From owner-freebsd-current@FreeBSD.ORG Thu Jan 6 08:01:11 2011 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 5B9E8106566C; Thu, 6 Jan 2011 08:01:11 +0000 (UTC) (envelope-from erik@cederstrand.dk) Received: from csmtp3.one.com (csmtp3.one.com [91.198.169.23]) by mx1.freebsd.org (Postfix) with ESMTP id E4BCF8FC1B; Thu, 6 Jan 2011 08:01:10 +0000 (UTC) Received: from macfeast.lan (0x573b9942.cpe.ge-1-2-0-1101.ronqu1.customer.tele.dk [87.59.153.66]) by csmtp3.one.com (Postfix) with ESMTP id 5CBE2240639E; Thu, 6 Jan 2011 08:01:08 +0000 (UTC) Mime-Version: 1.0 (Apple Message framework v1082) Content-Type: multipart/signed; boundary=Apple-Mail-140-313573145; protocol="application/pkcs7-signature"; micalg=sha1 From: Erik Cederstrand In-Reply-To: <20110105193653.GA49285@stack.nl> Date: Thu, 6 Jan 2011 09:01:09 +0100 Message-Id: <7FA66A47-CB15-4C22-8614-B58E986CFFA4@cederstrand.dk> References: <20110105131439.GN23329@acme.spoerlein.net> <4184C8F2-3C6D-46FB-8F10-DDEBA6DB1C35@cederstrand.dk> <201101050934.49845.jhb@freebsd.org> <20110105165545.GP23329@acme.spoerlein.net> <20110105193653.GA49285@stack.nl> To: Jilles Tjoelker X-Mailer: Apple Mail (2.1082) X-Content-Filtered-By: Mailman/MimeDel 2.1.5 Cc: freebsd-current@freebsd.org Subject: Re: FYI: clang static analyzer page has moved to http://scan.freebsd.your.org/freebsd-head/ X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 06 Jan 2011 08:01:11 -0000 --Apple-Mail-140-313573145 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=iso-8859-1 Den 05/01/2011 kl. 20.36 skrev Jilles Tjoelker: > On Wed, Jan 05, 2011 at 05:55:45PM +0100, Ulrich Sp=F6rlein wrote: >> On Wed, 05.01.2011 at 09:34:49 -0500, John Baldwin wrote: >>> These are all marked as __dead2, so the compiler should "know" that = these do >>> not return. >=20 >> And clang did the right thing here in the past. Beware that it does = no >> inter-procedural analysis yet, so it will usually miss that usage() >> calls exit unconditionally. >=20 >> *But*, it should grok that for err(3) and exit(3). Now there are some >> possible remedies: >=20 >> - get IPA to work with clang, or at least file a bug >=20 >> - mark functions as __dead2 (please don't do that) >=20 > Why not? Because the analyzer is supposed to find bugs. Only the function that = really doesn't return should be marked as such. If we begin spewing = __dead2's everywhere, it's bound to silence a valid bug somewhere down = the line when e.g. a conditional in a print_help() function is changed = subtly so it doesn't always reach exit(). Erik= --Apple-Mail-140-313573145--