From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id 756DC386F037; Thu, 14 Jan 2021 01:24:13 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 756DC386F037 From: "tedheadster at gmail dot com" To: gcc-bugs@gcc.gnu.org Subject: [Bug c++/98667] New: gcc generates endbr32 invalid opcode on -march=i486 Date: Thu, 14 Jan 2021 01:24:13 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: new X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: c++ X-Bugzilla-Version: 9.3.0 X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: tedheadster at gmail dot com 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: bug_id short_desc product version bug_status bug_severity priority component assigned_to reporter target_milestone Message-ID: 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: Thu, 14 Jan 2021 01:24:13 -0000 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D98667 Bug ID: 98667 Summary: gcc generates endbr32 invalid opcode on -march=3Di486 Product: gcc Version: 9.3.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ Assignee: unassigned at gcc dot gnu.org Reporter: tedheadster at gmail dot com Target Milestone: --- Compiling the 'eix' program with gcc 9.3.0 and the '-march=3Di486' generate= d an 'endbr32' opcode. This is an undefined opcode on an i486. # /usr/bin/gdb /usr/bin/eix GNU gdb (Gentoo 10.1 vanilla) 10.1 ... Reading symbols from /usr/bin/eix... Reading symbols from /usr/lib/debug//usr/bin/eix.debug... (gdb) run Starting program: /usr/bin/eix Program received signal SIGILL, Illegal instruction. _GLOBAL__sub_I_spaces () at eixTk/stringutils.cc:686 686 =C2=A0 =C2=A0 } (gdb) disassemble _GLOBAL__sub_I_spaces Dump of assembler code for function _GLOBAL__sub_I_spaces(): =3D> 0x004208e0 <+0>: =C2=A0 =C2=A0 endbr32 =C2=A0 =C2=A00x004208e4 <+4>: =C2=A0 =C2=A0 push =C2=A0 %esi =C2=A0 =C2=A00x004208e5 <+5>: =C2=A0 =C2=A0 push =C2=A0 %ebx =C2=A0 =C2=A00x004208e6 <+6>: =C2=A0 =C2=A0 sub =C2=A0 =C2=A0$0xc,%esp =C2=A0 =C2=A00x004208e9 <+9>: =C2=A0 =C2=A0 call =C2=A0 0x420d30 <__x86.get= _pc_thunk.bx> =C2=A0 =C2=A00x004208ee <+14>: =C2=A0 =C2=A0add =C2=A0 =C2=A0$0x17e712,%ebx =C2=A0 =C2=A00x0042091e <+62>: =C2=A0 =C2=A0add =C2=A0 =C2=A0$0x14,%esp =C2=A0 =C2=A00x00420921 <+65>: =C2=A0 =C2=A0pop =C2=A0 =C2=A0%ebx =C2=A0 =C2=A00x00420922 <+66>: =C2=A0 =C2=A0pop =C2=A0 =C2=A0%esi =C2=A0 =C2=A00x00420923 <+67>: =C2=A0 =C2=A0ret =C2=A0 =C2=A0 (gdb) list 681 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 i= f(likely(isutf8firstgyte(t[i]))) { 682 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 = =C2=A0 =C2=A0 =C2=A0 =C2=A0 ++len; 683 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 } 684 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 } 685 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 return len; 686 =C2=A0 =C2=A0 }=