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 2C8FA3950CB7; Tue,  3 Aug 2021 12:54:25 +0000 (GMT)
DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 2C8FA3950CB7
From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/101750] [12 regression]
 g++.dg/vect/pr99149.cc fails on aarch64 since r12-2523
Date: Tue, 03 Aug 2021 12:54:25 +0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: changed
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: tree-optimization
X-Bugzilla-Version: 12.0
X-Bugzilla-Keywords: wrong-code
X-Bugzilla-Severity: normal
X-Bugzilla-Who: rguenth at gcc dot gnu.org
X-Bugzilla-Status: NEW
X-Bugzilla-Resolution: 
X-Bugzilla-Priority: P1
X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org
X-Bugzilla-Target-Milestone: 12.0
X-Bugzilla-Flags: 
X-Bugzilla-Changed-Fields: keywords everconfirmed bug_status
 cf_reconfirmed_on cc priority
Message-ID: <bug-101750-4-ewSwT3P8RV@http.gcc.gnu.org/bugzilla/>
In-Reply-To: <bug-101750-4@http.gcc.gnu.org/bugzilla/>
References: <bug-101750-4@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: Tue, 03 Aug 2021 12:54:25 -0000

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D101750

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |wrong-code
     Ever confirmed|0                           |1
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2021-08-03
                 CC|                            |tnfchris at gcc dot gnu.org
           Priority|P3                          |P1

--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
On x86_64 the testcase is optimized to the following now:

int main ()
{
  float d$b;
  float l$c;
  float l$b;
  float k$c;
  float k$b;

  <bb 2> [local count: 1073741824]:
  k$b_4 =3D{v} MEM[(const struct a &)0B].b;
  __builtin_trap ();

}

not sure how we conclude that 'n' is not written to anywhere.  The issue
persists even when I rename 'main' to 'foo' (when it's 'main' we could inde=
ed
conclude so).=