From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from simark.ca by simark.ca with LMTP id vTqSOtmimGecBx0AWB0awg (envelope-from ) for ; Tue, 28 Jan 2025 04:26:49 -0500 Authentication-Results: simark.ca; dkim=pass (1024-bit key; secure) header.d=sourceware.org header.i=@sourceware.org header.a=rsa-sha256 header.s=default header.b=tY8J4Mbq; dkim-atps=neutral Received: by simark.ca (Postfix, from userid 112) id DE3C71E105; Tue, 28 Jan 2025 04:26:49 -0500 (EST) X-Spam-Checker-Version: SpamAssassin 4.0.0 (2022-12-13) on simark.ca X-Spam-Level: X-Spam-Status: No, score=-5.4 required=5.0 tests=ARC_SIGNED,ARC_VALID,BAYES_00, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED autolearn=ham autolearn_force=no version=4.0.0 Received: from server2.sourceware.org (server2.sourceware.org [8.43.85.97]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by simark.ca (Postfix) with ESMTPS id 5633D1E08E for ; Tue, 28 Jan 2025 04:26:48 -0500 (EST) Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id 993453858031 for ; Tue, 28 Jan 2025 09:26:47 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 993453858031 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1738056407; bh=vDo2Vh5EDfhCHykb1DJSiYSycRmvLZXn1YC7Y5lJdDs=; h=Date:Subject:To:References:In-Reply-To:List-Id:List-Unsubscribe: List-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To: From; b=tY8J4MbqAEywiL0KvKbMnli+WYqmQvHXYej6t9Wds+cpjhMDZJwa47g47+/9B4QY6 7HjAZxe8qgHwt9JgKpfUfl5cvE8I4/lvJ14LJVlDhFIqqNh8oXgW7DMDnnvPNKL6Da 4QZWDNfkbMhNL6ElSVqItrLp2+xLC9hxUz9R0gQo= Received: from holomatrix.labath.sk (holomatrix.labath.sk [92.48.105.150]) by sourceware.org (Postfix) with ESMTPS id 8403D385843B for ; Tue, 28 Jan 2025 09:25:56 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 8403D385843B ARC-Filter: OpenARC Filter v1.0.0 sourceware.org 8403D385843B ARC-Seal: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1738056356; cv=none; b=BLn+Fx1xoaLOAhFNuoZOkyI6V78WLdBS6PCtDxGKHLwHK/5BIVrIKX9W3b7ugrrFM83vL049zKAoR1YH/P6jm5Vg7r6zIpd+/dIUKOSlDhltc8C3Cvtxj/Q2jAJWg7vDvtGeL+DT3W+yfCad65KnriBHT5ymNppkPqi56OPR1NU= ARC-Message-Signature: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1738056356; c=relaxed/simple; bh=cdc19Ct6Fh6h5jlbgZpSHvw2NyvKQAgUYakZsdxRs2g=; h=DKIM-Signature:Message-ID:Date:MIME-Version:Subject:To:From; b=OrIRMtPk/9Nf8OCURAMlsgaocKLfUuZ2PpP4btf71P4rpvKa2TZDK3LhXYNSIuOnOCL6MWEqTmwglXdB7XHZii564XcwDhMxNfO7hnWXGL+GpBtalkCyDSoQR3kg4/toXLu89aNf0hl5ven52Dsrg9pDLX8WU6aap1gqeDW39Ro= ARC-Authentication-Results: i=1; server2.sourceware.org DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 8403D385843B Received: from [172.21.6.108] (nat-vidiek.mag-net.sk [195.168.209.2]) by holomatrix.labath.sk (Postfix) with ESMTPSA id 1E6614147C; Tue, 28 Jan 2025 10:25:55 +0100 (CET) Message-ID: <28fba5b6-e6b7-4a3c-b6a3-10b46c087910@labath.sk> Date: Tue, 28 Jan 2025 10:25:54 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: Incompatible implementat ion of 'x' packet in GDB vs LLDB To: gdb@sourceware.org References: <87a5bhmrre.fsf@redhat.com> <877c6lmobo.fsf@redhat.com> <874j1pmib7.fsf@redhat.com> <174eaf99-737b-4b2a-a2a0-49282748cb62@labath.sk> Content-Language: en-GB In-Reply-To: <174eaf99-737b-4b2a-a2a0-49282748cb62@labath.sk> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-BeenThere: gdb@sourceware.org X-Mailman-Version: 2.1.30 Precedence: list List-Id: Gdb mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: Pavel Labath via Gdb Reply-To: Pavel Labath Errors-To: gdb-bounces~public-inbox=simark.ca@sourceware.org Sender: "Gdb" On 28/01/2025 09:26, Pavel Labath via Gdb wrote: > Hello everyone, an lldb dev here :) > > I'm sorry for the trouble our implementation of 'x' has caused. I have > to admit I was surprised to find that the packet was not in the gdb > documentation already. It's been implemented in lldb for as long as I > can remember (~10 years), and the new packets we're adding nowadays have > much longer names, so I had assumed that it was always a part of the gdb > spec. > > For what it's worth, I think your definition of the packet makes much > more sense. LLDB's definition is indeed ambiguous (and I didn't realize > how ambiguous until now) -- it cannot distinguish between a (truncated?) > memory read and an error. This behavior is not completely easy to > trigger because lldb will by default round the memory reads to 512-byte > boundaries (so truncation is unlikely), but with the right commands, I > was able to get it to treat valid memory as an error. > > For this reason, I am going to propose to migrate lldb to the gdb > ("official") definition of the packet. Since we have users which need > (fairly long) windows of compatibility with old server, this is going to > require method to detect the implementation in use, so I'd like to reuse > the same mechanism that's going to be used in gdb (both the zero length > probe and the qSupported method seem fine to me). > > regards, > Pavel And this is the lldb thread for that. pl