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Fri, 27 Sep 2024 18:56:17 +0000 From: Rasmus Villemoes To: Quentin Schulz Cc: Tom Rini , Simon Glass , u-boot@lists.denx.de, Quentin Schulz Subject: Re: [PATCH] cmd/mem.c: fix undefined behavior in mem cmp In-Reply-To: <20240927-cmd-mem-undefined-v1-1-56fa57d0927b@cherry.de> (Quentin Schulz's message of "Fri, 27 Sep 2024 18:37:43 +0200") References: <20240927-cmd-mem-undefined-v1-1-56fa57d0927b@cherry.de> Date: Fri, 27 Sep 2024 20:56:18 +0200 Message-ID: <87bk09kjsd.fsf@prevas.dk> User-Agent: Gnus/5.13 (Gnus v5.13) Content-Type: text/plain X-ClientProxiedBy: MM0P280CA0068.SWEP280.PROD.OUTLOOK.COM (2603:10a6:190:8::35) To DB9PR10MB7100.EURPRD10.PROD.OUTLOOK.COM (2603:10a6:10:45a::14) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: DB9PR10MB7100:EE_|PRAPR10MB7621:EE_ X-MS-Office365-Filtering-Correlation-Id: a401031b-7ab8-4e2d-60a7-08dcdf261128 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; ARA:13230040|376014|1800799024|52116014|366016|38350700014; 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And I assume U-Boot may want to be > compiled with clang/llvm? > > Let's fix that warning by casting the void pointer to a u8 pointer since > the size variable unit is byte. > > [1] https://gcc.gnu.org/onlinedocs/gcc/Pointer-Arith.html > No, let's please not. Try enabling -Wpointer-arith and see how much churn that would require all over the tree (doing it in this one place would be pointless), and all the casts would make the code much much harder to read. We do rely on lots of gcc extensions, and Clang has documented that it "aims to support a broad range of GCC extensions". Arithmetic on void is one of them, and that's not going to go away. Rasmus