From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 127928 invoked by alias); 18 Jul 2018 19:53:12 -0000 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 Received: (qmail 127909 invoked by uid 89); 18 Jul 2018 19:53:11 -0000 Authentication-Results: sourceware.org; auth=none X-Spam-SWARE-Status: No, score=-2.4 required=5.0 tests=AWL,BAYES_00,SPF_HELO_PASS,SPF_PASS autolearn=ham version=3.3.2 spammy=gdb-test, gdbtest X-HELO: smtp.polymtl.ca Received: from smtp.polymtl.ca (HELO smtp.polymtl.ca) (132.207.4.11) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Wed, 18 Jul 2018 19:53:10 +0000 Received: from simark.ca (simark.ca [158.69.221.121]) (authenticated bits=0) by smtp.polymtl.ca (8.14.7/8.14.7) with ESMTP id w6IJr3XR025252 (version=TLSv1/SSLv3 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT) for ; Wed, 18 Jul 2018 15:53:07 -0400 Received: by simark.ca (Postfix, from userid 112) id 0F7341EF28; Wed, 18 Jul 2018 15:53:03 -0400 (EDT) Received: from simark.ca (localhost [127.0.0.1]) by simark.ca (Postfix) with ESMTP id B9B821E08D; Wed, 18 Jul 2018 15:53:01 -0400 (EDT) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Wed, 18 Jul 2018 19:53:00 -0000 From: Simon Marchi To: Tom de Vries Cc: gdb-patches@sourceware.org Subject: Re: [PATCH][gdb/exp] Fix printing of type of optimized out vla In-Reply-To: <20180703141821.wzcayjt4ykepdotg@delia> References: <20180703141821.wzcayjt4ykepdotg@delia> Message-ID: X-Sender: simon.marchi@polymtl.ca User-Agent: Roundcube Webmail/1.3.6 X-IsSubscribed: yes X-SW-Source: 2018-07/txt/msg00566.txt.bz2 On 2018-07-03 10:18, Tom de Vries wrote: > Hi, > > Consider this snippet from gcc/testsuite/gcc.dg/guality/vla-1.c: > ... > int __attribute__((noinline)) > f1 (int i) > { > char a[i + 1]; > a[0] = 5; /* { dg-final { gdb-test .+1 "i" "5" } } */ > return a[0]; /* { dg-final { gdb-test . "sizeof (a)" "6" } } > */ > } > ... > > When we compile the test-case with -O1 -g, and query the size of > optimized > out vla 'a', we get: > ... > $ ./gdb -batch -ex "b f1" -ex "r" -ex "p sizeof (a)" vla-1.exe > Breakpoint 1 at 0x4004a8: file vla-1.c, line 17. > > Breakpoint 1, f1 (i=i@entry=5) at vla-1.c:17 > 17 return a[0]; > $1 = 0 > ... > while we expect a size of '6'. > > The problem is that default_read_var_value does not resolve the dynamic > type > of a variable if the variable is optimized out. > > This patch fixes that, and consequently gdb prints '6', as expected. > > Tested on x86_64-linux. > > OK for trunk? > > Thanks, > - Tom Thanks, that LGTM. Simon