From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id B3BFC3858405; Mon, 27 Sep 2021 10:16:13 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org B3BFC3858405 From: "jakub at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug c++/102490] Erroneous optimization of default constexpr operator== of struct with bitfields Date: Mon, 27 Sep 2021 10:16:13 +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: 10.1.0 X-Bugzilla-Keywords: wrong-code X-Bugzilla-Severity: normal X-Bugzilla-Who: jakub at gcc dot gnu.org X-Bugzilla-Status: NEW 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: everconfirmed cc cf_reconfirmed_on bug_status 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: Mon, 27 Sep 2021 10:16:13 -0000 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D102490 Jakub Jelinek changed: What |Removed |Added ---------------------------------------------------------------------------- Ever confirmed|0 |1 CC| |jakub at gcc dot gnu.org Last reconfirmed| |2021-09-27 Status|UNCONFIRMED |NEW --- Comment #1 from Jakub Jelinek --- Before r10-4397-gb7689b962dd6536bbb2567bfdec52e35109af7ab , this has been rejected with: pr102490.C:5:48: error: =E2=80=98constexpr bool A::operator=3D=3D(const A&)= const=E2=80=99 cannot be defaulted 5 | constexpr bool operator=3D=3D (const A&) const =3D default; | ^~~~~~~ pr102490.C:5:18: warning: inline function =E2=80=98constexpr bool A::operat= or=3D=3D(const A&) const=E2=80=99 used but never defined 5 | constexpr bool operator=3D=3D (const A&) const =3D default; | ^~~~~~~~ but since then it emits: pr102490.C: In member function =E2=80=98constexpr bool A::operator=3D=3D(co= nst A&) const=E2=80=99: pr102490.C:5:18: error: type mismatch in =E2=80=98component_ref=E2=80=99 5 | constexpr bool operator=3D=3D (const A&) const =3D default; | ^~~~~~~~ unsigned char _1 =3D this->foo; pr102490.C:5:18: error: type mismatch in =E2=80=98component_ref=E2=80=99 unsigned char _2 =3D D.2080->foo; pr102490.C:5:18: error: type mismatch in =E2=80=98component_ref=E2=80=99 unsigned char _3 =3D this->bar; pr102490.C:5:18: error: type mismatch in =E2=80=98component_ref=E2=80=99 unsigned char _4 =3D D.2080->bar; pr102490.C:5:18: internal compiler error: =E2=80=98verify_gimple=E2=80=99 f= ailed at -O0 or miscompiles it at -O1.=