From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id E53D13952005; Wed, 16 Mar 2022 23:10:47 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org E53D13952005 From: "jwerner at chromium dot org" To: gcc-bugs@gcc.gnu.org Subject: [Bug middle-end/99578] [11/12 Regression] gcc-11 -Warray-bounds or -Wstringop-overread warning when accessing a pointer from integer literal Date: Wed, 16 Mar 2022 23:10:47 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: middle-end X-Bugzilla-Version: 11.0 X-Bugzilla-Keywords: diagnostic X-Bugzilla-Severity: normal X-Bugzilla-Who: jwerner at chromium dot org X-Bugzilla-Status: NEW X-Bugzilla-Resolution: X-Bugzilla-Priority: P2 X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org X-Bugzilla-Target-Milestone: 11.3 X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: cc 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, 16 Mar 2022 23:10:48 -0000 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D99578 Julius Werner changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |jwerner at chromium dot org --- Comment #32 from Julius Werner --- I second Kees' request to please (permanently) add a flag to disable this inference and prevent GCC from making any assumptions about object sizes for pointers cast from integers. Ideally it should be a separate one-off flag rather than a level that needs to be set for a variety of individual warnin= gs. This is affecting almost every systems programming project there is and goi= ng against 40 years of common C practice. The standard has never really specif= ied a way to do MMIO hardware accesses, yet it's something we need to do in practice and casting integer literals to pointers is one of the main ways w= e do it. I don't think it's reasonable to suddenly start in 2022 to prosecute a "violation" that has been this prevalent for decades in programming practic= e. If you want to make these new safety checks available for those who want th= em that's fine, but please retain the option to stick with the existing behavi= or for those projects where this really causes a ton more problems than it cou= ld ever solve.=