lib: establish Zircon libc++ and KTL foundation

11 files changed, 1392 insertions, 0 deletions

diff --git a/third_party/libcxx/include/c++/v1/__charconv/chars_format.h b/third_party/libcxx/include/c++/v1/__charconv/chars_format.h
new file mode 100644
index 0000000..c76cebd
--- /dev/null
+++ b/third_party/libcxx/include/c++/v1/__charconv/chars_format.h
@@ -0,0 +1,61 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// 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___CHARCONV_CHARS_FORMAT_H
+#define _LIBCPP___CHARCONV_CHARS_FORMAT_H
+
+#include <__config>
+#include <__utility/to_underlying.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#  pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+
+enum class chars_format { scientific = 0x1, fixed = 0x2, hex = 0x4, general = fixed | scientific };
+
+inline _LIBCPP_HIDE_FROM_ABI constexpr chars_format operator~(chars_format __x) {
+  return chars_format(~std::__to_underlying(__x));
+}
+
+inline _LIBCPP_HIDE_FROM_ABI constexpr chars_format operator&(chars_format __x, chars_format __y) {
+  return chars_format(std::__to_underlying(__x) & std::__to_underlying(__y));
+}
+
+inline _LIBCPP_HIDE_FROM_ABI constexpr chars_format operator|(chars_format __x, chars_format __y) {
+  return chars_format(std::__to_underlying(__x) | std::__to_underlying(__y));
+}
+
+inline _LIBCPP_HIDE_FROM_ABI constexpr chars_format operator^(chars_format __x, chars_format __y) {
+  return chars_format(std::__to_underlying(__x) ^ std::__to_underlying(__y));
+}
+
+inline _LIBCPP_HIDE_FROM_ABI constexpr chars_format& operator&=(chars_format& __x, chars_format __y) {
+  __x = __x & __y;
+  return __x;
+}
+
+inline _LIBCPP_HIDE_FROM_ABI constexpr chars_format& operator|=(chars_format& __x, chars_format __y) {
+  __x = __x | __y;
+  return __x;
+}
+
+inline _LIBCPP_HIDE_FROM_ABI constexpr chars_format& operator^=(chars_format& __x, chars_format __y) {
+  __x = __x ^ __y;
+  return __x;
+}
+
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___CHARCONV_CHARS_FORMAT_H
diff --git a/third_party/libcxx/include/c++/v1/__charconv/from_chars_floating_point.h b/third_party/libcxx/include/c++/v1/__charconv/from_chars_floating_point.h
new file mode 100644
index 0000000..811e518
--- /dev/null
+++ b/third_party/libcxx/include/c++/v1/__charconv/from_chars_floating_point.h
@@ -0,0 +1,73 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// 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___CHARCONV_FROM_CHARS_FLOATING_POINT_H
+#define _LIBCPP___CHARCONV_FROM_CHARS_FLOATING_POINT_H
+
+#include <__assert>
+#include <__charconv/chars_format.h>
+#include <__charconv/from_chars_result.h>
+#include <__config>
+#include <__cstddef/ptrdiff_t.h>
+#include <__system_error/errc.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#  pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+
+template <class _Fp>
+struct __from_chars_result {
+  _Fp __value;
+  ptrdiff_t __n;
+  errc __ec;
+};
+
+template <class _Fp>
+_LIBCPP_EXPORTED_FROM_ABI __from_chars_result<_Fp> __from_chars_floating_point(
+    _LIBCPP_NOESCAPE const char* __first, _LIBCPP_NOESCAPE const char* __last, chars_format __fmt);
+
+extern template __from_chars_result<float> __from_chars_floating_point(
+    _LIBCPP_NOESCAPE const char* __first, _LIBCPP_NOESCAPE const char* __last, chars_format __fmt);
+
+extern template __from_chars_result<double> __from_chars_floating_point(
+    _LIBCPP_NOESCAPE const char* __first, _LIBCPP_NOESCAPE const char* __last, chars_format __fmt);
+
+template <class _Fp>
+_LIBCPP_HIDE_FROM_ABI from_chars_result
+__from_chars(const char* __first, const char* __last, _Fp& __value, chars_format __fmt) {
+  __from_chars_result<_Fp> __r = std::__from_chars_floating_point<_Fp>(__first, __last, __fmt);
+  if (__r.__ec != errc::invalid_argument)
+    __value = __r.__value;
+  return {__first + __r.__n, __r.__ec};
+}
+
+_LIBCPP_AVAILABILITY_FROM_CHARS_FLOATING_POINT _LIBCPP_HIDE_FROM_ABI inline from_chars_result
+from_chars(const char* __first, const char* __last, float& __value, chars_format __fmt = chars_format::general) {
+  return std::__from_chars<float>(__first, __last, __value, __fmt);
+}
+
+_LIBCPP_AVAILABILITY_FROM_CHARS_FLOATING_POINT _LIBCPP_HIDE_FROM_ABI inline from_chars_result
+from_chars(const char* __first, const char* __last, double& __value, chars_format __fmt = chars_format::general) {
+  return std::__from_chars<double>(__first, __last, __value, __fmt);
+}
+
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___CHARCONV_FROM_CHARS_FLOATING_POINT_H
diff --git a/third_party/libcxx/include/c++/v1/__charconv/from_chars_integral.h b/third_party/libcxx/include/c++/v1/__charconv/from_chars_integral.h
new file mode 100644
index 0000000..3063c09
--- /dev/null
+++ b/third_party/libcxx/include/c++/v1/__charconv/from_chars_integral.h
@@ -0,0 +1,237 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// 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___CHARCONV_FROM_CHARS_INTEGRAL_H
+#define _LIBCPP___CHARCONV_FROM_CHARS_INTEGRAL_H
+
+#include <__assert>
+#include <__charconv/from_chars_result.h>
+#include <__charconv/traits.h>
+#include <__config>
+#include <__system_error/errc.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_integral.h>
+#include <__type_traits/is_signed.h>
+#include <__type_traits/is_unsigned.h>
+#include <__type_traits/make_unsigned.h>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#  pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+
+from_chars_result from_chars(const char*, const char*, bool, int = 10) = delete;
+
+template <typename _It, typename _Tp, typename _Fn, typename... _Ts>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI from_chars_result
+__sign_combinator(_It __first, _It __last, _Tp& __value, _Fn __f, _Ts... __args) {
+  using __tl = numeric_limits<_Tp>;
+  decltype(std::__to_unsigned_like(__value)) __x;
+
+  bool __neg = (__first != __last && *__first == '-');
+  auto __r   = __f(__neg ? __first + 1 : __first, __last, __x, __args...);
+  switch (__r.ec) {
+  case errc::invalid_argument:
+    return {__first, __r.ec};
+  case errc::result_out_of_range:
+    return __r;
+  default:
+    break;
+  }
+
+  if (__neg) {
+    if (__x <= std::__complement(std::__to_unsigned_like(__tl::min()))) {
+      __value = std::__complement(__x);
+      return __r;
+    }
+  } else {
+    if (__x <= std::__to_unsigned_like(__tl::max())) {
+      __value = __x;
+      return __r;
+    }
+  }
+
+  return {__r.ptr, errc::result_out_of_range};
+}
+
+template <typename _Tp>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI bool __in_pattern(_Tp __c) {
+  return '0' <= __c && __c <= '9';
+}
+
+struct _LIBCPP_HIDDEN __in_pattern_result {
+  bool __ok;
+  int __val;
+
+  explicit _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI operator bool() const { return __ok; }
+};
+
+template <typename _Tp>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI __in_pattern_result __in_pattern(_Tp __c, int __base) {
+  if (__base <= 10)
+    return {'0' <= __c && __c < '0' + __base, __c - '0'};
+  else if (std::__in_pattern(__c))
+    return {true, __c - '0'};
+  else if ('a' <= __c && __c < 'a' + __base - 10)
+    return {true, __c - 'a' + 10};
+  else
+    return {'A' <= __c && __c < 'A' + __base - 10, __c - 'A' + 10};
+}
+
+template <typename _It, typename _Tp, typename _Fn, typename... _Ts>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI from_chars_result
+__subject_seq_combinator(_It __first, _It __last, _Tp& __value, _Fn __f, _Ts... __args) {
+  auto __find_non_zero = [](_It __firstit, _It __lastit) {
+    for (; __firstit != __lastit; ++__firstit)
+      if (*__firstit != '0')
+        break;
+    return __firstit;
+  };
+
+  auto __p = __find_non_zero(__first, __last);
+  if (__p == __last || !std::__in_pattern(*__p, __args...)) {
+    if (__p == __first)
+      return {__first, errc::invalid_argument};
+    else {
+      __value = 0;
+      return {__p, {}};
+    }
+  }
+
+  auto __r = __f(__p, __last, __value, __args...);
+  if (__r.ec == errc::result_out_of_range) {
+    for (; __r.ptr != __last; ++__r.ptr) {
+      if (!std::__in_pattern(*__r.ptr, __args...))
+        break;
+    }
+  }
+
+  return __r;
+}
+
+template <typename _Tp, __enable_if_t<is_unsigned<_Tp>::value, int> = 0>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI from_chars_result
+__from_chars_atoi(const char* __first, const char* __last, _Tp& __value) {
+  using __tx          = __itoa::__traits<_Tp>;
+  using __output_type = typename __tx::type;
+
+  return std::__subject_seq_combinator(
+      __first, __last, __value, [](const char* __f, const char* __l, _Tp& __val) -> from_chars_result {
+        __output_type __a, __b;
+        auto __p = __tx::__read(__f, __l, __a, __b);
+        if (__p == __l || !std::__in_pattern(*__p)) {
+          __output_type __m = numeric_limits<_Tp>::max();
+          if (__m >= __a && __m - __a >= __b) {
+            __val = __a + __b;
+            return {__p, {}};
+          }
+        }
+        return {__p, errc::result_out_of_range};
+      });
+}
+
+template <typename _Tp, __enable_if_t<is_signed<_Tp>::value, int> = 0>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI from_chars_result
+__from_chars_atoi(const char* __first, const char* __last, _Tp& __value) {
+  using __t = decltype(std::__to_unsigned_like(__value));
+  return std::__sign_combinator(__first, __last, __value, __from_chars_atoi<__t>);
+}
+
+/*
+// Code used to generate __from_chars_log2f_lut.
+#include <cmath>
+#include <format>
+#include <iostream>
+
+int main() {
+  for (int i = 2; i <= 36; ++i)
+    std::cout << std::format("{},\n", log2f(i));
+}
+*/
+/// log2f table for bases [2, 36].
+inline constexpr float __from_chars_log2f_lut[35] = {
+    1,         1.5849625, 2,         2.321928, 2.5849626, 2.807355, 3,        3.169925,  3.321928,
+    3.4594316, 3.5849626, 3.7004397, 3.807355, 3.9068906, 4,        4.087463, 4.169925,  4.2479277,
+    4.321928,  4.3923173, 4.4594316, 4.523562, 4.5849624, 4.643856, 4.70044,  4.7548876, 4.807355,
+    4.857981,  4.9068904, 4.9541965, 5,        5.044394,  5.087463, 5.129283, 5.169925};
+
+template <typename _Tp, __enable_if_t<is_unsigned<_Tp>::value, int> = 0>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI from_chars_result
+__from_chars_integral(const char* __first, const char* __last, _Tp& __value, int __base) {
+  if (__base == 10)
+    return std::__from_chars_atoi(__first, __last, __value);
+
+  return std::__subject_seq_combinator(
+      __first,
+      __last,
+      __value,
+      [](const char* __p, const char* __lastp, _Tp& __val, int __b) -> from_chars_result {
+        using __tl = numeric_limits<_Tp>;
+        // __base is always between 2 and 36 inclusive.
+        auto __digits = __tl::digits / __from_chars_log2f_lut[__b - 2];
+        _Tp __x = __in_pattern(*__p++, __b).__val, __y = 0;
+
+        for (int __i = 1; __p != __lastp; ++__i, ++__p) {
+          if (auto __c = __in_pattern(*__p, __b)) {
+            if (__i < __digits - 1)
+              __x = __x * __b + __c.__val;
+            else {
+              if (!__itoa::__mul_overflowed(__x, __b, __x))
+                ++__p;
+              __y = __c.__val;
+              break;
+            }
+          } else
+            break;
+        }
+
+        if (__p == __lastp || !__in_pattern(*__p, __b)) {
+          if (__tl::max() - __x >= __y) {
+            __val = __x + __y;
+            return {__p, {}};
+          }
+        }
+        return {__p, errc::result_out_of_range};
+      },
+      __base);
+}
+
+template <typename _Tp, __enable_if_t<is_signed<_Tp>::value, int> = 0>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI from_chars_result
+__from_chars_integral(const char* __first, const char* __last, _Tp& __value, int __base) {
+  using __t = decltype(std::__to_unsigned_like(__value));
+  return std::__sign_combinator(__first, __last, __value, __from_chars_integral<__t>, __base);
+}
+
+template <typename _Tp, __enable_if_t<is_integral<_Tp>::value, int> = 0>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI from_chars_result
+from_chars(const char* __first, const char* __last, _Tp& __value) {
+  return std::__from_chars_atoi(__first, __last, __value);
+}
+
+template <typename _Tp, __enable_if_t<is_integral<_Tp>::value, int> = 0>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI from_chars_result
+from_chars(const char* __first, const char* __last, _Tp& __value, int __base) {
+  _LIBCPP_ASSERT_UNCATEGORIZED(2 <= __base && __base <= 36, "base not in [2, 36]");
+  return std::__from_chars_integral(__first, __last, __value, __base);
+}
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___CHARCONV_FROM_CHARS_INTEGRAL_H
diff --git a/third_party/libcxx/include/c++/v1/__charconv/from_chars_result.h b/third_party/libcxx/include/c++/v1/__charconv/from_chars_result.h
new file mode 100644
index 0000000..b4ecea3
--- /dev/null
+++ b/third_party/libcxx/include/c++/v1/__charconv/from_chars_result.h
@@ -0,0 +1,39 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// 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___CHARCONV_FROM_CHARS_RESULT_H
+#define _LIBCPP___CHARCONV_FROM_CHARS_RESULT_H
+
+#include <__config>
+#include <__system_error/errc.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#  pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+
+struct from_chars_result {
+  const char* ptr;
+  errc ec;
+#  if _LIBCPP_STD_VER >= 20
+  _LIBCPP_HIDE_FROM_ABI friend bool operator==(const from_chars_result&, const from_chars_result&) = default;
+#  endif
+#  if _LIBCPP_STD_VER >= 26
+  _LIBCPP_HIDE_FROM_ABI constexpr explicit operator bool() const noexcept { return ec == errc{}; }
+#  endif
+};
+
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___CHARCONV_FROM_CHARS_RESULT_H
diff --git a/third_party/libcxx/include/c++/v1/__charconv/tables.h b/third_party/libcxx/include/c++/v1/__charconv/tables.h
new file mode 100644
index 0000000..b8c6fd8
--- /dev/null
+++ b/third_party/libcxx/include/c++/v1/__charconv/tables.h
@@ -0,0 +1,159 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// 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___CHARCONV_TABLES
+#define _LIBCPP___CHARCONV_TABLES
+
+#include <__config>
+#include <cstdint>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#  pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace __itoa {
+
+inline _LIBCPP_CONSTEXPR const char __base_2_lut[64] = {
+    '0', '0', '0', '0', '0', '0', '0', '1', '0', '0', '1', '0', '0', '0', '1', '1', '0', '1', '0', '0', '0', '1',
+    '0', '1', '0', '1', '1', '0', '0', '1', '1', '1', '1', '0', '0', '0', '1', '0', '0', '1', '1', '0', '1', '0',
+    '1', '0', '1', '1', '1', '1', '0', '0', '1', '1', '0', '1', '1', '1', '1', '0', '1', '1', '1', '1'};
+
+inline _LIBCPP_CONSTEXPR const char __base_8_lut[128] = {
+    '0', '0', '0', '1', '0', '2', '0', '3', '0', '4', '0', '5', '0', '6', '0', '7', '1', '0', '1', '1', '1', '2',
+    '1', '3', '1', '4', '1', '5', '1', '6', '1', '7', '2', '0', '2', '1', '2', '2', '2', '3', '2', '4', '2', '5',
+    '2', '6', '2', '7', '3', '0', '3', '1', '3', '2', '3', '3', '3', '4', '3', '5', '3', '6', '3', '7', '4', '0',
+    '4', '1', '4', '2', '4', '3', '4', '4', '4', '5', '4', '6', '4', '7', '5', '0', '5', '1', '5', '2', '5', '3',
+    '5', '4', '5', '5', '5', '6', '5', '7', '6', '0', '6', '1', '6', '2', '6', '3', '6', '4', '6', '5', '6', '6',
+    '6', '7', '7', '0', '7', '1', '7', '2', '7', '3', '7', '4', '7', '5', '7', '6', '7', '7'};
+
+inline _LIBCPP_CONSTEXPR const char __base_16_lut[512] = {
+    '0', '0', '0', '1', '0', '2', '0', '3', '0', '4', '0', '5', '0', '6', '0', '7', '0', '8', '0', '9', '0', 'a', '0',
+    'b', '0', 'c', '0', 'd', '0', 'e', '0', 'f', '1', '0', '1', '1', '1', '2', '1', '3', '1', '4', '1', '5', '1', '6',
+    '1', '7', '1', '8', '1', '9', '1', 'a', '1', 'b', '1', 'c', '1', 'd', '1', 'e', '1', 'f', '2', '0', '2', '1', '2',
+    '2', '2', '3', '2', '4', '2', '5', '2', '6', '2', '7', '2', '8', '2', '9', '2', 'a', '2', 'b', '2', 'c', '2', 'd',
+    '2', 'e', '2', 'f', '3', '0', '3', '1', '3', '2', '3', '3', '3', '4', '3', '5', '3', '6', '3', '7', '3', '8', '3',
+    '9', '3', 'a', '3', 'b', '3', 'c', '3', 'd', '3', 'e', '3', 'f', '4', '0', '4', '1', '4', '2', '4', '3', '4', '4',
+    '4', '5', '4', '6', '4', '7', '4', '8', '4', '9', '4', 'a', '4', 'b', '4', 'c', '4', 'd', '4', 'e', '4', 'f', '5',
+    '0', '5', '1', '5', '2', '5', '3', '5', '4', '5', '5', '5', '6', '5', '7', '5', '8', '5', '9', '5', 'a', '5', 'b',
+    '5', 'c', '5', 'd', '5', 'e', '5', 'f', '6', '0', '6', '1', '6', '2', '6', '3', '6', '4', '6', '5', '6', '6', '6',
+    '7', '6', '8', '6', '9', '6', 'a', '6', 'b', '6', 'c', '6', 'd', '6', 'e', '6', 'f', '7', '0', '7', '1', '7', '2',
+    '7', '3', '7', '4', '7', '5', '7', '6', '7', '7', '7', '8', '7', '9', '7', 'a', '7', 'b', '7', 'c', '7', 'd', '7',
+    'e', '7', 'f', '8', '0', '8', '1', '8', '2', '8', '3', '8', '4', '8', '5', '8', '6', '8', '7', '8', '8', '8', '9',
+    '8', 'a', '8', 'b', '8', 'c', '8', 'd', '8', 'e', '8', 'f', '9', '0', '9', '1', '9', '2', '9', '3', '9', '4', '9',
+    '5', '9', '6', '9', '7', '9', '8', '9', '9', '9', 'a', '9', 'b', '9', 'c', '9', 'd', '9', 'e', '9', 'f', 'a', '0',
+    'a', '1', 'a', '2', 'a', '3', 'a', '4', 'a', '5', 'a', '6', 'a', '7', 'a', '8', 'a', '9', 'a', 'a', 'a', 'b', 'a',
+    'c', 'a', 'd', 'a', 'e', 'a', 'f', 'b', '0', 'b', '1', 'b', '2', 'b', '3', 'b', '4', 'b', '5', 'b', '6', 'b', '7',
+    'b', '8', 'b', '9', 'b', 'a', 'b', 'b', 'b', 'c', 'b', 'd', 'b', 'e', 'b', 'f', 'c', '0', 'c', '1', 'c', '2', 'c',
+    '3', 'c', '4', 'c', '5', 'c', '6', 'c', '7', 'c', '8', 'c', '9', 'c', 'a', 'c', 'b', 'c', 'c', 'c', 'd', 'c', 'e',
+    'c', 'f', 'd', '0', 'd', '1', 'd', '2', 'd', '3', 'd', '4', 'd', '5', 'd', '6', 'd', '7', 'd', '8', 'd', '9', 'd',
+    'a', 'd', 'b', 'd', 'c', 'd', 'd', 'd', 'e', 'd', 'f', 'e', '0', 'e', '1', 'e', '2', 'e', '3', 'e', '4', 'e', '5',
+    'e', '6', 'e', '7', 'e', '8', 'e', '9', 'e', 'a', 'e', 'b', 'e', 'c', 'e', 'd', 'e', 'e', 'e', 'f', 'f', '0', 'f',
+    '1', 'f', '2', 'f', '3', 'f', '4', 'f', '5', 'f', '6', 'f', '7', 'f', '8', 'f', '9', 'f', 'a', 'f', 'b', 'f', 'c',
+    'f', 'd', 'f', 'e', 'f', 'f'};
+
+inline _LIBCPP_CONSTEXPR const uint32_t __pow10_32[10] = {
+    UINT32_C(0),
+    UINT32_C(10),
+    UINT32_C(100),
+    UINT32_C(1000),
+    UINT32_C(10000),
+    UINT32_C(100000),
+    UINT32_C(1000000),
+    UINT32_C(10000000),
+    UINT32_C(100000000),
+    UINT32_C(1000000000)};
+
+inline _LIBCPP_CONSTEXPR const uint64_t __pow10_64[20] = {
+    UINT64_C(0),
+    UINT64_C(10),
+    UINT64_C(100),
+    UINT64_C(1000),
+    UINT64_C(10000),
+    UINT64_C(100000),
+    UINT64_C(1000000),
+    UINT64_C(10000000),
+    UINT64_C(100000000),
+    UINT64_C(1000000000),
+    UINT64_C(10000000000),
+    UINT64_C(100000000000),
+    UINT64_C(1000000000000),
+    UINT64_C(10000000000000),
+    UINT64_C(100000000000000),
+    UINT64_C(1000000000000000),
+    UINT64_C(10000000000000000),
+    UINT64_C(100000000000000000),
+    UINT64_C(1000000000000000000),
+    UINT64_C(10000000000000000000)};
+
+#  if _LIBCPP_HAS_INT128
+inline _LIBCPP_CONSTEXPR const int __pow10_128_offset      = 0;
+inline _LIBCPP_CONSTEXPR const __uint128_t __pow10_128[40] = {
+    UINT64_C(0),
+    UINT64_C(10),
+    UINT64_C(100),
+    UINT64_C(1000),
+    UINT64_C(10000),
+    UINT64_C(100000),
+    UINT64_C(1000000),
+    UINT64_C(10000000),
+    UINT64_C(100000000),
+    UINT64_C(1000000000),
+    UINT64_C(10000000000),
+    UINT64_C(100000000000),
+    UINT64_C(1000000000000),
+    UINT64_C(10000000000000),
+    UINT64_C(100000000000000),
+    UINT64_C(1000000000000000),
+    UINT64_C(10000000000000000),
+    UINT64_C(100000000000000000),
+    UINT64_C(1000000000000000000),
+    UINT64_C(10000000000000000000),
+    __uint128_t(UINT64_C(10000000000000000000)) * UINT64_C(10),
+    __uint128_t(UINT64_C(10000000000000000000)) * UINT64_C(100),
+    __uint128_t(UINT64_C(10000000000000000000)) * UINT64_C(1000),
+    __uint128_t(UINT64_C(10000000000000000000)) * UINT64_C(10000),
+    __uint128_t(UINT64_C(10000000000000000000)) * UINT64_C(100000),
+    __uint128_t(UINT64_C(10000000000000000000)) * UINT64_C(1000000),
+    __uint128_t(UINT64_C(10000000000000000000)) * UINT64_C(10000000),
+    __uint128_t(UINT64_C(10000000000000000000)) * UINT64_C(100000000),
+    __uint128_t(UINT64_C(10000000000000000000)) * UINT64_C(1000000000),
+    __uint128_t(UINT64_C(10000000000000000000)) * UINT64_C(10000000000),
+    __uint128_t(UINT64_C(10000000000000000000)) * UINT64_C(100000000000),
+    __uint128_t(UINT64_C(10000000000000000000)) * UINT64_C(1000000000000),
+    __uint128_t(UINT64_C(10000000000000000000)) * UINT64_C(10000000000000),
+    __uint128_t(UINT64_C(10000000000000000000)) * UINT64_C(100000000000000),
+    __uint128_t(UINT64_C(10000000000000000000)) * UINT64_C(1000000000000000),
+    __uint128_t(UINT64_C(10000000000000000000)) * UINT64_C(10000000000000000),
+    __uint128_t(UINT64_C(10000000000000000000)) * UINT64_C(100000000000000000),
+    __uint128_t(UINT64_C(10000000000000000000)) * UINT64_C(1000000000000000000),
+    __uint128_t(UINT64_C(10000000000000000000)) * UINT64_C(10000000000000000000),
+    (__uint128_t(UINT64_C(10000000000000000000)) * UINT64_C(10000000000000000000)) * 10};
+#  endif
+
+inline _LIBCPP_CONSTEXPR const char __digits_base_10[200] = {
+    // clang-format off
+    '0', '0', '0', '1', '0', '2', '0', '3', '0', '4', '0', '5', '0', '6', '0', '7', '0', '8', '0', '9',
+    '1', '0', '1', '1', '1', '2', '1', '3', '1', '4', '1', '5', '1', '6', '1', '7', '1', '8', '1', '9',
+    '2', '0', '2', '1', '2', '2', '2', '3', '2', '4', '2', '5', '2', '6', '2', '7', '2', '8', '2', '9',
+    '3', '0', '3', '1', '3', '2', '3', '3', '3', '4', '3', '5', '3', '6', '3', '7', '3', '8', '3', '9',
+    '4', '0', '4', '1', '4', '2', '4', '3', '4', '4', '4', '5', '4', '6', '4', '7', '4', '8', '4', '9',
+    '5', '0', '5', '1', '5', '2', '5', '3', '5', '4', '5', '5', '5', '6', '5', '7', '5', '8', '5', '9',
+    '6', '0', '6', '1', '6', '2', '6', '3', '6', '4', '6', '5', '6', '6', '6', '7', '6', '8', '6', '9',
+    '7', '0', '7', '1', '7', '2', '7', '3', '7', '4', '7', '5', '7', '6', '7', '7', '7', '8', '7', '9',
+    '8', '0', '8', '1', '8', '2', '8', '3', '8', '4', '8', '5', '8', '6', '8', '7', '8', '8', '8', '9',
+    '9', '0', '9', '1', '9', '2', '9', '3', '9', '4', '9', '5', '9', '6', '9', '7', '9', '8', '9', '9'};
+// clang-format on
+
+} // namespace __itoa
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___CHARCONV_TABLES
diff --git a/third_party/libcxx/include/c++/v1/__charconv/to_chars.h b/third_party/libcxx/include/c++/v1/__charconv/to_chars.h
new file mode 100644
index 0000000..8ef09af
--- /dev/null
+++ b/third_party/libcxx/include/c++/v1/__charconv/to_chars.h
@@ -0,0 +1,25 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// 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___CHARCONV_TO_CHARS
+#define _LIBCPP___CHARCONV_TO_CHARS
+
+#include <__charconv/to_chars_floating_point.h>
+#include <__charconv/to_chars_integral.h>
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#  pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___CHARCONV_TO_CHARS
diff --git a/third_party/libcxx/include/c++/v1/__charconv/to_chars_base_10.h b/third_party/libcxx/include/c++/v1/__charconv/to_chars_base_10.h
new file mode 100644
index 0000000..d90952e
--- /dev/null
+++ b/third_party/libcxx/include/c++/v1/__charconv/to_chars_base_10.h
@@ -0,0 +1,184 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// 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___CHARCONV_TO_CHARS_BASE_10_H
+#define _LIBCPP___CHARCONV_TO_CHARS_BASE_10_H
+
+#include <__algorithm/copy_n.h>
+#include <__assert>
+#include <__charconv/tables.h>
+#include <__config>
+#include <cstdint>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#  pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace __itoa {
+
+_LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI inline char* __append1(char* __first, uint32_t __value) _NOEXCEPT {
+  *__first = '0' + static_cast<char>(__value);
+  return __first + 1;
+}
+
+_LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI inline char* __append2(char* __first, uint32_t __value) _NOEXCEPT {
+  return std::copy_n(&__digits_base_10[__value * 2], 2, __first);
+}
+
+_LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI inline char* __append3(char* __first, uint32_t __value) _NOEXCEPT {
+  return __itoa::__append2(__itoa::__append1(__first, __value / 100), __value % 100);
+}
+
+_LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI inline char* __append4(char* __first, uint32_t __value) _NOEXCEPT {
+  return __itoa::__append2(__itoa::__append2(__first, __value / 100), __value % 100);
+}
+
+_LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI inline char* __append5(char* __first, uint32_t __value) _NOEXCEPT {
+  return __itoa::__append4(__itoa::__append1(__first, __value / 10000), __value % 10000);
+}
+
+_LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI inline char* __append6(char* __first, uint32_t __value) _NOEXCEPT {
+  return __itoa::__append4(__itoa::__append2(__first, __value / 10000), __value % 10000);
+}
+
+_LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI inline char* __append7(char* __first, uint32_t __value) _NOEXCEPT {
+  return __itoa::__append6(__itoa::__append1(__first, __value / 1000000), __value % 1000000);
+}
+
+_LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI inline char* __append8(char* __first, uint32_t __value) _NOEXCEPT {
+  return __itoa::__append6(__itoa::__append2(__first, __value / 1000000), __value % 1000000);
+}
+
+_LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI inline char* __append9(char* __first, uint32_t __value) _NOEXCEPT {
+  return __itoa::__append8(__itoa::__append1(__first, __value / 100000000), __value % 100000000);
+}
+
+template <class _Tp>
+_LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI char* __append10(char* __first, _Tp __value) _NOEXCEPT {
+  return __itoa::__append8(__itoa::__append2(__first, static_cast<uint32_t>(__value / 100000000)),
+                           static_cast<uint32_t>(__value % 100000000));
+}
+
+_LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI inline char*
+__base_10_u32(char* __first, uint32_t __value) _NOEXCEPT {
+  if (__value < 1000000) {
+    if (__value < 10000) {
+      if (__value < 100) {
+        // 0 <= __value < 100
+        if (__value < 10)
+          return __itoa::__append1(__first, __value);
+        return __itoa::__append2(__first, __value);
+      }
+      // 100 <= __value < 10'000
+      if (__value < 1000)
+        return __itoa::__append3(__first, __value);
+      return __itoa::__append4(__first, __value);
+    }
+
+    // 10'000 <= __value < 1'000'000
+    if (__value < 100000)
+      return __itoa::__append5(__first, __value);
+    return __itoa::__append6(__first, __value);
+  }
+
+  // __value => 1'000'000
+  if (__value < 100000000) {
+    // 1'000'000 <= __value < 100'000'000
+    if (__value < 10000000)
+      return __itoa::__append7(__first, __value);
+    return __itoa::__append8(__first, __value);
+  }
+
+  // 100'000'000 <= __value < max
+  if (__value < 1000000000)
+    return __itoa::__append9(__first, __value);
+  return __itoa::__append10(__first, __value);
+}
+
+_LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI inline char*
+__base_10_u64(char* __buffer, uint64_t __value) _NOEXCEPT {
+  if (__value <= UINT32_MAX)
+    return __itoa::__base_10_u32(__buffer, static_cast<uint32_t>(__value));
+
+  // Numbers in the range UINT32_MAX <= val < 10'000'000'000 always contain 10
+  // digits and are outputted after this if statement.
+  if (__value >= 10000000000) {
+    // This function properly deterimines the first non-zero leading digit.
+    __buffer = __itoa::__base_10_u32(__buffer, static_cast<uint32_t>(__value / 10000000000));
+    __value %= 10000000000;
+  }
+  return __itoa::__append10(__buffer, __value);
+}
+
+#  if _LIBCPP_HAS_INT128
+/// \returns 10^\a exp
+///
+/// \pre \a exp [19, 39]
+///
+/// \note The lookup table contains a partial set of exponents limiting the
+/// range that can be used. However the range is sufficient for
+/// \ref __base_10_u128.
+_LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI inline __uint128_t __pow_10(int __exp) _NOEXCEPT {
+  _LIBCPP_ASSERT_INTERNAL(__exp >= __pow10_128_offset, "Index out of bounds");
+  return __pow10_128[__exp - __pow10_128_offset];
+}
+
+_LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI inline char*
+__base_10_u128(char* __buffer, __uint128_t __value) _NOEXCEPT {
+  _LIBCPP_ASSERT_INTERNAL(
+      __value > numeric_limits<uint64_t>::max(), "The optimizations for this algorithm fails when this isn't true.");
+
+  // Unlike the 64 to 32 bit case the 128 bit case the "upper half" can't be
+  // stored in the "lower half". Instead we first need to handle the top most
+  // digits separately.
+  //
+  // Maximum unsigned values
+  // 64  bit                             18'446'744'073'709'551'615 (20 digits)
+  // 128 bit    340'282'366'920'938'463'463'374'607'431'768'211'455 (39 digits)
+  // step 1     ^                                                   ([0-1] digits)
+  // step 2      ^^^^^^^^^^^^^^^^^^^^^^^^^                          ([0-19] digits)
+  // step 3                               ^^^^^^^^^^^^^^^^^^^^^^^^^ (19 digits)
+  if (__value >= __itoa::__pow_10(38)) {
+    // step 1
+    __buffer = __itoa::__append1(__buffer, static_cast<uint32_t>(__value / __itoa::__pow_10(38)));
+    __value %= __itoa::__pow_10(38);
+
+    // step 2 always 19 digits.
+    // They are handled here since leading zeros need to be appended to the buffer,
+    __buffer = __itoa::__append9(__buffer, static_cast<uint32_t>(__value / __itoa::__pow_10(29)));
+    __value %= __itoa::__pow_10(29);
+    __buffer = __itoa::__append10(__buffer, static_cast<uint64_t>(__value / __itoa::__pow_10(19)));
+    __value %= __itoa::__pow_10(19);
+  } else {
+    // step 2
+    // This version needs to determine the position of the leading non-zero digit.
+    __buffer = __base_10_u64(__buffer, static_cast<uint64_t>(__value / __itoa::__pow_10(19)));
+    __value %= __itoa::__pow_10(19);
+  }
+
+  // Step 3
+  __buffer = __itoa::__append9(__buffer, static_cast<uint32_t>(__value / 10000000000));
+  __buffer = __itoa::__append10(__buffer, static_cast<uint64_t>(__value % 10000000000));
+
+  return __buffer;
+}
+#  endif
+} // namespace __itoa
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___CHARCONV_TO_CHARS_BASE_10_H
diff --git a/third_party/libcxx/include/c++/v1/__charconv/to_chars_floating_point.h b/third_party/libcxx/include/c++/v1/__charconv/to_chars_floating_point.h
new file mode 100644
index 0000000..118f316
--- /dev/null
+++ b/third_party/libcxx/include/c++/v1/__charconv/to_chars_floating_point.h
@@ -0,0 +1,55 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// 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___CHARCONV_TO_CHARS_FLOATING_POINT_H
+#define _LIBCPP___CHARCONV_TO_CHARS_FLOATING_POINT_H
+
+#include <__charconv/chars_format.h>
+#include <__charconv/to_chars_result.h>
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#  pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+
+_LIBCPP_AVAILABILITY_TO_CHARS_FLOATING_POINT _LIBCPP_EXPORTED_FROM_ABI to_chars_result
+to_chars(char* __first, char* __last, float __value);
+
+_LIBCPP_AVAILABILITY_TO_CHARS_FLOATING_POINT _LIBCPP_EXPORTED_FROM_ABI to_chars_result
+to_chars(char* __first, char* __last, double __value);
+
+_LIBCPP_AVAILABILITY_TO_CHARS_FLOATING_POINT _LIBCPP_EXPORTED_FROM_ABI to_chars_result
+to_chars(char* __first, char* __last, long double __value);
+
+_LIBCPP_AVAILABILITY_TO_CHARS_FLOATING_POINT _LIBCPP_EXPORTED_FROM_ABI to_chars_result
+to_chars(char* __first, char* __last, float __value, chars_format __fmt);
+
+_LIBCPP_AVAILABILITY_TO_CHARS_FLOATING_POINT _LIBCPP_EXPORTED_FROM_ABI to_chars_result
+to_chars(char* __first, char* __last, double __value, chars_format __fmt);
+
+_LIBCPP_AVAILABILITY_TO_CHARS_FLOATING_POINT _LIBCPP_EXPORTED_FROM_ABI to_chars_result
+to_chars(char* __first, char* __last, long double __value, chars_format __fmt);
+
+_LIBCPP_AVAILABILITY_TO_CHARS_FLOATING_POINT _LIBCPP_EXPORTED_FROM_ABI to_chars_result
+to_chars(char* __first, char* __last, float __value, chars_format __fmt, int __precision);
+
+_LIBCPP_AVAILABILITY_TO_CHARS_FLOATING_POINT _LIBCPP_EXPORTED_FROM_ABI to_chars_result
+to_chars(char* __first, char* __last, double __value, chars_format __fmt, int __precision);
+
+_LIBCPP_AVAILABILITY_TO_CHARS_FLOATING_POINT _LIBCPP_EXPORTED_FROM_ABI to_chars_result
+to_chars(char* __first, char* __last, long double __value, chars_format __fmt, int __precision);
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___CHARCONV_TO_CHARS_FLOATING_POINT_H
diff --git a/third_party/libcxx/include/c++/v1/__charconv/to_chars_integral.h b/third_party/libcxx/include/c++/v1/__charconv/to_chars_integral.h
new file mode 100644
index 0000000..6d42513
--- /dev/null
+++ b/third_party/libcxx/include/c++/v1/__charconv/to_chars_integral.h
@@ -0,0 +1,344 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// 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___CHARCONV_TO_CHARS_INTEGRAL_H
+#define _LIBCPP___CHARCONV_TO_CHARS_INTEGRAL_H
+
+#include <__algorithm/copy_n.h>
+#include <__assert>
+#include <__bit/countl.h>
+#include <__charconv/tables.h>
+#include <__charconv/to_chars_base_10.h>
+#include <__charconv/to_chars_result.h>
+#include <__charconv/traits.h>
+#include <__config>
+#include <__cstddef/ptrdiff_t.h>
+#include <__system_error/errc.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/is_integral.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/is_signed.h>
+#include <__type_traits/make_32_64_or_128_bit.h>
+#include <__type_traits/make_unsigned.h>
+#include <__utility/unreachable.h>
+#include <cstdint>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#  pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <typename _Tp>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI __to_chars_result
+__to_chars_itoa(char* __first, char* __last, _Tp __value, false_type);
+
+template <typename _Tp>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI __to_chars_result
+__to_chars_itoa(char* __first, char* __last, _Tp __value, true_type) {
+  auto __x = std::__to_unsigned_like(__value);
+  if (__value < 0 && __first != __last) {
+    *__first++ = '-';
+    __x        = std::__complement(__x);
+  }
+
+  return std::__to_chars_itoa(__first, __last, __x, false_type());
+}
+
+template <typename _Tp>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI __to_chars_result
+__to_chars_itoa(char* __first, char* __last, _Tp __value, false_type) {
+  using __tx  = __itoa::__traits<_Tp>;
+  auto __diff = __last - __first;
+
+  if (__tx::digits <= __diff || __tx::__width(__value) <= __diff)
+    return {__tx::__convert(__first, __value), errc(0)};
+  else
+    return {__last, errc::value_too_large};
+}
+
+#  if _LIBCPP_HAS_INT128
+template <>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI __to_chars_result
+__to_chars_itoa(char* __first, char* __last, __uint128_t __value, false_type) {
+  // When the value fits in 64-bits use the 64-bit code path. This reduces
+  // the number of expensive calculations on 128-bit values.
+  //
+  // NOTE the 128-bit code path requires this optimization.
+  if (__value <= numeric_limits<uint64_t>::max())
+    return __to_chars_itoa(__first, __last, static_cast<uint64_t>(__value), false_type());
+
+  using __tx  = __itoa::__traits<__uint128_t>;
+  auto __diff = __last - __first;
+
+  if (__tx::digits <= __diff || __tx::__width(__value) <= __diff)
+    return {__tx::__convert(__first, __value), errc(0)};
+  else
+    return {__last, errc::value_too_large};
+}
+#  endif
+
+template <class _Tp, __enable_if_t<!is_signed<_Tp>::value, int> = 0>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI __to_chars_result
+__to_chars_integral(char* __first, char* __last, _Tp __value, int __base);
+
+template <class _Tp, __enable_if_t<is_signed<_Tp>::value, int> = 0>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI __to_chars_result
+__to_chars_integral(char* __first, char* __last, _Tp __value, int __base) {
+  auto __x = std::__to_unsigned_like(__value);
+  if (__value < 0 && __first != __last) {
+    *__first++ = '-';
+    __x        = std::__complement(__x);
+  }
+
+  return std::__to_chars_integral(__first, __last, __x, __base);
+}
+
+namespace __itoa {
+
+template <unsigned _Base>
+struct _LIBCPP_HIDDEN __integral;
+
+template <>
+struct _LIBCPP_HIDDEN __integral<2> {
+  template <typename _Tp>
+  _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR int __width(_Tp __value) _NOEXCEPT {
+    // If value == 0 still need one digit. If the value != this has no
+    // effect since the code scans for the most significant bit set.
+    return numeric_limits<_Tp>::digits - std::__countl_zero(__value | 1);
+  }
+
+  template <typename _Tp>
+  _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI static __to_chars_result
+  __to_chars(char* __first, char* __last, _Tp __value) {
+    ptrdiff_t __cap = __last - __first;
+    int __n         = __width(__value);
+    if (__n > __cap)
+      return {__last, errc::value_too_large};
+
+    __last                   = __first + __n;
+    char* __p                = __last;
+    const unsigned __divisor = 16;
+    while (__value > __divisor) {
+      unsigned __c = __value % __divisor;
+      __value /= __divisor;
+      __p -= 4;
+      std::copy_n(&__base_2_lut[4 * __c], 4, __p);
+    }
+    do {
+      unsigned __c = __value % 2;
+      __value /= 2;
+      *--__p = "01"[__c];
+    } while (__value != 0);
+    return {__last, errc(0)};
+  }
+};
+
+template <>
+struct _LIBCPP_HIDDEN __integral<8> {
+  template <typename _Tp>
+  _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR int __width(_Tp __value) _NOEXCEPT {
+    // If value == 0 still need one digit. If the value != this has no
+    // effect since the code scans for the most significat bit set.
+    return ((numeric_limits<_Tp>::digits - std::__countl_zero(__value | 1)) + 2) / 3;
+  }
+
+  template <typename _Tp>
+  _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI static __to_chars_result
+  __to_chars(char* __first, char* __last, _Tp __value) {
+    ptrdiff_t __cap = __last - __first;
+    int __n         = __width(__value);
+    if (__n > __cap)
+      return {__last, errc::value_too_large};
+
+    __last             = __first + __n;
+    char* __p          = __last;
+    unsigned __divisor = 64;
+    while (__value > __divisor) {
+      unsigned __c = __value % __divisor;
+      __value /= __divisor;
+      __p -= 2;
+      std::copy_n(&__base_8_lut[2 * __c], 2, __p);
+    }
+    do {
+      unsigned __c = __value % 8;
+      __value /= 8;
+      *--__p = "01234567"[__c];
+    } while (__value != 0);
+    return {__last, errc(0)};
+  }
+};
+
+template <>
+struct _LIBCPP_HIDDEN __integral<16> {
+  template <typename _Tp>
+  _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR int __width(_Tp __value) _NOEXCEPT {
+    // If value == 0 still need one digit. If the value != this has no
+    // effect since the code scans for the most significat bit set.
+    return (numeric_limits<_Tp>::digits - std::__countl_zero(__value | 1) + 3) / 4;
+  }
+
+  template <typename _Tp>
+  _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI static __to_chars_result
+  __to_chars(char* __first, char* __last, _Tp __value) {
+    ptrdiff_t __cap = __last - __first;
+    int __n         = __width(__value);
+    if (__n > __cap)
+      return {__last, errc::value_too_large};
+
+    __last             = __first + __n;
+    char* __p          = __last;
+    unsigned __divisor = 256;
+    while (__value > __divisor) {
+      unsigned __c = __value % __divisor;
+      __value /= __divisor;
+      __p -= 2;
+      std::copy_n(&__base_16_lut[2 * __c], 2, __p);
+    }
+    if (__first != __last)
+      do {
+        unsigned __c = __value % 16;
+        __value /= 16;
+        *--__p = "0123456789abcdef"[__c];
+      } while (__value != 0);
+    return {__last, errc(0)};
+  }
+};
+
+} // namespace __itoa
+
+template <unsigned _Base, typename _Tp, __enable_if_t<(sizeof(_Tp) >= sizeof(unsigned)), int> = 0>
+_LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI int __to_chars_integral_width(_Tp __value) {
+  return __itoa::__integral<_Base>::__width(__value);
+}
+
+template <unsigned _Base, typename _Tp, __enable_if_t<(sizeof(_Tp) < sizeof(unsigned)), int> = 0>
+_LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI int __to_chars_integral_width(_Tp __value) {
+  return std::__to_chars_integral_width<_Base>(static_cast<unsigned>(__value));
+}
+
+template <unsigned _Base, typename _Tp, __enable_if_t<(sizeof(_Tp) >= sizeof(unsigned)), int> = 0>
+_LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI __to_chars_result
+__to_chars_integral(char* __first, char* __last, _Tp __value) {
+  return __itoa::__integral<_Base>::__to_chars(__first, __last, __value);
+}
+
+template <unsigned _Base, typename _Tp, __enable_if_t<(sizeof(_Tp) < sizeof(unsigned)), int> = 0>
+_LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI __to_chars_result
+__to_chars_integral(char* __first, char* __last, _Tp __value) {
+  return std::__to_chars_integral<_Base>(__first, __last, static_cast<unsigned>(__value));
+}
+
+template <typename _Tp>
+_LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI int __to_chars_integral_width(_Tp __value, unsigned __base) {
+  _LIBCPP_ASSERT_INTERNAL(__value >= 0, "The function requires a non-negative value.");
+
+  unsigned __base_2 = __base * __base;
+  unsigned __base_3 = __base_2 * __base;
+  unsigned __base_4 = __base_2 * __base_2;
+
+  int __r = 0;
+  while (true) {
+    if (__value < __base)
+      return __r + 1;
+    if (__value < __base_2)
+      return __r + 2;
+    if (__value < __base_3)
+      return __r + 3;
+    if (__value < __base_4)
+      return __r + 4;
+
+    __value /= __base_4;
+    __r += 4;
+  }
+
+  __libcpp_unreachable();
+}
+
+template <class _Tp, __enable_if_t<!is_signed<_Tp>::value, int> >
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI __to_chars_result
+__to_chars_integral(char* __first, char* __last, _Tp __value, int __base) {
+  if (__base == 10) [[likely]]
+    return std::__to_chars_itoa(__first, __last, __value, false_type());
+
+  switch (__base) {
+  case 2:
+    return std::__to_chars_integral<2>(__first, __last, __value);
+  case 8:
+    return std::__to_chars_integral<8>(__first, __last, __value);
+  case 16:
+    return std::__to_chars_integral<16>(__first, __last, __value);
+  }
+
+  ptrdiff_t __cap = __last - __first;
+  int __n         = std::__to_chars_integral_width(__value, __base);
+  if (__n > __cap)
+    return {__last, errc::value_too_large};
+
+  __last    = __first + __n;
+  char* __p = __last;
+  do {
+    unsigned __c = __value % __base;
+    __value /= __base;
+    *--__p = "0123456789abcdefghijklmnopqrstuvwxyz"[__c];
+  } while (__value != 0);
+  return {__last, errc(0)};
+}
+
+_LIBCPP_HIDE_FROM_ABI inline _LIBCPP_CONSTEXPR_SINCE_CXX14 char __hex_to_upper(char __c) {
+  switch (__c) {
+  case 'a':
+    return 'A';
+  case 'b':
+    return 'B';
+  case 'c':
+    return 'C';
+  case 'd':
+    return 'D';
+  case 'e':
+    return 'E';
+  case 'f':
+    return 'F';
+  }
+  return __c;
+}
+
+#if _LIBCPP_STD_VER >= 17
+
+to_chars_result to_chars(char*, char*, bool, int = 10) = delete;
+
+template <typename _Tp, __enable_if_t<is_integral<_Tp>::value, int> = 0>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI to_chars_result
+to_chars(char* __first, char* __last, _Tp __value) {
+  using _Type = __make_32_64_or_128_bit_t<_Tp>;
+  static_assert(!is_same<_Type, void>::value, "unsupported integral type used in to_chars");
+  return std::__to_chars_itoa(__first, __last, static_cast<_Type>(__value), is_signed<_Tp>());
+}
+
+template <typename _Tp, __enable_if_t<is_integral<_Tp>::value, int> = 0>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI to_chars_result
+to_chars(char* __first, char* __last, _Tp __value, int __base) {
+  _LIBCPP_ASSERT_UNCATEGORIZED(2 <= __base && __base <= 36, "base not in [2, 36]");
+
+  using _Type = __make_32_64_or_128_bit_t<_Tp>;
+  return std::__to_chars_integral(__first, __last, static_cast<_Type>(__value), __base);
+}
+
+#endif // _LIBCPP_STD_VER >= 17
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___CHARCONV_TO_CHARS_INTEGRAL_H
diff --git a/third_party/libcxx/include/c++/v1/__charconv/to_chars_result.h b/third_party/libcxx/include/c++/v1/__charconv/to_chars_result.h
new file mode 100644
index 0000000..a3cd4e2
--- /dev/null
+++ b/third_party/libcxx/include/c++/v1/__charconv/to_chars_result.h
@@ -0,0 +1,48 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// 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___CHARCONV_TO_CHARS_RESULT_H
+#define _LIBCPP___CHARCONV_TO_CHARS_RESULT_H
+
+#include <__config>
+#include <__system_error/errc.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#  pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+
+struct to_chars_result {
+  char* ptr;
+  errc ec;
+#  if _LIBCPP_STD_VER >= 20
+  _LIBCPP_HIDE_FROM_ABI friend bool operator==(const to_chars_result&, const to_chars_result&) = default;
+#  endif
+#  if _LIBCPP_STD_VER >= 26
+  _LIBCPP_HIDE_FROM_ABI constexpr explicit operator bool() const noexcept { return ec == errc{}; }
+#  endif
+};
+
+#endif // _LIBCPP_STD_VER >= 17
+
+struct __to_chars_result {
+  char* __ptr;
+  errc __ec;
+
+#if _LIBCPP_STD_VER >= 17
+  _LIBCPP_HIDE_FROM_ABI constexpr operator to_chars_result() { return {__ptr, __ec}; }
+#endif
+};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___CHARCONV_TO_CHARS_RESULT_H
diff --git a/third_party/libcxx/include/c++/v1/__charconv/traits.h b/third_party/libcxx/include/c++/v1/__charconv/traits.h
new file mode 100644
index 0000000..b8c840d
--- /dev/null
+++ b/third_party/libcxx/include/c++/v1/__charconv/traits.h
@@ -0,0 +1,167 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// 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___CHARCONV_TRAITS
+#define _LIBCPP___CHARCONV_TRAITS
+
+#include <__assert>
+#include <__bit/countl.h>
+#include <__charconv/tables.h>
+#include <__charconv/to_chars_base_10.h>
+#include <__config>
+#include <__memory/addressof.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_unsigned.h>
+#include <cstdint>
+#include <limits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#  pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace __itoa {
+
+template <typename _Tp, typename = void>
+struct _LIBCPP_HIDDEN __traits_base;
+
+template <typename _Tp>
+struct _LIBCPP_HIDDEN __traits_base<_Tp, __enable_if_t<sizeof(_Tp) <= sizeof(uint32_t)> > {
+  using type = uint32_t;
+
+  /// The width estimation using a log10 algorithm.
+  ///
+  /// The algorithm is based on
+  /// http://graphics.stanford.edu/~seander/bithacks.html#IntegerLog10
+  /// Instead of using IntegerLogBase2 it uses __countl_zero.
+  static _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI int __width(_Tp __v) {
+    auto __t = (32 - std::__countl_zero(static_cast<type>(__v | 1))) * 1233 >> 12;
+    return __t - (__v < __itoa::__pow10_32[__t]) + 1;
+  }
+
+  static _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI char* __convert(char* __p, _Tp __v) {
+    return __itoa::__base_10_u32(__p, __v);
+  }
+
+  static _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI decltype(__pow10_32)& __pow() {
+    return __itoa::__pow10_32;
+  }
+};
+
+template <typename _Tp>
+struct _LIBCPP_HIDDEN __traits_base<_Tp, __enable_if_t<sizeof(_Tp) == sizeof(uint64_t)> > {
+  using type = uint64_t;
+
+  /// The width estimation using a log10 algorithm.
+  ///
+  /// The algorithm is based on
+  /// http://graphics.stanford.edu/~seander/bithacks.html#IntegerLog10
+  /// Instead of using IntegerLogBase2 it uses __countl_zero.
+  static _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI int __width(_Tp __v) {
+    auto __t = (64 - std::__countl_zero(static_cast<type>(__v | 1))) * 1233 >> 12;
+    return __t - (__v < __itoa::__pow10_64[__t]) + 1;
+  }
+
+  static _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI char* __convert(char* __p, _Tp __v) {
+    return __itoa::__base_10_u64(__p, __v);
+  }
+
+  static _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI decltype(__pow10_64)& __pow() {
+    return __itoa::__pow10_64;
+  }
+};
+
+#  if _LIBCPP_HAS_INT128
+template <typename _Tp>
+struct _LIBCPP_HIDDEN __traits_base<_Tp, __enable_if_t<sizeof(_Tp) == sizeof(__uint128_t)> > {
+  using type = __uint128_t;
+
+  /// The width estimation using a log10 algorithm.
+  ///
+  /// The algorithm is based on
+  /// http://graphics.stanford.edu/~seander/bithacks.html#IntegerLog10
+  /// Instead of using IntegerLogBase2 it uses __countl_zero.
+  static _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI int __width(_Tp __v) {
+    _LIBCPP_ASSERT_INTERNAL(
+        __v > numeric_limits<uint64_t>::max(), "The optimizations for this algorithm fail when this isn't true.");
+    // There's always a bit set in the upper 64-bits.
+    auto __t = (128 - std::__countl_zero(static_cast<uint64_t>(__v >> 64))) * 1233 >> 12;
+    _LIBCPP_ASSERT_INTERNAL(__t >= __itoa::__pow10_128_offset, "Index out of bounds");
+    // __t is adjusted since the lookup table misses the lower entries.
+    return __t - (__v < __itoa::__pow10_128[__t - __itoa::__pow10_128_offset]) + 1;
+  }
+
+  static _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI char* __convert(char* __p, _Tp __v) {
+    return __itoa::__base_10_u128(__p, __v);
+  }
+
+  // TODO FMT This pow function should get an index.
+  // By moving this to its own header it can be reused by the pow function in to_chars_base_10.
+  static _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI decltype(__pow10_128)& __pow() {
+    return __itoa::__pow10_128;
+  }
+};
+#  endif
+
+template <typename _Tp, typename _Up>
+_LIBCPP_HIDE_FROM_ABI bool _LIBCPP_CONSTEXPR_SINCE_CXX23 __mul_overflowed(_Tp __a, _Up __b, _Tp& __r) {
+  static_assert(is_unsigned<_Tp>::value);
+  return __builtin_mul_overflow(__a, static_cast<_Tp>(__b), std::addressof(__r));
+}
+
+template <typename _Tp>
+struct _LIBCPP_HIDDEN __traits : __traits_base<_Tp> {
+  static _LIBCPP_CONSTEXPR const int digits = numeric_limits<_Tp>::digits10 + 1;
+  using __traits_base<_Tp>::__pow;
+  using typename __traits_base<_Tp>::type;
+
+  // precondition: at least one non-zero character available
+  static _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI char const*
+  __read(char const* __p, char const* __ep, type& __a, type& __b) {
+    type __cprod[digits];
+    int __j = digits - 1;
+    int __i = digits;
+    do {
+      if (*__p < '0' || *__p > '9')
+        break;
+      __cprod[--__i] = *__p++ - '0';
+    } while (__p != __ep && __i != 0);
+
+    __a = __inner_product(__cprod + __i + 1, __cprod + __j, __pow() + 1, __cprod[__i]);
+    if (__itoa::__mul_overflowed(__cprod[__j], __pow()[__j - __i], __b))
+      --__p;
+    return __p;
+  }
+
+  template <typename _It1, typename _It2, class _Up>
+  static _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI _Up
+  __inner_product(_It1 __first1, _It1 __last1, _It2 __first2, _Up __init) {
+    for (; __first1 < __last1; ++__first1, ++__first2)
+      __init = __init + *__first1 * *__first2;
+    return __init;
+  }
+};
+
+} // namespace __itoa
+
+template <typename _Tp>
+inline _LIBCPP_CONSTEXPR_SINCE_CXX23 _LIBCPP_HIDE_FROM_ABI _Tp __complement(_Tp __x) {
+  static_assert(is_unsigned<_Tp>::value, "cast to unsigned first");
+  return _Tp(~__x + 1);
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___CHARCONV_TRAITS