From patchwork Thu May 22 12:42:11 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Laurent Pinchart X-Patchwork-Id: 23422 Return-Path: X-Original-To: parsemail@patchwork.libcamera.org Delivered-To: parsemail@patchwork.libcamera.org Received: from lancelot.ideasonboard.com (lancelot.ideasonboard.com [92.243.16.209]) by patchwork.libcamera.org (Postfix) with ESMTPS id 0B614C31E9 for ; Thu, 22 May 2025 12:42:21 +0000 (UTC) Received: from lancelot.ideasonboard.com (localhost [IPv6:::1]) by lancelot.ideasonboard.com (Postfix) with ESMTP id 2321568D8E; Thu, 22 May 2025 14:42:20 +0200 (CEST) Authentication-Results: lancelot.ideasonboard.com; dkim=pass (1024-bit key; unprotected) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="qyDt8Tvn"; dkim-atps=neutral Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [213.167.242.64]) by lancelot.ideasonboard.com (Postfix) with ESMTPS id 79DB368D8B for ; Thu, 22 May 2025 14:42:18 +0200 (CEST) Received: from pendragon.ideasonboard.com (179.218-130-109.adsl-dyn.isp.belgacom.be [109.130.218.179]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 53114605; Thu, 22 May 2025 14:41:56 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1747917716; bh=EZA6bO6ZbG8OGe+oSENiCSZJXrbAXhQC80FiJUCqYOo=; h=From:To:Cc:Subject:Date:From; b=qyDt8TvncMBi8EUArE3JTY5GYt7pGNKnToGNrart9d9+f/FK3Qfpnb7aQkOJ5qZx2 d4saFrPweRiLIvVB1zns4gkG+sdinUJJH9ooIJy51welsZ1lmsH4AYCJpTdZmie9N3 cup2u56G8/N7qlv+CPJ19LgdDlqz2px+graCtCYY= From: Laurent Pinchart To: libcamera-devel@lists.libcamera.org Cc: Stefan Klug , Milan Zamazal Subject: [PATCH] libcamera: matrix: Fix compilation error in inverse() function 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 X-BeenThere: libcamera-devel@lists.libcamera.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: libcamera-devel-bounces@lists.libcamera.org Sender: "libcamera-devel" Some gcc versions report uninitialized variable usage: In member function ‘constexpr T& libcamera::Span::operator[](size_type) const [with T = unsigned int]’, 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, inlined from ‘bool libcamera::matrixInvert(Span, Span, unsigned int, Span, Span) [with T = float]’ at ../../src/libcamera/matrix.cpp:255:14: ../../include/libcamera/base/span.h:362:76: error: ‘row’ may be used uninitialized [-Werror=maybe-uninitialized] 362 | constexpr reference operator[](size_type idx) const { return data()[idx]; } | ~~~~~~^ ../../src/libcamera/matrix.cpp: In function ‘bool libcamera::matrixInvert(Span, Span, unsigned int, Span, Span) [with T = float]’: ../../src/libcamera/matrix.cpp:232:30: note: ‘row’ was declared here 232 | unsigned int row; | ^~~ This is a false positive. Fix it by initializing the variable when declaring it. Fixes: 6287ceff5aba ("libcamera: matrix: Add inverse() function") Signed-off-by: Laurent Pinchart Reviewed-by: Kieran Bingham Tested-by: Barnabás Pőcze Tested-by: Milan Zamazal --- src/libcamera/matrix.cpp | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) base-commit: efdbe3969841e342c30dfdced38b6ad9ad55dccf diff --git a/src/libcamera/matrix.cpp b/src/libcamera/matrix.cpp index ed22263b58f8..b7c07e896538 100644 --- a/src/libcamera/matrix.cpp +++ b/src/libcamera/matrix.cpp @@ -229,7 +229,7 @@ bool matrixInvert(Span dataIn, Span dataOut, unsigned int dim, * Locate the next pivot. To improve numerical stability, use * the row with the largest value in the pivot's column. */ - unsigned int row; + unsigned int row = pivot; T maxValue{ 0 }; for (unsigned int i = pivot; i < dim; ++i) {