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 BE7853858405; Mon,  8 Nov 2021 21:48:23 +0000 (GMT)
DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org BE7853858405
From: "msebor at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/103121] [12 Regression] Warnings in
 cp/optimize.c causing build failure
Date: Mon, 08 Nov 2021 21:48:23 +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: build, diagnostic
X-Bugzilla-Severity: normal
X-Bugzilla-Who: msebor at gcc dot gnu.org
X-Bugzilla-Status: NEW
X-Bugzilla-Resolution: 
X-Bugzilla-Priority: P3
X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org
X-Bugzilla-Target-Milestone: 12.0
X-Bugzilla-Flags: 
X-Bugzilla-Changed-Fields: 
Message-ID: <bug-103121-4-urhzjG4Elh@http.gcc.gnu.org/bugzilla/>
In-Reply-To: <bug-103121-4@http.gcc.gnu.org/bugzilla/>
References: <bug-103121-4@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: Mon, 08 Nov 2021 21:48:23 -0000

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D103121

--- Comment #12 from Martin Sebor <msebor at gcc dot gnu.org> ---
Okay, here's my question: when I call range_of_expr (vr, _4, stmt) with stmt
being 'grp_name_37 =3D __builtin_alloca (_4)' in BB 4, should I not expect =
the
result to be either VR_VARYING or [0, +INF]?

What I think is wrong is that the result is VR_RANGE [1, 1].  That is true =
in
BB 12 but I did not tell ranger that I'm asking about _4 for BB 12 (i.e., t=
he
4->12 edge).  I just asked it about _4 in BB 4.

The result for the BB 12 query actually happens to be cached by the
pointer_query class and retrieved for subsequent queries about pointers use=
d in
other BB's, but those queries are all independent of the path from BB 4 to =
the
BB they're being made for.  When I disable the caching then the first query
about _4 in BB 4 (made on behalf of BB 12) gives me [1, 1], and the query f=
or
_4 in BB 4 (made on behalf of BB 13) gives me VR_VARYING and the warning
disappears.  The latter is as expected but I don't expect to get a different
range for the same SSA_NAME in the same basic block unless I specify which
outgoing edge I'm interested in.

So what am I missing?=