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 [170.10.133.124]) by sourceware.org (Postfix) with ESMTP id 076663987C09 for ; Thu, 10 Jun 2021 17:26:05 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 076663987C09 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-494-v2aUNKW_NaSpqNqhsuspUw-1; Thu, 10 Jun 2021 13:26:03 -0400 X-MC-Unique: v2aUNKW_NaSpqNqhsuspUw-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 799DCA40C3 for ; Thu, 10 Jun 2021 17:26:02 +0000 (UTC) Received: from tucnak.zalov.cz (ovpn-114-102.ams2.redhat.com [10.36.114.102]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 257A219C45; Thu, 10 Jun 2021 17:26:01 +0000 (UTC) Received: from tucnak.zalov.cz (localhost [127.0.0.1]) by tucnak.zalov.cz (8.16.1/8.16.1) with ESMTPS id 15AHPxRQ2303857 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NOT); Thu, 10 Jun 2021 19:25:59 +0200 Received: (from jakub@localhost) by tucnak.zalov.cz (8.16.1/8.16.1/Submit) id 15AHPwW32303856; Thu, 10 Jun 2021 19:25:58 +0200 Date: Thu, 10 Jun 2021 19:25:58 +0200 From: Jakub Jelinek To: Jason Merrill Cc: gcc-patches@gcc.gnu.org, Jonathan Wakely Subject: Re: [PATCH] c++: Add C++23 consteval if support - P1938R3 [PR100974] Message-ID: <20210610172558.GC7706@tucnak> Reply-To: Jakub Jelinek References: <20210610083416.GC7746@tucnak> <20210610144408.GH7746@tucnak> MIME-Version: 1.0 In-Reply-To: <20210610144408.GH7746@tucnak> X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit X-Spam-Status: No, score=-5.8 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, RCVD_IN_DNSWL_LOW, RCVD_IN_MSPIKE_H4, RCVD_IN_MSPIKE_WL, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: gcc-patches@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 10 Jun 2021 17:26:07 -0000 On Thu, Jun 10, 2021 at 04:44:09PM +0200, Jakub Jelinek wrote: > > Maybe use cp_parser_compound_statement directly instead of this and checking > > CPP_OPEN_BRACE above? Either way is fine. > > I thought doing it this way will provide better diagnostics for what I think > can be a common bug - people so used to normal if not requiring compound > statements forgetting those {}s from time to time. What the patch currently diagnoses is: consteval-if2.C:13:6: error: ‘if consteval’ requires compound statement 13 | if consteval if (true) {} // { dg-error "'if consteval' requires compound statement" } | ^~~~~~~~~ while with cp_parser_compound_statement directly it diagnoses: consteval-if2.C:13:16: error: expected ‘{’ before ‘if’ 13 | if consteval if (true) {} // { dg-error "'if consteval' requires compound statement" } | ^~ What do you prefer? Dunno if the fine detail that in the grammar only one of the statements is compound-statement and then there is a requirement that the other statement has to be a compound-statement shouldn't affect how it is reported. Jakub