From afea21f9612545282db95872021d7587c9d5b0d4 Mon Sep 17 00:00:00 2001 From: Jonathan Wakely Date: Thu, 10 Sep 2020 17:09:15 +0100 Subject: [PATCH] libstdc++: Enforce LWG 3472 preconditions on std::counted_iterator libstdc++-v3/ChangeLog: * include/bits/stl_iterator.h (counted_iterator): Add assertions to check preconditions added by LWG 3472. --- libstdc++-v3/include/bits/stl_iterator.h | 20 ++++++++++++++++---- 1 file changed, 16 insertions(+), 4 deletions(-) diff --git a/libstdc++-v3/include/bits/stl_iterator.h b/libstdc++-v3/include/bits/stl_iterator.h index da740e3732e..f29bae92706 100644 --- a/libstdc++-v3/include/bits/stl_iterator.h +++ b/libstdc++-v3/include/bits/stl_iterator.h @@ -2036,13 +2036,19 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION constexpr decltype(auto) operator*() noexcept(noexcept(*_M_current)) - { return *_M_current; } + { + __glibcxx_assert( _M_length > 0 ); + return *_M_current; + } constexpr decltype(auto) operator*() const noexcept(noexcept(*_M_current)) requires __detail::__dereferenceable - { return *_M_current; } + { + __glibcxx_assert( _M_length > 0 ); + return *_M_current; + } constexpr counted_iterator& operator++() @@ -2170,14 +2176,20 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION iter_move(const counted_iterator& __i) noexcept(noexcept(ranges::iter_move(__i._M_current))) requires input_iterator<_It> - { return ranges::iter_move(__i._M_current); } + { + __glibcxx_assert( __i._M_length > 0 ); + return ranges::iter_move(__i._M_current); + } template _It2> friend constexpr void iter_swap(const counted_iterator& __x, const counted_iterator<_It2>& __y) noexcept(noexcept(ranges::iter_swap(__x._M_current, __y._M_current))) - { ranges::iter_swap(__x._M_current, __y._M_current); } + { + __glibcxx_assert( __x._M_length > 0 && __y._M_length > 0 ); + ranges::iter_swap(__x._M_current, __y._M_current); + } private: template friend class counted_iterator; -- 2.30.2