include/__config - third_party/libcxx - Git at Google

 // -*- C++ -*-
 //===--------------------------- __config ---------------------------------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//

 #ifndef _LIBCPP_CONFIG
 #define _LIBCPP_CONFIG

 #if defined(_MSC_VER) && !defined(__clang__)
 #  if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #    define _LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER
 #  endif
 #endif

 #ifndef _LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER
 #pragma GCC system_header
 #endif

 #ifdef __cplusplus

 #ifdef __GNUC__
 #  define _GNUC_VER (__GNUC__ * 100 + __GNUC_MINOR__)
 // The _GNUC_VER_NEW macro better represents the new GCC versioning scheme
 // introduced in GCC 5.0.
 #  define _GNUC_VER_NEW (_GNUC_VER * 10 + __GNUC_PATCHLEVEL__)
 #else
 #  define _GNUC_VER 0
 #  define _GNUC_VER_NEW 0
 #endif

 #define _LIBCPP_VERSION 10000

 #ifndef _LIBCPP_ABI_VERSION
 #  define _LIBCPP_ABI_VERSION 1
 #endif

 #ifndef __STDC_HOSTED__
 #  define _LIBCPP_FREESTANDING
 #endif

 #ifndef _LIBCPP_STD_VER
 #  if  __cplusplus <= 201103L
 #    define _LIBCPP_STD_VER 11
 #  elif __cplusplus <= 201402L
 #    define _LIBCPP_STD_VER 14
 #  elif __cplusplus <= 201703L
 #    define _LIBCPP_STD_VER 17
 #  else
 #    define _LIBCPP_STD_VER 18  // current year, or date of c++2a ratification
 #  endif
 #endif  // _LIBCPP_STD_VER

 #if defined(__ELF__)
 #  define _LIBCPP_OBJECT_FORMAT_ELF   1
 #elif defined(__MACH__)
 #  define _LIBCPP_OBJECT_FORMAT_MACHO 1
 #elif defined(_WIN32)
 #  define _LIBCPP_OBJECT_FORMAT_COFF  1
 #elif defined(__wasm__)
 #  define _LIBCPP_OBJECT_FORMAT_WASM  1
 #else
 #  error Unknown object file format
 #endif

 #if defined(_LIBCPP_ABI_UNSTABLE) || _LIBCPP_ABI_VERSION >= 2
 // Change short string representation so that string data starts at offset 0,
 // improving its alignment in some cases.
 #  define _LIBCPP_ABI_ALTERNATE_STRING_LAYOUT
 // Fix deque iterator type in order to support incomplete types.
 #  define _LIBCPP_ABI_INCOMPLETE_TYPES_IN_DEQUE
 // Fix undefined behavior in how std::list stores its linked nodes.
 #  define _LIBCPP_ABI_LIST_REMOVE_NODE_POINTER_UB
 // Fix undefined behavior in  how __tree stores its end and parent nodes.
 #  define _LIBCPP_ABI_TREE_REMOVE_NODE_POINTER_UB
 // Fix undefined behavior in how __hash_table stores its pointer types.
 #  define _LIBCPP_ABI_FIX_UNORDERED_NODE_POINTER_UB
 #  define _LIBCPP_ABI_FORWARD_LIST_REMOVE_NODE_POINTER_UB
 #  define _LIBCPP_ABI_FIX_UNORDERED_CONTAINER_SIZE_TYPE
 // Don't use a nullptr_t simulation type in C++03 instead using C++11 nullptr
 // provided under the alternate keyword __nullptr, which changes the mangling
 // of nullptr_t. This option is ABI incompatible with GCC in C++03 mode.
 #  define _LIBCPP_ABI_ALWAYS_USE_CXX11_NULLPTR
 // Define the `pointer_safety` enum as a C++11 strongly typed enumeration
 // instead of as a class simulating an enum. If this option is enabled
 // `pointer_safety` and `get_pointer_safety()` will no longer be available
 // in C++03.
 #  define _LIBCPP_ABI_POINTER_SAFETY_ENUM_TYPE
 // Define a key function for `bad_function_call` in the library, to centralize
 // its vtable and typeinfo to libc++ rather than having all other libraries
 // using that class define their own copies.
 #  define _LIBCPP_ABI_BAD_FUNCTION_CALL_KEY_FUNCTION
 // Enable optimized version of __do_get_(un)signed which avoids redundant copies.
 #  define _LIBCPP_ABI_OPTIMIZED_LOCALE_NUM_GET
 // Use the smallest possible integer type to represent the index of the variant.
 // Previously libc++ used "unsigned int" exclusively.
 #  define _LIBCPP_ABI_VARIANT_INDEX_TYPE_OPTIMIZATION
 // Unstable attempt to provide a more optimized std::function
 #  define _LIBCPP_ABI_OPTIMIZED_FUNCTION
 // All the regex constants must be distinct and nonzero.
 #  define _LIBCPP_ABI_REGEX_CONSTANTS_NONZERO
 #elif _LIBCPP_ABI_VERSION == 1
 #  if !defined(_LIBCPP_OBJECT_FORMAT_COFF)
 // Enable compiling copies of now inline methods into the dylib to support
 // applications compiled against older libraries. This is unnecessary with
 // COFF dllexport semantics, since dllexport forces a non-inline definition
 // of inline functions to be emitted anyway. Our own non-inline copy would
 // conflict with the dllexport-emitted copy, so we disable it.
 #    define _LIBCPP_DEPRECATED_ABI_LEGACY_LIBRARY_DEFINITIONS_FOR_INLINE_FUNCTIONS
 #  endif
 // Feature macros for disabling pre ABI v1 features. All of these options
 // are deprecated.
 #  if defined(__FreeBSD__)
 #    define _LIBCPP_DEPRECATED_ABI_DISABLE_PAIR_TRIVIAL_COPY_CTOR
 #  endif
 #endif

 #ifdef _LIBCPP_TRIVIAL_PAIR_COPY_CTOR
 #error "_LIBCPP_TRIVIAL_PAIR_COPY_CTOR" is no longer supported. \
        use _LIBCPP_DEPRECATED_ABI_DISABLE_PAIR_TRIVIAL_COPY_CTOR instead
 #endif

 #define _LIBCPP_CONCAT1(_LIBCPP_X,_LIBCPP_Y) _LIBCPP_X##_LIBCPP_Y
 #define _LIBCPP_CONCAT(_LIBCPP_X,_LIBCPP_Y) _LIBCPP_CONCAT1(_LIBCPP_X,_LIBCPP_Y)

 #ifndef _LIBCPP_ABI_NAMESPACE
 # define _LIBCPP_ABI_NAMESPACE _LIBCPP_CONCAT(__,_LIBCPP_ABI_VERSION)
 #endif

 #if __cplusplus < 201103L
 #define _LIBCPP_CXX03_LANG
 #endif

 #ifndef __has_attribute
 #define __has_attribute(__x) 0
 #endif

 #ifndef __has_builtin
 #define __has_builtin(__x) 0
 #endif

 #ifndef __has_extension
 #define __has_extension(__x) 0
 #endif

 #ifndef __has_feature
 #define __has_feature(__x) 0
 #endif

 #ifndef __has_cpp_attribute
 #define __has_cpp_attribute(__x) 0
 #endif

 // '__is_identifier' returns '0' if '__x' is a reserved identifier provided by
 // the compiler and '1' otherwise.
 #ifndef __is_identifier
 #define __is_identifier(__x) 1
 #endif

 #ifndef __has_declspec_attribute
 #define __has_declspec_attribute(__x) 0
 #endif

 #define __has_keyword(__x) !(__is_identifier(__x))

 #ifndef __has_include
 #define __has_include(...) 0
 #endif

 #if defined(__clang__)
 #  define _LIBCPP_COMPILER_CLANG
 #  ifndef __apple_build_version__
 #    define _LIBCPP_CLANG_VER (__clang_major__ * 100 + __clang_minor__)
 #  endif
 #elif defined(__GNUC__)
 #  define _LIBCPP_COMPILER_GCC
 #elif defined(_MSC_VER)
 #  define _LIBCPP_COMPILER_MSVC
 #elif defined(__IBMCPP__)
 #  define _LIBCPP_COMPILER_IBM
 #endif

 #if defined(_LIBCPP_COMPILER_GCC) && __cplusplus < 201103L
 #error "libc++ does not support using GCC with C++03. Please enable C++11"
 #endif

 // FIXME: ABI detection should be done via compiler builtin macros. This
 // is just a placeholder until Clang implements such macros. For now assume
 // that Windows compilers pretending to be MSVC++ target the Microsoft ABI,
 // and allow the user to explicitly specify the ABI to handle cases where this
 // heuristic falls short.
 #if defined(_LIBCPP_ABI_FORCE_ITANIUM) && defined(_LIBCPP_ABI_FORCE_MICROSOFT)
 #  error "Only one of _LIBCPP_ABI_FORCE_ITANIUM and _LIBCPP_ABI_FORCE_MICROSOFT can be defined"
 #elif defined(_LIBCPP_ABI_FORCE_ITANIUM)
 #  define _LIBCPP_ABI_ITANIUM
 #elif defined(_LIBCPP_ABI_FORCE_MICROSOFT)
 #  define _LIBCPP_ABI_MICROSOFT
 #else
 #  if defined(_WIN32) && defined(_MSC_VER)
 #    define _LIBCPP_ABI_MICROSOFT
 #  else
 #    define _LIBCPP_ABI_ITANIUM
 #  endif
 #endif

 #if defined(_LIBCPP_ABI_MICROSOFT) && !defined(_LIBCPP_NO_VCRUNTIME)
 # define _LIBCPP_ABI_VCRUNTIME
 #endif

 // Need to detect which libc we're using if we're on Linux.
 #if defined(__linux__)
 #  include <features.h>
 #  if defined(__GLIBC_PREREQ)
 #    define _LIBCPP_GLIBC_PREREQ(a, b) __GLIBC_PREREQ(a, b)
 #  else
 #    define _LIBCPP_GLIBC_PREREQ(a, b) 0
 #  endif // defined(__GLIBC_PREREQ)
 #endif // defined(__linux__)

 #ifdef __LITTLE_ENDIAN__
 #  if __LITTLE_ENDIAN__
 #    define _LIBCPP_LITTLE_ENDIAN
 #  endif  // __LITTLE_ENDIAN__
 #endif  // __LITTLE_ENDIAN__

 #ifdef __BIG_ENDIAN__
 #  if __BIG_ENDIAN__
 #    define _LIBCPP_BIG_ENDIAN
 #  endif  // __BIG_ENDIAN__
 #endif  // __BIG_ENDIAN__

 #ifdef __BYTE_ORDER__
 #  if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
 #    define _LIBCPP_LITTLE_ENDIAN
 #  elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
 #    define _LIBCPP_BIG_ENDIAN
 #  endif // __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
 #endif // __BYTE_ORDER__

 #ifdef __FreeBSD__
 #  include <sys/endian.h>
 #  if _BYTE_ORDER == _LITTLE_ENDIAN
 #    define _LIBCPP_LITTLE_ENDIAN
 #  else  // _BYTE_ORDER == _LITTLE_ENDIAN
 #    define _LIBCPP_BIG_ENDIAN
 #  endif  // _BYTE_ORDER == _LITTLE_ENDIAN
 #  ifndef __LONG_LONG_SUPPORTED
 #    define _LIBCPP_HAS_NO_LONG_LONG
 #  endif  // __LONG_LONG_SUPPORTED
 #endif  // __FreeBSD__

 #ifdef __NetBSD__
 #  include <sys/endian.h>
 #  if _BYTE_ORDER == _LITTLE_ENDIAN
 #    define _LIBCPP_LITTLE_ENDIAN
 #  else  // _BYTE_ORDER == _LITTLE_ENDIAN
 #    define _LIBCPP_BIG_ENDIAN
 #  endif  // _BYTE_ORDER == _LITTLE_ENDIAN
 #  define _LIBCPP_HAS_QUICK_EXIT
 #endif  // __NetBSD__

 #if defined(_WIN32)
 #  define _LIBCPP_WIN32API
 #  define _LIBCPP_LITTLE_ENDIAN
 #  define _LIBCPP_SHORT_WCHAR   1
 // Both MinGW and native MSVC provide a "MSVC"-like environment
 #  define _LIBCPP_MSVCRT_LIKE
 // If mingw not explicitly detected, assume using MS C runtime only if
 // a MS compatibility version is specified.
 #  if defined(_MSC_VER) && !defined(__MINGW32__)
 #    define _LIBCPP_MSVCRT // Using Microsoft's C Runtime library
 #  endif
 #  if (defined(_M_AMD64) || defined(__x86_64__)) || (defined(_M_ARM) || defined(__arm__))
 #    define _LIBCPP_HAS_BITSCAN64
 #  endif
 #  define _LIBCPP_HAS_OPEN_WITH_WCHAR
 #  if defined(_LIBCPP_MSVCRT)
 #    define _LIBCPP_HAS_QUICK_EXIT
 #  endif

 // Some CRT APIs are unavailable to store apps
 #  if defined(WINAPI_FAMILY)
 #    include <winapifamily.h>
 #    if !WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_DESKTOP) &&                  \
         (!defined(WINAPI_PARTITION_SYSTEM) ||                                  \
          !WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_SYSTEM))
 #      define _LIBCPP_WINDOWS_STORE_APP
 #    endif
 #  endif
 #endif // defined(_WIN32)

 #ifdef __sun__
 #  include <sys/isa_defs.h>
 #  ifdef _LITTLE_ENDIAN
 #    define _LIBCPP_LITTLE_ENDIAN
 #  else
 #    define _LIBCPP_BIG_ENDIAN
 #  endif
 #endif // __sun__

 #if defined(__CloudABI__)
    // Certain architectures provide arc4random(). Prefer using
    // arc4random() over /dev/{u,}random to make it possible to obtain
    // random data even when using sandboxing mechanisms such as chroots,
    // Capsicum, etc.
 #  define _LIBCPP_USING_ARC4_RANDOM
 #elif defined(__Fuchsia__) || defined(__wasi__)
 #  define _LIBCPP_USING_GETENTROPY
 #elif defined(__native_client__)
    // NaCl's sandbox (which PNaCl also runs in) doesn't allow filesystem access,
    // including accesses to the special files under /dev. C++11's
    // std::random_device is instead exposed through a NaCl syscall.
 #  define _LIBCPP_USING_NACL_RANDOM
 #elif defined(_LIBCPP_WIN32API)
 #  define _LIBCPP_USING_WIN32_RANDOM
 #else
 #  define _LIBCPP_USING_DEV_RANDOM
 #endif

 #if !defined(_LIBCPP_LITTLE_ENDIAN) && !defined(_LIBCPP_BIG_ENDIAN)
 #  include <endian.h>
 #  if __BYTE_ORDER == __LITTLE_ENDIAN
 #    define _LIBCPP_LITTLE_ENDIAN
 #  elif __BYTE_ORDER == __BIG_ENDIAN
 #    define _LIBCPP_BIG_ENDIAN
 #  else  // __BYTE_ORDER == __BIG_ENDIAN
 #    error unable to determine endian
 #  endif
 #endif  // !defined(_LIBCPP_LITTLE_ENDIAN) && !defined(_LIBCPP_BIG_ENDIAN)

 #if __has_attribute(__no_sanitize__) && !defined(_LIBCPP_COMPILER_GCC)
 #  define _LIBCPP_NO_CFI __attribute__((__no_sanitize__("cfi")))
 #else
 #  define _LIBCPP_NO_CFI
 #endif

 #if __ISO_C_VISIBLE >= 2011 || __cplusplus >= 201103L
 #  if defined(__FreeBSD__)
 #    define _LIBCPP_HAS_QUICK_EXIT
 #    define _LIBCPP_HAS_C11_FEATURES
 #  elif defined(__Fuchsia__) || defined(__wasi__)
 #    define _LIBCPP_HAS_QUICK_EXIT
 #    define _LIBCPP_HAS_TIMESPEC_GET
 #    define _LIBCPP_HAS_C11_FEATURES
 #  elif defined(__linux__)
 #    if !defined(_LIBCPP_HAS_MUSL_LIBC)
 #      if _LIBCPP_GLIBC_PREREQ(2, 15) || defined(__BIONIC__)
 #        define _LIBCPP_HAS_QUICK_EXIT
 #      endif
 #      if _LIBCPP_GLIBC_PREREQ(2, 17)
 #        define _LIBCPP_HAS_C11_FEATURES
 #        define _LIBCPP_HAS_TIMESPEC_GET
 #      endif
 #    else // defined(_LIBCPP_HAS_MUSL_LIBC)
 #      define _LIBCPP_HAS_QUICK_EXIT
 #      define _LIBCPP_HAS_TIMESPEC_GET
 #      define _LIBCPP_HAS_C11_FEATURES
 #    endif
 #  endif // __linux__
 #endif

 #ifndef _LIBCPP_CXX03_LANG
 # define _LIBCPP_ALIGNOF(_Tp) alignof(_Tp)
 #elif defined(_LIBCPP_COMPILER_CLANG)
 # define _LIBCPP_ALIGNOF(_Tp) _Alignof(_Tp)
 #else
 // This definition is potentially buggy, but it's only taken with GCC in C++03,
 // which we barely support anyway. See llvm.org/PR39713
 # define _LIBCPP_ALIGNOF(_Tp) __alignof(_Tp)
 #endif

 #define _LIBCPP_PREFERRED_ALIGNOF(_Tp) __alignof(_Tp)

 #if defined(_LIBCPP_COMPILER_CLANG)

 // _LIBCPP_ALTERNATE_STRING_LAYOUT is an old name for
 // _LIBCPP_ABI_ALTERNATE_STRING_LAYOUT left here for backward compatibility.
 #if (defined(__APPLE__) && !defined(__i386__) && !defined(__x86_64__) &&       \
      (!defined(__arm__) || __ARM_ARCH_7K__ >= 2)) ||                           \
     defined(_LIBCPP_ALTERNATE_STRING_LAYOUT)
 #define _LIBCPP_ABI_ALTERNATE_STRING_LAYOUT
 #endif

 #if __has_feature(cxx_alignas)
 #  define _ALIGNAS_TYPE(x) alignas(x)
 #  define _ALIGNAS(x) alignas(x)
 #else
 #  define _ALIGNAS_TYPE(x) __attribute__((__aligned__(_LIBCPP_ALIGNOF(x))))
 #  define _ALIGNAS(x) __attribute__((__aligned__(x)))
 #endif

 #if __cplusplus < 201103L
 typedef __char16_t char16_t;
 typedef __char32_t char32_t;
 #endif

 #if !(__has_feature(cxx_exceptions)) && !defined(_LIBCPP_NO_EXCEPTIONS)
 #define _LIBCPP_NO_EXCEPTIONS
 #endif

 #if !(__has_feature(cxx_rtti)) && !defined(_LIBCPP_NO_RTTI)
 #define _LIBCPP_NO_RTTI
 #endif

 #if !(__has_feature(cxx_strong_enums))
 #define _LIBCPP_HAS_NO_STRONG_ENUMS
 #endif

 #if __has_feature(cxx_attributes)
 #  define _LIBCPP_NORETURN [[noreturn]]
 #else
 #  define _LIBCPP_NORETURN __attribute__ ((noreturn))
 #endif

 #if !(__has_feature(cxx_lambdas))
 #define _LIBCPP_HAS_NO_LAMBDAS
 #endif

 #if !(__has_feature(cxx_nullptr))
 #  if (__has_extension(cxx_nullptr) || __has_keyword(__nullptr)) && defined(_LIBCPP_ABI_ALWAYS_USE_CXX11_NULLPTR)
 #    define nullptr __nullptr
 #  else
 #    define _LIBCPP_HAS_NO_NULLPTR
 #  endif
 #endif

 #if !(__has_feature(cxx_rvalue_references))
 #define _LIBCPP_HAS_NO_RVALUE_REFERENCES
 #endif

 #if !(__has_feature(cxx_auto_type))
 #define _LIBCPP_HAS_NO_AUTO_TYPE
 #endif

 #if !(__has_feature(cxx_variadic_templates))
 #define _LIBCPP_HAS_NO_VARIADICS
 #endif

 // 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_feature(cxx_relaxed_constexpr))
 #define _LIBCPP_HAS_NO_CXX14_CONSTEXPR
 #endif

 #if !(__has_feature(cxx_variable_templates))
 #define _LIBCPP_HAS_NO_VARIABLE_TEMPLATES
 #endif

 #if !(__has_feature(cxx_noexcept))
 #define _LIBCPP_HAS_NO_NOEXCEPT
 #endif

 #if !defined(_LIBCPP_HAS_NO_ASAN) && !__has_feature(address_sanitizer)
 #define _LIBCPP_HAS_NO_ASAN
 #endif

 // Allow for build-time disabling of unsigned integer sanitization
 #if !defined(_LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK) && __has_attribute(no_sanitize)
 #define _LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK __attribute__((__no_sanitize__("unsigned-integer-overflow")))
 #endif

 #if __has_builtin(__builtin_launder)
 #define _LIBCPP_COMPILER_HAS_BUILTIN_LAUNDER
 #endif

 #if !__is_identifier(__has_unique_object_representations)
 #define _LIBCPP_HAS_UNIQUE_OBJECT_REPRESENTATIONS
 #endif

 #define _LIBCPP_ALWAYS_INLINE __attribute__ ((__always_inline__))

 // Literal operators ""d and ""y are supported starting with LLVM Clang 8 and AppleClang 10.0.1
 #if (defined(_LIBCPP_CLANG_VER) && _LIBCPP_CLANG_VER < 800) || \
     (defined(__apple_build_version__) && __apple_build_version__ < 10010000)
 #define _LIBCPP_HAS_NO_CXX20_CHRONO_LITERALS
 #endif

 #define _LIBCPP_DISABLE_EXTENSION_WARNING __extension__

 #elif defined(_LIBCPP_COMPILER_GCC)

 #define _ALIGNAS(x) __attribute__((__aligned__(x)))
 #define _ALIGNAS_TYPE(x) __attribute__((__aligned__(_LIBCPP_ALIGNOF(x))))

 #define _LIBCPP_NORETURN __attribute__((noreturn))

 #if !__EXCEPTIONS && !defined(_LIBCPP_NO_EXCEPTIONS)
 #define _LIBCPP_NO_EXCEPTIONS
 #endif

 // Determine if GCC supports relaxed constexpr
 #if !defined(__cpp_constexpr) || __cpp_constexpr < 201304L
 #define _LIBCPP_HAS_NO_CXX14_CONSTEXPR
 #endif

 // GCC 5 supports variable templates
 #if !defined(__cpp_variable_templates) || __cpp_variable_templates < 201304L
 #define _LIBCPP_HAS_NO_VARIABLE_TEMPLATES
 #endif

 #if !defined(_LIBCPP_HAS_NO_ASAN) && !defined(__SANITIZE_ADDRESS__)
 #define _LIBCPP_HAS_NO_ASAN
 #endif

 #if _GNUC_VER >= 700
 #define _LIBCPP_COMPILER_HAS_BUILTIN_LAUNDER
 #endif

 #if _GNUC_VER >= 700
 #define _LIBCPP_HAS_UNIQUE_OBJECT_REPRESENTATIONS
 #endif

 #define _LIBCPP_ALWAYS_INLINE __attribute__ ((__always_inline__))

 #define _LIBCPP_DISABLE_EXTENSION_WARNING __extension__

 #elif defined(_LIBCPP_COMPILER_MSVC)

 #define _LIBCPP_TOSTRING2(x) #x
 #define _LIBCPP_TOSTRING(x) _LIBCPP_TOSTRING2(x)
 #define _LIBCPP_WARNING(x) __pragma(message(__FILE__ "(" _LIBCPP_TOSTRING(__LINE__) ") : warning note: " x))

 #if _MSC_VER < 1900
 #error "MSVC versions prior to Visual Studio 2015 are not supported"
 #endif

 #define _LIBCPP_HAS_NO_CXX14_CONSTEXPR
 #define _LIBCPP_HAS_NO_VARIABLE_TEMPLATES
 #define __alignof__ __alignof
 #define _LIBCPP_NORETURN __declspec(noreturn)
 #define _ALIGNAS(x) __declspec(align(x))
 #define _ALIGNAS_TYPE(x) alignas(x)

 #define _LIBCPP_WEAK

 #define _LIBCPP_HAS_NO_ASAN

 #define _LIBCPP_ALWAYS_INLINE __forceinline

 #define _LIBCPP_HAS_NO_VECTOR_EXTENSION

 #define _LIBCPP_DISABLE_EXTENSION_WARNING

 #elif defined(_LIBCPP_COMPILER_IBM)

 #define _ALIGNAS(x) __attribute__((__aligned__(x)))
 #define _ALIGNAS_TYPE(x) __attribute__((__aligned__(_LIBCPP_ALIGNOF(x))))
 #define _ATTRIBUTE(x) __attribute__((x))
 #define _LIBCPP_NORETURN __attribute__((noreturn))

 #define _LIBCPP_HAS_NO_UNICODE_CHARS
 #define _LIBCPP_HAS_NO_VARIABLE_TEMPLATES

 #if defined(_AIX)
 #define __MULTILOCALE_API
 #endif

 #define _LIBCPP_HAS_NO_ASAN

 #define _LIBCPP_ALWAYS_INLINE __attribute__ ((__always_inline__))

 #define _LIBCPP_HAS_NO_VECTOR_EXTENSION

 #define _LIBCPP_DISABLE_EXTENSION_WARNING

 #endif // _LIBCPP_COMPILER_[CLANG|GCC|MSVC|IBM]

 #if defined(_LIBCPP_OBJECT_FORMAT_COFF)

 #ifdef _DLL
 #  define _LIBCPP_CRT_FUNC __declspec(dllimport)
 #else
 #  define _LIBCPP_CRT_FUNC
 #endif

 #if defined(_LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS)
 #  define _LIBCPP_DLL_VIS
 #  define _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS
 #  define _LIBCPP_CLASS_TEMPLATE_INSTANTIATION_VIS
 #  define _LIBCPP_OVERRIDABLE_FUNC_VIS
 #  define _LIBCPP_EXPORTED_FROM_ABI
 #elif defined(_LIBCPP_BUILDING_LIBRARY)
 #  define _LIBCPP_DLL_VIS __declspec(dllexport)
 #  if defined(__MINGW32__)
 #    define _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS _LIBCPP_DLL_VIS
 #    define _LIBCPP_CLASS_TEMPLATE_INSTANTIATION_VIS
 #  else
 #    define _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS
 #    define _LIBCPP_CLASS_TEMPLATE_INSTANTIATION_VIS _LIBCPP_DLL_VIS
 #  endif
 #  define _LIBCPP_OVERRIDABLE_FUNC_VIS _LIBCPP_DLL_VIS
 #  define _LIBCPP_EXPORTED_FROM_ABI __declspec(dllexport)
 #else
 #  define _LIBCPP_DLL_VIS __declspec(dllimport)
 #  define _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS _LIBCPP_DLL_VIS
 #  define _LIBCPP_CLASS_TEMPLATE_INSTANTIATION_VIS
 #  define _LIBCPP_OVERRIDABLE_FUNC_VIS
 #  define _LIBCPP_EXPORTED_FROM_ABI __declspec(dllimport)
 #endif

 #define _LIBCPP_TYPE_VIS            _LIBCPP_DLL_VIS
 #define _LIBCPP_FUNC_VIS            _LIBCPP_DLL_VIS
 #define _LIBCPP_EXCEPTION_ABI       _LIBCPP_DLL_VIS
 #define _LIBCPP_HIDDEN
 #define _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS
 #define _LIBCPP_TEMPLATE_VIS
 #define _LIBCPP_ENUM_VIS

 #endif // defined(_LIBCPP_OBJECT_FORMAT_COFF)

 #ifndef _LIBCPP_HIDDEN
 #  if !defined(_LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS)
 #    define _LIBCPP_HIDDEN __attribute__ ((__visibility__("hidden")))
 #  else
 #    define _LIBCPP_HIDDEN
 #  endif
 #endif

 #ifndef _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS
 #  if !defined(_LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS)
 // The inline should be removed once PR32114 is resolved
 #    define _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS inline _LIBCPP_HIDDEN
 #  else
 #    define _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS
 #  endif
 #endif

 #ifndef _LIBCPP_FUNC_VIS
 #  if !defined(_LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS)
 #    define _LIBCPP_FUNC_VIS __attribute__ ((__visibility__("default")))
 #  else
 #    define _LIBCPP_FUNC_VIS
 #  endif
 #endif

 #ifndef _LIBCPP_TYPE_VIS
 #  if !defined(_LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS)
 #    define _LIBCPP_TYPE_VIS __attribute__ ((__visibility__("default")))
 #  else
 #    define _LIBCPP_TYPE_VIS
 #  endif
 #endif

 #ifndef _LIBCPP_TEMPLATE_VIS
 #  if !defined(_LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS)
 #    if __has_attribute(__type_visibility__)
 #      define _LIBCPP_TEMPLATE_VIS __attribute__ ((__type_visibility__("default")))
 #    else
 #      define _LIBCPP_TEMPLATE_VIS __attribute__ ((__visibility__("default")))
 #    endif
 #  else
 #    define _LIBCPP_TEMPLATE_VIS
 #  endif
 #endif

 #ifndef _LIBCPP_EXPORTED_FROM_ABI
 #  if !defined(_LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS)
 #    define _LIBCPP_EXPORTED_FROM_ABI __attribute__((__visibility__("default")))
 #  else
 #    define _LIBCPP_EXPORTED_FROM_ABI
 #  endif
 #endif

 #ifndef _LIBCPP_OVERRIDABLE_FUNC_VIS
 #define _LIBCPP_OVERRIDABLE_FUNC_VIS _LIBCPP_FUNC_VIS
 #endif

 #ifndef _LIBCPP_EXCEPTION_ABI
 #  if !defined(_LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS)
 #    define _LIBCPP_EXCEPTION_ABI __attribute__ ((__visibility__("default")))
 #  else
 #    define _LIBCPP_EXCEPTION_ABI
 #  endif
 #endif

 #ifndef _LIBCPP_ENUM_VIS
 #  if !defined(_LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS) && __has_attribute(__type_visibility__)
 #    define _LIBCPP_ENUM_VIS __attribute__ ((__type_visibility__("default")))
 #  else
 #    define _LIBCPP_ENUM_VIS
 #  endif
 #endif

 #ifndef _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS
 #  if !defined(_LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS) && __has_attribute(__type_visibility__)
 #    define _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS __attribute__ ((__visibility__("default")))
 #  else
 #    define _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS
 #  endif
 #endif

 #ifndef _LIBCPP_CLASS_TEMPLATE_INSTANTIATION_VIS
 #define _LIBCPP_CLASS_TEMPLATE_INSTANTIATION_VIS
 #endif

 #if __has_attribute(internal_linkage)
 #  define _LIBCPP_INTERNAL_LINKAGE __attribute__ ((internal_linkage))
 #else
 #  define _LIBCPP_INTERNAL_LINKAGE _LIBCPP_ALWAYS_INLINE
 #endif

 #if __has_attribute(exclude_from_explicit_instantiation)
 #  define _LIBCPP_EXCLUDE_FROM_EXPLICIT_INSTANTIATION __attribute__ ((__exclude_from_explicit_instantiation__))
 #else
    // Try to approximate the effect of exclude_from_explicit_instantiation
    // (which is that entities are not assumed to be provided by explicit
    // template instantiations in the dylib) by always inlining those entities.
 #  define _LIBCPP_EXCLUDE_FROM_EXPLICIT_INSTANTIATION _LIBCPP_ALWAYS_INLINE
 #endif

 #ifndef _LIBCPP_HIDE_FROM_ABI_PER_TU
 #  ifndef _LIBCPP_HIDE_FROM_ABI_PER_TU_BY_DEFAULT
 #    define _LIBCPP_HIDE_FROM_ABI_PER_TU 0
 #  else
 #    define _LIBCPP_HIDE_FROM_ABI_PER_TU 1
 #  endif
 #endif

 #ifndef _LIBCPP_HAS_MERGED_TYPEINFO_NAMES_DEFAULT
 # ifdef _LIBCPP_OBJECT_FORMAT_COFF // Windows binaries can't merge typeinfos.
 # define _LIBCPP_HAS_MERGED_TYPEINFO_NAMES_DEFAULT 0
 #else
 // TODO: This isn't strictly correct on ELF platforms due to llvm.org/PR37398
 // And we should consider defaulting to OFF.
 # define _LIBCPP_HAS_MERGED_TYPEINFO_NAMES_DEFAULT 1
 #endif
 #endif

 #ifndef _LIBCPP_HIDE_FROM_ABI
 #  if _LIBCPP_HIDE_FROM_ABI_PER_TU
 #    define _LIBCPP_HIDE_FROM_ABI _LIBCPP_HIDDEN _LIBCPP_INTERNAL_LINKAGE
 #  else
 #    define _LIBCPP_HIDE_FROM_ABI _LIBCPP_HIDDEN _LIBCPP_EXCLUDE_FROM_EXPLICIT_INSTANTIATION
 #  endif
 #endif

 #ifdef _LIBCPP_BUILDING_LIBRARY
 #  if _LIBCPP_ABI_VERSION > 1
 #    define _LIBCPP_HIDE_FROM_ABI_AFTER_V1 _LIBCPP_HIDE_FROM_ABI
 #  else
 #    define _LIBCPP_HIDE_FROM_ABI_AFTER_V1
 #  endif
 #else
 #  define _LIBCPP_HIDE_FROM_ABI_AFTER_V1 _LIBCPP_HIDE_FROM_ABI
 #endif

 // Just so we can migrate to the new macros gradually.
 #define _LIBCPP_INLINE_VISIBILITY _LIBCPP_HIDE_FROM_ABI

 // Inline namespaces are available in Clang/GCC/MSVC regardless of C++ dialect.
 #define _LIBCPP_BEGIN_NAMESPACE_STD namespace std { inline namespace _LIBCPP_ABI_NAMESPACE {
 #define _LIBCPP_END_NAMESPACE_STD  } }
 #define _VSTD std::_LIBCPP_ABI_NAMESPACE
 _LIBCPP_BEGIN_NAMESPACE_STD _LIBCPP_END_NAMESPACE_STD

 #if _LIBCPP_STD_VER >= 17
 #define _LIBCPP_BEGIN_NAMESPACE_FILESYSTEM \
   _LIBCPP_BEGIN_NAMESPACE_STD inline namespace __fs { namespace filesystem {
 #else
 #define _LIBCPP_BEGIN_NAMESPACE_FILESYSTEM \
   _LIBCPP_BEGIN_NAMESPACE_STD namespace __fs { namespace filesystem {
 #endif

 #define _LIBCPP_END_NAMESPACE_FILESYSTEM \
   _LIBCPP_END_NAMESPACE_STD } }

 #define _VSTD_FS _VSTD::__fs::filesystem

 #ifndef _LIBCPP_PREFERRED_OVERLOAD
 #  if __has_attribute(__enable_if__)
 #    define _LIBCPP_PREFERRED_OVERLOAD __attribute__ ((__enable_if__(true, "")))
 #  endif
 #endif

 #ifndef _LIBCPP_HAS_NO_NOEXCEPT
 #  define _NOEXCEPT noexcept
 #  define _NOEXCEPT_(x) noexcept(x)
 #else
 #  define _NOEXCEPT throw()
 #  define _NOEXCEPT_(x)
 #endif

 #ifdef _LIBCPP_HAS_NO_UNICODE_CHARS
 typedef unsigned short char16_t;
 typedef unsigned int   char32_t;
 #endif  // _LIBCPP_HAS_NO_UNICODE_CHARS

 #ifndef __SIZEOF_INT128__
 #define _LIBCPP_HAS_NO_INT128
 #endif

 #ifdef _LIBCPP_CXX03_LANG
 # define static_assert(...) _Static_assert(__VA_ARGS__)
 # define decltype(...) __decltype(__VA_ARGS__)
 #endif  // _LIBCPP_CXX03_LANG

 #ifdef _LIBCPP_CXX03_LANG
 #  define _LIBCPP_CONSTEXPR
 #else
 #  define _LIBCPP_CONSTEXPR constexpr
 #endif

 #ifdef _LIBCPP_CXX03_LANG
 #  define _LIBCPP_DEFAULT {}
 #else
 #  define _LIBCPP_DEFAULT = default;
 #endif

 #ifdef _LIBCPP_CXX03_LANG
 #  define _LIBCPP_EQUAL_DELETE
 #else
 #  define _LIBCPP_EQUAL_DELETE = delete
 #endif

 #ifdef __GNUC__
 #  define _LIBCPP_NOALIAS __attribute__((__malloc__))
 #else
 #  define _LIBCPP_NOALIAS
 #endif

 #if __has_feature(cxx_explicit_conversions) || defined(__IBMCPP__) || \
     (!defined(_LIBCPP_CXX03_LANG) && defined(__GNUC__)) // All supported GCC versions
 #  define _LIBCPP_EXPLICIT explicit
 #else
 #  define _LIBCPP_EXPLICIT
 #endif

 #if !__has_builtin(__builtin_operator_new) || !__has_builtin(__builtin_operator_delete)
 #define _LIBCPP_HAS_NO_BUILTIN_OPERATOR_NEW_DELETE
 #endif

 #ifdef _LIBCPP_HAS_NO_STRONG_ENUMS
 #  define _LIBCPP_DECLARE_STRONG_ENUM(x) struct _LIBCPP_TYPE_VIS x { enum __lx
 #  define _LIBCPP_DECLARE_STRONG_ENUM_EPILOG(x) \
      __lx __v_; \
      _LIBCPP_INLINE_VISIBILITY x(__lx __v) : __v_(__v) {} \
      _LIBCPP_INLINE_VISIBILITY explicit x(int __v) : __v_(static_cast<__lx>(__v)) {} \
      _LIBCPP_INLINE_VISIBILITY operator int() const {return __v_;} \
      };
 #else  // _LIBCPP_HAS_NO_STRONG_ENUMS
 #  define _LIBCPP_DECLARE_STRONG_ENUM(x) enum class _LIBCPP_ENUM_VIS x
 #  define _LIBCPP_DECLARE_STRONG_ENUM_EPILOG(x)
 #endif  // _LIBCPP_HAS_NO_STRONG_ENUMS

 #ifdef _LIBCPP_DEBUG
 #  if _LIBCPP_DEBUG == 0
 #    define _LIBCPP_DEBUG_LEVEL 1
 #  elif _LIBCPP_DEBUG == 1
 #    define _LIBCPP_DEBUG_LEVEL 2
 #  else
 #    error Supported values for _LIBCPP_DEBUG are 0 and 1
 #  endif
 #  if !defined(_LIBCPP_BUILDING_LIBRARY)
 #    define _LIBCPP_EXTERN_TEMPLATE(...)
 #  endif
 #endif

 #ifdef _LIBCPP_DISABLE_EXTERN_TEMPLATE
 #define _LIBCPP_EXTERN_TEMPLATE(...)
 #define _LIBCPP_EXTERN_TEMPLATE2(...)
 #endif

 #ifndef _LIBCPP_EXTERN_TEMPLATE
 #define _LIBCPP_EXTERN_TEMPLATE(...) extern template __VA_ARGS__;
 #endif

 #ifndef _LIBCPP_EXTERN_TEMPLATE2
 #define _LIBCPP_EXTERN_TEMPLATE2(...) extern template __VA_ARGS__;
 #endif

 #if defined(__APPLE__) || defined(__FreeBSD__) || defined(_LIBCPP_MSVCRT_LIKE) || \
     defined(__sun__) || defined(__NetBSD__) || defined(__CloudABI__)
 #define _LIBCPP_LOCALE__L_EXTENSIONS 1
 #endif

 #if defined(__unix__) || (defined(__APPLE__) && defined(__MACH__))
 // Most unix variants have catopen.  These are the specific ones that don't.
 #  if !defined(__BIONIC__) && !defined(_NEWLIB_VERSION)
 #    define _LIBCPP_HAS_CATOPEN 1
 #  endif
 #endif

 #ifdef __FreeBSD__
 #define _DECLARE_C99_LDBL_MATH 1
 #endif

 // If we are getting operator new from the MSVC CRT, then allocation overloads
 // for align_val_t were added in 19.12, aka VS 2017 version 15.3.
 #if defined(_LIBCPP_MSVCRT) && defined(_MSC_VER) && _MSC_VER < 1912
 #  define _LIBCPP_HAS_NO_LIBRARY_ALIGNED_ALLOCATION
 #elif defined(_LIBCPP_ABI_VCRUNTIME) && !defined(__cpp_aligned_new)
    // We're deferring to Microsoft's STL to provide aligned new et al. We don't
    // have it unless the language feature test macro is defined.
 #  define _LIBCPP_HAS_NO_LIBRARY_ALIGNED_ALLOCATION
 #endif

 #if defined(__APPLE__)
 #  if !defined(__MAC_OS_X_VERSION_MIN_REQUIRED) && \
       defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__)
 #    define __MAC_OS_X_VERSION_MIN_REQUIRED __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__
 #  endif
 #endif // defined(__APPLE__)

 #if !defined(_LIBCPP_HAS_NO_ALIGNED_ALLOCATION) && \
     (defined(_LIBCPP_HAS_NO_LIBRARY_ALIGNED_ALLOCATION) || \
     (!defined(__cpp_aligned_new) || __cpp_aligned_new < 201606))
 #  define _LIBCPP_HAS_NO_ALIGNED_ALLOCATION
 #endif

 #if defined(__APPLE__) || defined(__FreeBSD__)
 #define _LIBCPP_HAS_DEFAULTRUNELOCALE
 #endif

 #if defined(__APPLE__) || defined(__FreeBSD__) || defined(__sun__)
 #define _LIBCPP_WCTYPE_IS_MASK
 #endif

 #if _LIBCPP_STD_VER <= 17 || !defined(__cpp_char8_t)
 #define _LIBCPP_NO_HAS_CHAR8_T
 #endif

 // Deprecation macros.
 //
 // Deprecations warnings are always enabled, except when users explicitly opt-out
 // by defining _LIBCPP_DISABLE_DEPRECATION_WARNINGS.
 #if !defined(_LIBCPP_DISABLE_DEPRECATION_WARNINGS)
 #  if __has_attribute(deprecated)
 #    define _LIBCPP_DEPRECATED __attribute__ ((deprecated))
 #  elif _LIBCPP_STD_VER > 11
 #    define _LIBCPP_DEPRECATED [[deprecated]]
 #  else
 #    define _LIBCPP_DEPRECATED
 #  endif
 #else
 #  define _LIBCPP_DEPRECATED
 #endif

 #if !defined(_LIBCPP_CXX03_LANG)
 #  define _LIBCPP_DEPRECATED_IN_CXX11 _LIBCPP_DEPRECATED
 #else
 #  define _LIBCPP_DEPRECATED_IN_CXX11
 #endif

 #if _LIBCPP_STD_VER >= 14
 #  define _LIBCPP_DEPRECATED_IN_CXX14 _LIBCPP_DEPRECATED
 #else
 #  define _LIBCPP_DEPRECATED_IN_CXX14
 #endif

 #if _LIBCPP_STD_VER >= 17
 #  define _LIBCPP_DEPRECATED_IN_CXX17 _LIBCPP_DEPRECATED
 #else
 #  define _LIBCPP_DEPRECATED_IN_CXX17
 #endif

 #if _LIBCPP_STD_VER <= 11
 #  define _LIBCPP_EXPLICIT_AFTER_CXX11
 #else
 #  define _LIBCPP_EXPLICIT_AFTER_CXX11 explicit
 #endif

 #if _LIBCPP_STD_VER > 11 && !defined(_LIBCPP_HAS_NO_CXX14_CONSTEXPR)
 #  define _LIBCPP_CONSTEXPR_AFTER_CXX11 constexpr
 #else
 #  define _LIBCPP_CONSTEXPR_AFTER_CXX11
 #endif

 #if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_CXX14_CONSTEXPR)
 #  define _LIBCPP_CONSTEXPR_AFTER_CXX14 constexpr
 #else
 #  define _LIBCPP_CONSTEXPR_AFTER_CXX14
 #endif

 #if _LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_CXX14_CONSTEXPR)
 #  define _LIBCPP_CONSTEXPR_AFTER_CXX17 constexpr
 #else
 #  define _LIBCPP_CONSTEXPR_AFTER_CXX17
 #endif

 // The _LIBCPP_NODISCARD_ATTRIBUTE should only be used to define other
 // NODISCARD macros to the correct attribute.
 #if __has_cpp_attribute(nodiscard) || defined(_LIBCPP_COMPILER_MSVC)
 #  define _LIBCPP_NODISCARD_ATTRIBUTE [[nodiscard]]
 #elif defined(_LIBCPP_COMPILER_CLANG) && !defined(_LIBCPP_CXX03_LANG)
 #  define _LIBCPP_NODISCARD_ATTRIBUTE [[clang::warn_unused_result]]
 #else
 // We can't use GCC's [[gnu::warn_unused_result]] and
 // __attribute__((warn_unused_result)), because GCC does not silence them via
 // (void) cast.
 #  define _LIBCPP_NODISCARD_ATTRIBUTE
 #endif

 // _LIBCPP_NODISCARD_EXT may be used to apply [[nodiscard]] to entities not
 // specified as such as an extension.
 #if defined(_LIBCPP_ENABLE_NODISCARD) && !defined(_LIBCPP_DISABLE_NODISCARD_EXT)
 #  define _LIBCPP_NODISCARD_EXT _LIBCPP_NODISCARD_ATTRIBUTE
 #else
 #  define _LIBCPP_NODISCARD_EXT
 #endif

 #if !defined(_LIBCPP_DISABLE_NODISCARD_AFTER_CXX17) && \
     (_LIBCPP_STD_VER > 17 || defined(_LIBCPP_ENABLE_NODISCARD))
 #  define _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_NODISCARD_ATTRIBUTE
 #else
 #  define _LIBCPP_NODISCARD_AFTER_CXX17
 #endif

 #if _LIBCPP_STD_VER > 14 && defined(__cpp_inline_variables) && (__cpp_inline_variables >= 201606L)
 #  define _LIBCPP_INLINE_VAR inline
 #else
 #  define _LIBCPP_INLINE_VAR
 #endif

 #ifdef _LIBCPP_HAS_NO_RVALUE_REFERENCES
 #  define _LIBCPP_EXPLICIT_MOVE(x) _VSTD::move(x)
 #else
 #  define _LIBCPP_EXPLICIT_MOVE(x) (x)
 #endif

 #ifndef _LIBCPP_CONSTEXPR_IF_NODEBUG
 #if defined(_LIBCPP_DEBUG) || defined(_LIBCPP_HAS_NO_CXX14_CONSTEXPR)
 #define _LIBCPP_CONSTEXPR_IF_NODEBUG
 #else
 #define _LIBCPP_CONSTEXPR_IF_NODEBUG constexpr
 #endif
 #endif

 #if __has_attribute(no_destroy)
 #  define _LIBCPP_NO_DESTROY __attribute__((__no_destroy__))
 #else
 #  define _LIBCPP_NO_DESTROY
 #endif

 #ifndef _LIBCPP_HAS_NO_ASAN
 _LIBCPP_FUNC_VIS extern "C" void __sanitizer_annotate_contiguous_container(
   const void *, const void *, const void *, const void *);
 #endif

 // Try to find out if RTTI is disabled.
 // g++ and cl.exe have RTTI on by default and define a macro when it is.
 // g++ only defines the macro in 4.3.2 and onwards.
 #if !defined(_LIBCPP_NO_RTTI)
 #  if defined(__GNUC__) && \
       ((__GNUC__ >= 5) || \
        (__GNUC__ == 4 && (__GNUC_MINOR__ >= 3 || __GNUC_PATCHLEVEL__ >= 2))) && \
       !defined(__GXX_RTTI)
 #    define _LIBCPP_NO_RTTI
 #  elif defined(_LIBCPP_COMPILER_MSVC) && !defined(_CPPRTTI)
 #    define _LIBCPP_NO_RTTI
 #  endif
 #endif

 #ifndef _LIBCPP_WEAK
 #define _LIBCPP_WEAK __attribute__((__weak__))
 #endif

 // Thread API
 #if !defined(_LIBCPP_HAS_NO_THREADS) && \
     !defined(_LIBCPP_HAS_THREAD_API_PTHREAD) && \
     !defined(_LIBCPP_HAS_THREAD_API_WIN32) && \
     !defined(_LIBCPP_HAS_THREAD_API_EXTERNAL)
 #  if defined(__FreeBSD__) || \
       defined(__Fuchsia__) || \
       defined(__wasi__) || \
       defined(__NetBSD__) || \
       defined(__linux__) || \
       defined(__GNU__) || \
       defined(__APPLE__) || \
       defined(__CloudABI__) || \
       defined(__sun__) || \
       (defined(__MINGW32__) && __has_include(<pthread.h>))
 #    define _LIBCPP_HAS_THREAD_API_PTHREAD
 #  elif defined(_LIBCPP_WIN32API)
 #    define _LIBCPP_HAS_THREAD_API_WIN32
 #  else
 #    error "No thread API"
 #  endif // _LIBCPP_HAS_THREAD_API
 #endif // _LIBCPP_HAS_NO_THREADS

 #if defined(_LIBCPP_HAS_THREAD_API_PTHREAD)
 #if defined(__ANDROID__) && __ANDROID_API__ >= 30
 #define _LIBCPP_HAS_COND_CLOCKWAIT
 #elif defined(_LIBCPP_GLIBC_PREREQ)
 #if _LIBCPP_GLIBC_PREREQ(2, 30)
 #define _LIBCPP_HAS_COND_CLOCKWAIT
 #endif
 #endif
 #endif

 #if defined(_LIBCPP_HAS_NO_THREADS) && defined(_LIBCPP_HAS_THREAD_API_PTHREAD)
 #error _LIBCPP_HAS_THREAD_API_PTHREAD may only be defined when \
        _LIBCPP_HAS_NO_THREADS is not defined.
 #endif

 #if defined(_LIBCPP_HAS_NO_THREADS) && defined(_LIBCPP_HAS_THREAD_API_EXTERNAL)
 #error _LIBCPP_HAS_THREAD_API_EXTERNAL may not be defined when \
        _LIBCPP_HAS_NO_THREADS is defined.
 #endif

 #if defined(_LIBCPP_HAS_NO_MONOTONIC_CLOCK) && !defined(_LIBCPP_HAS_NO_THREADS)
 #error _LIBCPP_HAS_NO_MONOTONIC_CLOCK may only be defined when \
        _LIBCPP_HAS_NO_THREADS is defined.
 #endif

 #if defined(__STDCPP_THREADS__) && defined(_LIBCPP_HAS_NO_THREADS)
 #error _LIBCPP_HAS_NO_THREADS cannot be set when __STDCPP_THREADS__ is set.
 #endif

 #if !defined(_LIBCPP_HAS_NO_THREADS) && !defined(__STDCPP_THREADS__)
 #define __STDCPP_THREADS__ 1
 #endif

 // The glibc and Bionic implementation of pthreads implements
 // pthread_mutex_destroy as nop for regular mutexes. Additionally, Win32
 // mutexes have no destroy mechanism.
 //
 // This optimization can't be performed on Apple platforms, where
 // pthread_mutex_destroy can allow the kernel to release resources.
 // See https://llvm.org/D64298 for details.
 //
 // TODO(EricWF): Enable this optimization on Bionic after speaking to their
 //               respective stakeholders.
 #if (defined(_LIBCPP_HAS_THREAD_API_PTHREAD) && defined(__GLIBC__)) \
   || defined(_LIBCPP_HAS_THREAD_API_WIN32)
 # define _LIBCPP_HAS_TRIVIAL_MUTEX_DESTRUCTION
 #endif

 // Destroying a condvar is a nop on Windows.
 //
 // This optimization can't be performed on Apple platforms, where
 // pthread_cond_destroy can allow the kernel to release resources.
 // See https://llvm.org/D64298 for details.
 //
 // TODO(EricWF): This is potentially true for some pthread implementations
 // as well.
 #if defined(_LIBCPP_HAS_THREAD_API_WIN32)
 # define _LIBCPP_HAS_TRIVIAL_CONDVAR_DESTRUCTION
 #endif

 // Systems that use capability-based security (FreeBSD with Capsicum,
 // Nuxi CloudABI) may only provide local filesystem access (using *at()).
 // Functions like open(), rename(), unlink() and stat() should not be
 // used, as they attempt to access the global filesystem namespace.
 #ifdef __CloudABI__
 #define _LIBCPP_HAS_NO_GLOBAL_FILESYSTEM_NAMESPACE
 #endif

 // CloudABI is intended for running networked services. Processes do not
 // have standard input and output channels.
 #ifdef __CloudABI__
 #define _LIBCPP_HAS_NO_STDIN
 #define _LIBCPP_HAS_NO_STDOUT
 #endif

 // Some systems do not provide gets() in their C library, for security reasons.
 #ifndef _LIBCPP_C_HAS_NO_GETS
 #  if defined(_LIBCPP_MSVCRT) || (defined(__FreeBSD__) && __FreeBSD__ >= 13)
 #    define _LIBCPP_C_HAS_NO_GETS
 #  endif
 #endif

 #if defined(__BIONIC__) || defined(__CloudABI__) ||                            \
     defined(__Fuchsia__) || defined(__wasi__) || defined(_LIBCPP_HAS_MUSL_LIBC)
 #define _LIBCPP_PROVIDES_DEFAULT_RUNE_TABLE
 #endif

 // Thread-unsafe functions such as strtok() and localtime()
 // are not available.
 #ifdef __CloudABI__
 #define _LIBCPP_HAS_NO_THREAD_UNSAFE_C_FUNCTIONS
 #endif

 #if __has_feature(cxx_atomic) || __has_extension(c_atomic) || __has_keyword(_Atomic)
 #  define _LIBCPP_HAS_C_ATOMIC_IMP
 #elif defined(_LIBCPP_COMPILER_GCC)
 #  define _LIBCPP_HAS_GCC_ATOMIC_IMP
 #endif

 #if (!defined(_LIBCPP_HAS_C_ATOMIC_IMP) && \
      !defined(_LIBCPP_HAS_GCC_ATOMIC_IMP) && \
      !defined(_LIBCPP_HAS_EXTERNAL_ATOMIC_IMP)) \
      || defined(_LIBCPP_HAS_NO_THREADS)
 #  define _LIBCPP_HAS_NO_ATOMIC_HEADER
 #else
 #  ifndef _LIBCPP_ATOMIC_FLAG_TYPE
 #    define _LIBCPP_ATOMIC_FLAG_TYPE bool
 #  endif
 #  ifdef _LIBCPP_FREESTANDING
 #    define _LIBCPP_ATOMIC_ONLY_USE_BUILTINS
 #  endif
 #endif

 #ifndef _LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK
 #define _LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK
 #endif

 #if defined(_LIBCPP_ENABLE_THREAD_SAFETY_ANNOTATIONS)
 #  if defined(__clang__) && __has_attribute(acquire_capability)
 // Work around the attribute handling in clang.  When both __declspec and
 // __attribute__ are present, the processing goes awry preventing the definition
 // of the types.
 #    if !defined(_LIBCPP_OBJECT_FORMAT_COFF)
 #      define _LIBCPP_HAS_THREAD_SAFETY_ANNOTATIONS
 #    endif
 #  endif
 #endif

 #if __has_attribute(require_constant_initialization)
 #  define _LIBCPP_SAFE_STATIC __attribute__((__require_constant_initialization__))
 #else
 #  define _LIBCPP_SAFE_STATIC
 #endif

 #if !__has_builtin(__builtin_addressof) && _GNUC_VER < 700
 #define _LIBCPP_HAS_NO_BUILTIN_ADDRESSOF
 #endif

 #if !__has_builtin(__builtin_is_constant_evaluated) && _GNUC_VER < 900
 #define _LIBCPP_HAS_NO_BUILTIN_IS_CONSTANT_EVALUATED
 #endif

 #if !defined(_LIBCPP_HAS_NO_OFF_T_FUNCTIONS)
 #  if defined(_LIBCPP_MSVCRT) || defined(_NEWLIB_VERSION)
 #    define _LIBCPP_HAS_NO_OFF_T_FUNCTIONS
 #  endif
 #endif

 #if __has_attribute(diagnose_if) && !defined(_LIBCPP_DISABLE_ADDITIONAL_DIAGNOSTICS)
 #  define _LIBCPP_DIAGNOSE_WARNING(...) \
      __attribute__((diagnose_if(__VA_ARGS__, "warning")))
 #  define _LIBCPP_DIAGNOSE_ERROR(...) \
      __attribute__((diagnose_if(__VA_ARGS__, "error")))
 #else
 #  define _LIBCPP_DIAGNOSE_WARNING(...)
 #  define _LIBCPP_DIAGNOSE_ERROR(...)
 #endif

 // Use a function like macro to imply that it must be followed by a semicolon
 #if __cplusplus > 201402L && __has_cpp_attribute(fallthrough)
 #  define _LIBCPP_FALLTHROUGH() [[fallthrough]]
 #elif __has_cpp_attribute(clang::fallthrough)
 #  define _LIBCPP_FALLTHROUGH() [[clang::fallthrough]]
 #elif __has_attribute(fallthough) || _GNUC_VER >= 700
 #  define _LIBCPP_FALLTHROUGH() __attribute__((__fallthrough__))
 #else
 #  define _LIBCPP_FALLTHROUGH() ((void)0)
 #endif

 #if __has_attribute(__nodebug__)
 #define _LIBCPP_NODEBUG __attribute__((__nodebug__))
 #else
 #define _LIBCPP_NODEBUG
 #endif

 #ifndef _LIBCPP_NODEBUG_TYPE
 #if __has_attribute(__nodebug__) && \
     (defined(_LIBCPP_CLANG_VER) && _LIBCPP_CLANG_VER >= 900)
 #define _LIBCPP_NODEBUG_TYPE __attribute__((nodebug))
 #else
 #define _LIBCPP_NODEBUG_TYPE
 #endif
 #endif // !defined(_LIBCPP_NODEBUG_TYPE)

 #if defined(_LIBCPP_ABI_MICROSOFT) && \
     (defined(_LIBCPP_COMPILER_MSVC) || __has_declspec_attribute(empty_bases))
 #  define _LIBCPP_DECLSPEC_EMPTY_BASES __declspec(empty_bases)
 #else
 #  define _LIBCPP_DECLSPEC_EMPTY_BASES
 #endif

 #if defined(_LIBCPP_ENABLE_CXX17_REMOVED_FEATURES)
 #define _LIBCPP_ENABLE_CXX17_REMOVED_AUTO_PTR
 #define _LIBCPP_ENABLE_CXX17_REMOVED_UNEXPECTED_FUNCTIONS
 #define _LIBCPP_ENABLE_CXX17_REMOVED_RANDOM_SHUFFLE
 #define _LIBCPP_ENABLE_CXX17_REMOVED_BINDERS
 #endif // _LIBCPP_ENABLE_CXX17_REMOVED_FEATURES

 #if !defined(__cpp_deduction_guides) || __cpp_deduction_guides < 201611
 #define _LIBCPP_HAS_NO_DEDUCTION_GUIDES
 #endif

 #if !__has_keyword(__is_aggregate) && (_GNUC_VER_NEW < 7001)
 #define _LIBCPP_HAS_NO_IS_AGGREGATE
 #endif

 #if !defined(__cpp_coroutines) || __cpp_coroutines < 201703L
 #define _LIBCPP_HAS_NO_COROUTINES
 #endif

 // FIXME: Correct this macro when either (A) a feature test macro for the
 // spaceship operator is provided, or (B) a compiler provides a complete
 // implementation.
 #define _LIBCPP_HAS_NO_SPACESHIP_OPERATOR

 // Decide whether to use availability macros.
 #if !defined(_LIBCPP_BUILDING_LIBRARY) &&                                      \
     !defined(_LIBCPP_DISABLE_AVAILABILITY) &&                                  \
     __has_feature(attribute_availability_with_strict) &&                       \
     __has_feature(attribute_availability_in_templates) &&                      \
     __has_extension(pragma_clang_attribute_external_declaration)
 #  ifdef __APPLE__
 #    define _LIBCPP_USE_AVAILABILITY_APPLE
 #  endif
 #endif

 // Define availability macros.
 #if defined(_LIBCPP_USE_AVAILABILITY_APPLE)
 #  define _LIBCPP_AVAILABILITY_SHARED_MUTEX                                    \
      __attribute__((availability(macosx,strict,introduced=10.12)))             \
      __attribute__((availability(ios,strict,introduced=10.0)))                 \
      __attribute__((availability(tvos,strict,introduced=10.0)))                \
      __attribute__((availability(watchos,strict,introduced=3.0)))
 #  define _LIBCPP_AVAILABILITY_BAD_OPTIONAL_ACCESS                             \
      __attribute__((availability(macosx,strict,introduced=10.14)))             \
      __attribute__((availability(ios,strict,introduced=12.0)))                 \
      __attribute__((availability(tvos,strict,introduced=12.0)))                \
      __attribute__((availability(watchos,strict,introduced=5.0)))
 #  define _LIBCPP_AVAILABILITY_BAD_VARIANT_ACCESS                              \
      _LIBCPP_AVAILABILITY_BAD_OPTIONAL_ACCESS
 #  define _LIBCPP_AVAILABILITY_BAD_ANY_CAST                                    \
      _LIBCPP_AVAILABILITY_BAD_OPTIONAL_ACCESS
 #  define _LIBCPP_AVAILABILITY_UNCAUGHT_EXCEPTIONS                             \
      __attribute__((availability(macosx,strict,introduced=10.12)))             \
      __attribute__((availability(ios,strict,introduced=10.0)))                 \
      __attribute__((availability(tvos,strict,introduced=10.0)))                \
      __attribute__((availability(watchos,strict,introduced=3.0)))
 #  define _LIBCPP_AVAILABILITY_SIZED_NEW_DELETE                                \
      __attribute__((availability(macosx,strict,introduced=10.12)))             \
      __attribute__((availability(ios,strict,introduced=10.0)))                 \
      __attribute__((availability(tvos,strict,introduced=10.0)))                \
      __attribute__((availability(watchos,strict,introduced=3.0)))
 #  define _LIBCPP_AVAILABILITY_FUTURE_ERROR                                    \
      __attribute__((availability(ios,strict,introduced=6.0)))
 #  define _LIBCPP_AVAILABILITY_TYPEINFO_VTABLE                                 \
      __attribute__((availability(macosx,strict,introduced=10.9)))              \
      __attribute__((availability(ios,strict,introduced=7.0)))
 #  define _LIBCPP_AVAILABILITY_LOCALE_CATEGORY                                 \
      __attribute__((availability(macosx,strict,introduced=10.9)))              \
      __attribute__((availability(ios,strict,introduced=7.0)))
 #  define _LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR                               \
      __attribute__((availability(macosx,strict,introduced=10.9)))              \
      __attribute__((availability(ios,strict,introduced=7.0)))
 #  define _LIBCPP_AVAILABILITY_FILESYSTEM                                      \
      __attribute__((availability(macosx,strict,introduced=10.15)))             \
      __attribute__((availability(ios,strict,introduced=13.0)))                 \
      __attribute__((availability(tvos,strict,introduced=13.0)))                \
      __attribute__((availability(watchos,strict,introduced=6.0)))
 #  define _LIBCPP_AVAILABILITY_FILESYSTEM_PUSH                                 \
      _Pragma("clang attribute push(__attribute__((availability(macosx,strict,introduced=10.15))), apply_to=any(function,record))") \
      _Pragma("clang attribute push(__attribute__((availability(ios,strict,introduced=13.0))), apply_to=any(function,record))")     \
      _Pragma("clang attribute push(__attribute__((availability(tvos,strict,introduced=13.0))), apply_to=any(function,record))")    \
      _Pragma("clang attribute push(__attribute__((availability(watchos,strict,introduced=6.0))), apply_to=any(function,record))")
 #  define _LIBCPP_AVAILABILITY_FILESYSTEM_POP                                  \
      _Pragma("clang attribute pop")                                            \
      _Pragma("clang attribute pop")                                            \
      _Pragma("clang attribute pop")                                            \
      _Pragma("clang attribute pop")
 #else
 #  define _LIBCPP_AVAILABILITY_SHARED_MUTEX
 #  define _LIBCPP_AVAILABILITY_BAD_VARIANT_ACCESS
 #  define _LIBCPP_AVAILABILITY_BAD_OPTIONAL_ACCESS
 #  define _LIBCPP_AVAILABILITY_BAD_ANY_CAST
 #  define _LIBCPP_AVAILABILITY_UNCAUGHT_EXCEPTIONS
 #  define _LIBCPP_AVAILABILITY_SIZED_NEW_DELETE
 #  define _LIBCPP_AVAILABILITY_FUTURE_ERROR
 #  define _LIBCPP_AVAILABILITY_TYPEINFO_VTABLE
 #  define _LIBCPP_AVAILABILITY_LOCALE_CATEGORY
 #  define _LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR
 #  define _LIBCPP_AVAILABILITY_FILESYSTEM
 #  define _LIBCPP_AVAILABILITY_FILESYSTEM_PUSH
 #  define _LIBCPP_AVAILABILITY_FILESYSTEM_POP
 #endif

 // Define availability that depends on _LIBCPP_NO_EXCEPTIONS.
 #ifdef _LIBCPP_NO_EXCEPTIONS
 #  define _LIBCPP_AVAILABILITY_FUTURE
 #  define _LIBCPP_AVAILABILITY_THROW_BAD_ANY_CAST
 #  define _LIBCPP_AVAILABILITY_THROW_BAD_OPTIONAL_ACCESS
 #  define _LIBCPP_AVAILABILITY_THROW_BAD_VARIANT_ACCESS
 #else
 #  define _LIBCPP_AVAILABILITY_FUTURE                    _LIBCPP_AVAILABILITY_FUTURE_ERROR
 #  define _LIBCPP_AVAILABILITY_THROW_BAD_ANY_CAST        _LIBCPP_AVAILABILITY_BAD_ANY_CAST
 #  define _LIBCPP_AVAILABILITY_THROW_BAD_OPTIONAL_ACCESS _LIBCPP_AVAILABILITY_BAD_OPTIONAL_ACCESS
 #  define _LIBCPP_AVAILABILITY_THROW_BAD_VARIANT_ACCESS  _LIBCPP_AVAILABILITY_BAD_VARIANT_ACCESS
 #endif

 // The stream API was dropped and re-added in the dylib shipped on macOS
 // and iOS. We can only assume the dylib to provide these definitions for
 // macosx >= 10.9 and ios >= 7.0. Otherwise, the definitions are available
 // from the headers, but not from the dylib. Explicit instantiation
 // declarations for streams exist conditionally to this; if we provide
 // an explicit instantiation declaration and we try to deploy to a dylib
 // that does not provide those symbols, we'll get a load-time error.
 #if !defined(_LIBCPP_BUILDING_LIBRARY) &&                                      \
     ((defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) &&                \
       __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ < 1090) ||                 \
      (defined(__ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__) &&               \
       __ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__ < 70000))
 #  define _LIBCPP_DO_NOT_ASSUME_STREAMS_EXPLICIT_INSTANTIATION_IN_DYLIB
 #endif

 #if defined(_LIBCPP_COMPILER_IBM)
 #define _LIBCPP_HAS_NO_PRAGMA_PUSH_POP_MACRO
 #endif

 #if defined(_LIBCPP_HAS_NO_PRAGMA_PUSH_POP_MACRO)
 #  define _LIBCPP_PUSH_MACROS
 #  define _LIBCPP_POP_MACROS
 #else
   // Don't warn about macro conflicts when we can restore them at the
   // end of the header.
 #  ifndef _LIBCPP_DISABLE_MACRO_CONFLICT_WARNINGS
 #    define _LIBCPP_DISABLE_MACRO_CONFLICT_WARNINGS
 #  endif
 #  if defined(_LIBCPP_COMPILER_MSVC)
 #    define _LIBCPP_PUSH_MACROS    \
        __pragma(push_macro("min")) \
        __pragma(push_macro("max"))
 #    define _LIBCPP_POP_MACROS     \
        __pragma(pop_macro("min"))  \
        __pragma(pop_macro("max"))
 #  else
 #    define _LIBCPP_PUSH_MACROS        \
        _Pragma("push_macro(\"min\")")  \
        _Pragma("push_macro(\"max\")")
 #    define _LIBCPP_POP_MACROS         \
        _Pragma("pop_macro(\"min\")")   \
        _Pragma("pop_macro(\"max\")")
 #  endif
 #endif // defined(_LIBCPP_HAS_NO_PRAGMA_PUSH_POP_MACRO)

 #ifndef _LIBCPP_NO_AUTO_LINK
 #  if defined(_LIBCPP_ABI_MICROSOFT) && !defined(_LIBCPP_BUILDING_LIBRARY)
 #    if defined(_DLL)
 #      pragma comment(lib, "c++.lib")
 #    else
 #      pragma comment(lib, "libc++.lib")
 #    endif
 #  endif // defined(_LIBCPP_ABI_MICROSOFT) && !defined(_LIBCPP_BUILDING_LIBRARY)
 #endif // _LIBCPP_NO_AUTO_LINK

 #define _LIBCPP_UNUSED_VAR(x) ((void)(x))

 // Configures the fopen close-on-exec mode character, if any. This string will
 // be appended to any mode string used by fstream for fopen/fdopen.
 //
 // Not all platforms support this, but it helps avoid fd-leaks on platforms that
 // do.
 #if defined(__BIONIC__)
 #  define _LIBCPP_FOPEN_CLOEXEC_MODE "e"
 #else
 #  define _LIBCPP_FOPEN_CLOEXEC_MODE
 #endif

 #endif // __cplusplus

 #endif // _LIBCPP_CONFIG