From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id ADF5C3858421; Wed, 3 Jan 2024 11:19:02 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org ADF5C3858421 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1704280742; bh=v2SBWDGWGGkbHv4J4SwCxZNFD9K6CR/T4ARVqZdg2K0=; h=From:To:Subject:Date:In-Reply-To:References:From; b=UiGz+77guFEzJh66CIvLS0vnXI6pFN8H8N1HD1aPtFnU4cnU43AzdUJWR5U2DB5r6 W/C1F9Mp6jWllqJCIybxpG0peZobAaGBEg9NUe21Ac7RoY8p3kcpVZV5f9Bjni+QHu Wbf5YSPXJ4CpGnLkt8ekgG8mTc6zcwXyfzUsSf2s= From: "redi at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug libstdc++/113202] std::find does not work with the maximum range of pointers Date: Wed, 03 Jan 2024 11:19:00 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: libstdc++ X-Bugzilla-Version: 13.2.0 X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: redi at gcc dot gnu.org X-Bugzilla-Status: RESOLVED X-Bugzilla-Resolution: INVALID 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=3D113202 --- Comment #11 from Jonathan Wakely --- s + OFFSET has undefined behaviour. With -O2 or -O3 GCC even tells you where the problem is: find_bug.cpp: In function 'int main(int, char**)': find_bug.cpp:39:61: warning: array subscript 1048576 is outside array bound= s of 'const char [6]' [-Warray-bounds=3D] 39 | std::cout << "strlen =3D " << strlen_no_ranges(s, s + OFFSET) << = ", no ranges, OFFSET =3D " << OFFSET << std::endl; | ^ find_bug.cpp:40:58: warning: array subscript 1048576 is outside array bound= s of 'const char [6]' [-Warray-bounds=3D] 40 | std::cout << "strlen =3D " << strlen_ranges(s, s + OFFSET) << = ", ranges, OFFSET =3D " << OFFSET << std::endl; |=