Message ID | 20230511201847.1056247-1-jwakely@redhat.com |
---|---|
State | New |
Headers | show |
Series | [committed] libstdc++: Enforce value_type consistency in strings and streams | expand |
On Thu, 11 May 2023 at 21:20, Jonathan Wakely via Libstdc++ < libstdc++@gcc.gnu.org> wrote: > Tested powerpc64le-linux. Pushed to trunk. > > I don't plan to backport the assertions, because they're an API change > that isn't suitable for the branches. But removing _Alloc_traits_impl > and replacing it with _S_allocate should be done for gcc-13 to keep the > contents of the two libstdc++.so.6.0.32 libraries in sync. > > Here's the gcc-13 backport. No new assertions, just the new exported symbol. commit 0d5a359140503d26adf11325e1f9a09ba7067dfc Author: Jonathan Wakely <jwakely@redhat.com> Date: Wed May 10 21:30:10 2023 libstdc++: Backport std::basic_string::_S_allocate from trunk This is a backport of r14-739-gc62e945492afbb to keep the exported symbol list consistent between trunk and gcc-13. The new assertions from that commit are not part of this backport. libstdc++-v3/ChangeLog: * config/abi/pre/gnu.ver: Export basic_string::_S_allocate. * include/bits/basic_string.h: (basic_string::_Alloc_traits_impl): Remove class template. (basic_string::_S_allocate): New static member function. (basic_string::assign): Use _S_allocate. * include/bits/basic_string.tcc (basic_string::_M_create) (basic_string::reserve, basic_string::_M_replace): Likewise. (cherry picked from commit c62e945492afbbd2a09896fc7b0b07f7e719a606) diff --git a/libstdc++-v3/config/abi/pre/gnu.ver b/libstdc++-v3/config/abi/pre/gnu.ver index 36bb87880d7..768cd4a4a6c 100644 --- a/libstdc++-v3/config/abi/pre/gnu.ver +++ b/libstdc++-v3/config/abi/pre/gnu.ver @@ -1759,7 +1759,9 @@ GLIBCXX_3.4.21 { #endif # ABI-tagged std::basic_string - _ZNSt7__cxx1112basic_stringI[cw]St11char_traitsI[cw]ESaI[cw]EE1[01]**; + _ZNSt7__cxx1112basic_stringI[cw]St11char_traitsI[cw]ESaI[cw]EE10_M_[dr]*; + _ZNSt7__cxx1112basic_stringI[cw]St11char_traitsI[cw]ESaI[cw]EE10_S_compareE[jmy][jmy]; + _ZNSt7__cxx1112basic_stringI[cw]St11char_traitsI[cw]ESaI[cw]EE11_M_capacityE[jmy]; _ZNSt7__cxx1112basic_stringI[cw]St11char_traitsI[cw]ESaI[cw]EE12_Alloc_hiderC[12]EP[cw]RKS3_; _ZNSt7__cxx1112basic_stringI[cw]St11char_traitsI[cw]ESaI[cw]EE12_M*; _ZNSt7__cxx1112basic_stringI[cw]St11char_traitsI[cw]ESaI[cw]EE13*; @@ -2516,6 +2518,7 @@ GLIBCXX_3.4.31 { GLIBCXX_3.4.32 { _ZSt21ios_base_library_initv; + _ZNSt7__cxx1112basic_stringI[cw]St11char_traitsI[cw]ESaI[cw]EE11_S_allocateERS3_[jmy]; } GLIBCXX_3.4.31; # Symbols in the support library (libsupc++) have their own tag. diff --git a/libstdc++-v3/include/bits/basic_string.h b/libstdc++-v3/include/bits/basic_string.h index b16b2898b62..870b4728928 100644 --- a/libstdc++-v3/include/bits/basic_string.h +++ b/libstdc++-v3/include/bits/basic_string.h @@ -89,36 +89,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11 typedef typename __gnu_cxx::__alloc_traits<_Alloc>::template rebind<_CharT>::other _Char_alloc_type; -#if __cpp_lib_constexpr_string < 201907L typedef __gnu_cxx::__alloc_traits<_Char_alloc_type> _Alloc_traits; -#else - template<typename _Traits2, typename _Dummy_for_PR85282> - struct _Alloc_traits_impl : __gnu_cxx::__alloc_traits<_Char_alloc_type> - { - typedef __gnu_cxx::__alloc_traits<_Char_alloc_type> _Base; - - [[__gnu__::__always_inline__]] - static constexpr typename _Base::pointer - allocate(_Char_alloc_type& __a, typename _Base::size_type __n) - { - pointer __p = _Base::allocate(__a, __n); - if (std::is_constant_evaluated()) - // Begin the lifetime of characters in allocated storage. - for (size_type __i = 0; __i < __n; ++__i) - std::construct_at(__builtin_addressof(__p[__i])); - return __p; - } - }; - - template<typename _Dummy_for_PR85282> - struct _Alloc_traits_impl<char_traits<_CharT>, _Dummy_for_PR85282> - : __gnu_cxx::__alloc_traits<_Char_alloc_type> - { - // std::char_traits begins the lifetime of characters. - }; - - using _Alloc_traits = _Alloc_traits_impl<_Traits, void>; -#endif // Types: public: @@ -149,6 +120,22 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11 #endif private: + static _GLIBCXX20_CONSTEXPR pointer + _S_allocate(_Char_alloc_type& __a, size_type __n) + { + pointer __p = _Alloc_traits::allocate(__a, __n); +#if __cpp_lib_constexpr_string >= 201907L + // std::char_traits begins the lifetime of characters, + // but custom traits might not, so do it here. + if constexpr (!is_same_v<_Traits, char_traits<_CharT>>) + if (std::__is_constant_evaluated()) + // Begin the lifetime of characters in allocated storage. + for (size_type __i = 0; __i < __n; ++__i) + std::construct_at(__builtin_addressof(__p[__i])); +#endif + return __p; + } + #if __cplusplus >= 201703L // A helper type for avoiding boiler-plate. typedef basic_string_view<_CharT, _Traits> __sv_type; @@ -1596,7 +1583,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11 const auto __len = __str.size(); auto __alloc = __str._M_get_allocator(); // If this allocation throws there are no effects: - auto __ptr = _Alloc_traits::allocate(__alloc, __len + 1); + auto __ptr = _S_allocate(__alloc, __len + 1); _M_destroy(_M_allocated_capacity); _M_data(__ptr); _M_capacity(__len); diff --git a/libstdc++-v3/include/bits/basic_string.tcc b/libstdc++-v3/include/bits/basic_string.tcc index 99fdbeee5ad..d8a279fc9ed 100644 --- a/libstdc++-v3/include/bits/basic_string.tcc +++ b/libstdc++-v3/include/bits/basic_string.tcc @@ -152,7 +152,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION // NB: Need an array of char_type[__capacity], plus a terminating // null char_type() element. - return _Alloc_traits::allocate(_M_get_allocator(), __capacity + 1); + return _S_allocate(_M_get_allocator(), __capacity + 1); } // NB: This is the special case for Input Iterators, used in @@ -376,8 +376,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION else if (__length < __capacity) try { - pointer __tmp - = _Alloc_traits::allocate(_M_get_allocator(), __length + 1); + pointer __tmp = _S_allocate(_M_get_allocator(), __length + 1); this->_S_copy(__tmp, _M_data(), __length + 1); _M_dispose(); _M_data(__tmp); @@ -521,8 +520,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION #if __cpp_lib_is_constant_evaluated if (std::is_constant_evaluated()) { - auto __newp = _Alloc_traits::allocate(_M_get_allocator(), - __new_size); + auto __newp = _S_allocate(_M_get_allocator(), __new_size); _S_copy(__newp, this->_M_data(), __pos); _S_copy(__newp + __pos, __s, __len2); _S_copy(__newp + __pos + __len2, __p + __len1, __how_much);
diff --git a/libstdc++-v3/config/abi/pre/gnu.ver b/libstdc++-v3/config/abi/pre/gnu.ver index 36bb87880d7..768cd4a4a6c 100644 --- a/libstdc++-v3/config/abi/pre/gnu.ver +++ b/libstdc++-v3/config/abi/pre/gnu.ver @@ -1759,7 +1759,9 @@ GLIBCXX_3.4.21 { #endif # ABI-tagged std::basic_string - _ZNSt7__cxx1112basic_stringI[cw]St11char_traitsI[cw]ESaI[cw]EE1[01]**; + _ZNSt7__cxx1112basic_stringI[cw]St11char_traitsI[cw]ESaI[cw]EE10_M_[dr]*; + _ZNSt7__cxx1112basic_stringI[cw]St11char_traitsI[cw]ESaI[cw]EE10_S_compareE[jmy][jmy]; + _ZNSt7__cxx1112basic_stringI[cw]St11char_traitsI[cw]ESaI[cw]EE11_M_capacityE[jmy]; _ZNSt7__cxx1112basic_stringI[cw]St11char_traitsI[cw]ESaI[cw]EE12_Alloc_hiderC[12]EP[cw]RKS3_; _ZNSt7__cxx1112basic_stringI[cw]St11char_traitsI[cw]ESaI[cw]EE12_M*; _ZNSt7__cxx1112basic_stringI[cw]St11char_traitsI[cw]ESaI[cw]EE13*; @@ -2516,6 +2518,7 @@ GLIBCXX_3.4.31 { GLIBCXX_3.4.32 { _ZSt21ios_base_library_initv; + _ZNSt7__cxx1112basic_stringI[cw]St11char_traitsI[cw]ESaI[cw]EE11_S_allocateERS3_[jmy]; } GLIBCXX_3.4.31; # Symbols in the support library (libsupc++) have their own tag. diff --git a/libstdc++-v3/include/bits/basic_ios.h b/libstdc++-v3/include/bits/basic_ios.h index de5719c1d68..c7c391c0f49 100644 --- a/libstdc++-v3/include/bits/basic_ios.h +++ b/libstdc++-v3/include/bits/basic_ios.h @@ -66,6 +66,10 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION template<typename _CharT, typename _Traits> class basic_ios : public ios_base { +#if __cplusplus >= 202002L + static_assert(is_same_v<_CharT, typename _Traits::char_type>); +#endif + public: ///@{ /** diff --git a/libstdc++-v3/include/bits/basic_string.h b/libstdc++-v3/include/bits/basic_string.h index b16b2898b62..d15f0f0589f 100644 --- a/libstdc++-v3/include/bits/basic_string.h +++ b/libstdc++-v3/include/bits/basic_string.h @@ -86,40 +86,17 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11 template<typename _CharT, typename _Traits, typename _Alloc> class basic_string { +#if __cplusplus >= 202002L + static_assert(is_same_v<_CharT, typename _Traits::char_type>); + static_assert(is_same_v<_CharT, typename _Alloc::value_type>); + using _Char_alloc_type = _Alloc; +#else typedef typename __gnu_cxx::__alloc_traits<_Alloc>::template rebind<_CharT>::other _Char_alloc_type; - -#if __cpp_lib_constexpr_string < 201907L - typedef __gnu_cxx::__alloc_traits<_Char_alloc_type> _Alloc_traits; -#else - template<typename _Traits2, typename _Dummy_for_PR85282> - struct _Alloc_traits_impl : __gnu_cxx::__alloc_traits<_Char_alloc_type> - { - typedef __gnu_cxx::__alloc_traits<_Char_alloc_type> _Base; - - [[__gnu__::__always_inline__]] - static constexpr typename _Base::pointer - allocate(_Char_alloc_type& __a, typename _Base::size_type __n) - { - pointer __p = _Base::allocate(__a, __n); - if (std::is_constant_evaluated()) - // Begin the lifetime of characters in allocated storage. - for (size_type __i = 0; __i < __n; ++__i) - std::construct_at(__builtin_addressof(__p[__i])); - return __p; - } - }; - - template<typename _Dummy_for_PR85282> - struct _Alloc_traits_impl<char_traits<_CharT>, _Dummy_for_PR85282> - : __gnu_cxx::__alloc_traits<_Char_alloc_type> - { - // std::char_traits begins the lifetime of characters. - }; - - using _Alloc_traits = _Alloc_traits_impl<_Traits, void>; #endif + typedef __gnu_cxx::__alloc_traits<_Char_alloc_type> _Alloc_traits; + // Types: public: typedef _Traits traits_type; @@ -149,6 +126,22 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11 #endif private: + static _GLIBCXX20_CONSTEXPR pointer + _S_allocate(_Char_alloc_type& __a, size_type __n) + { + pointer __p = _Alloc_traits::allocate(__a, __n); +#if __cpp_lib_constexpr_string >= 201907L + // std::char_traits begins the lifetime of characters, + // but custom traits might not, so do it here. + if constexpr (!is_same_v<_Traits, char_traits<_CharT>>) + if (std::__is_constant_evaluated()) + // Begin the lifetime of characters in allocated storage. + for (size_type __i = 0; __i < __n; ++__i) + std::construct_at(__builtin_addressof(__p[__i])); +#endif + return __p; + } + #if __cplusplus >= 201703L // A helper type for avoiding boiler-plate. typedef basic_string_view<_CharT, _Traits> __sv_type; @@ -1596,7 +1589,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11 const auto __len = __str.size(); auto __alloc = __str._M_get_allocator(); // If this allocation throws there are no effects: - auto __ptr = _Alloc_traits::allocate(__alloc, __len + 1); + auto __ptr = _S_allocate(__alloc, __len + 1); _M_destroy(_M_allocated_capacity); _M_data(__ptr); _M_capacity(__len); diff --git a/libstdc++-v3/include/bits/basic_string.tcc b/libstdc++-v3/include/bits/basic_string.tcc index 99fdbeee5ad..d8a279fc9ed 100644 --- a/libstdc++-v3/include/bits/basic_string.tcc +++ b/libstdc++-v3/include/bits/basic_string.tcc @@ -152,7 +152,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION // NB: Need an array of char_type[__capacity], plus a terminating // null char_type() element. - return _Alloc_traits::allocate(_M_get_allocator(), __capacity + 1); + return _S_allocate(_M_get_allocator(), __capacity + 1); } // NB: This is the special case for Input Iterators, used in @@ -376,8 +376,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION else if (__length < __capacity) try { - pointer __tmp - = _Alloc_traits::allocate(_M_get_allocator(), __length + 1); + pointer __tmp = _S_allocate(_M_get_allocator(), __length + 1); this->_S_copy(__tmp, _M_data(), __length + 1); _M_dispose(); _M_data(__tmp); @@ -521,8 +520,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION #if __cpp_lib_is_constant_evaluated if (std::is_constant_evaluated()) { - auto __newp = _Alloc_traits::allocate(_M_get_allocator(), - __new_size); + auto __newp = _S_allocate(_M_get_allocator(), __new_size); _S_copy(__newp, this->_M_data(), __pos); _S_copy(__newp + __pos, __s, __len2); _S_copy(__newp + __pos + __len2, __p + __len1, __how_much); diff --git a/libstdc++-v3/testsuite/21_strings/basic_string/requirements/explicit_instantiation/debug.cc b/libstdc++-v3/testsuite/21_strings/basic_string/requirements/explicit_instantiation/debug.cc index b70fbd50460..6bb46c5356c 100644 --- a/libstdc++-v3/testsuite/21_strings/basic_string/requirements/explicit_instantiation/debug.cc +++ b/libstdc++-v3/testsuite/21_strings/basic_string/requirements/explicit_instantiation/debug.cc @@ -19,7 +19,7 @@ #include <debug/string> -// { dg-do compile } +// { dg-do compile { target c++17_down } } // libstdc++/21770 namespace debug = __gnu_debug; diff --git a/libstdc++-v3/testsuite/21_strings/basic_string/requirements/explicit_instantiation/int.cc b/libstdc++-v3/testsuite/21_strings/basic_string/requirements/explicit_instantiation/int.cc index 8326278b36c..4f23cc4dcef 100644 --- a/libstdc++-v3/testsuite/21_strings/basic_string/requirements/explicit_instantiation/int.cc +++ b/libstdc++-v3/testsuite/21_strings/basic_string/requirements/explicit_instantiation/int.cc @@ -20,7 +20,7 @@ #include <string> -// { dg-do compile } +// { dg-do compile { target c++17_down } } // libstdc++/21770 template class std::basic_string<int, std::char_traits<int>,