From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 102251 invoked by alias); 18 Sep 2017 06:09:31 -0000 Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-alpha-owner@sourceware.org Received: (qmail 102238 invoked by uid 89); 18 Sep 2017 06:09:30 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-0.9 required=5.0 tests=BAYES_00,KAM_LAZY_DOMAIN_SECURITY,RP_MATCHES_RCVD,SPF_HELO_PASS autolearn=no version=3.3.2 spammy=site X-HELO: mx1.redhat.com DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 8945D5AFD9 Authentication-Results: ext-mx10.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx10.extmail.prod.ext.phx2.redhat.com; spf=fail smtp.mailfrom=fweimer@redhat.com Subject: Re: [PATCH 4/9] Sync scratch_buffer with gnulib To: Adhemerval Zanella , libc-alpha@sourceware.org Cc: Paul Eggert References: <1504643122-14874-1-git-send-email-adhemerval.zanella@linaro.org> <1504643122-14874-5-git-send-email-adhemerval.zanella@linaro.org> From: Florian Weimer Message-ID: <3e95c32d-2311-c791-1df2-5b1883486d0b@redhat.com> Date: Mon, 18 Sep 2017 06:09:00 -0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.3.0 MIME-Version: 1.0 In-Reply-To: <1504643122-14874-5-git-send-email-adhemerval.zanella@linaro.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit X-SW-Source: 2017-09/txt/msg00669.txt.bz2 On 09/05/2017 10:25 PM, Adhemerval Zanella wrote: > - char __space[1024] > - __attribute__ ((aligned (__alignof__ (max_align_t)))); > + max_align_t __space[(1023 + sizeof (max_align_t)) / sizeof (max_align_t)]; This change needs a declaration from the GCC folks (probably from Richard Biener) that it does not break aliasing analysis. The old code uses a GCC extension (writing to a char array changes its dynamic type); it is not valid C. I don't know if the GCC extension also applies if the storage site is declared with a non-char type. Thanks, Florian