Tested aarch64-linux. Pushed to trunk.
-- >8 --
This was changed by LWG 3857.
libstdc++-v3/ChangeLog:
* include/std/string_view (basic_string_view(R&&)): Remove
constraint that traits_type must be the same, as per LWG 3857.
* testsuite/21_strings/basic_string_view/cons/char/range_c++20.cc:
Explicit conversion between different specializations should be
allowed.
* testsuite/21_strings/basic_string_view/cons/wchar_t/range_c++20.cc:
Likewise.
---
libstdc++-v3/include/std/string_view | 2 --
.../cons/char/range_c++20.cc | 21 ++++---------------
.../cons/wchar_t/range_c++20.cc | 21 ++++---------------
3 files changed, 8 insertions(+), 36 deletions(-)
diff --git a/libstdc++-v3/include/std/string_view
b/libstdc++-v3/include/std/string_view
index b444b5b9a39..e30a9c1768e 100644
--- a/libstdc++-v3/include/std/string_view
+++ b/libstdc++-v3/include/std/string_view
@@ -167,8 +167,6 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
&& (!requires (_DRange& __d) {
__d.operator ::std::basic_string_view<_CharT, _Traits>();
})
- && (!requires { typename _DRange::traits_type; }
- || is_same_v<typename _DRange::traits_type, _Traits>)
constexpr explicit
basic_string_view(_Range&& __r)
noexcept(noexcept(ranges::size(__r)) && noexcept(ranges::data(__r)))
diff --git
a/libstdc++-v3/testsuite/21_strings/basic_string_view/cons/char/range_c++20.cc
b/libstdc++-v3/testsuite/21_strings/basic_string_view/cons/char/range_c++20.cc
index 5d0396563fd..bae8da1d264 100644
---
a/libstdc++-v3/testsuite/21_strings/basic_string_view/cons/char/range_c++20.cc
+++
b/libstdc++-v3/testsuite/21_strings/basic_string_view/cons/char/range_c++20.cc
@@ -115,23 +115,10 @@ test02()
static_assert( ! std::is_constructible_v<std::string_view, V1> );
using V2 = std::basic_string_view<char, __gnu_cxx::char_traits<char>>;
- // V2::traits_type is not the right type
- static_assert( ! std::is_constructible_v<std::string_view, V2> );
-
- struct V3 : V2
- {
- private:
- using V2::traits_type;
- };
- // V3::traits_type is not a valid (accessible) type
- static_assert( std::is_constructible_v<std::string_view, V3> );
-
- struct V4 : V2
- {
- using traits_type = std::string_view::traits_type;
- };
- // V4::traits_type is the right type
- static_assert( std::is_constructible_v<std::string_view, V4> );
+ // LWG 3857
+ // basic_string_view should allow explicit conversion when only traits vary
+ static_assert( std::is_constructible_v<std::string_view, V2> );
+ static_assert( ! std::is_convertible_v<V2, std::string_view> );
}
void
diff --git
a/libstdc++-v3/testsuite/21_strings/basic_string_view/cons/wchar_t/range_c++20.cc
b/libstdc++-v3/testsuite/21_strings/basic_string_view/cons/wchar_t/range_c++20.cc
index d6996a1dd6f..3cf154d8602 100644
---
a/libstdc++-v3/testsuite/21_strings/basic_string_view/cons/wchar_t/range_c++20.cc
+++
b/libstdc++-v3/testsuite/21_strings/basic_string_view/cons/wchar_t/range_c++20.cc
@@ -115,23 +115,10 @@ test02()
static_assert( ! std::is_constructible_v<std::wstring_view, V1> );
using V2 = std::basic_string_view<wchar_t, __gnu_cxx::char_traits<wchar_t>>;
- // V2::traits_type is not the right type
- static_assert( ! std::is_constructible_v<std::wstring_view, V2> );
-
- struct V3 : V2
- {
- private:
- using V2::traits_type;
- };
- // V3::traits_type is not a valid (accessible) type
- static_assert( std::is_constructible_v<std::wstring_view, V3> );
-
- struct V4 : V2
- {
- using traits_type = std::wstring_view::traits_type;
- };
- // V4::traits_type is the right type
- static_assert( std::is_constructible_v<std::wstring_view, V4> );
+ // LWG 3857
+ // basic_string_view should allow explicit conversion when only traits vary
+ static_assert( std::is_constructible_v<std::wstring_view, V2> );
+ static_assert( ! std::is_convertible_v<V2, std::wstring_view> );
}
void
--
2.43.0
