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 ESMTPS id 6EF6A3858CD1 for ; Fri, 14 Jul 2023 17:17:46 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 6EF6A3858CD1 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=1689355065; h=from:from:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:mime-version:mime-version: content-type:content-type:in-reply-to:in-reply-to: references:references; bh=eCXD1i9asMyV2o0vLgFaFlh3INAzWAt4DzIgeAfz7Qc=; b=W4onsX+z5ehElXjRHamAUY7sQtVNY14YbB92Zuh5g0XRZND0lXibxMUSTRXK/J6Ty195gG IzevZ13y5S3HKr48pIWB0R878/faiE7VGh2I8t7VaOpMKGdbL5EgBxQZDj7h5otQraYXcq tGBU4KbNGuHqJmYT9z/Si6e/aV5ZnIw= 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-122-yqBKdYKeNEW1-pYbZnQ6XA-1; Fri, 14 Jul 2023 13:17:42 -0400 X-MC-Unique: yqBKdYKeNEW1-pYbZnQ6XA-1 Received: from smtp.corp.redhat.com (int-mx10.intmail.prod.int.rdu2.redhat.com [10.11.54.10]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id BEB59800159; Fri, 14 Jul 2023 17:17:41 +0000 (UTC) Received: from tucnak.zalov.cz (unknown [10.45.224.10]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 62264492C13; Fri, 14 Jul 2023 17:17:41 +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 36EHHcAY4041420 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NOT); Fri, 14 Jul 2023 19:17:38 +0200 Received: (from jakub@localhost) by tucnak.zalov.cz (8.17.1/8.17.1/Submit) id 36EHHbRp4041419; Fri, 14 Jul 2023 19:17:37 +0200 Date: Fri, 14 Jul 2023 19:17:36 +0200 From: Jakub Jelinek To: gcc-patches@gcc.gnu.org, joseph@codesourcery.com, polacek@redhat.com, jason@redhat.com, nathan@acm.org, richard.sandiford@arm.com Subject: Re: [WIP RFC] Add support for keyword-based attributes Message-ID: Reply-To: Jakub Jelinek References: MIME-Version: 1.0 In-Reply-To: X-Scanned-By: MIMEDefang 3.1 on 10.11.54.10 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=-3.4 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_H4,RCVD_IN_MSPIKE_WL,SPF_HELO_NONE,SPF_NONE,TXREP,T_SCC_BODY_TEXT_LINE 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, Jul 14, 2023 at 04:56:18PM +0100, Richard Sandiford via Gcc-patches wrote: > Summary: We'd like to be able to specify some attributes using > keywords, rather than the traditional __attribute__ or [[...]] > syntax. Would that be OK? Will defer to C/C++ maintainers, but as you mentioned, there are many attributes which really can't be ignored and change behavior significantly. vector_size is one of those, mode attribute another, no_unique_address another one (changes ABI in various cases), the OpenMP attributes (omp::directive, omp::sequence) can change behavior if -fopenmp, etc. One can easily error with #ifdef __has_cpp_attribute #if !__has_cpp_attribute (arm::whatever) #error arm::whatever attribute unsupported #endif #else #error __has_cpp_attribute unsupported #endif Adding keywords instead of attributes seems to be too ugly to me. Jakub