From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gcc-bugs-return-497597-listarch-gcc-bugs=gcc.gnu.org@gcc.gnu.org>
Received: (qmail 50674 invoked by alias); 20 Sep 2015 06:16:07 -0000
Mailing-List: contact gcc-bugs-help@gcc.gnu.org; run by ezmlm
Precedence: bulk
List-Id: <gcc-bugs.gcc.gnu.org>
List-Archive: <http://gcc.gnu.org/ml/gcc-bugs/>
List-Post: <mailto:gcc-bugs@gcc.gnu.org>
List-Help: <mailto:gcc-bugs-help@gcc.gnu.org>
Sender: gcc-bugs-owner@gcc.gnu.org
Received: (qmail 50556 invoked by uid 48); 20 Sep 2015 06:15:57 -0000
From: "law at redhat dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/47679] [4.9/5/6 Regression] Strange uninitialized warning after SRA
Date: Sun, 20 Sep 2015 06:16:00 -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: 4.6.0
X-Bugzilla-Keywords: diagnostic
X-Bugzilla-Severity: normal
X-Bugzilla-Who: law at redhat dot com
X-Bugzilla-Status: NEW
X-Bugzilla-Resolution:
X-Bugzilla-Priority: P2
X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org
X-Bugzilla-Target-Milestone: 4.9.4
X-Bugzilla-Flags:
X-Bugzilla-Changed-Fields:
Message-ID: <bug-47679-4-jaD3qpVPZM@http.gcc.gnu.org/bugzilla/>
In-Reply-To: <bug-47679-4@http.gcc.gnu.org/bugzilla/>
References: <bug-47679-4@http.gcc.gnu.org/bugzilla/>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: 7bit
X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/
Auto-Submitted: auto-generated
MIME-Version: 1.0
X-SW-Source: 2015-09/txt/msg01575.txt.bz2

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=47679

--- Comment #30 from Jeffrey A. Law <law at redhat dot com> ---
AFACT the testcase in c#16 is bogus.  If i is never equal to k, then opt is
never assigned any value.  It's then used in the conditional outside the loop. 
That's how it looks at the source level and that's also what it looks like in
the dom2 dump.