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 1EF523857C64 for ; Wed, 20 Oct 2021 18:55:55 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 1EF523857C64 Received: from mail-yb1-f199.google.com (mail-yb1-f199.google.com [209.85.219.199]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-242-RDDw3Gq9NBOy3lh1KVXgrA-1; Wed, 20 Oct 2021 14:55:51 -0400 X-MC-Unique: RDDw3Gq9NBOy3lh1KVXgrA-1 Received: by mail-yb1-f199.google.com with SMTP id w201-20020a25dfd2000000b005be4c3971cdso13938751ybg.13 for ; Wed, 20 Oct 2021 11:55:51 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=J3JTtdo59aSpP1aeGshSv7T/YHjdp0RKAdu3BdsGR9Q=; b=bdc1UKAgT+0RevAK+uh0TyTYKgFqlYeRFc0Xi+eBR/LFIoNSegZo2fXqEZ16pLX2Xo XHYy4CP1sTxOgm8I7ROLGSj+enAE9MlI1VZiLNMb6BXIp0y47Rh4OgnEc5YSurc+nQVu bt5gBVlcugP1BhNhHZue2G8MFgxbLCat8eSJyFiDqb0j+G1PqEJQAg1W4SyhqLP5EvPD pOeWKy14eLfasBEex3Zg+AU21KvbtTzbBTJ6Q7qVD2kPyTgumYJzxlHX5C59+1G+BaQf L70xoJcIkl5Oqak2ojWJKr0InlN5IidtLPfV7keAUlLksRwKzHwEzL10TeEnhJALm2H/ NK7w== X-Gm-Message-State: AOAM533fF/ypEW5f4AQDUB4l3J2othLHIsYhmZSGElR2glJWRIahx2as liwRjs+l2hnvcq0tsxw123SNSwQ9QR7Cc+SPxHXTWVABabx5p4x9F7LcVTYNgBzpRbwTvQ+Vlok z12sBr3jM2lklOyi5CqNhrxXs86x9jXI= X-Received: by 2002:a25:29c1:: with SMTP id p184mr885943ybp.198.1634756151335; Wed, 20 Oct 2021 11:55:51 -0700 (PDT) X-Google-Smtp-Source: ABdhPJyrW+QJO9jEYwv9nD1/GiTyb8hOP6ltVjTbw+nh/7EwW0brL2KwT7RcJBEJOnBK22u5EsWQr9+G7FFmHBrchjY= X-Received: by 2002:a25:29c1:: with SMTP id p184mr885931ybp.198.1634756151158; Wed, 20 Oct 2021 11:55:51 -0700 (PDT) MIME-Version: 1.0 References: <20211020165927.1827031-1-ppalka@redhat.com> In-Reply-To: <20211020165927.1827031-1-ppalka@redhat.com> From: Jonathan Wakely Date: Wed, 20 Oct 2021 19:55:40 +0100 Message-ID: Subject: Re: [PATCH] libstdc++: Implement LWG 3481 change to ranges::viewable_range To: Patrick Palka Cc: gcc Patches , "libstdc++" X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset="UTF-8" X-Spam-Status: No, score=-12.6 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=unavailable 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: Wed, 20 Oct 2021 18:55:56 -0000 On Wed, 20 Oct 2021 at 18:01, Patrick Palka wrote: > > Tested on x86_64-pc-linux-gnu, does this look OK for trunk, and branches > after a while? Yes for all. > > libstdc++-v3/ChangeLog: > > * include/bits/ranges_base.h (viewable_range): Adjust as per > LWG 3481. > * testsuite/std/ranges/adaptors/all.cc (test07): New test. > --- > libstdc++-v3/include/bits/ranges_base.h | 3 ++- > libstdc++-v3/testsuite/std/ranges/adaptors/all.cc | 15 +++++++++++++++ > 2 files changed, 17 insertions(+), 1 deletion(-) > > diff --git a/libstdc++-v3/include/bits/ranges_base.h b/libstdc++-v3/include/bits/ranges_base.h > index 7801b2fd023..43b0b9f7bf3 100644 > --- a/libstdc++-v3/include/bits/ranges_base.h > +++ b/libstdc++-v3/include/bits/ranges_base.h > @@ -688,7 +688,8 @@ namespace ranges > /// A range which can be safely converted to a view. > template > concept viewable_range = range<_Tp> > - && (borrowed_range<_Tp> || view>); > + && ((view> && constructible_from, _Tp>) > + || (!view> && borrowed_range<_Tp>)); > > // [range.iter.ops] range iterator operations > > diff --git a/libstdc++-v3/testsuite/std/ranges/adaptors/all.cc b/libstdc++-v3/testsuite/std/ranges/adaptors/all.cc > index 9a6a31e6cb4..ce1384c2890 100644 > --- a/libstdc++-v3/testsuite/std/ranges/adaptors/all.cc > +++ b/libstdc++-v3/testsuite/std/ranges/adaptors/all.cc > @@ -159,6 +159,20 @@ test06() > static_assert(!noexcept(views::all(BorrowedRange(x)))); > } > > +void > +test07() > +{ > + // LWG 3481 > + struct view_t : ranges::empty_view { // move-only view > + view_t(const view_t&) = delete; > + view_t(view_t&&) = default; > + view_t& operator=(const view_t&) = delete; > + view_t& operator=(view_t&&) = default; > + }; > + static_assert(std::movable && !std::copyable); > + static_assert(!ranges::viewable_range); > +} > + > int > main() > { > @@ -168,4 +182,5 @@ main() > static_assert(test04()); > test05(); > test06(); > + test07(); > } > -- > 2.33.1.711.g9d530dc002 >