From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gproxy4-pub.mail.unifiedlayer.com (gproxy4-pub.mail.unifiedlayer.com [69.89.23.142]) by sourceware.org (Postfix) with ESMTPS id 17C6F3858C50 for ; Thu, 9 Feb 2023 03:35:39 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 17C6F3858C50 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=tromey.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=tromey.com Received: from cmgw13.mail.unifiedlayer.com (unknown [10.0.90.128]) by progateway6.mail.pro1.eigbox.com (Postfix) with ESMTP id 8BA7E100483B8 for ; Thu, 9 Feb 2023 03:35:38 +0000 (UTC) Received: from box5379.bluehost.com ([162.241.216.53]) by cmsmtp with ESMTP id Pxikp6XFGNX2aPxikprcf2; Thu, 09 Feb 2023 03:35:38 +0000 X-Authority-Reason: nr=8 X-Authority-Analysis: v=2.4 cv=NMAQR22g c=1 sm=1 tr=0 ts=63e46a0a a=ApxJNpeYhEAb1aAlGBBbmA==:117 a=ApxJNpeYhEAb1aAlGBBbmA==:17 a=dLZJa+xiwSxG16/P+YVxDGlgEgI=:19 a=m04uMKEZRckA:10:nop_rcvd_month_year a=Qbun_eYptAEA:10:endurance_base64_authed_username_1 a=dzWzf_mpAAAA:8 a=vzq7gnAIF4iT9mQ21OEA:9 a=b4DR9a7p2ZdsqdHBznES:22 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=tromey.com; s=default; h=Content-Type:MIME-Version:Message-ID:In-Reply-To:Date:References :Subject:Cc:To:From:Sender:Reply-To:Content-Transfer-Encoding:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=yMn+g+HR1BNpASIdGn41uIlCyX3tguiNhgGwTjZJQjU=; b=rHaMWjhpJo1TyNkkfWRIm12IXZ K5HLafkUrxChXPYdRpIcQOS3sWTYEi6T+qd/AaliE819PtpfjWaEauOjxk9wOJ/GvSGWXUlAbAQOv 8iw+XPgweCCAwgojoaOWPBV+Q; Received: from 75-166-130-93.hlrn.qwest.net ([75.166.130.93]:33806 helo=prentzel) by box5379.bluehost.com with esmtpsa (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.95) (envelope-from ) id 1pPxik-003dKg-8P; Wed, 08 Feb 2023 20:35:38 -0700 From: Tom Tromey To: Simon Marchi Cc: Tom Tromey , Hannes Domani , Hannes Domani via Gdb-patches Subject: Re: [PATCH] Always create a new value object in valpy_do_cast References: <20230118172740.2171-1-ssbssa.ref@yahoo.de> <20230118172740.2171-1-ssbssa@yahoo.de> <87tu0ijw76.fsf@tromey.com> <861084923.719650.1674411768974@mail.yahoo.com> <87lelujntp.fsf@tromey.com> X-Attribution: Tom Date: Wed, 08 Feb 2023 20:35:35 -0700 In-Reply-To: (Simon Marchi's message of "Wed, 8 Feb 2023 21:08:54 -0500") Message-ID: <87sffflddk.fsf@tromey.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/28.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - box5379.bluehost.com X-AntiAbuse: Original Domain - sourceware.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - tromey.com X-BWhitelist: no X-Source-IP: 75.166.130.93 X-Source-L: No X-Exim-ID: 1pPxik-003dKg-8P X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: 75-166-130-93.hlrn.qwest.net (prentzel) [75.166.130.93]:33806 X-Source-Auth: tom+tromey.com X-Email-Count: 3 X-Source-Cap: ZWx5bnJvYmk7ZWx5bnJvYmk7Ym94NTM3OS5ibHVlaG9zdC5jb20= X-Local-Domain: yes X-Spam-Status: No, score=-3021.3 required=5.0 tests=BAYES_00,DKIM_SIGNED,DKIM_VALID,JMQ_SPF_NEUTRAL,RCVD_IN_DNSWL_NONE,RCVD_IN_MSPIKE_H2,SPF_HELO_NONE,SPF_PASS,TXREP autolearn=no autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org List-Id: >>>>> "Simon" == Simon Marchi writes: >> I think what we probably need is to change how the value_mark API works, >> so that it isn't relying on a value pointer being in all_values, but >> rather return some other type/object that isn't invalidated in the same >> way. Simon> Is there an advantage of that value chain thing vs using value_ref_ptr Simon> throughout? Not replace all `value *` with value_ref_ptr, but have Simon> functions return and accept value_ref_ptr where that makes sense. The chain is used to implement the watchpoint semantics. It's needed, I think, but it would be better if it were opt-in -- that is, some caller has to request it explicitly. However that requires switching to value_ref_ptr everywhere... .. but please don't do that, I'm nearly done with a series to move value to value.h and use methods, and it's reasonably large and would be painful to rebase. Meanwhile I think we have a fix for this bug, the problem is finding a test case. Though... the one we have does fail for Hannes so perhaps that's enough. Tom