From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by sourceware.org (Postfix) with ESMTPS id CDC9E3857C51 for ; Fri, 18 Nov 2022 15:14:36 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org CDC9E3857C51 Authentication-Results: sourceware.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=redhat.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1668784476; h=from:from:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:in-reply-to:in-reply-to: references:references; bh=ItfY/kN2M7e+AbPL6553+hQ6oF2q25T1zf0aJszGSxc=; b=Rno1uk+bAZOm18tu4ShFXcHYKSl6QzDwy1hmg9rwroh87vQtwBXFizA4l0VykOlWwdVELI r2L9NPPLJka1KybNUNB2dzWgYjrcGdzUeFpwAPP64r0VbfCZs/LqtknCb2njrg4+kqLPRF 172/o5ZPKmVXBHezZWfocDzmNHrfNdw= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-447-jvy39abHNt2Wq_MnnaheiA-1; Fri, 18 Nov 2022 10:14:32 -0500 X-MC-Unique: jvy39abHNt2Wq_MnnaheiA-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 2DEED811E84 for ; Fri, 18 Nov 2022 15:14:32 +0000 (UTC) Received: from tucnak.zalov.cz (unknown [10.39.192.21]) by smtp.corp.redhat.com (Postfix) with ESMTPS id E403917582; Fri, 18 Nov 2022 15:14:31 +0000 (UTC) Received: from tucnak.zalov.cz (localhost [127.0.0.1]) by tucnak.zalov.cz (8.17.1/8.17.1) with ESMTPS id 2AIFERRZ1901973 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NOT); Fri, 18 Nov 2022 16:14:27 +0100 Received: (from jakub@localhost) by tucnak.zalov.cz (8.17.1/8.17.1/Submit) id 2AIFEQBp1901972; Fri, 18 Nov 2022 16:14:26 +0100 Date: Fri, 18 Nov 2022 16:14:26 +0100 From: Jakub Jelinek To: Marek Polacek Cc: Jason Merrill , Jonathan Wakely , gcc-patches@gcc.gnu.org Subject: Re: [PATCH] c++, v4: Implement C++23 P2647R1 - Permitting static constexpr variables in constexpr functions Message-ID: Reply-To: Jakub Jelinek References: <016f168b-f143-baff-5f71-c48d4611ae11@redhat.com> <740b5e1e-7143-c291-5594-af937867fbc3@redhat.com> MIME-Version: 1.0 In-Reply-To: X-Scanned-By: MIMEDefang 3.1 on 10.11.54.5 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii Content-Disposition: inline X-Spam-Status: No, score=-3.5 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE,RCVD_IN_MSPIKE_H2,SPF_HELO_NONE,SPF_NONE,TXREP autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org List-Id: On Fri, Nov 18, 2022 at 10:03:18AM -0500, Marek Polacek wrote: > > the lambda operator() when still a template as constexpr and then > > cp_finish_decl -> diagnose_static_in_constexpr pedwarns on it. > > For the above perhaps we could figure out there is a static int k; in the > > operator() and don't turn it into constexpr, but what if there is > > something that would e.g. satisfy decl_maybe_constant_var_p but not > > decl_constant_var_p when actually instantiated? > > Without my patch, the diagnostics is in start_decl which isn't called again > > during instantiation, so I presume we mark it as constexpr and then we'd > > diagnose it during constant evaluation. > > Um, can we give up on trying to handle C++17/C++20 then? That was why I've posted the other two variant patches (with the 3rd one being a strict C++23 only change). Even if it is just a temporary state, make C++23 work first and then iterate if it is possible to make C++17/20 working with the pedwarns right. Jakub