From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 7237 invoked by alias); 28 Feb 2020 14:08:06 -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 7225 invoked by uid 89); 28 Feb 2020 14:08:05 -0000 Authentication-Results: sourceware.org; auth=none X-Spam-SWARE-Status: No, score=1.1 required=5.0 tests=BAYES_00,FREEMAIL_FROM,FSL_HELO_FAKE,RCVD_IN_DNSWL_NONE,SPF_PASS autolearn=no version=3.3.1 spammy=H*MI:sk:5171842, H*f:sk:5171842, H*i:sk:5171842 X-HELO: mail-wr1-f68.google.com Received: from mail-wr1-f68.google.com (HELO mail-wr1-f68.google.com) (209.85.221.68) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Fri, 28 Feb 2020 14:08:03 +0000 Received: by mail-wr1-f68.google.com with SMTP id e10so1646534wrr.10 for ; Fri, 28 Feb 2020 06:08:03 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=K1pkMYNmKUZ5324K/9+HKDjTdx0r3lFX6diQ4m9g+Jo=; b=bXYjN3T4ETbJMJ1/RDS3ANnGVuv1vbUP0VLTO0oqxeN7wKivihcjfFCSChyKris4f/ nZVLHrN6S3WmauqZ17aRTV/cHUq7NqUqj3f6n66HFagwAj23JGiyfAsfzDAgXdv0i5AB 3w2zZx5eWmRBNMdpw7qDXUo7q0IyQ1DZeSaIHNAFpHdSfJ6IkTghZbs8k9HavrsPELiW 3ZtlJmcqhQG/eFV8wDk4JAWXry1nAQhO3CGNXyEncsOl2fL8CfioLNAvDxp4oD4aVq6n Cq2WGqs1enu588N5LHfeOLNOl+W0pt4HOObcezGJ3DjJTM2ZUG2oWg8D+MhPFZr2b+Tz XYkQ== Return-Path: Received: from gmail.com ([2a03:1b20:3:f011::6d]) by smtp.gmail.com with ESMTPSA id m125sm2342620wmf.8.2020.02.28.06.07.59 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Fri, 28 Feb 2020 06:08:00 -0800 (PST) Date: Fri, 28 Feb 2020 14:08:00 -0000 From: Shahab Vahedi To: Luis Machado Cc: Christian Biesinger , Shahab Vahedi , "gdb-patches@sourceware.org" , Claudiu Zissulescu , Francois Bedard , Andrew Burgess Subject: Re: [Regression] [PATCH] Do not print empty-group regs when printing general ones Message-ID: <20200228140801.GB3269@gmail.com> References: <20200120155315.30333-1-shahab.vahedi@gmail.com> <75f76108-a233-6fce-66a2-86452371e1be@linaro.org> <9c256b27-4a00-8830-46e2-934922e39cc2@linaro.org> <20200228133618.GA3269@gmail.com> <51718427-72e2-ce12-7181-26ec9b38d947@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <51718427-72e2-ce12-7181-26ec9b38d947@linaro.org> X-SW-Source: 2020-02/txt/msg01046.txt.bz2 On Fri, Feb 28, 2020 at 10:50:54AM -0300, Luis Machado wrote: > On 2/28/20 10:36 AM, Shahab Vahedi wrote: > > On Fri, Feb 28, 2020 at 10:31:26AM -0300, Luis Machado wrote: > > > > > > > > > On 2/28/20 10:22 AM, Christian Biesinger wrote: > > > > On Fri, Feb 28, 2020 at 7:08 AM Luis Machado wrote: > > > > > > > > > > On 1/31/20 7:34 AM, Shahab Vahedi wrote: > > > > > > This patch was reviewed once (as OK): > > > > > > https://sourceware.org/ml/gdb-patches/2020-01/msg00613.html > > > > > > > > > > > > Could someone review/merge it? > > > > > > > > > > > > > > > > > > Cheers, > > > > > > Shahab > > > > > > > > > > > > > > > > FTR, this has broken general register printing for ARM/AArch64. Now > > > > > "info reg" shows nothing. > > > > > > > > > > Given there are already remote stubs, probes and gdbservers running out > > > > > there, this is an undesirable change to have. > > > > > > > > > > I had an IRC chat with Christian and he pointed me at some documentation > > > > > stating empty-group registers should not be printed, but i think this is > > > > > a case where the implementation has diverged from the documentation. > > > > > > > > > > https://sourceware.org/gdb/current/onlinedocs/gdb/Target-Description-Format.html#Target-Description-Format > > > > > > > > > > We could probably patch up any non-standard target description XML's > > > > > from now on, but the existing behavior may have to be preserved. > > > > > > > > Most targets under features/ do not specify group="general" in their > > > > XML files for anything (only S/390 does); it seems like that should > > > > maybe be fixed either way? > > > > > > I agree. > > > > The documentation [1] says: > > If no group is specified, GDB will not display the register in info registers > > > > [1] > > https://sourceware.org/gdb/onlinedocs/gdb/Target-Description-Format.html#Target-Description-Format > > > > That's valid, but unfortunately it doesn't change the fact the existing code > is breaking backwards compatibility with the installed base. > > As we discussed on IRC, this is code put together in early 2007 and hasn't > been touched since, apart from a small change in 2017 to cope with arbitrary > group strings. Plus we have plenty of existing target descriptions that do > not honor explicitly setting a register group. > > With that said, i think the documentation would have a lower priority in > this regard. We should fix the existing target descriptions to be more > strict with the group names, but the old behavior would have to be honored > IMO. I agree. The point in the patch was to make extra registers go away. However, it apparently eliminated the output of "info registers" for other targets and that is not OK. No matter sticking to the documentation or not. Feel free to revert the patch. Ideally I'd like a solution that: 1) "info registers": must not print the non-default (non-general) registers as it was the case with c9c895b9666 2) "info registers": should only print "general" group registers. This requires adding 'group="general"' to every XML features out there. So I don't know how realistic it is. Cheers, Shahab