From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id DD3623858412; Wed, 24 Nov 2021 11:21:12 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org DD3623858412 From: "pinskia at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug c/103406] gcc -O0 behaves differently on "DBL_MAX related operations" than gcc -O1 and above Date: Wed, 24 Nov 2021 11:21:12 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: c X-Bugzilla-Version: 11.1.0 X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: pinskia at gcc dot gnu.org X-Bugzilla-Status: UNCONFIRMED X-Bugzilla-Resolution: X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-BeenThere: gcc-bugs@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-bugs mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 24 Nov 2021 11:21:13 -0000 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D103406 --- Comment #1 from Andrew Pinski --- This is interesting. The trunk does 0.0 for both -O0 and -O1. ICC also does 0.0 for both -O0 and -O1 and -0.0 for -O2. clang does -nan for -O1, -O2 and -O0 MSVC does nan for /O2 and /O1 (7ff8000000000000) and for the non-optimizing case (I think if I read the assembly correctly).=