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 94ADF385BF92; Wed,  1 Apr 2020 16:10:49 +0000 (GMT)
DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 94ADF385BF92
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org;
 s=default; t=1585757449;
 bh=Ljsk3FDK8K1vuwoAn3nXpmC0ByyKuebvSaltTkVZVt0=;
 h=From:To:Subject:Date:From;
 b=Vz1k2N1NOfyuWqM1Thigom26Io6ZrYm5+CFdaZlczeWGWDJURYWvezSmOOII8plbb
 pjq5OHQEWIlF8aGU9kpu010NOFJp2k3fgwAuYMz/TVDaSsO47hYFmHUbIvcO7vTCXj
 jz7cKBFHIyFsKQ4JCsSyp8iKHVruHucG95xqNV/g=
From: "dmalcolm at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug analyzer/94447] New: Not handling CONSTRUCTOR tree code
Date: Wed, 01 Apr 2020 16:10:49 +0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: new
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: analyzer
X-Bugzilla-Version: 10.0
X-Bugzilla-Keywords: 
X-Bugzilla-Severity: normal
X-Bugzilla-Who: dmalcolm at gcc dot gnu.org
X-Bugzilla-Status: UNCONFIRMED
X-Bugzilla-Resolution: 
X-Bugzilla-Priority: P3
X-Bugzilla-Assigned-To: dmalcolm 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: <bug-94447-4@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: <http://gcc.gnu.org/mailman/options/gcc-bugs>,
 <mailto:gcc-bugs-request@gcc.gnu.org?subject=unsubscribe>
List-Archive: <http://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: <http://gcc.gnu.org/mailman/listinfo/gcc-bugs>,
 <mailto:gcc-bugs-request@gcc.gnu.org?subject=subscribe>
X-List-Received-Date: Wed, 01 Apr 2020 16:10:49 -0000

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D94447

            Bug ID: 94447
           Summary: Not handling CONSTRUCTOR tree code
           Product: gcc
           Version: 10.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: analyzer
          Assignee: dmalcolm at gcc dot gnu.org
          Reporter: dmalcolm at gcc dot gnu.org
  Target Milestone: ---

Consider e.g.:

struct foo
{
  int *v;
};

int test (void)
{
  struct foo f =3D {};
  return *f.v;
}

This currently reports
t.c: In function =E2=80=98test=E2=80=99:
t.c:9:10: warning: use of uninitialized value =E2=80=98<unknown>=E2=80=99 [=
CWE-457]
[-Wanalyzer-use-of-uninitialized-value]
    9 |   return *f.v;
      |          ^~~~
  =E2=80=98test=E2=80=99: event 1
    |
    |

when it should be a NULL dereference.

The f =3D {}; shows up as f =3D {}; in the gimple dump, a CONSTRUCTOR, and
region_model::on_assignment is hitting a TODO for that tree code.=