diff options
author | Jonathan Wakely <jwakely@redhat.com> | 2020-01-27 10:30:03 +0000 |
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committer | Jonathan Wakely <jwakely@redhat.com> | 2020-01-27 10:55:19 +0000 |
commit | 389cd88ce797e2a4345eab8db478a3b8eba798e8 (patch) | |
tree | 26224fd954b7b85b5d52be5c32de1e632ac60587 | |
parent | e648e57efca6ce6d751ef8c2038608817b514fb4 (diff) | |
download | gcc-389cd88ce797e2a4345eab8db478a3b8eba798e8.tar.gz |
libstdc++: Fix deduction guide for std::span (PR93426)
The deduction guide from an iterator and sentinel used the wrong alias
template and so didn't work.
PR libstdc++/93426
* include/std/span (span): Fix deduction guide.
* testsuite/23_containers/span/deduction.cc: New test.
-rw-r--r-- | libstdc++-v3/ChangeLog | 6 | ||||
-rw-r--r-- | libstdc++-v3/include/std/span | 4 | ||||
-rw-r--r-- | libstdc++-v3/testsuite/23_containers/span/deduction.cc | 84 |
3 files changed, 92 insertions, 2 deletions
diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog index 0067e581acb..2b877a8b44d 100644 --- a/libstdc++-v3/ChangeLog +++ b/libstdc++-v3/ChangeLog @@ -1,3 +1,9 @@ +2020-01-27 Jonathan Wakely <jwakely@redhat.com> + + PR libstdc++/93426 + * include/std/span (span): Fix deduction guide. + * testsuite/23_containers/span/deduction.cc: New test. + 2020-01-24 Jonathan Wakely <jwakely@redhat.com> * libsupc++/compare (__cmp_cat::_Eq): Remove enumeration type. diff --git a/libstdc++-v3/include/std/span b/libstdc++-v3/include/std/span index 0dae18672af..0072010dea8 100644 --- a/libstdc++-v3/include/std/span +++ b/libstdc++-v3/include/std/span @@ -190,7 +190,6 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION : span(static_cast<pointer>(__arr.data()), _ArrayExtent) { } - public: template<ranges::contiguous_range _Range> requires (_Extent == dynamic_extent) && (!__detail::__is_std_span<remove_cvref_t<_Range>>::value) @@ -404,6 +403,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION }; // deduction guides + template<typename _Type, size_t _ArrayExtent> span(_Type(&)[_ArrayExtent]) -> span<_Type, _ArrayExtent>; @@ -416,7 +416,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION template<contiguous_iterator _Iter, typename _Sentinel> span(_Iter, _Sentinel) - -> span<remove_reference_t<ranges::range_reference_t<_Iter>>>; + -> span<remove_reference_t<iter_reference_t<_Iter>>>; template<typename _Range> span(_Range &&) diff --git a/libstdc++-v3/testsuite/23_containers/span/deduction.cc b/libstdc++-v3/testsuite/23_containers/span/deduction.cc new file mode 100644 index 00000000000..66e955e961b --- /dev/null +++ b/libstdc++-v3/testsuite/23_containers/span/deduction.cc @@ -0,0 +1,84 @@ +// 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 +// <http://www.gnu.org/licenses/>. + +// { dg-options "-std=gnu++2a" } +// { dg-do compile { target c++2a } } + +#include <span> + +template<typename T, int N, typename U> +constexpr bool is_static_span(const U&) +{ + return std::is_same_v<std::span<T, N>, U> && N != std::dynamic_extent; +} + +template<typename T, typename U> +constexpr bool is_dynamic_span(const U&) +{ + return std::is_same_v<std::span<T>, U>; +} + +struct Range +{ + float* begin() const; + float* end() const; +}; + +void +test01() +{ + const char c[] = ""; + int i[2]{}; + std::array<long, 3> a; + Range r; + + std::span s1(c); + static_assert( is_static_span<const char, 1>(s1) ); + + std::span s2(i); + static_assert( is_static_span<int, 2>(s2) ); + + std::span s3(a); + static_assert( is_static_span<long, 3>(s3) ); + + std::span s4(const_cast<const std::array<long, 3>&>(a)); + static_assert( is_static_span<const long, 3>(s4) ); + + std::span s5(std::begin(i), std::end(i)); + static_assert( is_dynamic_span<int>(s5) ); + + std::span s6(std::cbegin(i), std::cend(i)); + static_assert( is_dynamic_span<const int>(s6) ); + + std::span s7(r); + static_assert( is_dynamic_span<float>(s7) ); + + std::span s8(s1); + static_assert( is_static_span<const char, 1>(s8) ); + + std::span s9(s2); + static_assert( is_static_span<int, 2>(s9) ); + + std::span s10(const_cast<std::span<int, 2>&>(s2)); + static_assert( is_static_span<int, 2>(s10) ); + + std::span s11(s5); + static_assert( is_dynamic_span<int>(s11) ); + + std::span s12(const_cast<const std::span<int>&>(s5)); + static_assert( is_dynamic_span<int>(s12) ); +} |