From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id C8376385DDE5; Tue, 4 Jun 2024 21:03:55 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org C8376385DDE5 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1717535035; bh=kmVZoZRw8FluxDxhly8UClj/SX1btAKz0r4Nb8Qy2YI=; h=From:To:Subject:Date:In-Reply-To:References:From; b=kTFLPuKFWWjY1+0irpIKfyLMDI64cKQt2DU/4oSffieRO374QhLUhfkf/46s9c1CN aopNFX4VIHTP2G1N/IapfIc+BFPKelIv6Q56c/tGOeonHpYNSen0/KTvpHM4BL3rq0 w9FgC0rxqFLHSzUoV1/O8OP8KoANUUvWapGEEp8c= From: "aoliva at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug tree-optimization/115177] incorrect TBAA for derived types involving hardbool types Date: Tue, 04 Jun 2024 21:03:54 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: tree-optimization X-Bugzilla-Version: 15.0 X-Bugzilla-Keywords: alias, wrong-code X-Bugzilla-Severity: normal X-Bugzilla-Who: aoliva 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 List-Id: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D115177 --- Comment #4 from Alexandre Oliva --- One could argue either way. As a hardened type, discouraging aliasing that would bypass the hardening could also make sense. It was modeled after Ada, whose aliasing is much stricter, but I guess in C it is reasonable to make = it more C-like in C, and allow it to alias with the underlying integral type. = The feature request did not specify it either way, so I suspect reliable lax aliasing was not expected.=