From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gcc-bugzilla@gcc.gnu.org>
Received: by sourceware.org (Postfix, from userid 48)
 id 76F793839C66; Sat,  1 May 2021 12:47:43 +0000 (GMT)
DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 76F793839C66
From: "iains at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug bootstrap/100373] New: [12 Regression] Darwin, Compare-debug
 fail after r12-248-gb58dc0b803057
Date: Sat, 01 May 2021 12:47:43 +0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: new
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: bootstrap
X-Bugzilla-Version: unknown
X-Bugzilla-Keywords: 
X-Bugzilla-Severity: normal
X-Bugzilla-Who: iains 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: bug_id short_desc product version bug_status
 bug_severity priority component assigned_to reporter target_milestone
 attachments.created
Message-ID: <bug-100373-4@http.gcc.gnu.org/bugzilla/>
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 <gcc-bugs.gcc.gnu.org>
List-Unsubscribe: <https://gcc.gnu.org/mailman/options/gcc-bugs>,
 <mailto:gcc-bugs-request@gcc.gnu.org?subject=unsubscribe>
List-Archive: <https://gcc.gnu.org/pipermail/gcc-bugs/>
List-Post: <mailto:gcc-bugs@gcc.gnu.org>
List-Help: <mailto:gcc-bugs-request@gcc.gnu.org?subject=help>
List-Subscribe: <https://gcc.gnu.org/mailman/listinfo/gcc-bugs>,
 <mailto:gcc-bugs-request@gcc.gnu.org?subject=subscribe>
X-List-Received-Date: Sat, 01 May 2021 12:47:43 -0000

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D100373

            Bug ID: 100373
           Summary: [12 Regression] Darwin, Compare-debug fail after
                    r12-248-gb58dc0b803057
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: bootstrap
          Assignee: unassigned at gcc dot gnu.org
          Reporter: iains at gcc dot gnu.org
  Target Milestone: ---

Created attachment 50725
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=3D50725&action=3Dedit
tarball with asm, objects and obj dumps.

Exactly which cases fail seems to depend on the CPU in use and the OS versi=
on.=20
For modern CPUs (xeon w, core i5 Skylake) the fail seems to be quite reliab=
ly
in mpfr (which I build in tree).  For older corei7 machines on Darwin16, I'=
ve
seen also gcc/gcc.o as mismatched.

I did a run with -save-temps -dp (asm attached).
this is on x86_64-darwin20, but the problem is seen on x86_64-darwin* AFAIC=
T.=20
Backing out r12-248-gb58dc0b803057 allows bootstrap to succeed.

attached:

stage2-mpfr/src/gmp_op.o.stripped
stage2-mpfr/src/gmp_op.o
stage2-mpfr/src/gmp_op.s
s2.txt =3D=3D objdump -d -r stage2-mpfr/src/gmp_op.o.stripped >s2.txt
stage3-mpfr/src/gmp_op.o.stripped
stage3-mpfr/src/gmp_op.o
stage3-mpfr/src/gmp_op.s
s3.txt =3D=3D objdump -d -r stage3-mpfr/src/gmp_op.o.stripped >s3.txt=