[libc++] Clean up some now dead code with the upgrade to GCC 14 (#97746)

Author: philnik777

libcxx/include/__config

@@ -162,16 +162,6 @@ _LIBCPP_HARDENING_MODE_DEBUG
 #    define _LIBCPP_CXX03_LANG
 #  endif
 
-// TODO: Remove once we switch to GCC 14
-#  ifndef __has_extension
-#    define __has_extension(__x) 0
-#  endif
-
-// TODO: Remove once we switch to GCC 14
-#  ifndef __has_feature
-#    define __has_feature(__x) 0
-#  endif
-
 #  ifndef __has_constexpr_builtin
 #    define __has_constexpr_builtin(x) 0
 #  endif
@@ -348,44 +338,30 @@ typedef __char32_t char32_t;
 
 #  define _LIBCPP_PREFERRED_ALIGNOF(_Tp) __alignof(_Tp)
 
-#  if defined(_LIBCPP_COMPILER_CLANG_BASED)
-
 // Objective-C++ features (opt-in)
-#    if __has_feature(objc_arc)
-#      define _LIBCPP_HAS_OBJC_ARC
-#    endif
-
-#    if __has_feature(objc_arc_weak)
-#      define _LIBCPP_HAS_OBJC_ARC_WEAK
-#    endif
-
-#    if __has_extension(blocks)
-#      define _LIBCPP_HAS_EXTENSION_BLOCKS
-#    endif
-
-#    if defined(_LIBCPP_HAS_EXTENSION_BLOCKS) && defined(__APPLE__)
-#      define _LIBCPP_HAS_BLOCKS_RUNTIME
-#    endif
-
-#    if !__has_feature(address_sanitizer)
-#      define _LIBCPP_HAS_NO_ASAN
-#    endif
-
-#    define _LIBCPP_ALWAYS_INLINE __attribute__((__always_inline__))
+#  if __has_feature(objc_arc)
+#    define _LIBCPP_HAS_OBJC_ARC
+#  endif
 
-#    define _LIBCPP_DISABLE_EXTENSION_WARNING __extension__
+#  if __has_feature(objc_arc_weak)
+#    define _LIBCPP_HAS_OBJC_ARC_WEAK
+#  endif
 
-#  elif defined(_LIBCPP_COMPILER_GCC)
+#  if __has_extension(blocks)
+#    define _LIBCPP_HAS_EXTENSION_BLOCKS
+#  endif
 
-#    if !defined(__SANITIZE_ADDRESS__)
-#      define _LIBCPP_HAS_NO_ASAN
-#    endif
+#  if defined(_LIBCPP_HAS_EXTENSION_BLOCKS) && defined(__APPLE__)
+#    define _LIBCPP_HAS_BLOCKS_RUNTIME
+#  endif
 
-#    define _LIBCPP_ALWAYS_INLINE __attribute__((__always_inline__))
+#  if !__has_feature(address_sanitizer)
+#    define _LIBCPP_HAS_NO_ASAN
+#  endif
 
-#    define _LIBCPP_DISABLE_EXTENSION_WARNING __extension__
+#  define _LIBCPP_ALWAYS_INLINE __attribute__((__always_inline__))
 
-#  endif // _LIBCPP_COMPILER_[CLANG|GCC]
+#  define _LIBCPP_DISABLE_EXTENSION_WARNING __extension__
 
 #  if defined(_LIBCPP_OBJECT_FORMAT_COFF)
 

libcxx/include/__tuple/tuple_element.h

@@ -40,32 +40,6 @@ struct _LIBCPP_TEMPLATE_VIS tuple_element<_Ip, const volatile _Tp> {
 
 #ifndef _LIBCPP_CXX03_LANG
 
-#  if !__has_builtin(__type_pack_element)
-
-namespace __indexer_detail {
-
-template <size_t _Idx, class _Tp>
-struct __indexed {
-  using type _LIBCPP_NODEBUG = _Tp;
-};
-
-template <class _Types, class _Indexes>
-struct __indexer;
-
-template <class... _Types, size_t... _Idx>
-struct __indexer<__tuple_types<_Types...>, __tuple_indices<_Idx...>> : __indexed<_Idx, _Types>... {};
-
-template <size_t _Idx, class _Tp>
-__indexed<_Idx, _Tp> __at_index(__indexed<_Idx, _Tp> const&);
-
-} // namespace __indexer_detail
-
-template <size_t _Idx, class... _Types>
-using __type_pack_element _LIBCPP_NODEBUG = typename decltype(__indexer_detail::__at_index<_Idx>(
-    __indexer_detail::__indexer< __tuple_types<_Types...>,
-                                 typename __make_tuple_indices<sizeof...(_Types)>::type >{}))::type;
-#  endif
-
 template <size_t _Ip, class... _Types>
 struct _LIBCPP_TEMPLATE_VIS tuple_element<_Ip, __tuple_types<_Types...> > {
   static_assert(_Ip < sizeof...(_Types), "tuple_element index out of range");

libcxx/include/__type_traits/is_function.h

@@ -11,31 +11,19 @@
 
 #include <__config>
 #include <__type_traits/integral_constant.h>
-#include <__type_traits/is_const.h>
-#include <__type_traits/is_reference.h>
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #  pragma GCC system_header
 #endif
 
 _LIBCPP_BEGIN_NAMESPACE_STD
 
-#if __has_builtin(__is_function)
-
 template <class _Tp>
 struct _LIBCPP_TEMPLATE_VIS is_function : integral_constant<bool, __is_function(_Tp)> {};
 
-#else
-
-template <class _Tp>
-struct _LIBCPP_TEMPLATE_VIS is_function
-    : public integral_constant<bool, !(is_reference<_Tp>::value || is_const<const _Tp>::value)> {};
-
-#endif // __has_builtin(__is_function)
-
 #if _LIBCPP_STD_VER >= 17
 template <class _Tp>
-inline constexpr bool is_function_v = is_function<_Tp>::value;
+inline constexpr bool is_function_v = __is_function(_Tp);
 #endif
 
 _LIBCPP_END_NAMESPACE_STD

libcxx/include/__type_traits/is_member_function_pointer.h

@@ -11,31 +11,13 @@
 
 #include <__config>
 #include <__type_traits/integral_constant.h>
-#include <__type_traits/is_function.h>
-#include <__type_traits/remove_cv.h>
-#include <cstddef>
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #  pragma GCC system_header
 #endif
 
 _LIBCPP_BEGIN_NAMESPACE_STD
 
-template <class _Tp>
-struct __libcpp_is_member_pointer {
-  enum { __is_member = false, __is_func = false, __is_obj = false };
-};
-template <class _Tp, class _Up>
-struct __libcpp_is_member_pointer<_Tp _Up::*> {
-  enum {
-    __is_member = true,
-    __is_func   = is_function<_Tp>::value,
-    __is_obj    = !__is_func,
-  };
-};
-
-#if __has_builtin(__is_member_function_pointer)
-
 template <class _Tp>
 struct _LIBCPP_TEMPLATE_VIS is_member_function_pointer : _BoolConstant<__is_member_function_pointer(_Tp)> {};
 
@@ -44,19 +26,6 @@ template <class _Tp>
 inline constexpr bool is_member_function_pointer_v = __is_member_function_pointer(_Tp);
 #  endif
 
-#else // __has_builtin(__is_member_function_pointer)
-
-template <class _Tp>
-struct _LIBCPP_TEMPLATE_VIS is_member_function_pointer
-    : public _BoolConstant<__libcpp_is_member_pointer<__remove_cv_t<_Tp> >::__is_func> {};
-
-#  if _LIBCPP_STD_VER >= 17
-template <class _Tp>
-inline constexpr bool is_member_function_pointer_v = is_member_function_pointer<_Tp>::value;
-#  endif
-
-#endif // __has_builtin(__is_member_function_pointer)
-
 _LIBCPP_END_NAMESPACE_STD
 
 #endif // _LIBCPP___TYPE_TRAITS_IS_MEMBER_FUNCTION_POINTER_H

libcxx/include/__type_traits/is_member_object_pointer.h

@@ -18,8 +18,6 @@
 
 _LIBCPP_BEGIN_NAMESPACE_STD
 
-#if __has_builtin(__is_member_object_pointer)
-
 template <class _Tp>
 struct _LIBCPP_TEMPLATE_VIS is_member_object_pointer : _BoolConstant<__is_member_object_pointer(_Tp)> {};
 
@@ -28,19 +26,6 @@ template <class _Tp>
 inline constexpr bool is_member_object_pointer_v = __is_member_object_pointer(_Tp);
 #  endif
 
-#else // __has_builtin(__is_member_object_pointer)
-
-template <class _Tp>
-struct _LIBCPP_TEMPLATE_VIS is_member_object_pointer
-    : public _BoolConstant<__libcpp_is_member_pointer<__remove_cv_t<_Tp> >::__is_obj> {};
-
-#  if _LIBCPP_STD_VER >= 17
-template <class _Tp>
-inline constexpr bool is_member_object_pointer_v = is_member_object_pointer<_Tp>::value;
-#  endif
-
-#endif // __has_builtin(__is_member_object_pointer)
-
 _LIBCPP_END_NAMESPACE_STD
 
 #endif // _LIBCPP___TYPE_TRAITS_IS_MEMBER_FUNCTION_POINTER_H

libcxx/include/__type_traits/is_member_pointer.h

@@ -11,16 +11,13 @@
 
 #include <__config>
 #include <__type_traits/integral_constant.h>
-#include <__type_traits/is_member_function_pointer.h>
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #  pragma GCC system_header
 #endif
 
 _LIBCPP_BEGIN_NAMESPACE_STD
 
-#if __has_builtin(__is_member_pointer)
-
 template <class _Tp>
 struct _LIBCPP_TEMPLATE_VIS is_member_pointer : _BoolConstant<__is_member_pointer(_Tp)> {};
 
@@ -29,19 +26,6 @@ template <class _Tp>
 inline constexpr bool is_member_pointer_v = __is_member_pointer(_Tp);
 #  endif
 
-#else // __has_builtin(__is_member_pointer)
-
-template <class _Tp>
-struct _LIBCPP_TEMPLATE_VIS is_member_pointer
-    : public _BoolConstant<__libcpp_is_member_pointer<__remove_cv_t<_Tp> >::__is_member> {};
-
-#  if _LIBCPP_STD_VER >= 17
-template <class _Tp>
-inline constexpr bool is_member_pointer_v = is_member_pointer<_Tp>::value;
-#  endif
-
-#endif // __has_builtin(__is_member_pointer)
-
 _LIBCPP_END_NAMESPACE_STD
 
 #endif // _LIBCPP___TYPE_TRAITS_IS_MEMBER_POINTER_H

libcxx/include/__type_traits/is_nothrow_constructible.h

@@ -13,96 +13,35 @@
 #include <__type_traits/add_lvalue_reference.h>
 #include <__type_traits/add_rvalue_reference.h>
 #include <__type_traits/integral_constant.h>
-#include <__type_traits/is_constructible.h>
-#include <__type_traits/is_reference.h>
-#include <__utility/declval.h>
-#include <cstddef>
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #  pragma GCC system_header
 #endif
 
 _LIBCPP_BEGIN_NAMESPACE_STD
 
-// GCC is disabled due to https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106611
-#if __has_builtin(__is_nothrow_constructible) && !defined(_LIBCPP_COMPILER_GCC)
-
 template < class _Tp, class... _Args>
 struct _LIBCPP_TEMPLATE_VIS is_nothrow_constructible
     : public integral_constant<bool, __is_nothrow_constructible(_Tp, _Args...)> {};
-#else
-
-template <bool, bool, class _Tp, class... _Args>
-struct __libcpp_is_nothrow_constructible;
-
-template <class _Tp, class... _Args>
-struct __libcpp_is_nothrow_constructible</*is constructible*/ true, /*is reference*/ false, _Tp, _Args...>
-    : public integral_constant<bool, noexcept(_Tp(std::declval<_Args>()...))> {};
-
-template <class _Tp>
-void __implicit_conversion_to(_Tp) noexcept {}
-
-template <class _Tp, class _Arg>
-struct __libcpp_is_nothrow_constructible</*is constructible*/ true, /*is reference*/ true, _Tp, _Arg>
-    : public integral_constant<bool, noexcept(std::__implicit_conversion_to<_Tp>(std::declval<_Arg>()))> {};
-
-template <class _Tp, bool _IsReference, class... _Args>
-struct __libcpp_is_nothrow_constructible</*is constructible*/ false, _IsReference, _Tp, _Args...> : public false_type {
-};
-
-template <class _Tp, class... _Args>
-struct _LIBCPP_TEMPLATE_VIS is_nothrow_constructible
-    : __libcpp_is_nothrow_constructible<is_constructible<_Tp, _Args...>::value,
-                                        is_reference<_Tp>::value,
-                                        _Tp,
-                                        _Args...> {};
-
-template <class _Tp, size_t _Ns>
-struct _LIBCPP_TEMPLATE_VIS is_nothrow_constructible<_Tp[_Ns]>
-    : __libcpp_is_nothrow_constructible<is_constructible<_Tp>::value, is_reference<_Tp>::value, _Tp> {};
-
-#endif // __has_builtin(__is_nothrow_constructible)
 
 #if _LIBCPP_STD_VER >= 17
 template <class _Tp, class... _Args>
 inline constexpr bool is_nothrow_constructible_v = is_nothrow_constructible<_Tp, _Args...>::value;
 #endif
 
-// TODO: remove this implementation once https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106611 is fixed
-#ifdef _LIBCPP_COMPILER_GCC
-
-template <class _Tp>
-struct _LIBCPP_TEMPLATE_VIS is_nothrow_copy_constructible
-    : public is_nothrow_constructible<_Tp, __add_lvalue_reference_t<const _Tp> > {};
-
-#else // _LIBCPP_COMPILER_GCC
-
 template <class _Tp>
 struct _LIBCPP_TEMPLATE_VIS is_nothrow_copy_constructible
     : public integral_constant< bool, __is_nothrow_constructible(_Tp, __add_lvalue_reference_t<const _Tp>)> {};
 
-#endif // _LIBCPP_COMPILER_GCC
-
 #if _LIBCPP_STD_VER >= 17
 template <class _Tp>
 inline constexpr bool is_nothrow_copy_constructible_v = is_nothrow_copy_constructible<_Tp>::value;
 #endif
 
-// TODO: remove this implementation once https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106611 is fixed
-#ifndef _LIBCPP_COMPILER_GCC
-
 template <class _Tp>
 struct _LIBCPP_TEMPLATE_VIS is_nothrow_move_constructible
     : public integral_constant<bool, __is_nothrow_constructible(_Tp, __add_rvalue_reference_t<_Tp>)> {};
 
-#else // _LIBCPP_COMPILER_GCC
-
-template <class _Tp>
-struct _LIBCPP_TEMPLATE_VIS is_nothrow_move_constructible
-    : public is_nothrow_constructible<_Tp, __add_rvalue_reference_t<_Tp> > {};
-
-#endif // _LIBCPP_COMPILER_GCC
-
 #if _LIBCPP_STD_VER >= 17
 template <class _Tp>
 inline constexpr bool is_nothrow_move_constructible_v = is_nothrow_move_constructible<_Tp>::value;