From 5e88d2d08d464d80bbe5dfd64db954f2dd516b7e Mon Sep 17 00:00:00 2001 From: Ville Voutilainen Date: Wed, 21 Jun 2017 22:53:26 +0300 Subject: [PATCH] PR libstdc++/80675, PR libstdc++/80940 * include/std/istream: (__is_convertible_to_basic_istream_test(basic_istream<_Ch, _Up>*)): New. (__do_is_convertible_to_basic_istream_impl): Likewise. (__is_convertible_to_basic_istream_impl): Likewise. (__is_convertible_to_basic_istream): Use the new base. (__rvalue_istream_type): New. (operator>>(_Istream&&, _Tp&&)): Use the new helper alias for the SFINAE check, convert to the helper alias type before doing the actual extraction. * include/std/ostream: (__is_convertible_to_basic_ostream_test(basic_ostream<_Ch, _Up>*)): New. (__do_is_convertible_to_basic_ostream_impl): Likewise. (__is_convertible_to_basic_ostream_impl): Likewise. (__is_convertible_to_basic_ostream): Use the new base. (__rvalue_ostream_type): New. (operator<<(_Ostream&&, const _Tp&)): Use the new helper alias for the SFINAE check, convert to the helper alias type before doing the actual insertion. * testsuite/27_io/rvalue_streams-2.cc: Add new tests. From-SVN: r249468 --- libstdc++-v3/ChangeLog | 24 ++++++++ libstdc++-v3/include/std/istream | 52 ++++++++++++---- libstdc++-v3/include/std/ostream | 59 ++++++++++++++----- .../testsuite/27_io/rvalue_streams-2.cc | 53 +++++++++++++++++ 4 files changed, 159 insertions(+), 29 deletions(-) diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog index 676eaf8ae55..f2076a479f5 100644 --- a/libstdc++-v3/ChangeLog +++ b/libstdc++-v3/ChangeLog @@ -1,3 +1,27 @@ +2017-06-21 Ville Voutilainen + + PR libstdc++/80675 + PR libstdc++/80940 + * include/std/istream: + (__is_convertible_to_basic_istream_test(basic_istream<_Ch, _Up>*)): New. + (__do_is_convertible_to_basic_istream_impl): Likewise. + (__is_convertible_to_basic_istream_impl): Likewise. + (__is_convertible_to_basic_istream): Use the new base. + (__rvalue_istream_type): New. + (operator>>(_Istream&&, _Tp&&)): Use the new helper alias + for the SFINAE check, convert to the helper alias type before + doing the actual extraction. + * include/std/ostream: + (__is_convertible_to_basic_ostream_test(basic_ostream<_Ch, _Up>*)): New. + (__do_is_convertible_to_basic_ostream_impl): Likewise. + (__is_convertible_to_basic_ostream_impl): Likewise. + (__is_convertible_to_basic_ostream): Use the new base. + (__rvalue_ostream_type): New. + (operator<<(_Ostream&&, const _Tp&)): Use the new helper alias + for the SFINAE check, convert to the helper alias type before + doing the actual insertion. + * testsuite/27_io/rvalue_streams-2.cc: Add new tests. + 2017-06-21 Ramana Radhakrishnan * config/abi/post/aarch64-linux-gnu/baseline_symbols.txt: Update. diff --git a/libstdc++-v3/include/std/istream b/libstdc++-v3/include/std/istream index 85c0a5a2f42..1fa25555771 100644 --- a/libstdc++-v3/include/std/istream +++ b/libstdc++-v3/include/std/istream @@ -908,20 +908,39 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION ws(basic_istream<_CharT, _Traits>& __is); #if __cplusplus >= 201103L + template + basic_istream<_Ch, _Up>& + __is_convertible_to_basic_istream_test(basic_istream<_Ch, _Up>*); + + template + struct __is_convertible_to_basic_istream_impl + { + using __istream_type = void; + }; template - struct __is_convertible_to_basic_istream + using __do_is_convertible_to_basic_istream_impl = + decltype(__is_convertible_to_basic_istream_test + (declval::type*>())); + + template + struct __is_convertible_to_basic_istream_impl + <_Tp, + __void_t<__do_is_convertible_to_basic_istream_impl<_Tp>>> { - template - static basic_istream<_Ch, _Up>& __check(basic_istream<_Ch, _Up>*); + using __istream_type = + __do_is_convertible_to_basic_istream_impl<_Tp>; + }; - static void __check(...); + template + struct __is_convertible_to_basic_istream + : __is_convertible_to_basic_istream_impl<_Tp> + { public: - using istream_type = - decltype(__check(declval::type*>())); - using type = __not_>; + using type = __not_::__istream_type>>; constexpr static bool value = type::value; - }; + }; template struct __is_extractable : false_type {}; @@ -932,6 +951,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION >> declval<_Tp>())>> : true_type {}; + template + using __rvalue_istream_type = + typename __is_convertible_to_basic_istream< + _Istream>::__istream_type; + // [27.7.1.6] Rvalue stream extraction // _GLIBCXX_RESOLVE_LIB_DEFECTS // 2328. Rvalue stream extraction should use perfect forwarding @@ -949,13 +973,15 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION inline typename enable_if<__and_<__not_>, __is_convertible_to_basic_istream<_Istream>, - __is_extractable<_Istream&, _Tp&&>>::value, - typename __is_convertible_to_basic_istream< - _Istream>::istream_type>::type + __is_extractable< + __rvalue_istream_type<_Istream>, + _Tp&&>>::value, + __rvalue_istream_type<_Istream>>::type operator>>(_Istream&& __is, _Tp&& __x) { - __is >> std::forward<_Tp>(__x); - return __is; + __rvalue_istream_type<_Istream> __ret_is = __is; + __ret_is >> std::forward<_Tp>(__x); + return __ret_is; } #endif // C++11 diff --git a/libstdc++-v3/include/std/ostream b/libstdc++-v3/include/std/ostream index 50b70a5080c..f7cab03c841 100644 --- a/libstdc++-v3/include/std/ostream +++ b/libstdc++-v3/include/std/ostream @@ -613,19 +613,39 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION { return __os.flush(); } #if __cplusplus >= 201103L + template + basic_ostream<_Ch, _Up>& + __is_convertible_to_basic_ostream_test(basic_ostream<_Ch, _Up>*); + + template + struct __is_convertible_to_basic_ostream_impl + { + using __ostream_type = void; + }; + + template + using __do_is_convertible_to_basic_ostream_impl = + decltype(__is_convertible_to_basic_ostream_test + (declval::type*>())); + + template + struct __is_convertible_to_basic_ostream_impl + <_Tp, + __void_t<__do_is_convertible_to_basic_ostream_impl<_Tp>>> + { + using __ostream_type = + __do_is_convertible_to_basic_ostream_impl<_Tp>; + }; + template struct __is_convertible_to_basic_ostream - { - template - static basic_ostream<_Ch, _Up>& __check(basic_ostream<_Ch, _Up>*); - - static void __check(...); - public: - using ostream_type = - decltype(__check(declval::type*>())); - using type = __not_>; - constexpr static bool value = type::value; - }; + : __is_convertible_to_basic_ostream_impl<_Tp> + { + public: + using type = __not_::__ostream_type>>; + constexpr static bool value = type::value; + }; template struct __is_insertable : false_type {}; @@ -636,6 +656,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION << declval())>> : true_type {}; + template + using __rvalue_ostream_type = + typename __is_convertible_to_basic_ostream< + _Ostream>::__ostream_type; + /** * @brief Generic inserter for rvalue stream * @param __os An input stream. @@ -650,13 +675,15 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION inline typename enable_if<__and_<__not_>, __is_convertible_to_basic_ostream<_Ostream>, - __is_insertable<_Ostream&, const _Tp&>>::value, - typename __is_convertible_to_basic_ostream< - _Ostream>::ostream_type>::type + __is_insertable< + __rvalue_ostream_type<_Ostream>, + const _Tp&>>::value, + __rvalue_ostream_type<_Ostream>>::type operator<<(_Ostream&& __os, const _Tp& __x) { - __os << __x; - return __os; + __rvalue_ostream_type<_Ostream> __ret_os = __os; + __ret_os << __x; + return __ret_os; } #endif // C++11 diff --git a/libstdc++-v3/testsuite/27_io/rvalue_streams-2.cc b/libstdc++-v3/testsuite/27_io/rvalue_streams-2.cc index 2b46aa1cc69..9c20274d541 100644 --- a/libstdc++-v3/testsuite/27_io/rvalue_streams-2.cc +++ b/libstdc++-v3/testsuite/27_io/rvalue_streams-2.cc @@ -24,11 +24,64 @@ struct A {}; void operator<<(std::ostream&, const A&) { } void operator>>(std::istream&, A&) { } +class MyStream : private std::ostream, private std::istream +{ +public: + MyStream& operator <<(const char*) + { + return *this; + } + MyStream& operator >>(int&) + { + return *this; + } +}; + +class MyStream2 +{ +public: + MyStream2& operator <<(const char*) + { + return *this; + } + MyStream2& operator >>(int&) + { + return *this; + } +private: + operator std::ostream&(); + operator std::istream&(); +}; + +struct X { }; + +std::ostream& operator<<(std::ostream& os, const X&) { return os; } +std::istream& operator>>(std::istream& is, X&&) { return is; } + +struct O : std::ostream { }; + +void operator<<(O&, X) = delete; + +struct I : std::istream { }; + +void operator>>(I&, X) = delete; + // PR libstdc++/65543 +// PR libstdc++/80675 +// PR libstdc++/80940 int main() { A a; std::ostringstream() << a; std::istringstream() >> a; + MyStream stream{}; + stream << "aaa"; + int msi; + stream >> msi; + MyStream2 stream2{}; + stream2 << "aaa"; + stream2 >> msi; + O{} << X{}; + I{} >> X{}; } -- 2.30.2