From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from fencepost.gnu.org (fencepost.gnu.org [IPv6:2001:470:142:3::e]) by sourceware.org (Postfix) with ESMTPS id CF89D3858413 for ; Wed, 18 May 2022 16:56:19 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org CF89D3858413 Received: from eggs.gnu.org ([2001:470:142:3::10]:49718) by fencepost.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nrMyB-0007gf-4A for gcc-help@gnu.org; Wed, 18 May 2022 12:56:19 -0400 Received: from mail-ej1-x62e.google.com ([2a00:1450:4864:20::62e]:44982) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1nrMy8-0001mk-Ji for gcc-help@gnu.org; Wed, 18 May 2022 12:56:17 -0400 Received: by mail-ej1-x62e.google.com with SMTP id i19so4950492eja.11 for ; Wed, 18 May 2022 09:56:14 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:from:date:message-id:subject:to; bh=GihZ1YnlWGKCYxO1LrMIS1eyLvsdmuALX0tD4/jwhoE=; b=TVqHzdHfBRLXgdjbFIssCOmxpTEBuzH0ARsUZ8zD0T9YuGeHpbSJI5RFtXa7KhoZT8 oXxOoP9S/I4CkLB++4GX1giA+CJrhzR6bpwXDJ2WxqidMi+o1ke69Vqkn+jPe4tpimVl dAC+Y9inxQrvs6hm6FnvTWekAZbc+vTiRrN+AGS9Dq9EewG3/09ySxwatF4NKoHyyG9J HxM7E0uGzltgMx7Sza/Vj/0oxV3v0WA53DdrIvmEowm54FiUWZMLZZZQGUR7vP93WPCf PIOIIvGNtAFcbBiw+iiaxfuODNHxK48w9efBbkbCq2Qht9iu9sP4B8Jh/McdGCSl10kA n6Ow== X-Gm-Message-State: AOAM532/98BSTJGLjGCNq0sUTtTT4Yev6vS+DbqNLXdOM50GBwZbRySB BNSeB6mQ3G8DWNKv90ujkSO0eYe3jjPPrVhd68+l9qOrkZg= X-Google-Smtp-Source: ABdhPJzsQDsddGRL4c+gNEqcpsEC1oECUVjfhPzyRFGwIoBQ558ZwvM5P+mdct2MXq/zDE/ednQs9NOSuKTWdWeeeck= X-Received: by 2002:a17:907:8a17:b0:6f4:4b56:f550 with SMTP id sc23-20020a1709078a1700b006f44b56f550mr484005ejc.720.1652892972608; Wed, 18 May 2022 09:56:12 -0700 (PDT) MIME-Version: 1.0 From: Tom Kacvinsky Date: Wed, 18 May 2022 12:56:01 -0400 Message-ID: Subject: GCC 12.1, -isystem, -Wsystem-headers, and -Wmaybe-uninitialized To: gcc-help@gnu.org Received-SPF: pass client-ip=2a00:1450:4864:20::62e; envelope-from=tkacvins@gmail.com; helo=mail-ej1-x62e.google.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FREEMAIL_FROM=0.001, HTML_MESSAGE=0.001, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-Spam-Status: No, score=0.0 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, FREEMAIL_FORGED_FROMDOMAIN, FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS, HTML_MESSAGE, SPF_HELO_NONE, SPF_PASS, TXREP, T_SCC_BODY_TEXT_LINE autolearn=no autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org Content-Type: text/plain; charset="UTF-8" X-Content-Filtered-By: Mailman/MimeDel 2.1.29 X-BeenThere: gcc-help@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-help mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 18 May 2022 16:56:20 -0000 We were happily using -Wall -Wextra -Werror with GCC 8.3.0 and -isystem for Boost header files to squelch any warnings that would come out of Boost. I recently switched to GCC 12.1 and now we are getting -Wmaybe-uninitialized errors out of Boost. So I am not sure if -Wsystem-headers was not part of -Wall -Wextra in GCC 8.3.0 but is now part of GCC 12.1.0. Optimization level plays a role in this. With -O0 (GCC 12.1), the warning does not happen, but with -O3, it does. So I am not sure of the interaction between optimization, -Wall -Wextra, -Wsystem-headers, and GCC 8.3.0 and GCC 12.1.0. Any ideas? Thanks, Tom