800799024|7416014|376014|366016; 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It is completely normal :) > >> I had some trouble finding how to 1) find out the minimum supported Rust >> version, and 2) how to build using a specific toolchain. > > For 1), the minimum versions for tools the Linux kernel uses is documente= d at: > > https://docs.kernel.org/process/changes.html#current-minimal-requirem= ents > > `min-tool-version.sh` is also fine, of course. > > For 2), similarly, it works like for other tools: either you override > your binary in the `$PATH` (that is easy with Rust with the command > you mention or simply with `rustup default X`), or you provide other > binaries via e.g. `make RUSTC=3D...` like you would do with `make > CC=3D...`. > >> I can send a patch against the Coding Guidelines adding a section to >> encourage testing against the minimum version and explain how to force a >> specific Rust version if you can confirm this would be helpful (and that >> min-tool-version.sh is the correct way to check the minimum supported >> Rust version). > > So that sort of thing is supposed to be documented in the "Submit > Checklist Addendum" section of the "Maintainer Entry Profile" document > (`P:` field in `MAINTAINERS`) of a given subsystem, and in particular > for Rust is at: > > https://rust-for-linux.com/contributing#submit-checklist-addendum > > I agree that linking from the Coding Guidelines or perhaps the root of > the Rust docs would probably help others to find it, since different > people go to different places when starting, so please feel free to > send a patch! Mmm upon reading this section again I agree it contains the needed information (even mentions `min-tool-version.sh`!) and can be found at the expected place, so I indeed don't see what more could be added to it. Thanks for the pointer and sorry again for overlooking!