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 89D883AAB497 for ; Thu, 24 Jun 2021 14:44:12 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 89D883AAB497 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-516-ZuC58_z6M_atsIt_hsbfMw-1; Thu, 24 Jun 2021 10:44:10 -0400 X-MC-Unique: ZuC58_z6M_atsIt_hsbfMw-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id C439F18414AD; Thu, 24 Jun 2021 14:44:09 +0000 (UTC) Received: from tucnak.zalov.cz (ovpn-112-143.ams2.redhat.com [10.36.112.143]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 2C70960C05; Thu, 24 Jun 2021 14:44:09 +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 15OEi63K1297991 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NOT); Thu, 24 Jun 2021 16:44:06 +0200 Received: (from jakub@localhost) by tucnak.zalov.cz (8.16.1/8.16.1/Submit) id 15OEi5Jx1297989; Thu, 24 Jun 2021 16:44:05 +0200 Date: Thu, 24 Jun 2021 16:44:05 +0200 From: Jakub Jelinek To: Jonathan Wakely Cc: Matthias Kretz , gcc Patches , libstdc++ Subject: Re: [PATCH 04/11 v3] libstdc++: Make use of __builtin_bit_cast Message-ID: <20210624144405.GV7746@tucnak> Reply-To: Jakub Jelinek References: <270527782.u9WJ3AIrlG@excalibur> <3553838.ebMzRN9Arp@excalibur> <3315301.e9AK2G76lq@excalibur> <14392010.RDIVbhacDa@minbar> <20210624140837.GT7746@tucnak> <20210624142104.GU7746@tucnak> MIME-Version: 1.0 In-Reply-To: X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 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=-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: libstdc++@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libstdc++ mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 24 Jun 2021 14:44:13 -0000 On Thu, Jun 24, 2021 at 03:40:09PM +0100, Jonathan Wakely wrote: > On Thu, 24 Jun 2021 at 15:34, Jonathan Wakely wrote: > > Rather than use the _GLIBCXX_HAS_BUILTIN macro more widely, I'd prefer > > to not use it where it isn't needed, as in the attached (untested) > > patch. > > My rationale for this is that I'd prefer to use standardized features > like __has_include and __has_cpp_attribute where possible, instead of > adding more and more configure macros. You don't need to look in > c++config.h to see how the macro is defined if you just use a standard > feature directly. > > __has_builtin obviously isn't standardized, but as long as it's > available on all the compilers we care about (which it is) then the > same rationale applies. Okay. Jakub