| Message ID | 20210517161736.870316-1-ppalka@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | libstdc++: Fix access issues in elements_view::_Sentinel [PR100631] | expand |
On 17/05/21 12:17 -0400, Patrick Palka via Libstdc++ wrote: >Tested on x86_64-pc-linux-gnu, does this look OK for 10/11/trunk? OK, thanks. >libstdc++-v3/ChangeLog: > > PR libstdc++/100631 > * include/std/ranges (elements_view::_Iterator): Befriend > _Sentinel<!_Const>. > (elements_view::_Sentinel::_M_equal): Templatize. > (elements_view::_Sentinel::_M_distance_from): Split out from ... > (elements_view::_Sentinel::operator-): Here. > * testsuite/std/ranges/adaptors/elements.cc (test06, test07): > New tests.
On Mon, May 17, 2021 at 12:21 PM Patrick Palka via Gcc-patches <gcc-patches@gcc.gnu.org> wrote: > > using _Base = elements_view::_Base<_Const>; > sentinel_t<_Base> _M_end = sentinel_t<_Base>(); > @@ -3800,7 +3807,7 @@ namespace views::__adaptor > requires sized_sentinel_for<sentinel_t<_Base>, iterator_t<_Base2>> > friend constexpr range_difference_t<_Base> Preexisting, but this one should be _Base2 - we always want to get the difference type from the iterator being used. > operator-(const _Sentinel& __x, const _Iterator<_Const2>& __y) > - { return __x._M_end - __y._M_current; } > + { return __x._M_distance_from(__y); } >
On Mon, 17 May 2021, Tim Song wrote: > On Mon, May 17, 2021 at 12:21 PM Patrick Palka via Gcc-patches > <gcc-patches@gcc.gnu.org> wrote: > > > > using _Base = elements_view::_Base<_Const>; > > sentinel_t<_Base> _M_end = sentinel_t<_Base>(); > > @@ -3800,7 +3807,7 @@ namespace views::__adaptor > > requires sized_sentinel_for<sentinel_t<_Base>, iterator_t<_Base2>> > > friend constexpr range_difference_t<_Base> > > Preexisting, but this one should be _Base2 - we always want to get the > difference type from the iterator being used. Patch committed with this as a drive-by change. Thanks! -- >8 -- Subject: [PATCH] libstdc++: Fix miscellaneous issues with elements_view::_Sentinel [PR100631] libstdc++-v3/ChangeLog: PR libstdc++/100631 * include/std/ranges (elements_view::_Iterator): Also befriend _Sentinel<!_Const>. (elements_view::_Sentinel::_M_equal): Templatize. (elements_view::_Sentinel::_M_distance_from): Split out from ... (elements_view::_Sentinel::operator-): ... here. Depend on _Base2 instead of _Base in the return type. * testsuite/std/ranges/adaptors/elements.cc (test06, test07): New tests. --- libstdc++-v3/include/std/ranges | 18 +++++++---- .../testsuite/std/ranges/adaptors/elements.cc | 31 +++++++++++++++++++ 2 files changed, 43 insertions(+), 6 deletions(-) diff --git a/libstdc++-v3/include/std/ranges b/libstdc++-v3/include/std/ranges index 48100e9d7f2..36bccd6b33b 100644 --- a/libstdc++-v3/include/std/ranges +++ b/libstdc++-v3/include/std/ranges @@ -3634,16 +3634,22 @@ namespace views::__adaptor requires sized_sentinel_for<iterator_t<_Base>, iterator_t<_Base>> { return __x._M_current - __y._M_current; } - friend _Sentinel<_Const>; + template <bool> friend struct _Sentinel; }; template<bool _Const> struct _Sentinel { private: - constexpr bool - _M_equal(const _Iterator<_Const>& __x) const - { return __x._M_current == _M_end; } + template<bool _Const2> + constexpr bool + _M_equal(const _Iterator<_Const2>& __x) const + { return __x._M_current == _M_end; } + + template<bool _Const2> + constexpr auto + _M_distance_from(const _Iterator<_Const2>& __i) const + { return _M_end - __i._M_current; } using _Base = elements_view::_Base<_Const>; sentinel_t<_Base> _M_end = sentinel_t<_Base>(); @@ -3684,9 +3690,9 @@ namespace views::__adaptor template<bool _Const2, typename _Base2 = __detail::__maybe_const_t<_Const2, _Vp>> requires sized_sentinel_for<sentinel_t<_Base>, iterator_t<_Base2>> - friend constexpr range_difference_t<_Base> + friend constexpr range_difference_t<_Base2> operator-(const _Sentinel& __x, const _Iterator<_Const2>& __y) - { return __x._M_end - __y._M_current; } + { return __x._M_distance_from(__y); } friend _Sentinel<!_Const>; }; diff --git a/libstdc++-v3/testsuite/std/ranges/adaptors/elements.cc b/libstdc++-v3/testsuite/std/ranges/adaptors/elements.cc index 134afd6a873..c6839e38ce5 100644 --- a/libstdc++-v3/testsuite/std/ranges/adaptors/elements.cc +++ b/libstdc++-v3/testsuite/std/ranges/adaptors/elements.cc @@ -115,6 +115,35 @@ test05() VERIFY( r2[0] == 1 && r2[1] == 3 ); } +void +test06() +{ + // PR libstdc++/100631 + auto r = views::iota(0) + | views::filter([](int){ return true; }) + | views::take(42) + | views::reverse + | views::transform([](int) { return std::make_pair(42, "hello"); }) + | views::take(42) + | views::keys; + auto b = r.begin(); + auto e = r.end(); + e - b; +} + +void +test07() +{ + // PR libstdc++/100631 comment #2 + auto r = views::iota(0) + | views::transform([](int) { return std::make_pair(42, "hello"); }) + | views::keys; + auto b = ranges::cbegin(r); + auto e = ranges::end(r); + b.base() == e.base(); + b == e; +} + int main() { @@ -123,4 +152,6 @@ main() test03(); test04(); test05(); + test06(); + test07(); }
diff --git a/libstdc++-v3/include/std/ranges b/libstdc++-v3/include/std/ranges index fe6379fb858..bf52074ca05 100644 --- a/libstdc++-v3/include/std/ranges +++ b/libstdc++-v3/include/std/ranges @@ -3749,15 +3749,22 @@ namespace views::__adaptor { return __x._M_current - __y._M_current; } friend _Sentinel<_Const>; + friend _Sentinel<!_Const>; }; template<bool _Const> struct _Sentinel { private: - constexpr bool - _M_equal(const _Iterator<_Const>& __x) const - { return __x._M_current == _M_end; } + template<bool _Const2> + constexpr bool + _M_equal(const _Iterator<_Const2>& __x) const + { return __x._M_current == _M_end; } + + template<bool _Const2> + constexpr auto + _M_distance_from(const _Iterator<_Const2>& __i) const + { return _M_end - __i._M_current; } using _Base = elements_view::_Base<_Const>; sentinel_t<_Base> _M_end = sentinel_t<_Base>(); @@ -3800,7 +3807,7 @@ namespace views::__adaptor requires sized_sentinel_for<sentinel_t<_Base>, iterator_t<_Base2>> friend constexpr range_difference_t<_Base> operator-(const _Sentinel& __x, const _Iterator<_Const2>& __y) - { return __x._M_end - __y._M_current; } + { return __x._M_distance_from(__y); } friend _Sentinel<!_Const>; }; diff --git a/libstdc++-v3/testsuite/std/ranges/adaptors/elements.cc b/libstdc++-v3/testsuite/std/ranges/adaptors/elements.cc index 134afd6a873..27aba2c0ff0 100644 --- a/libstdc++-v3/testsuite/std/ranges/adaptors/elements.cc +++ b/libstdc++-v3/testsuite/std/ranges/adaptors/elements.cc @@ -115,6 +115,35 @@ test05() VERIFY( r2[0] == 1 && r2[1] == 3 ); } +void +test06() +{ + // PR libstdc++/100631 + auto r = std::views::iota(0) + | std::views::filter([](int){ return true; }) + | std::views::take(42) + | std::views::reverse + | std::views::transform([](int) { return std::make_pair(42, "hello"); }) + | std::views::take(42) + | std::views::keys; + auto b = r.begin(); + auto e = r.end(); + e - b; +} + +void +test07() +{ + // PR libstdc++/100631 comment #2 + auto r = std::views::iota(0) + | std::views::transform([](int) { return std::make_pair(42, "hello"); }) + | std::views::keys; + auto b = std::ranges::cbegin(r); + auto e = std::end(r); + b.base() == e.base(); + b == e; +} + int main() { @@ -123,4 +152,6 @@ main() test03(); test04(); test05(); + test06(); + test07(); }