From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pl1-x62d.google.com (mail-pl1-x62d.google.com [IPv6:2607:f8b0:4864:20::62d]) by sourceware.org (Postfix) with ESMTPS id 8BB133858403 for ; Wed, 15 Sep 2021 15:36:59 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 8BB133858403 Received: by mail-pl1-x62d.google.com with SMTP id d18so1840728pll.11 for ; Wed, 15 Sep 2021 08:36:59 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:subject:to:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-transfer-encoding :content-language; bh=N0WAvfmWbk0YihRby2Xtn+fovUoTj/NdiWTsKk7CVXs=; b=0rm3YYWK28rw5EJZgBVNCYPHr3JhKfUbbEFeFCP3VYjHi1y2giBdQI2hiukM2ZXGGz 2P92wZZX3CvzuNgUWxuYe6nltdvrtw5jL98o8enxu851LsrP6qBKGIBO8J8YqWi+PXI+ UFajDgGJ3Jb7KbVEE452bcnPIQA4wwlSFRv1+tAET86gzq12GQ9q9WEj85PTeFCrMdrQ UWG2bGI9UxlQXCALMn5afBxP5UcjcaNUKAy0WwiISDnsxGzJ/bB7VVM6QZlriyiQrnI8 8KbFWaQecCf0b4dJd5L3j6laA1TD3UGP48SSU7+oqNKcT5uAhMAqrhfNF6MhfpJyd5nJ ELew== X-Gm-Message-State: AOAM533ytH524EEM+MZun8fz+qyVfB8U+WIpGKjE55zHkz7bjStpWZbW VXrpV14sgcLmZxl3v1OmA46BNdKq7+U= X-Google-Smtp-Source: ABdhPJxvZ08zrFxUh8oxyscIpdbmz/xdtMQTsOUsJQImH6PVf1k7WlaH4R/rCNydMYNjTJ8xepfrMQ== X-Received: by 2002:a17:902:b18b:b0:13a:354a:3e9d with SMTP id s11-20020a170902b18b00b0013a354a3e9dmr408519plr.36.1631720218402; Wed, 15 Sep 2021 08:36:58 -0700 (PDT) Received: from [192.168.1.24] (65-130-91-168.slkc.qwest.net. [65.130.91.168]) by smtp.gmail.com with ESMTPSA id 20sm323551pfi.170.2021.09.15.08.36.57 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 15 Sep 2021 08:36:58 -0700 (PDT) Subject: Re: [pushed] c++: don't warn about internal interference sizes To: Jason Merrill , gcc-patches@gcc.gnu.org References: <20210915153154.1111443-1-jason@redhat.com> From: Jeff Law Message-ID: <423c550a-1493-bf3e-7301-5544dbaae772@gmail.com> Date: Wed, 15 Sep 2021 09:36:56 -0600 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.14.0 MIME-Version: 1.0 In-Reply-To: <20210915153154.1111443-1-jason@redhat.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US X-Spam-Status: No, score=-3.2 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, FREEMAIL_FROM, NICE_REPLY_A, RCVD_IN_DNSWL_NONE, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on server2.sourceware.org X-BeenThere: gcc-patches@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 15 Sep 2021 15:37:00 -0000 On 9/15/2021 9:31 AM, Jason Merrill via Gcc-patches wrote: > Most any compilation on ARM/AArch64 was warning because the default L1 cache > line size of 32B was smaller than the default > std::hardware_constructive_interference_size of 64B. This is mostly due to > inaccurate --param l1-cache-line-size, but it's not helpful to complain to a > user that didn't set the values. > > gcc/cp/ChangeLog: > > * decl.c (cxx_init_decl_processing): Only warn about odd > interference sizes if they were specified with --param. I wonder if that'll fix the arm-linux build failures that started showing up recently: armeb-linux-gnueabi: : error: '--param constructive-interference-size=64' is greater than '--param l1-cache-line-size=32' [-Werror=interference-size] I expect the other arm- linux configurations would show it as well, but they're only run once a week in my tester and I don't think they've been run since the recent changes in this space. jeff