{"id":23422,"url":"https://patchwork.libcamera.org/api/1.1/patches/23422/?format=json","web_url":"https://patchwork.libcamera.org/patch/23422/","project":{"id":1,"url":"https://patchwork.libcamera.org/api/1.1/projects/1/?format=json","name":"libcamera","link_name":"libcamera","list_id":"libcamera_core","list_email":"libcamera-devel@lists.libcamera.org","web_url":"","scm_url":"","webscm_url":""},"msgid":"<20250522124211.2229-1-laurent.pinchart@ideasonboard.com>","date":"2025-05-22T12:42:11","name":"libcamera: matrix: Fix compilation error in inverse() function","commit_ref":"516f365670235f9dac97defa1b586d0503f8e310","pull_url":null,"state":"accepted","archived":false,"hash":"70ed10b87b00166b0eac0acadcb9911f08952c45","submitter":{"id":2,"url":"https://patchwork.libcamera.org/api/1.1/people/2/?format=json","name":"Laurent Pinchart","email":"laurent.pinchart@ideasonboard.com"},"delegate":null,"mbox":"https://patchwork.libcamera.org/patch/23422/mbox/","series":[{"id":5189,"url":"https://patchwork.libcamera.org/api/1.1/series/5189/?format=json","web_url":"https://patchwork.libcamera.org/project/libcamera/list/?series=5189","date":"2025-05-22T12:42:11","name":"libcamera: matrix: Fix compilation error in inverse() function","version":1,"mbox":"https://patchwork.libcamera.org/series/5189/mbox/"}],"comments":"https://patchwork.libcamera.org/api/patches/23422/comments/","check":"pending","checks":"https://patchwork.libcamera.org/api/patches/23422/checks/","tags":{},"headers":{"Return-Path":"","X-Original-To":"parsemail@patchwork.libcamera.org","Delivered-To":"parsemail@patchwork.libcamera.org","Received":["from lancelot.ideasonboard.com (lancelot.ideasonboard.com\n\t[92.243.16.209])\n\tby patchwork.libcamera.org (Postfix) with ESMTPS id 0B614C31E9\n\tfor ;\n\tThu, 22 May 2025 12:42:21 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 2321568D8E;\n\tThu, 22 May 2025 14:42:20 +0200 (CEST)","from perceval.ideasonboard.com (perceval.ideasonboard.com\n\t[213.167.242.64])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id 79DB368D8B\n\tfor ;\n\tThu, 22 May 2025 14:42:18 +0200 (CEST)","from pendragon.ideasonboard.com\n\t(179.218-130-109.adsl-dyn.isp.belgacom.be [109.130.218.179])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id 53114605;\n\tThu, 22 May 2025 14:41:56 +0200 (CEST)"],"Authentication-Results":"lancelot.ideasonboard.com; dkim=pass (1024-bit key;\n\tunprotected) header.d=ideasonboard.com header.i=@ideasonboard.com\n\theader.b=\"qyDt8Tvn\"; dkim-atps=neutral","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1747917716;\n\tbh=EZA6bO6ZbG8OGe+oSENiCSZJXrbAXhQC80FiJUCqYOo=;\n\th=From:To:Cc:Subject:Date:From;\n\tb=qyDt8TvncMBi8EUArE3JTY5GYt7pGNKnToGNrart9d9+f/FK3Qfpnb7aQkOJ5qZx2\n\td4saFrPweRiLIvVB1zns4gkG+sdinUJJH9ooIJy51welsZ1lmsH4AYCJpTdZmie9N3\n\tcup2u56G8/N7qlv+CPJ19LgdDlqz2px+graCtCYY=","From":"Laurent Pinchart ","To":"libcamera-devel@lists.libcamera.org","Cc":"Stefan Klug ,\n\tMilan Zamazal ","Subject":"[PATCH] libcamera: matrix: Fix compilation error in inverse()\n\tfunction","Date":"Thu, 22 May 2025 14:42:11 +0200","Message-ID":"<20250522124211.2229-1-laurent.pinchart@ideasonboard.com>","X-Mailer":"git-send-email 2.49.0","MIME-Version":"1.0","Content-Type":"text/plain; charset=UTF-8","Content-Transfer-Encoding":"8bit","X-BeenThere":"libcamera-devel@lists.libcamera.org","X-Mailman-Version":"2.1.29","Precedence":"list","List-Id":"","List-Unsubscribe":",\n\t","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n\t","Errors-To":"libcamera-devel-bounces@lists.libcamera.org","Sender":"\"libcamera-devel\" "},"content":"Some gcc versions report uninitialized variable usage:\n\nIn member function ‘constexpr T& libcamera::Span::operator[](size_type) const [with T = unsigned int]’,\n inlined from ‘void libcamera::matrixInvert(Span, Span, unsigned int, Span, Span)::MatrixAccessor::swap(unsigned int, unsigned int) [with T = float]’ at ../../src/libcamera/matrix.cpp:194:13,\n inlined from ‘bool libcamera::matrixInvert(Span, Span, unsigned int, Span, Span) [with T = float]’ at ../../src/libcamera/matrix.cpp:255:14:\n../../include/libcamera/base/span.h:362:76: error: ‘row’ may be used uninitialized [-Werror=maybe-uninitialized]\n 362 | constexpr reference operator[](size_type idx) const { return data()[idx]; }\n | ~~~~~~^\n../../src/libcamera/matrix.cpp: In function ‘bool libcamera::matrixInvert(Span, Span, unsigned int, Span, Span) [with T = float]’:\n../../src/libcamera/matrix.cpp:232:30: note: ‘row’ was declared here\n 232 | unsigned int row;\n | ^~~\n\nThis is a false positive. Fix it by initializing the variable when\ndeclaring it.\n\nFixes: 6287ceff5aba (\"libcamera: matrix: Add inverse() function\")\nSigned-off-by: Laurent Pinchart \n---\n src/libcamera/matrix.cpp | 2 +-\n 1 file changed, 1 insertion(+), 1 deletion(-)\n\n\nbase-commit: efdbe3969841e342c30dfdced38b6ad9ad55dccf","diff":"diff --git a/src/libcamera/matrix.cpp b/src/libcamera/matrix.cpp\nindex ed22263b58f8..b7c07e896538 100644\n--- a/src/libcamera/matrix.cpp\n+++ b/src/libcamera/matrix.cpp\n@@ -229,7 +229,7 @@ bool matrixInvert(Span dataIn, Span dataOut, unsigned int dim,\n \t\t * Locate the next pivot. To improve numerical stability, use\n \t\t * the row with the largest value in the pivot's column.\n \t\t */\n-\t\tunsigned int row;\n+\t\tunsigned int row = pivot;\n \t\tT maxValue{ 0 };\n \n \t\tfor (unsigned int i = pivot; i < dim; ++i) {\n","prefixes":[]}