From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 20655 invoked by alias); 18 Feb 2011 15:24:58 -0000 Received: (qmail 20645 invoked by uid 22791); 18 Feb 2011 15:24:57 -0000 X-SWARE-Spam-Status: No, hits=-1.9 required=5.0 tests=AWL,BAYES_00,T_RP_MATCHES_RCVD X-Spam-Check-By: sourceware.org Received: from mail.codesourcery.com (HELO mail.codesourcery.com) (38.113.113.100) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Fri, 18 Feb 2011 15:24:52 +0000 Received: (qmail 20364 invoked from network); 18 Feb 2011 15:24:51 -0000 Received: from unknown (HELO scottsdale.localnet) (pedro@127.0.0.2) by mail.codesourcery.com with ESMTPA; 18 Feb 2011 15:24:51 -0000 From: Pedro Alves To: "Pierre Muller" Subject: Re: [RFA] Fix display of array of unspecified length inside structures Date: Fri, 18 Feb 2011 15:38:00 -0000 User-Agent: KMail/1.13.5 (Linux/2.6.35-25-generic; KDE/4.6.0; x86_64; ; ) Cc: gdb-patches@sourceware.org References: <00ac01cbcf5c$31f5bc00$95e13400$@muller@ics-cnrs.unistra.fr> <201102181147.52337.pedro@codesourcery.com> <00c301cbcf7b$afaa6d20$0eff4760$@muller@ics-cnrs.unistra.fr> In-Reply-To: <00c301cbcf7b$afaa6d20$0eff4760$@muller@ics-cnrs.unistra.fr> MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <201102181524.45999.pedro@codesourcery.com> X-IsSubscribed: yes Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org X-SW-Source: 2011-02/txt/msg00464.txt.bz2 On Friday 18 February 2011 14:54:03, Pierre Muller wrote: > > On Friday 18 February 2011 11:08:38, Pierre Muller wrote: > > > > > PS: It could be wise to add some test in the testsuite for > > > this, but I have no idea where I could insert this kind of test, > > > any ideas? > > > > Yes, please. We have surprisingly few tests for this sort of > > thing, AFAICS. I'm not even sure this is a regression from > > my recent changes, I think it may well not be. > > I checked out gdb version 7.2 shows this regression, > as compared to Cygwin 6.8 at least... > Which means that the regression is not really recent. > > This might means that we should also merge this patch to > the branch, no? Sound fine to me. > > > Zero-length arrays (as poor man's flexible arrays) are supported > > in GNU C as an extension. To be portable, you'd > > need to use an array of length 1 (or c99's real flexible arrays), > > but that won't trigger the bug. > Apparently there is also the flexible array member construct > see > http://gcc.gnu.org/onlinedocs/gcc-4.1.2/gcc/Zero-Length.html That just confirms what I said. :-) The flexible array member construst is C99 only, so it's likely that other compilers choke on it by default. > > I'd point at printcmds.exp, but I'm not sure if there are compilers > > out there that choke on the construct... There's always a > > new test file option... > > > > > PS2: It is probably impossible to make such a test without > > > alloca or some other memory allocation function, no? > > > Are there any system restriction for this? > > There is a long check at start of gdb.base/funcargs.c > but it might just be to really check that alloca really uses > the stack... Irk. Just use malloc then? It's not really crutial that the test runs on all targets/hosts. As long as it runs on the targets must people are developing on (GNU/Linux,Windows), it's fine, we're reasonably well covered. -- Pedro Alves