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 [216.205.24.124]) by sourceware.org (Postfix) with ESMTPS id 0A7493858D39 for ; Tue, 19 Oct 2021 18:29:33 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 0A7493858D39 Received: from mail-qt1-f197.google.com (mail-qt1-f197.google.com [209.85.160.197]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-353-gFcfQC-DOgaGt1D6UdVudQ-1; Tue, 19 Oct 2021 14:29:32 -0400 X-MC-Unique: gFcfQC-DOgaGt1D6UdVudQ-1 Received: by mail-qt1-f197.google.com with SMTP id w12-20020ac80ecc000000b002a7a4cd22faso571399qti.4 for ; Tue, 19 Oct 2021 11:29:32 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=tvM1xHTpjZT/FQmIpidewMaWqYkutr6VpIxQM1Y8f74=; b=TmavrKfnYWZj5gQ0Plg0ISlImkc4a+5jKvhAw14L9ysHpo0DaBWWOkAGQ2w9+vxwH1 tCcWhtKVVWZMblZNWgbZtLhRgA5LaP4WSIGLJWQaJ04JTNapfH7UK75WKVBgCzUriYXF iVrTgl3TQOU+4wli4zfbxKW3PHRmlO0++O5qKHD2UkXCwksTXd8yIrCTx/L0uAEFDPCU Omb5N4I1exzjJcO9rzEb2nqRLB0jBCYL9d23OKagoGLGeDuUvLcvAkZjIIiLUlUm9YeW ils8+dAU0+AqU58dOqwIfKL3zJEOiApoSaDNcUgA/5nimpAioKR9oP5kVvyYx7yOFbFP KIFg== X-Gm-Message-State: AOAM531ybn4phdpki7ZAL+FVdWjQts0XVqf4ShGWfMa+1/PTrKAgPfMU JIlJ+LDGPpjdOWaSSkRIkrjKnmwruK5sydDqCf5W/XLz0TJXxWqH5k7ToGhbfYbz+utW5yX86Zg TfLV7jWJvEasyKOQ= X-Received: by 2002:a0c:e409:: with SMTP id o9mr1511189qvl.53.1634668171960; Tue, 19 Oct 2021 11:29:31 -0700 (PDT) X-Google-Smtp-Source: ABdhPJznvTeHOfBZ7NrFccKptVF5WpPHugEiO11cSgsykVzE013UeNWRTLnAx+Nxl2GNeXsDYUtTNw== X-Received: by 2002:a0c:e409:: with SMTP id o9mr1511178qvl.53.1634668171770; Tue, 19 Oct 2021 11:29:31 -0700 (PDT) Received: from localhost.localdomain (ool-457d493a.dyn.optonline.net. [69.125.73.58]) by smtp.gmail.com with ESMTPSA id m14sm7875422qtq.74.2021.10.19.11.29.30 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 19 Oct 2021 11:29:31 -0700 (PDT) From: Patrick Palka To: gcc-patches@gcc.gnu.org Cc: libstdc++@gcc.gnu.org, Patrick Palka Subject: [PATCH] libstdc++: Implement LWG 3470 change to ranges::subrange Date: Tue, 19 Oct 2021 14:29:15 -0400 Message-Id: <20211019182915.1694049-1-ppalka@redhat.com> X-Mailer: git-send-email 2.33.1.711.g9d530dc002 MIME-Version: 1.0 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset="US-ASCII" X-Spam-Status: No, score=-15.7 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, RCVD_IN_DNSWL_LOW, RCVD_IN_MSPIKE_H2, SPF_HELO_NONE, SPF_NONE, TXREP autolearn=ham autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) 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: Tue, 19 Oct 2021 18:29:36 -0000 Tested on x86_64-pc-linux-gnu, does this look OK for trunk and branches? libstdc++-v3/ChangeLog: * include/bits/ranges_util.h (__detail::__uses_nonqualification_pointer_conversion): Define and use it ... (__convertible_to_nonslicing): ... here, as per LWG 3470. * testsuite/std/ranges/subrange/1.cc: New test. --- libstdc++-v3/include/bits/ranges_util.h | 13 +++++++++---- .../testsuite/std/ranges/subrange/1.cc | 19 +++++++++++++++++++ 2 files changed, 28 insertions(+), 4 deletions(-) create mode 100644 libstdc++-v3/testsuite/std/ranges/subrange/1.cc diff --git a/libstdc++-v3/include/bits/ranges_util.h b/libstdc++-v3/include/bits/ranges_util.h index 7e7b958d274..765848e327d 100644 --- a/libstdc++-v3/include/bits/ranges_util.h +++ b/libstdc++-v3/include/bits/ranges_util.h @@ -184,11 +184,16 @@ namespace ranges namespace __detail { - template + template + concept __uses_nonqualification_pointer_conversion + = is_pointer_v<_From> && is_pointer_v<_To> + && !convertible_to(*)[], + remove_pointer_t<_To>(*)[]>; + + template concept __convertible_to_non_slicing = convertible_to<_From, _To> - && !(is_pointer_v> && is_pointer_v> - && __different_from>, - remove_pointer_t>>); + && !__uses_nonqualification_pointer_conversion, + decay_t<_To>>; template concept __pair_like diff --git a/libstdc++-v3/testsuite/std/ranges/subrange/1.cc b/libstdc++-v3/testsuite/std/ranges/subrange/1.cc new file mode 100644 index 00000000000..8a53261c78c --- /dev/null +++ b/libstdc++-v3/testsuite/std/ranges/subrange/1.cc @@ -0,0 +1,19 @@ +// { dg-options "-std=gnu++20" } +// { dg-do run { target c++20 } } + +#include + +void +test01() +{ + // LWG 3470 + int a[3] = {1,2,3}; + int* b[3] = {&a[2], &a[0], &a[1]}; + auto c = std::ranges::subrange(b); +} + +int +main() +{ + test01(); +} -- 2.33.1.711.g9d530dc002