From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 11258 invoked by alias); 18 May 2012 15:28:08 -0000 Received: (qmail 11248 invoked by uid 22791); 18 May 2012 15:28:06 -0000 X-SWARE-Spam-Status: No, hits=-2.7 required=5.0 tests=AWL,BAYES_00,KHOP_THREADED X-Spam-Check-By: sourceware.org Received: from hagrid.ecoscentric.com (HELO mail.ecoscentric.com) (212.13.207.197) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Fri, 18 May 2012 15:27:52 +0000 Received: from localhost (hagrid.ecoscentric.com [127.0.0.1]) by mail.ecoscentric.com (Postfix) with ESMTP id 078672F7800A for ; Fri, 18 May 2012 16:27:51 +0100 (BST) Received: from mail.ecoscentric.com ([127.0.0.1]) by localhost (hagrid.ecoscentric.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id q7w2jht37GRx; Fri, 18 May 2012 16:27:49 +0100 (BST) From: bugzilla-daemon@bugs.ecos.sourceware.org To: ecos-patches@ecos.sourceware.org Subject: [Bug 1001344] Allow nc_test_slave for lwIP to compile for targets with 128KiB RAM. X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: eCos X-Bugzilla-Component: Patches and contributions X-Bugzilla-Keywords: X-Bugzilla-Severity: enhancement X-Bugzilla-Who: jifl@ecoscentric.com X-Bugzilla-Status: NEW X-Bugzilla-Priority: low X-Bugzilla-Assigned-To: unassigned@bugs.ecos.sourceware.org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Changed-Fields: In-Reply-To: References: X-Bugzilla-URL: http://bugs.ecos.sourceware.org/ Auto-Submitted: auto-generated Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Date: Fri, 18 May 2012 15:28:00 -0000 Message-Id: <20120518152749.70C9C2F78006@mail.ecoscentric.com> Mailing-List: contact ecos-patches-help@ecos.sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Post: List-Help: , Sender: ecos-patches-owner@ecos.sourceware.org X-SW-Source: 2012-05/txt/msg00062.txt.bz2 Please do not reply to this email. Use the web interface provided at: http://bugs.ecos.sourceware.org/show_bug.cgi?id=3D1001344 --- Comment #29 from Jonathan Larmour 2012-05-18 16:= 27:46 BST --- (In reply to comment #28) >=20 > > I think that "volatile" is strong enough so compiler wouldn't dare to d= rop > > it even for an automatic variable. I know that isn't always true. For example, if you call do_some_random_computation with a constant, gcc will optimise away the calculation. And with some code, gcc may be able to optimise expressions in= to constants that you may not expect it to be able to - it doesn't have to be a literal constant, but an expression gcc has worked out can only have one va= lue. For the case of nc_test_slave.c it does appear to be fine for that particul= ar case - it's not called with a constant. But my point is that your statement= is not generally true that volatile is guaranteed to be respected. And if it i= sn't generally true, what guarantee do we have that it will remain true in the c= ase of nc_test_slave.c's use of it as well. Anyway... > > I wonder if you can use both USED and UNUSED at the same time. Given th= eir > > intended functions, you should be able to, despite the English meanings > > implying they are in some way opposites to each other. That would deal = with the > > uncertainty. >=20 > Then we get ...warning: =E2=80=98used=E2=80=99 attribute ignored... as pe= r Comment #26. In that case we'll have to trust the GCC people will indeed continue to res= pect the volatile because we don't seem to have any alternative. Jifl --=20 Configure bugmail: http://bugs.ecos.sourceware.org/userprefs.cgi?tab=3Demail ------- You are receiving this mail because: ------- You are on the CC list for the bug.