From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 2181) id 61044386103F; Wed, 25 Nov 2020 17:41:19 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 61044386103F MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="utf-8" From: Jonathan Wakely To: gcc-cvs@gcc.gnu.org, libstdc++-cvs@gcc.gnu.org Subject: [gcc r11-5381] libstdc++: Fix missing subsumption in std::iterator_traits [PR 97935] X-Act-Checkin: gcc X-Git-Author: Jonathan Wakely X-Git-Refname: refs/heads/master X-Git-Oldrev: 1a8d1f54de371de88b2604d8c0e4e01306be8870 X-Git-Newrev: 9d908b7fc475b351622fa5630d4874068c789d70 Message-Id: <20201125174119.61044386103F@sourceware.org> Date: Wed, 25 Nov 2020 17:41:19 +0000 (GMT) X-BeenThere: libstdc++-cvs@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libstdc++-cvs mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 25 Nov 2020 17:41:19 -0000 https://gcc.gnu.org/g:9d908b7fc475b351622fa5630d4874068c789d70 commit r11-5381-g9d908b7fc475b351622fa5630d4874068c789d70 Author: Jonathan Wakely Date: Wed Nov 25 17:18:44 2020 +0000 libstdc++: Fix missing subsumption in std::iterator_traits [PR 97935] libstdc++-v3/ChangeLog: PR libstdc++/97935 * include/bits/iterator_concepts.h (__detail::__iter_without_category): New helper concept. (__iterator_traits::__cat): Use __detail::__iter_without_category. * testsuite/24_iterators/associated_types/iterator.traits.cc: New test. Diff: --- libstdc++-v3/include/bits/iterator_concepts.h | 17 ++++--- .../associated_types/iterator.traits.cc | 56 ++++++++++++++++++++++ 2 files changed, 67 insertions(+), 6 deletions(-) diff --git a/libstdc++-v3/include/bits/iterator_concepts.h b/libstdc++-v3/include/bits/iterator_concepts.h index 8ff4f8667dd..6668caa8185 100644 --- a/libstdc++-v3/include/bits/iterator_concepts.h +++ b/libstdc++-v3/include/bits/iterator_concepts.h @@ -357,6 +357,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION template concept __iter_without_nested_types = !__iter_with_nested_types<_Iter>; + + template + concept __iter_without_category + = !requires { typename _Iter::iterator_category; }; + } // namespace __detail template @@ -396,20 +401,20 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION { using type = typename _Iter::iterator_category; }; template - requires (!requires { typename _Iter::iterator_category; } - && __detail::__cpp17_randacc_iterator<_Iter>) + requires __detail::__iter_without_category<_Iter> + && __detail::__cpp17_randacc_iterator<_Iter> struct __cat<_Iter> { using type = random_access_iterator_tag; }; template - requires (!requires { typename _Iter::iterator_category; } - && __detail::__cpp17_bidi_iterator<_Iter>) + requires __detail::__iter_without_category<_Iter> + && __detail::__cpp17_bidi_iterator<_Iter> struct __cat<_Iter> { using type = bidirectional_iterator_tag; }; template - requires (!requires { typename _Iter::iterator_category; } - && __detail::__cpp17_fwd_iterator<_Iter>) + requires __detail::__iter_without_category<_Iter> + && __detail::__cpp17_fwd_iterator<_Iter> struct __cat<_Iter> { using type = forward_iterator_tag; }; diff --git a/libstdc++-v3/testsuite/24_iterators/associated_types/iterator.traits.cc b/libstdc++-v3/testsuite/24_iterators/associated_types/iterator.traits.cc new file mode 100644 index 00000000000..c3549fefaf6 --- /dev/null +++ b/libstdc++-v3/testsuite/24_iterators/associated_types/iterator.traits.cc @@ -0,0 +1,56 @@ +// Copyright (C) 2020 Free Software Foundation, Inc. +// +// This file is part of the GNU ISO C++ Library. This library is free +// software; you can redistribute it and/or modify it under the +// terms of the GNU General Public License as published by the +// Free Software Foundation; either version 3, or (at your option) +// any later version. + +// This library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU General Public License for more details. + +// You should have received a copy of the GNU General Public License along +// with this library; see the file COPYING3. If not see +// . + +// { dg-options "-std=gnu++2a" } +// { dg-do compile { target c++2a } } + +#include + +struct bidi_iterator +{ + // No nested reference and pointer types. + // No iterator_category. + + // cpp17-iterator requirements: + int& operator*() const; + bidi_iterator& operator++(); + bidi_iterator operator++(int); + + // cpp17-input-iterator requirements: + friend bool operator==(const bidi_iterator&, const bidi_iterator&); + using difference_type = long long; + using value_type = int; + + // cpp17-forward-iterator requirements: + bidi_iterator(); + + // cpp17-bidirectional-iterator requirements: + bidi_iterator& operator--(); + bidi_iterator operator--(int); +}; + +void +test01() +{ + // PR libstdc++/97935 + // Missing subsumption in iterator category detection + using namespace std; + static_assert(__detail::__cpp17_bidi_iterator); + static_assert(same_as::iterator_category, + bidirectional_iterator_tag>, + "PR libstdc++/97935"); +}