Date: Sat, 25 Apr 2026 14:20:09 +0000 From: Dimitry Andric <dim@FreeBSD.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org Cc: Dimitry Andric <dimitry@andric.com> Subject: git: bb6713d38cc0 - main - libcxx-compat: revert llvmorg-21-init-15984-g650b451d0065: Message-ID: <69eccd99.375eb.2b39e3c3@gitrepo.freebsd.org>
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The branch main has been updated by dim: URL: https://cgit.FreeBSD.org/src/commit/?id=bb6713d38cc0d988378394f599d81d3a83dbaf03 commit bb6713d38cc0d988378394f599d81d3a83dbaf03 Author: Dimitry Andric <dimitry@andric.com> AuthorDate: 2026-01-04 19:43:58 +0000 Commit: Dimitry Andric <dim@FreeBSD.org> CommitDate: 2026-04-25 14:14:20 +0000 libcxx-compat: revert llvmorg-21-init-15984-g650b451d0065: [libc++] Simplify the implementation of pointer_traits a bit (#142260) This is part of making libc++ 21 build with clang 18. PR: 292067 MFC after: 1 month --- .../libcxx/include/__memory/pointer_traits.h | 116 +++++++++++++++------ 1 file changed, 83 insertions(+), 33 deletions(-) diff --git a/contrib/llvm-project/libcxx/include/__memory/pointer_traits.h b/contrib/llvm-project/libcxx/include/__memory/pointer_traits.h index 8c7f8dff1b76..879b387b9ad1 100644 --- a/contrib/llvm-project/libcxx/include/__memory/pointer_traits.h +++ b/contrib/llvm-project/libcxx/include/__memory/pointer_traits.h @@ -16,13 +16,11 @@ #include <__type_traits/conditional.h> #include <__type_traits/conjunction.h> #include <__type_traits/decay.h> -#include <__type_traits/detected_or.h> #include <__type_traits/enable_if.h> #include <__type_traits/integral_constant.h> #include <__type_traits/is_class.h> #include <__type_traits/is_function.h> #include <__type_traits/is_void.h> -#include <__type_traits/nat.h> #include <__type_traits/void_t.h> #include <__utility/declval.h> #include <__utility/forward.h> @@ -36,37 +34,67 @@ _LIBCPP_PUSH_MACROS _LIBCPP_BEGIN_NAMESPACE_STD +// clang-format off +#define _LIBCPP_CLASS_TRAITS_HAS_XXX(NAME, PROPERTY) \ + template <class _Tp, class = void> \ + struct NAME : false_type {}; \ + template <class _Tp> \ + struct NAME<_Tp, __void_t<typename _Tp::PROPERTY> > : true_type {} +// clang-format on + +_LIBCPP_CLASS_TRAITS_HAS_XXX(__has_pointer, pointer); +_LIBCPP_CLASS_TRAITS_HAS_XXX(__has_element_type, element_type); + +template <class _Ptr, bool = __has_element_type<_Ptr>::value> +struct __pointer_traits_element_type {}; + template <class _Ptr> -struct __pointer_traits_element_type_impl {}; +struct __pointer_traits_element_type<_Ptr, true> { + using type _LIBCPP_NODEBUG = typename _Ptr::element_type; +}; template <template <class, class...> class _Sp, class _Tp, class... _Args> -struct __pointer_traits_element_type_impl<_Sp<_Tp, _Args...> > { +struct __pointer_traits_element_type<_Sp<_Tp, _Args...>, true> { + using type _LIBCPP_NODEBUG = typename _Sp<_Tp, _Args...>::element_type; +}; + +template <template <class, class...> class _Sp, class _Tp, class... _Args> +struct __pointer_traits_element_type<_Sp<_Tp, _Args...>, false> { using type _LIBCPP_NODEBUG = _Tp; }; -template <class _Ptr, class = void> -struct __pointer_traits_element_type : __pointer_traits_element_type_impl<_Ptr> {}; +template <class _Tp, class = void> +struct __has_difference_type : false_type {}; + +template <class _Tp> +struct __has_difference_type<_Tp, __void_t<typename _Tp::difference_type> > : true_type {}; + +template <class _Ptr, bool = __has_difference_type<_Ptr>::value> +struct __pointer_traits_difference_type { + using type _LIBCPP_NODEBUG = ptrdiff_t; +}; template <class _Ptr> -struct __pointer_traits_element_type<_Ptr, __void_t<typename _Ptr::element_type> > { - using type _LIBCPP_NODEBUG = typename _Ptr::element_type; +struct __pointer_traits_difference_type<_Ptr, true> { + using type _LIBCPP_NODEBUG = typename _Ptr::difference_type; }; template <class _Tp, class _Up> -struct __pointer_traits_rebind_impl { - static_assert(false, "Cannot rebind pointer; did you forget to add a rebind member to your pointer?"); -}; +struct __has_rebind { +private: + template <class _Xp> + static false_type __test(...); + _LIBCPP_SUPPRESS_DEPRECATED_PUSH + template <class _Xp> + static true_type __test(typename _Xp::template rebind<_Up>* = 0); + _LIBCPP_SUPPRESS_DEPRECATED_POP -template <template <class, class...> class _Sp, class _Tp, class... _Args, class _Up> -struct __pointer_traits_rebind_impl<_Sp<_Tp, _Args...>, _Up> { - using type _LIBCPP_NODEBUG = _Sp<_Up, _Args...>; +public: + static const bool value = decltype(__test<_Tp>(0))::value; }; -template <class _Tp, class _Up, class = void> -struct __pointer_traits_rebind : __pointer_traits_rebind_impl<_Tp, _Up> {}; - -template <class _Tp, class _Up> -struct __pointer_traits_rebind<_Tp, _Up, __void_t<typename _Tp::template rebind<_Up> > > { +template <class _Tp, class _Up, bool = __has_rebind<_Tp, _Up>::value> +struct __pointer_traits_rebind { #ifndef _LIBCPP_CXX03_LANG using type _LIBCPP_NODEBUG = typename _Tp::template rebind<_Up>; #else @@ -74,8 +102,19 @@ struct __pointer_traits_rebind<_Tp, _Up, __void_t<typename _Tp::template rebind< #endif }; -template <class _Tp> -using __difference_type_member _LIBCPP_NODEBUG = typename _Tp::difference_type; +template <template <class, class...> class _Sp, class _Tp, class... _Args, class _Up> +struct __pointer_traits_rebind<_Sp<_Tp, _Args...>, _Up, true> { +#ifndef _LIBCPP_CXX03_LANG + using type _LIBCPP_NODEBUG = typename _Sp<_Tp, _Args...>::template rebind<_Up>; +#else + using type _LIBCPP_NODEBUG = typename _Sp<_Tp, _Args...>::template rebind<_Up>::other; +#endif +}; + +template <template <class, class...> class _Sp, class _Tp, class... _Args, class _Up> +struct __pointer_traits_rebind<_Sp<_Tp, _Args...>, _Up, false> { + typedef _Sp<_Up, _Args...> type; +}; template <class _Ptr, class = void> struct __pointer_traits_impl {}; @@ -84,7 +123,7 @@ template <class _Ptr> struct __pointer_traits_impl<_Ptr, __void_t<typename __pointer_traits_element_type<_Ptr>::type> > { typedef _Ptr pointer; typedef typename __pointer_traits_element_type<pointer>::type element_type; - using difference_type = __detected_or_t<ptrdiff_t, __difference_type_member, pointer>; + typedef typename __pointer_traits_difference_type<pointer>::type difference_type; #ifndef _LIBCPP_CXX03_LANG template <class _Up> @@ -96,6 +135,9 @@ struct __pointer_traits_impl<_Ptr, __void_t<typename __pointer_traits_element_ty }; #endif // _LIBCPP_CXX03_LANG +private: + struct __nat {}; + public: _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 static pointer pointer_to(__conditional_t<is_void<element_type>::value, __nat, element_type>& __r) { @@ -122,6 +164,9 @@ struct pointer_traits<_Tp*> { }; #endif +private: + struct __nat {}; + public: _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 static pointer pointer_to(__conditional_t<is_void<element_type>::value, __nat, element_type>& __r) _NOEXCEPT { @@ -212,26 +257,20 @@ template <class _Tp> struct __pointer_of {}; template <class _Tp> -concept __has_pointer_member = requires { typename _Tp::pointer; }; - -template <class _Tp> -concept __has_element_type_member = requires { typename _Tp::element_type; }; - -template <class _Tp> - requires __has_pointer_member<_Tp> + requires(__has_pointer<_Tp>::value) struct __pointer_of<_Tp> { using type _LIBCPP_NODEBUG = typename _Tp::pointer; }; template <class _Tp> - requires(!__has_pointer_member<_Tp> && __has_element_type_member<_Tp>) + requires(!__has_pointer<_Tp>::value && __has_element_type<_Tp>::value) struct __pointer_of<_Tp> { using type _LIBCPP_NODEBUG = typename _Tp::element_type*; }; template <class _Tp> - requires(!__has_pointer_member<_Tp> && !__has_element_type_member<_Tp> && - __has_element_type_member<pointer_traits<_Tp>>) + requires(!__has_pointer<_Tp>::value && !__has_element_type<_Tp>::value && + __has_element_type<pointer_traits<_Tp>>::value) struct __pointer_of<_Tp> { using type _LIBCPP_NODEBUG = typename pointer_traits<_Tp>::element_type*; }; @@ -239,8 +278,19 @@ struct __pointer_of<_Tp> { template <typename _Tp> using __pointer_of_t _LIBCPP_NODEBUG = typename __pointer_of<_Tp>::type; +template <class _Tp, class _Up> +struct __pointer_of_or { + using type _LIBCPP_NODEBUG = _Up; +}; + +template <class _Tp, class _Up> + requires requires { typename __pointer_of_t<_Tp>; } +struct __pointer_of_or<_Tp, _Up> { + using type _LIBCPP_NODEBUG = __pointer_of_t<_Tp>; +}; + template <typename _Tp, typename _Up> -using __pointer_of_or_t _LIBCPP_NODEBUG = __detected_or_t<_Up, __pointer_of_t, _Tp>; +using __pointer_of_or_t _LIBCPP_NODEBUG = typename __pointer_of_or<_Tp, _Up>::type; template <class _Smart> concept __resettable_smart_pointer = requires(_Smart __s) { __s.reset(); };home | help
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