From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from xry111.site (xry111.site [89.208.246.23]) by sourceware.org (Postfix) with ESMTPS id D33C43858404 for ; Wed, 10 Apr 2024 09:52:47 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org D33C43858404 Authentication-Results: sourceware.org; dmarc=pass (p=reject dis=none) header.from=xry111.site Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=xry111.site ARC-Filter: OpenARC Filter v1.0.0 sourceware.org D33C43858404 Authentication-Results: server2.sourceware.org; arc=none smtp.remote-ip=89.208.246.23 ARC-Seal: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1712742769; cv=none; b=QuRtNojmA1bjgNx4s8uFoUW+00MSYnKK1P+HaNlxOtmmK3Y8Wuc2UXq9wW/CAwM22eTbEJrcjH3DXpmd0WjNYc4rPxnmwzab0aLub+z1p40pwOzb/gYuYKfgxbmrCGf06+JGtgtE2zz5z7LKFYV54Jd2DS0mGoXJZbANiH+yRT4= ARC-Message-Signature: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1712742769; c=relaxed/simple; bh=EI4CdaZuN8oQVxZIOER4y4IstHUmMZ3G3na0E74kSoM=; h=DKIM-Signature:Message-ID:Subject:From:To:Date:MIME-Version; b=jYVw4q7IfXx4jfyV5GP09iHTtbSffuvHYAI6Dw9RrFC+JQ6+jZeMX98Q4jA+pHryWv4llwCCRYunWGEzW0FRSwftBpg4zMahpO5AlWGCdqZEQF9UyEGF3HA2if3N/mC5U8Rp1hq+GkNBvk53aGM98KOHJnMK91nw5OpMIrGgeow= ARC-Authentication-Results: i=1; server2.sourceware.org DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=xry111.site; s=default; t=1712742765; bh=EI4CdaZuN8oQVxZIOER4y4IstHUmMZ3G3na0E74kSoM=; h=Subject:From:To:Cc:Date:In-Reply-To:References:From; b=noDWjoRRF43ZIGB3ZXwtfblaPZcz2MjrToQX9EuSZ3rqcyPFvbtAZ07N8U3m+5Uye x+zpMAUYjERzhYtd0avWngG+VINOR2/AsVn7KHnFlCpL0JjcrQ8XdKgpycNNishgy3 rY3lQkupdwJt7yvyHvC9Gs27wqSWCcRnbyaOOzb8= Received: from [127.0.0.1] (unknown [IPv6:2001:470:683e::1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature ECDSA (P-384)) (Client did not present a certificate) (Authenticated sender: xry111@xry111.site) by xry111.site (Postfix) with ESMTPSA id 821F167563; Wed, 10 Apr 2024 05:52:44 -0400 (EDT) Message-ID: <5f1da8b7829b4b1a445aac2216f50aba2fb5dac5.camel@xry111.site> Subject: Re: optimizer discards sign information From: Xi Ruoyao To: LIU Hao , Alexander Monakov , stefan@franke.ms Cc: gcc-help@gcc.gnu.org Date: Wed, 10 Apr 2024 17:52:42 +0800 In-Reply-To: <2e2c1430-edfa-42ed-8713-cff56a2de64d@126.com> References: <016501da8b24$735d5170$5a17f450$@franke.ms> <5379650ad2582ae97c40ef1a78ded354033d2f71.camel@xry111.site> <0c105596-ecca-4936-84b0-b2f081b47bf2@126.com> <2e2c1430-edfa-42ed-8713-cff56a2de64d@126.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.52.0 MIME-Version: 1.0 X-Spam-Status: No, score=-1.8 required=5.0 tests=BAYES_00,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,LIKELY_SPAM_FROM,SPF_HELO_PASS,SPF_PASS,TXREP autolearn=no autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org List-Id: On Wed, 2024-04-10 at 17:51 +0800, LIU Hao wrote: > =E5=9C=A8 2024-04-10 17:44, Xi Ruoyao =E5=86=99=E9=81=93: > > You only get a "different result" when an undefined behavior > > happens, > > thus it **is** a valid point to say there is no wrong-code issue. > >=20 > > > It's a real bug. There are many PRs on bugzilla. > >=20 > > You may argue it's a missed-optimization, but we were discussing > > about > > wrong-code or not. >=20 > Nobody in this thread has been thinking it's wrong code. No, the OP is still thinking it's a wrong-code. See the latest reply from him. --=20 Xi Ruoyao School of Aerospace Science and Technology, Xidian University