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 383A63858C62; Mon, 20 Mar 2023 20:20:31 +0000 (GMT)
DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 383A63858C62
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org;
	s=default; t=1679343631;
	bh=sbuQ775huGUIg7o6y8agovOgpSmmjv2w4gRi4tyOVi0=;
	h=From:To:Subject:Date:In-Reply-To:References:From;
	b=O3Jabl2WMGRnQNv2CCCWD6p02K7ko5JD8wKt0q1RosGleWIp1dI2rL6vDXPJe900T
	 bBDLaJzPtEHiJXfK838v7F7xh6IB7ZVycff1p7ScsOYXcUqKkzSfEnwR0dN1GWOvJs
	 qC2TgZurTzJ4oedfLPsYx3zd+L3+6tS2ZhCcPXaA=
From: "dmalcolm at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug analyzer/109191] GCC static analyzer does not warning `*b = 1`
 where `b` is 1.
Date: Mon, 20 Mar 2023 20:20:30 +0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: changed
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: analyzer
X-Bugzilla-Version: 13.0
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: 
Message-ID: <bug-109191-4-DdYVMnlATh@http.gcc.gnu.org/bugzilla/>
In-Reply-To: <bug-109191-4@http.gcc.gnu.org/bugzilla/>
References: <bug-109191-4@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
List-Id: <gcc-bugs.sourceware.org>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D109191

--- Comment #1 from David Malcolm <dmalcolm at gcc dot gnu.org> ---
GCC does emit a -Wint-to-pointer-cast warning on this code, for the int to =
void
* conversion.

Is this reduced from a real-world example, or just synthesized by hand?

I suppose in theory the analyzer could:

(a) figure out that it reads all zeroes from the array and complain about t=
he
null pointer deref, and/or

(b) complain that we're accessing beyond the end of an array=