[libc++] Remove the legacy debug mode.

[var-const]

Summary

See https://discourse.llvm.org/t/rfc-removing-the-legacy-debug-mode-from-libc/71026

[var-const]

Compilation fixes.

[var-const]

CI fix.

[ldionne]

libcxx/CMakeLists.txt

57

Not attached: We should add a release note.

59

Not attached: I think we need to modify the CI setup to remove the debug mode job (and the associated CMake cache).

libcxx/include/__algorithm/unwrap_iter.h

41

This raises an interesting question -- how do we make sure not to forget to come back and re-evaluate what we should do here in the future? I think we should leave some kind of TODO(debug-mode) behind or something like that.

libcxx/include/__format/buffer.h

256

Same here -- those seem like things we'd want to do with our ownership checking and bounded iterators as well?

libcxx/include/vector

1736

A part of me would be tempted to leave those assertions in place like this, just for documentation:

_LIBCPP_LEGACY_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(std::addressof(__position)) == this, "vector::erase(iterator) called with an iterator not referring to this vector");

This would expand to nothing, but it would document what kind of checking we used to do with the debug mode and would inform what we might want to check in the future, when we get there. WDYT?

libcxx/utils/libcxx/test/features.py

310

You should make a pass for the tests that use libcpp-has-debug-mode -- I see a few where stuff like // XFAIL: libcpp-has-debug-mode can be removed.

[var-const]

Address feedback.

[var-const]

libcxx/CMakeLists.txt

59

Thanks!

libcxx/include/__algorithm/unwrap_iter.h

41

I thought to simply use the delta in this patch, but adding a note SGTM.

libcxx/include/vector

1736

I thought about this, but was leaning towards removing those. We still have the effectively-disabled tests that check these assertions, and we can refer to the delta in this patch as well. But I'm definitely open to restoring these.

libcxx/utils/libcxx/test/features.py

310

Thanks!

[Mordante]

Based on the information on discourse no objection against removal in LLVM-17.
LGTM modulo some nits, leaving final approval to @ldionne.

libcxx/CMakeLists.txt

65

This flag is used in docs/DesignDocs/DebugMode.rst, please update that document.

libcxx/docs/ReleaseNotes.rst

77

[var-const]

Feedback.

[var-const]

libcxx/CMakeLists.txt

65

Thanks! I went ahead and removed the file.

[ldionne]

This LGTM once CI is green and comments are applied. Please ping me one last time and I'll only look at the diff-since-last-change real quick. Thanks for the patch, we've been wanting to do this for a long time!

libcxx/include/__algorithm/comp_ref_type.h

53

Should this be UNCATEGORIZED_ASSERT instead? Assuming you land the patch that does the renaming first, I think it should.

libcxx/include/__tree

379–383

I think this should just be a _LIBCPP_UNCATEGORIZED_ASSERT for now. It would work today.

Once we categorize this, this could become something like _LIBCPP_INTERNAL_ASSERTION or something like that since it's effectively an internal consistency check to ensure that our implementation isn't broken. We have other instances of that, and we had thought about adding another assertion macro to handle those back then.

libcxx/include/vector

1736

Ok, sold.

libcxx/utils/gdb/libcxx/printers.py

994

I don't think this is correct -- this apparently pertains to libstdcxx types (per the comment above).

[var-const]

Feedback

libcxx/utils/gdb/libcxx/printers.py

994

Thanks for spotting this!

[var-const]

libcxx/include/__algorithm/comp_ref_type.h

53

I'm getting a weird CI failure on this line from our custom clang-tidy checks:

comp_ref_type.h:53:9: error: ADL lookup [libcpp-robust-against-adl,-warnings-as-errors]
53 |         _LIBCPP_ASSERT(!__comp_(__l, __r),

I don't see how calling __comp_ would involve ADL given that it's a reference (also other calls to __comp_ in this file are not flagged).

How do I run the clang-tidy tests locally in a Docker container? I tried copying the clang-tidy invocation from the CI, but it looks like my local build is missing /llvm/build/generic-cxx23/libcxx/test/tools/clang_tidy_checks/libcxx-tidy.plugin.

[ldionne]

libcxx/include/__algorithm/comp_ref_type.h

53

Use export ENABLE_CLANG_TIDY=On before you do run-buildbot in the docker image!

This can be seen done in buildkite-pipeline.yml. This will cause -DLIBCXX_ENABLE_CLANG_TIDY=On to be passed to the CMake, and the plugin to be compiled.

[var-const]

Fix the CI.

[var-const]

Fix the CI.

[var-const]

libcxx/include/__algorithm/comp_ref_type.h

53

Thanks! Looks like the file was simply missing the <__assert> include so that clang-tidy must have thought that _LIBCPP_ASSERT_UNCATEGORIZED is an undeclared function, resulting in a false positive.

[ldionne]

Ship it! This is great, it's been a long time in the making. Now let's work to bring back some of the important parts that were in there (with an implementation that satisfies the criteria we have now).

[hans]

libcxx/include/__tree

379–383

This caused a few of Chromium's tests to fail.

Since we set _LIBCPP_ENABLE_ASSERTIONS but not _LIBCPP_ENABLE_DEBUG_MODE, this made std::tree<>::erase O(n) instead of O(log n), causing a few of our tests to time out. (crbug.com/1459922)

It seems this kind of check is too expensive for the regular assert mode. Could this check be disabled for now, or is there some alternative "expensive checks" mode it could be part of?

[ldionne]

libcxx/include/__tree

379–383

Interesting -- yes I think this is clearly a debug mode assertion only, we only happen to be in the middle of categorizing those so the current state of the tree doesn't represent what we want to ship in the next release. @var-const I think we could just comment out this assertion if it's causing problems until we categorize it as a debug mode assertion.

[hans]

libcxx/include/__tree

379–383

Sent https://reviews.llvm.org/D154417 to do this.

[alexfh]

libcxx/include/__tree

379–383

We're also seeing a number of test timeouts in checked builds after this patch. Thanks Hans for coming up with a fix!

libcxx/CMakeLists.txt

 #===============================================================================
 include(CMakeDependentOption)
 include(HandleCompilerRT)
 
 # Basic options ---------------------------------------------------------------
 option(LIBCXX_ENABLE_ASSERTIONS
   "Enable assertions inside the compiled library, and at the same time make it the
    default when compiling user code. Note that assertions can be enabled or disabled
    by users in their own code regardless of this option." OFF)
 option(LIBCXX_ENABLE_SHARED "Build libc++ as a shared library." ON)
 option(LIBCXX_ENABLE_STATIC "Build libc++ as a static library." ON)
 option(LIBCXX_ENABLE_FILESYSTEM
   "Whether to include support for parts of the library that rely on a filesystem being
    available on the platform. This includes things like most parts of <filesystem> and
    others like <fstream>" ON)
 option(LIBCXX_INCLUDE_TESTS "Build the libc++ tests." ${LLVM_INCLUDE_TESTS})
-option(LIBCXX_ENABLE_DEBUG_MODE
-  "Whether to build libc++ with the debug mode enabled.
-   By default, this is turned off. Turning it on results in a different ABI (additional
-   symbols but also potentially different layouts of types), and one should not mix code
-   built against a dylib that has debug mode and code built against a regular dylib." OFF)
 option(LIBCXX_ENABLE_RANDOM_DEVICE
   "Whether to include support for std::random_device in the library. Disabling
    this can be useful when building the library for platforms that don't have
    a source of randomness, such as some embedded platforms. When this is not
    supported, most of <random> will still be available, but std::random_device
    will not." ON)
 option(LIBCXX_ENABLE_LOCALIZATION
   "Whether to include support for localization in the library. Disabling
if (NOT ("${LIBCXX_TYPEINFO_COMPARISON_IMPLEMENTATION}" IN_LIST TYPEINFO_COMPARISON_VALUES))
   message(FATAL_ERROR "Value '${LIBCXX_TYPEINFO_COMPARISON_IMPLEMENTATION}' is not a valid value for
                        LIBCXX_TYPEINFO_COMPARISON_IMPLEMENTATION")
 endif()
 
 set(LIBCXX_ABI_DEFINES "" CACHE STRING "A semicolon separated list of ABI macros to define in the site config header.")
 option(LIBCXX_EXTRA_SITE_DEFINES "Extra defines to add into __config_site")
 option(LIBCXX_USE_COMPILER_RT "Use compiler-rt instead of libgcc" OFF)
 
-option(LIBCXX_ENABLE_BACKWARDS_COMPATIBILITY_DEBUG_MODE_SYMBOLS
-  "Whether to include the old Debug mode symbols in the compiled library. This
-   is provided for backwards compatibility since the compiled library used to
-   always contain those symbols, regardless of whether the library was built
-   with the debug mode enabled. This is OFF by default, please contact the libc++
-   developers if you need to turn this on, as this will be removed in LLVM 16." OFF)
-
 # ABI Library options ---------------------------------------------------------
 if (LIBCXX_TARGETING_MSVC)
   set(LIBCXX_DEFAULT_ABI_LIBRARY "vcruntime")
 elseif (${CMAKE_SYSTEM_NAME} MATCHES "FreeBSD")
   set(LIBCXX_DEFAULT_ABI_LIBRARY "libcxxrt")
 else()
   set(LIBCXX_DEFAULT_ABI_LIBRARY "libcxxabi")
 endif()

 config_define_if(LIBCXX_HAS_MUSL_LIBC _LIBCPP_HAS_MUSL_LIBC)
 config_define_if(LIBCXX_NO_VCRUNTIME _LIBCPP_NO_VCRUNTIME)
 config_define_if_not(LIBCXX_ENABLE_FILESYSTEM _LIBCPP_HAS_NO_FILESYSTEM)
 config_define_if_not(LIBCXX_ENABLE_RANDOM_DEVICE _LIBCPP_HAS_NO_RANDOM_DEVICE)
 config_define_if_not(LIBCXX_ENABLE_LOCALIZATION _LIBCPP_HAS_NO_LOCALIZATION)
 config_define_if_not(LIBCXX_ENABLE_UNICODE _LIBCPP_HAS_NO_UNICODE)
 config_define_if_not(LIBCXX_ENABLE_WIDE_CHARACTERS _LIBCPP_HAS_NO_WIDE_CHARACTERS)
 config_define_if_not(LIBCXX_ENABLE_VENDOR_AVAILABILITY_ANNOTATIONS _LIBCPP_HAS_NO_VENDOR_AVAILABILITY_ANNOTATIONS)
-config_define_if(LIBCXX_ENABLE_DEBUG_MODE _LIBCPP_ENABLE_DEBUG_MODE)
 if (LIBCXX_ENABLE_ASSERTIONS)
   config_define(1 _LIBCPP_ENABLE_ASSERTIONS_DEFAULT)
 else()
   config_define(0 _LIBCPP_ENABLE_ASSERTIONS_DEFAULT)
 endif()
 
 if (LIBCXX_PSTL_CPU_BACKEND STREQUAL "serial")
   config_define(1 _LIBCPP_PSTL_CPU_BACKEND_SERIAL)

libcxx/cmake/caches/Generic-debug-mode.cmake

-set(LIBCXX_ENABLE_DEBUG_MODE ON CACHE BOOL "")

libcxx/docs/ReleaseNotes.rst

 - The ``<format>`` header is no longer considered experimental. Some
   ``std::formatter`` specializations are not yet available since the class used
   in the specialization has not been implemented in libc++. This prevents the
   feature-test macro to be set.
 
 Deprecations and Removals
 -------------------------
 
+- The legacy debug mode has been removed in this release. Defining the macro
+  `_LIBCPP_ENABLE_DEBUG_MODE` is now a no-op. The legacy debug mode will be
+  replaced by finer-grained hardened modes. For additional context, refer to
+  the `Discourse post
+  <https://discourse.llvm.org/t/rfc-removing-the-legacy-debug-mode-from-libc/71026>`_
+
 - The ``<experimental/coroutine>`` header has been removed in this release. The ``<coroutine>`` header
   has been shipping since LLVM 14, so the Coroutines TS implementation is being removed per our policy
   for removing TSes.
 
 - Several incidental transitive includes have been removed from libc++. Those
   includes are removed based on the language version used. Incidental transitive
   inclusions of the following headers have been removed:
 

libcxx/include/CMakeLists.txt

set(files
   __concepts/swappable.h
   __concepts/totally_ordered.h
   __condition_variable/condition_variable.h
   __config
   __coroutine/coroutine_handle.h
   __coroutine/coroutine_traits.h
   __coroutine/noop_coroutine_handle.h
   __coroutine/trivial_awaitables.h
-  __debug
   __debug_utils/randomize_range.h
   __debug_utils/strict_weak_ordering_check.h
   __exception/exception.h
   __exception/exception_ptr.h
   __exception/nested_exception.h
   __exception/operations.h
   __exception/terminate.h
   __expected/bad_expected_access.h

libcxx/include/__algorithm/comp_ref_type.h

 //===----------------------------------------------------------------------===//
 //
 // 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___ALGORITHM_COMP_REF_TYPE_H
 #define _LIBCPP___ALGORITHM_COMP_REF_TYPE_H
 
 #include <__config>
-#include <__debug>
 #include <__utility/declval.h>
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #  pragma GCC system_header
 #endif
 
 _LIBCPP_BEGIN_NAMESPACE_STD
 
struct __debug_less
     }
 
     template <class _LHS, class _RHS>
     _LIBCPP_CONSTEXPR_SINCE_CXX14
     inline _LIBCPP_INLINE_VISIBILITY
     decltype((void)std::declval<_Compare&>()(
         std::declval<_LHS &>(), std::declval<_RHS &>()))
     __do_compare_assert(int, _LHS & __l, _RHS & __r) {
-        _LIBCPP_DEBUG_ASSERT(!__comp_(__l, __r),
+        _LIBCPP_ASSERT(!__comp_(__l, __r),
             "Comparator does not induce a strict weak ordering");
         (void)__l;
         (void)__r;
     }
 
     template <class _LHS, class _RHS>
     _LIBCPP_CONSTEXPR_SINCE_CXX14
     inline _LIBCPP_INLINE_VISIBILITY
     void __do_compare_assert(long, _LHS &, _RHS &) {}
 };
 
 // Pass the comparator by lvalue reference. Or in debug mode, using a
 // debugging wrapper that stores a reference.
+// TODO(varconst): update to be used in the new debug mode (or delete entirely).
 #ifdef _LIBCPP_ENABLE_DEBUG_MODE
 template <class _Comp>
 using __comp_ref_type = __debug_less<_Comp>;
 #else
 template <class _Comp>
 using __comp_ref_type = _Comp&;
 #endif
 
 _LIBCPP_END_NAMESPACE_STD
 
 #endif // _LIBCPP___ALGORITHM_COMP_REF_TYPE_H

libcxx/include/__algorithm/nth_element.h

 //===----------------------------------------------------------------------===//
 //
 // 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___ALGORITHM_NTH_ELEMENT_H
 #define _LIBCPP___ALGORITHM_NTH_ELEMENT_H
 
 #include <__algorithm/comp.h>
 #include <__algorithm/comp_ref_type.h>
 #include <__algorithm/iterator_operations.h>
 #include <__algorithm/sort.h>
 #include <__config>
-#include <__debug>
 #include <__debug_utils/randomize_range.h>
 #include <__iterator/iterator_traits.h>
 #include <__utility/move.h>
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #  pragma GCC system_header
 #endif
 

libcxx/include/__algorithm/partial_sort.h

 
 #include <__algorithm/comp.h>
 #include <__algorithm/comp_ref_type.h>
 #include <__algorithm/iterator_operations.h>
 #include <__algorithm/make_heap.h>
 #include <__algorithm/sift_down.h>
 #include <__algorithm/sort_heap.h>
 #include <__config>
-#include <__debug>
 #include <__debug_utils/randomize_range.h>
 #include <__iterator/iterator_traits.h>
 #include <__type_traits/is_copy_assignable.h>
 #include <__type_traits/is_copy_constructible.h>
 #include <__utility/move.h>
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #  pragma GCC system_header

libcxx/include/__algorithm/shuffle.h

 //===----------------------------------------------------------------------===//
 //
 // 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___ALGORITHM_SHUFFLE_H
 #define _LIBCPP___ALGORITHM_SHUFFLE_H
 
 #include <__algorithm/iterator_operations.h>
 #include <__config>
-#include <__debug>
 #include <__iterator/iterator_traits.h>
 #include <__random/uniform_int_distribution.h>
 #include <__utility/forward.h>
 #include <__utility/move.h>
 #include <__utility/swap.h>
 #include <cstddef>
 #include <cstdint>
 

libcxx/include/__algorithm/sort.h

 #include <__algorithm/min_element.h>
 #include <__algorithm/partial_sort.h>
 #include <__algorithm/unwrap_iter.h>
 #include <__assert>
 #include <__bit/blsr.h>
 #include <__bit/countl.h>
 #include <__bit/countr.h>
 #include <__config>
-#include <__debug>
 #include <__debug_utils/randomize_range.h>
 #include <__debug_utils/strict_weak_ordering_check.h>
 #include <__functional/operations.h>
 #include <__functional/ranges_operations.h>
 #include <__iterator/iterator_traits.h>
 #include <__type_traits/conditional.h>
 #include <__type_traits/disjunction.h>
 #include <__type_traits/is_arithmetic.h>
+#include <__type_traits/is_constant_evaluated.h>
 #include <__utility/move.h>
 #include <__utility/pair.h>
 #include <climits>
 #include <cstdint>
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #  pragma GCC system_header
 #endif

libcxx/include/__algorithm/three_way_comp_ref_type.h

 //===----------------------------------------------------------------------===//
 //
 // 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___ALGORITHM_THREE_WAY_COMP_REF_TYPE_H
 #define _LIBCPP___ALGORITHM_THREE_WAY_COMP_REF_TYPE_H
 
 #include <__compare/ordering.h>
 #include <__config>
-#include <__debug>
 #include <__utility/declval.h>
 #include <__utility/forward.h>
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #  pragma GCC system_header
 #endif
 
 _LIBCPP_BEGIN_NAMESPACE_STD
struct __debug_three_way_comp {
 
   template <class _LHS, class _RHS, class _Order>
   _LIBCPP_HIDE_FROM_ABI constexpr void __do_compare_assert(_LHS& __l, _RHS& __r, _Order __o) {
     _Order __expected = __o;
     if (__o == _Order::less)
       __expected = _Order::greater;
     if (__o == _Order::greater)
       __expected = _Order::less;
-    _LIBCPP_DEBUG_ASSERT(__comp_(__l, __r) == __expected, "Comparator does not induce a strict weak ordering");
+    _LIBCPP_ASSERT(__comp_(__l, __r) == __expected, "Comparator does not induce a strict weak ordering");
     (void)__l;
     (void)__r;
   }
 };
 
 // Pass the comparator by lvalue reference. Or in debug mode, using a
 // debugging wrapper that stores a reference.
+// TODO(varconst): update to be used in the new debug mode (or delete entirely).
 #  ifdef _LIBCPP_ENABLE_DEBUG_MODE
 template <class _Comp>
 using __three_way_comp_ref_type = __debug_three_way_comp<_Comp>;
 #  else
 template <class _Comp>
 using __three_way_comp_ref_type = _Comp&;
 #  endif
 
 #endif // _LIBCPP_STD_VER >= 20
 
 _LIBCPP_END_NAMESPACE_STD
 
 #endif // _LIBCPP___ALGORITHM_THREE_WAY_COMP_REF_TYPE_H

libcxx/include/__algorithm/unwrap_iter.h

 #  pragma GCC system_header
 #endif
 
 _LIBCPP_BEGIN_NAMESPACE_STD
 
 // TODO: Change the name of __unwrap_iter_impl to something more appropriate
 // The job of __unwrap_iter is to remove iterator wrappers (like reverse_iterator or __wrap_iter),
 // to reduce the number of template instantiations and to enable pointer-based optimizations e.g. in std::copy.
-// In debug mode, we don't do this.
 //
 // Some algorithms (e.g. std::copy, but not std::sort) need to convert an
 // "unwrapped" result back into the original iterator type. Doing that is the job of __rewrap_iter.
 
 // Default case - we can't unwrap anything
 template <class _Iter, bool = __libcpp_is_contiguous_iterator<_Iter>::value>
 struct __unwrap_iter_impl {
   static _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _Iter __rewrap(_Iter, _Iter __iter) { return __iter; }
   static _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _Iter __unwrap(_Iter __i) _NOEXCEPT { return __i; }
 };
 
-#ifndef _LIBCPP_ENABLE_DEBUG_MODE
+// TODO(hardening): make sure that the following unwrapping doesn't unexpectedly turn hardened iterators into raw
+// pointers.
 
 // It's a contiguous iterator, so we can use a raw pointer instead
 template <class _Iter>
 struct __unwrap_iter_impl<_Iter, true> {
   using _ToAddressT = decltype(std::__to_address(std::declval<_Iter>()));
 
   static _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _Iter __rewrap(_Iter __orig_iter, _ToAddressT __unwrapped_iter) {
     return __orig_iter + (__unwrapped_iter - std::__to_address(__orig_iter));
   }
 
   static _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _ToAddressT __unwrap(_Iter __i) _NOEXCEPT {
     return std::__to_address(__i);
   }
 };
 
-#endif // !_LIBCPP_ENABLE_DEBUG_MODE
-
 template<class _Iter,
          class _Impl = __unwrap_iter_impl<_Iter>,
          __enable_if_t<is_copy_constructible<_Iter>::value, int> = 0>
 inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14
 decltype(_Impl::__unwrap(std::declval<_Iter>())) __unwrap_iter(_Iter __i) _NOEXCEPT {
   return _Impl::__unwrap(__i);
 }
 

libcxx/include/__assert

 
 #include <__config>
 #include <__verbose_abort>
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #  pragma GCC system_header
 #endif
 
-// Automatically enable assertions when the debug mode is enabled.
-#if defined(_LIBCPP_ENABLE_DEBUG_MODE)
-#  ifndef _LIBCPP_ENABLE_ASSERTIONS
-#    define _LIBCPP_ENABLE_ASSERTIONS 1
-#  endif
-#endif
-
 #ifndef _LIBCPP_ENABLE_ASSERTIONS
 #  define _LIBCPP_ENABLE_ASSERTIONS _LIBCPP_ENABLE_ASSERTIONS_DEFAULT
 #endif
 
 #if _LIBCPP_ENABLE_ASSERTIONS != 0 && _LIBCPP_ENABLE_ASSERTIONS != 1
 #  error "_LIBCPP_ENABLE_ASSERTIONS must be set to 0 or 1"
 #endif
 

libcxx/include/__config_site.in

 #cmakedefine _LIBCPP_HAS_NO_VENDOR_AVAILABILITY_ANNOTATIONS
 #cmakedefine _LIBCPP_NO_VCRUNTIME
 #cmakedefine _LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION @_LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION@
 #cmakedefine _LIBCPP_HAS_NO_FILESYSTEM
 #cmakedefine _LIBCPP_HAS_NO_RANDOM_DEVICE
 #cmakedefine _LIBCPP_HAS_NO_LOCALIZATION
 #cmakedefine _LIBCPP_HAS_NO_WIDE_CHARACTERS
 #cmakedefine01 _LIBCPP_ENABLE_ASSERTIONS_DEFAULT
-#cmakedefine _LIBCPP_ENABLE_DEBUG_MODE
 
 // PSTL backends
 #cmakedefine _LIBCPP_PSTL_CPU_BACKEND_SERIAL
 #cmakedefine _LIBCPP_PSTL_CPU_BACKEND_THREAD
 
 // __USE_MINGW_ANSI_STDIO gets redefined on MinGW
 #ifdef __clang__
 #  pragma clang diagnostic push

libcxx/include/__debug

-// -*- 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___DEBUG
-#define _LIBCPP___DEBUG
-
-#include <__assert>
-#include <__config>
-#include <__type_traits/is_constant_evaluated.h>
-#include <cstddef>
-
-#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
-#  pragma GCC system_header
-#endif
-
-#if defined(_LIBCPP_ENABLE_DEBUG_MODE) && !defined(_LIBCPP_CXX03_LANG) && !defined(_LIBCPP_DEBUG_RANDOMIZE_UNSPECIFIED_STABILITY)
-# define _LIBCPP_DEBUG_RANDOMIZE_UNSPECIFIED_STABILITY
-#endif
-
-#if defined(_LIBCPP_ENABLE_DEBUG_MODE) && !defined(_LIBCPP_DEBUG_STRICT_WEAK_ORDERING_CHECK)
-# define _LIBCPP_DEBUG_STRICT_WEAK_ORDERING_CHECK
-#endif
-
-#if defined(_LIBCPP_ENABLE_DEBUG_MODE) && !defined(_LIBCPP_DEBUG_ITERATOR_BOUNDS_CHECKING)
-# define _LIBCPP_DEBUG_ITERATOR_BOUNDS_CHECKING
-#endif
-
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-#   define _LIBCPP_DEBUG_ASSERT(x, m) _LIBCPP_ASSERT(::std::__libcpp_is_constant_evaluated() || (x), m)
-#else
-#   define _LIBCPP_DEBUG_ASSERT(x, m) ((void)0)
-#endif
-
-#if defined(_LIBCPP_ENABLE_DEBUG_MODE) || defined(_LIBCPP_BUILDING_LIBRARY)
-
-_LIBCPP_BEGIN_NAMESPACE_STD
-
-struct _LIBCPP_EXPORTED_FROM_ABI __c_node;
-
-struct _LIBCPP_EXPORTED_FROM_ABI __i_node
-{
-    void* __i_;
-    __i_node* __next_;
-    __c_node* __c_;
-
-    __i_node(const __i_node&) = delete;
-    __i_node& operator=(const __i_node&) = delete;
-
-    _LIBCPP_INLINE_VISIBILITY
-    __i_node(void* __i, __i_node* __next, __c_node* __c)
-        : __i_(__i), __next_(__next), __c_(__c) {}
-    ~__i_node();
-};
-
-struct _LIBCPP_EXPORTED_FROM_ABI __c_node
-{
-    void* __c_;
-    __c_node* __next_;
-    __i_node** beg_;
-    __i_node** end_;
-    __i_node** cap_;
-
-    __c_node(const __c_node&) = delete;
-    __c_node& operator=(const __c_node&) = delete;
-
-    _LIBCPP_INLINE_VISIBILITY
-    explicit __c_node(void* __c, __c_node* __next)
-        : __c_(__c), __next_(__next), beg_(nullptr), end_(nullptr), cap_(nullptr) {}
-    virtual ~__c_node();
-
-    virtual bool __dereferenceable(const void*) const = 0;
-    virtual bool __decrementable(const void*) const = 0;
-    virtual bool __addable(const void*, ptrdiff_t) const = 0;
-    virtual bool __subscriptable(const void*, ptrdiff_t) const = 0;
-
-    void __add(__i_node* __i);
-    _LIBCPP_HIDDEN void __remove(__i_node* __i);
-};
-
-template <class _Cont>
-struct _C_node
-    : public __c_node
-{
-    _LIBCPP_HIDE_FROM_ABI explicit _C_node(void* __c, __c_node* __n)
-        : __c_node(__c, __n) {}
-
-    _LIBCPP_HIDE_FROM_ABI_VIRTUAL bool __dereferenceable(const void*) const override;
-    _LIBCPP_HIDE_FROM_ABI_VIRTUAL bool __decrementable(const void*) const override;
-    _LIBCPP_HIDE_FROM_ABI_VIRTUAL bool __addable(const void*, ptrdiff_t) const override;
-    _LIBCPP_HIDE_FROM_ABI_VIRTUAL bool __subscriptable(const void*, ptrdiff_t) const override;
-};
-
-template <class _Cont>
-inline bool
-_C_node<_Cont>::__dereferenceable(const void* __i) const
-{
-    typedef typename _Cont::const_iterator iterator;
-    const iterator* __j = static_cast<const iterator*>(__i);
-    _Cont* __cp = static_cast<_Cont*>(__c_);
-    return __cp->__dereferenceable(__j);
-}
-
-template <class _Cont>
-inline bool
-_C_node<_Cont>::__decrementable(const void* __i) const
-{
-    typedef typename _Cont::const_iterator iterator;
-    const iterator* __j = static_cast<const iterator*>(__i);
-    _Cont* __cp = static_cast<_Cont*>(__c_);
-    return __cp->__decrementable(__j);
-}
-
-template <class _Cont>
-inline bool
-_C_node<_Cont>::__addable(const void* __i, ptrdiff_t __n) const
-{
-    typedef typename _Cont::const_iterator iterator;
-    const iterator* __j = static_cast<const iterator*>(__i);
-    _Cont* __cp = static_cast<_Cont*>(__c_);
-    return __cp->__addable(__j, __n);
-}
-
-template <class _Cont>
-inline bool
-_C_node<_Cont>::__subscriptable(const void* __i, ptrdiff_t __n) const
-{
-    typedef typename _Cont::const_iterator iterator;
-    const iterator* __j = static_cast<const iterator*>(__i);
-    _Cont* __cp = static_cast<_Cont*>(__c_);
-    return __cp->__subscriptable(__j, __n);
-}
-
-class _LIBCPP_EXPORTED_FROM_ABI __libcpp_db
-{
-    __c_node** __cbeg_;
-    __c_node** __cend_;
-    size_t   __csz_;
-    __i_node** __ibeg_;
-    __i_node** __iend_;
-    size_t   __isz_;
-
-    explicit __libcpp_db();
-public:
-    __libcpp_db(const __libcpp_db&) = delete;
-    __libcpp_db& operator=(const __libcpp_db&) = delete;
-
-    ~__libcpp_db();
-
-    class __db_c_iterator;
-    class __db_c_const_iterator;
-    class __db_i_iterator;
-    class __db_i_const_iterator;
-
-    __db_c_const_iterator __c_end() const;
-    __db_i_const_iterator __i_end() const;
-
-    typedef __c_node*(_InsertConstruct)(void*, void*, __c_node*);
-
-    template <class _Cont>
-    _LIBCPP_INLINE_VISIBILITY static __c_node* __create_C_node(void *__mem, void *__c, __c_node *__next) {
-        return ::new (__mem) _C_node<_Cont>(__c, __next);
-    }
-
-    template <class _Cont>
-    _LIBCPP_INLINE_VISIBILITY
-    void __insert_c(_Cont* __c)
-    {
-        __insert_c(static_cast<void*>(__c), &__create_C_node<_Cont>);
-    }
-
-    void __insert_i(void* __i);
-    void __insert_c(void* __c, _InsertConstruct* __fn);
-    void __erase_c(void* __c);
-
-    void __insert_ic(void* __i, const void* __c);
-    void __iterator_copy(void* __i, const void* __i0);
-    void __erase_i(void* __i);
-
-    void* __find_c_from_i(void* __i) const;
-    void __invalidate_all(void* __c);
-    __c_node* __find_c_and_lock(void* __c) const;
-    __c_node* __find_c(void* __c) const;
-    void unlock() const;
-
-    void swap(void* __c1, void* __c2);
-
-
-    bool __dereferenceable(const void* __i) const;
-    bool __decrementable(const void* __i) const;
-    bool __addable(const void* __i, ptrdiff_t __n) const;
-    bool __subscriptable(const void* __i, ptrdiff_t __n) const;
-    bool __less_than_comparable(const void* __i, const void* __j) const;
-private:
-    _LIBCPP_HIDDEN
-    __i_node* __insert_iterator(void* __i);
-    _LIBCPP_HIDDEN
-    __i_node* __find_iterator(const void* __i) const;
-
-    friend _LIBCPP_EXPORTED_FROM_ABI __libcpp_db* __get_db();
-};
-
-_LIBCPP_EXPORTED_FROM_ABI __libcpp_db* __get_db();
-_LIBCPP_EXPORTED_FROM_ABI const __libcpp_db* __get_const_db();
-
-_LIBCPP_END_NAMESPACE_STD
-
-#endif // defined(_LIBCPP_ENABLE_DEBUG_MODE) || defined(_LIBCPP_BUILDING_LIBRARY)
-
-_LIBCPP_BEGIN_NAMESPACE_STD
-
-template <class _Tp>
-_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 inline void __debug_db_insert_c(_Tp* __c) {
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-    if (!__libcpp_is_constant_evaluated())
-        __get_db()->__insert_c(__c);
-#else
-    (void)(__c);
-#endif
-}
-
-template <class _Tp>
-_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 inline void __debug_db_insert_i(_Tp* __i) {
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-    if (!__libcpp_is_constant_evaluated())
-        __get_db()->__insert_i(__i);
-#else
-    (void)(__i);
-#endif
-}
-
-template <class _Tp>
-_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 inline void __debug_db_erase_c(_Tp* __c) {
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-    if (!__libcpp_is_constant_evaluated())
-        __get_db()->__erase_c(__c);
-#else
-    (void)(__c);
-#endif
-}
-
-template <class _Tp>
-_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 inline void __debug_db_swap(_Tp* __lhs, _Tp* __rhs) {
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-    if (!__libcpp_is_constant_evaluated())
-        __get_db()->swap(__lhs, __rhs);
-#else
-    (void)(__lhs);
-    (void)(__rhs);
-#endif
-}
-
-template <class _Tp>
-_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 inline void __debug_db_invalidate_all(_Tp* __c) {
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-    if (!__libcpp_is_constant_evaluated())
-        __get_db()->__invalidate_all(__c);
-#else
-    (void)(__c);
-#endif
-}
-
-_LIBCPP_END_NAMESPACE_STD
-
-#endif // _LIBCPP___DEBUG

libcxx/include/__format/buffer.h

 /// Since the output is directly written to the underlying storage this class
 /// is just an empty class.
 template <__fmt_char_type _CharT>
 class _LIBCPP_TEMPLATE_VIS __direct_storage {};
 
 template <class _OutIt, class _CharT>
 concept __enable_direct_output = __fmt_char_type<_CharT> &&
     (same_as<_OutIt, _CharT*>
-#ifndef _LIBCPP_ENABLE_DEBUG_MODE
+     // TODO(hardening): the following check might not apply to hardened iterators and might need to be wrapped in an
+     // `#ifdef`.
      || same_as<_OutIt, __wrap_iter<_CharT*>>
-#endif
     );
 
 /// Write policy for directly writing to the underlying output.
 template <class _OutIt, __fmt_char_type _CharT>
 class _LIBCPP_TEMPLATE_VIS __writer_direct {
 public:
   _LIBCPP_HIDE_FROM_ABI explicit __writer_direct(_OutIt __out_it)
       : __out_it_(__out_it) {}

libcxx/include/__format/format_functions.h

 #ifndef _LIBCPP___FORMAT_FORMAT_FUNCTIONS
 #define _LIBCPP___FORMAT_FORMAT_FUNCTIONS
 
 #include <__algorithm/clamp.h>
 #include <__availability>
 #include <__concepts/convertible_to.h>
 #include <__concepts/same_as.h>
 #include <__config>
-#include <__debug>
 #include <__format/buffer.h>
 #include <__format/format_arg.h>
 #include <__format/format_arg_store.h>
 #include <__format/format_args.h>
 #include <__format/format_context.h>
 #include <__format/format_error.h>
 #include <__format/format_parse_context.h>
 #include <__format/format_string.h>

libcxx/include/__format/formatter_bool.h

 // -*- 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___FORMAT_FORMATTER_BOOL_H
 #define _LIBCPP___FORMAT_FORMATTER_BOOL_H
 
 #include <__algorithm/copy.h>
 #include <__availability>
 #include <__config>
-#include <__debug>
 #include <__format/concepts.h>
 #include <__format/format_error.h>
 #include <__format/format_parse_context.h>
 #include <__format/formatter.h>
 #include <__format/formatter_integral.h>
 #include <__format/parser_std_format_spec.h>
 #include <__utility/unreachable.h>
 #include <string_view>

libcxx/include/__format/parser_std_format_spec.h

 
 #include <__algorithm/copy_n.h>
 #include <__algorithm/find_if.h>
 #include <__algorithm/min.h>
 #include <__assert>
 #include <__concepts/arithmetic.h>
 #include <__concepts/same_as.h>
 #include <__config>
-#include <__debug>
 #include <__format/format_arg.h>
 #include <__format/format_error.h>
 #include <__format/format_parse_context.h>
 #include <__format/format_string.h>
 #include <__format/unicode.h>
 #include <__format/width_estimation_table.h>
 #include <__iterator/concepts.h>
 #include <__iterator/readable_traits.h> // iter_value_t

libcxx/include/__hash_table

 #ifndef _LIBCPP___HASH_TABLE
 #define _LIBCPP___HASH_TABLE
 
 #include <__algorithm/max.h>
 #include <__algorithm/min.h>
 #include <__assert>
 #include <__bit/countl.h>
 #include <__config>
-#include <__debug>
 #include <__functional/hash.h>
 #include <__functional/invoke.h>
 #include <__iterator/iterator_traits.h>
 #include <__memory/addressof.h>
 #include <__memory/allocator_traits.h>
 #include <__memory/compressed_pair.h>
 #include <__memory/pointer_traits.h>
 #include <__memory/swap_allocator.h>

 public:
     typedef forward_iterator_tag                           iterator_category;
     typedef typename _NodeTypes::__node_value_type         value_type;
     typedef typename _NodeTypes::difference_type           difference_type;
     typedef value_type&                                    reference;
     typedef typename _NodeTypes::__node_value_type_pointer pointer;
 
     _LIBCPP_INLINE_VISIBILITY __hash_iterator() _NOEXCEPT : __node_(nullptr) {
-        _VSTD::__debug_db_insert_i(this);
     }
 
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-    _LIBCPP_INLINE_VISIBILITY
-    __hash_iterator(const __hash_iterator& __i)
-        : __node_(__i.__node_)
-    {
-        __get_db()->__iterator_copy(this, _VSTD::addressof(__i));
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    ~__hash_iterator()
-    {
-        __get_db()->__erase_i(this);
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    __hash_iterator& operator=(const __hash_iterator& __i)
-    {
-        if (this != _VSTD::addressof(__i))
-        {
-            __get_db()->__iterator_copy(this, _VSTD::addressof(__i));
-            __node_ = __i.__node_;
-        }
-        return *this;
-    }
-#endif // _LIBCPP_ENABLE_DEBUG_MODE
-
     _LIBCPP_INLINE_VISIBILITY
     reference operator*() const {
-        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__dereferenceable(this),
-                             "Attempted to dereference a non-dereferenceable unordered container iterator");
         return __node_->__upcast()->__value_;
     }
 
     _LIBCPP_INLINE_VISIBILITY
     pointer operator->() const {
-        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__dereferenceable(this),
-                           "Attempted to dereference a non-dereferenceable unordered container iterator");
         return pointer_traits<pointer>::pointer_to(__node_->__upcast()->__value_);
     }
 
     _LIBCPP_INLINE_VISIBILITY
     __hash_iterator& operator++() {
-        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__dereferenceable(this),
-                       "Attempted to increment a non-incrementable unordered container iterator");
         __node_ = __node_->__next_;
         return *this;
     }
 
     _LIBCPP_INLINE_VISIBILITY
     __hash_iterator operator++(int)
     {
         __hash_iterator __t(*this);
         ++(*this);
         return __t;
     }
 
     friend _LIBCPP_INLINE_VISIBILITY
     bool operator==(const __hash_iterator& __x, const __hash_iterator& __y)
     {
         return __x.__node_ == __y.__node_;
     }
     friend _LIBCPP_INLINE_VISIBILITY
     bool operator!=(const __hash_iterator& __x, const __hash_iterator& __y)
         {return !(__x == __y);}
 
 private:
     _LIBCPP_INLINE_VISIBILITY
-    explicit __hash_iterator(__next_pointer __node, const void* __c) _NOEXCEPT
+    explicit __hash_iterator(__next_pointer __node) _NOEXCEPT
         : __node_(__node)
         {
-            (void)__c;
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-            __get_db()->__insert_ic(this, __c);
-#endif
         }
+
     template <class, class, class, class> friend class __hash_table;
     template <class> friend class _LIBCPP_TEMPLATE_VIS __hash_const_iterator;
     template <class> friend class _LIBCPP_TEMPLATE_VIS __hash_map_iterator;
     template <class, class, class, class, class> friend class _LIBCPP_TEMPLATE_VIS unordered_map;
     template <class, class, class, class, class> friend class _LIBCPP_TEMPLATE_VIS unordered_multimap;
 };
 
 template <class _NodePtr>
public:
     typedef forward_iterator_tag                                 iterator_category;
     typedef typename _NodeTypes::__node_value_type               value_type;
     typedef typename _NodeTypes::difference_type                 difference_type;
     typedef const value_type&                                    reference;
     typedef typename _NodeTypes::__const_node_value_type_pointer pointer;
 
 
     _LIBCPP_INLINE_VISIBILITY __hash_const_iterator() _NOEXCEPT : __node_(nullptr) {
-        _VSTD::__debug_db_insert_i(this);
     }
 
     _LIBCPP_INLINE_VISIBILITY
     __hash_const_iterator(const __non_const_iterator& __x) _NOEXCEPT
         : __node_(__x.__node_)
     {
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-        __get_db()->__iterator_copy(this, _VSTD::addressof(__x));
-#endif
     }
 
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-    _LIBCPP_INLINE_VISIBILITY
-    __hash_const_iterator(const __hash_const_iterator& __i)
-        : __node_(__i.__node_)
-    {
-        __get_db()->__iterator_copy(this, _VSTD::addressof(__i));
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    ~__hash_const_iterator()
-    {
-        __get_db()->__erase_i(this);
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    __hash_const_iterator& operator=(const __hash_const_iterator& __i)
-    {
-        if (this != _VSTD::addressof(__i))
-        {
-            __get_db()->__iterator_copy(this, _VSTD::addressof(__i));
-            __node_ = __i.__node_;
-        }
-        return *this;
-    }
-#endif // _LIBCPP_ENABLE_DEBUG_MODE
-
     _LIBCPP_INLINE_VISIBILITY
     reference operator*() const {
-        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__dereferenceable(this),
-                           "Attempted to dereference a non-dereferenceable unordered container const_iterator");
         return __node_->__upcast()->__value_;
     }
     _LIBCPP_INLINE_VISIBILITY
     pointer operator->() const {
-        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__dereferenceable(this),
-                           "Attempted to dereference a non-dereferenceable unordered container const_iterator");
         return pointer_traits<pointer>::pointer_to(__node_->__upcast()->__value_);
     }
 
     _LIBCPP_INLINE_VISIBILITY
     __hash_const_iterator& operator++() {
-        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__dereferenceable(this),
-                             "Attempted to increment a non-incrementable unordered container const_iterator");
         __node_ = __node_->__next_;
         return *this;
     }
 
     _LIBCPP_INLINE_VISIBILITY
     __hash_const_iterator operator++(int)
     {
         __hash_const_iterator __t(*this);
         ++(*this);
         return __t;
     }
 
     friend _LIBCPP_INLINE_VISIBILITY
     bool operator==(const __hash_const_iterator& __x, const __hash_const_iterator& __y)
     {
         return __x.__node_ == __y.__node_;
     }
     friend _LIBCPP_INLINE_VISIBILITY
     bool operator!=(const __hash_const_iterator& __x, const __hash_const_iterator& __y)
         {return !(__x == __y);}
 
 private:
     _LIBCPP_INLINE_VISIBILITY
-    explicit __hash_const_iterator(__next_pointer __node, const void* __c) _NOEXCEPT
+    explicit __hash_const_iterator(__next_pointer __node) _NOEXCEPT
         : __node_(__node)
         {
-            (void)__c;
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-            __get_db()->__insert_ic(this, __c);
-#endif
         }
+
     template <class, class, class, class> friend class __hash_table;
     template <class> friend class _LIBCPP_TEMPLATE_VIS __hash_map_const_iterator;
     template <class, class, class, class, class> friend class _LIBCPP_TEMPLATE_VIS unordered_map;
     template <class, class, class, class, class> friend class _LIBCPP_TEMPLATE_VIS unordered_multimap;
 };
 
 template <class _NodePtr>
 class _LIBCPP_TEMPLATE_VIS __hash_local_iterator

 public:
     typedef forward_iterator_tag                                iterator_category;
     typedef typename _NodeTypes::__node_value_type              value_type;
     typedef typename _NodeTypes::difference_type                difference_type;
     typedef value_type&                                         reference;
     typedef typename _NodeTypes::__node_value_type_pointer      pointer;
 
     _LIBCPP_INLINE_VISIBILITY __hash_local_iterator() _NOEXCEPT : __node_(nullptr) {
-        _VSTD::__debug_db_insert_i(this);
-    }
-
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-    _LIBCPP_INLINE_VISIBILITY
-    __hash_local_iterator(const __hash_local_iterator& __i)
-        : __node_(__i.__node_),
-          __bucket_(__i.__bucket_),
-          __bucket_count_(__i.__bucket_count_)
-    {
-        __get_db()->__iterator_copy(this, _VSTD::addressof(__i));
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    ~__hash_local_iterator()
-    {
-        __get_db()->__erase_i(this);
     }
 
     _LIBCPP_INLINE_VISIBILITY
-    __hash_local_iterator& operator=(const __hash_local_iterator& __i)
-    {
-        if (this != _VSTD::addressof(__i))
-        {
-            __get_db()->__iterator_copy(this, _VSTD::addressof(__i));
-            __node_ = __i.__node_;
-            __bucket_ = __i.__bucket_;
-            __bucket_count_ = __i.__bucket_count_;
-        }
-        return *this;
-    }
-#endif // _LIBCPP_ENABLE_DEBUG_MODE
-
-    _LIBCPP_INLINE_VISIBILITY
     reference operator*() const {
-        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__dereferenceable(this),
-                           "Attempted to dereference a non-dereferenceable unordered container local_iterator");
         return __node_->__upcast()->__value_;
     }
 
     _LIBCPP_INLINE_VISIBILITY
     pointer operator->() const {
-        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__dereferenceable(this),
-                             "Attempted to dereference a non-dereferenceable unordered container local_iterator");
         return pointer_traits<pointer>::pointer_to(__node_->__upcast()->__value_);
     }
 
     _LIBCPP_INLINE_VISIBILITY
     __hash_local_iterator& operator++() {
-        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__dereferenceable(this),
-                       "Attempted to increment a non-incrementable unordered container local_iterator");
         __node_ = __node_->__next_;
         if (__node_ != nullptr && std::__constrain_hash(__node_->__hash(), __bucket_count_) != __bucket_)
             __node_ = nullptr;
         return *this;
     }
 
     _LIBCPP_INLINE_VISIBILITY
     __hash_local_iterator operator++(int)
public:
     }
     friend _LIBCPP_INLINE_VISIBILITY
     bool operator!=(const __hash_local_iterator& __x, const __hash_local_iterator& __y)
         {return !(__x == __y);}
 
 private:
     _LIBCPP_INLINE_VISIBILITY
     explicit __hash_local_iterator(__next_pointer __node, size_t __bucket,
-                                   size_t __bucket_count, const void* __c) _NOEXCEPT
+                                   size_t __bucket_count) _NOEXCEPT
         : __node_(__node),
           __bucket_(__bucket),
           __bucket_count_(__bucket_count)
         {
-            (void)__c;
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-            __get_db()->__insert_ic(this, __c);
-#endif
             if (__node_ != nullptr)
                 __node_ = __node_->__next_;
         }
+
     template <class, class, class, class> friend class __hash_table;
     template <class> friend class _LIBCPP_TEMPLATE_VIS __hash_const_local_iterator;
     template <class> friend class _LIBCPP_TEMPLATE_VIS __hash_map_iterator;
 };
 
 template <class _ConstNodePtr>
 class _LIBCPP_TEMPLATE_VIS __hash_const_local_iterator
 {
public:
     typedef forward_iterator_tag                                 iterator_category;
     typedef typename _NodeTypes::__node_value_type               value_type;
     typedef typename _NodeTypes::difference_type                 difference_type;
     typedef const value_type&                                    reference;
     typedef typename _NodeTypes::__const_node_value_type_pointer pointer;
 
 
     _LIBCPP_INLINE_VISIBILITY __hash_const_local_iterator() _NOEXCEPT : __node_(nullptr) {
-        _VSTD::__debug_db_insert_i(this);
     }
 
     _LIBCPP_INLINE_VISIBILITY
     __hash_const_local_iterator(const __non_const_iterator& __x) _NOEXCEPT
         : __node_(__x.__node_),
           __bucket_(__x.__bucket_),
           __bucket_count_(__x.__bucket_count_)
     {
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-        __get_db()->__iterator_copy(this, _VSTD::addressof(__x));
-#endif
     }
 
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-    _LIBCPP_INLINE_VISIBILITY
-    __hash_const_local_iterator(const __hash_const_local_iterator& __i)
-        : __node_(__i.__node_),
-          __bucket_(__i.__bucket_),
-          __bucket_count_(__i.__bucket_count_)
-    {
-        __get_db()->__iterator_copy(this, _VSTD::addressof(__i));
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    ~__hash_const_local_iterator()
-    {
-        __get_db()->__erase_i(this);
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    __hash_const_local_iterator& operator=(const __hash_const_local_iterator& __i)
-    {
-        if (this != _VSTD::addressof(__i))
-        {
-            __get_db()->__iterator_copy(this, _VSTD::addressof(__i));
-            __node_ = __i.__node_;
-            __bucket_ = __i.__bucket_;
-            __bucket_count_ = __i.__bucket_count_;
-        }
-        return *this;
-    }
-#endif // _LIBCPP_ENABLE_DEBUG_MODE
-
     _LIBCPP_INLINE_VISIBILITY
     reference operator*() const {
-        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__dereferenceable(this),
-                           "Attempted to dereference a non-dereferenceable unordered container const_local_iterator");
         return __node_->__upcast()->__value_;
     }
 
     _LIBCPP_INLINE_VISIBILITY
     pointer operator->() const {
-        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__dereferenceable(this),
-                           "Attempted to dereference a non-dereferenceable unordered container const_local_iterator");
         return pointer_traits<pointer>::pointer_to(__node_->__upcast()->__value_);
     }
 
     _LIBCPP_INLINE_VISIBILITY
     __hash_const_local_iterator& operator++() {
-        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__dereferenceable(this),
-                       "Attempted to increment a non-incrementable unordered container const_local_iterator");
         __node_ = __node_->__next_;
         if (__node_ != nullptr && std::__constrain_hash(__node_->__hash(), __bucket_count_) != __bucket_)
             __node_ = nullptr;
         return *this;
     }
 
     _LIBCPP_INLINE_VISIBILITY
     __hash_const_local_iterator operator++(int)
public:
     }
     friend _LIBCPP_INLINE_VISIBILITY
     bool operator!=(const __hash_const_local_iterator& __x, const __hash_const_local_iterator& __y)
         {return !(__x == __y);}
 
 private:
     _LIBCPP_INLINE_VISIBILITY
     explicit __hash_const_local_iterator(__next_pointer __node_ptr, size_t __bucket,
-                                         size_t __bucket_count, const void* __c) _NOEXCEPT
+                                         size_t __bucket_count) _NOEXCEPT
         : __node_(__node_ptr),
           __bucket_(__bucket),
           __bucket_count_(__bucket_count)
         {
-            (void)__c;
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-            __get_db()->__insert_ic(this, __c);
-#endif
             if (__node_ != nullptr)
                 __node_ = __node_->__next_;
         }
+
     template <class, class, class, class> friend class __hash_table;
     template <class> friend class _LIBCPP_TEMPLATE_VIS __hash_map_const_iterator;
 };
 
 template <class _Alloc>
 class __bucket_list_deallocator
 {
     typedef _Alloc                                          allocator_type;
#endif
     }
 
     _LIBCPP_INLINE_VISIBILITY
     local_iterator
     begin(size_type __n)
     {
         _LIBCPP_ASSERT(__n < bucket_count(),
             "unordered container::begin(n) called with n >= bucket_count()");
-        return local_iterator(__bucket_list_[__n], __n, bucket_count(), this);
+        return local_iterator(__bucket_list_[__n], __n, bucket_count());
     }
 
     _LIBCPP_INLINE_VISIBILITY
     local_iterator
     end(size_type __n)
     {
         _LIBCPP_ASSERT(__n < bucket_count(),
             "unordered container::end(n) called with n >= bucket_count()");
-        return local_iterator(nullptr, __n, bucket_count(), this);
+        return local_iterator(nullptr, __n, bucket_count());
     }
 
     _LIBCPP_INLINE_VISIBILITY
     const_local_iterator
     cbegin(size_type __n) const
     {
         _LIBCPP_ASSERT(__n < bucket_count(),
             "unordered container::cbegin(n) called with n >= bucket_count()");
-        return const_local_iterator(__bucket_list_[__n], __n, bucket_count(), this);
+        return const_local_iterator(__bucket_list_[__n], __n, bucket_count());
     }
 
     _LIBCPP_INLINE_VISIBILITY
     const_local_iterator
     cend(size_type __n) const
     {
         _LIBCPP_ASSERT(__n < bucket_count(),
             "unordered container::cend(n) called with n >= bucket_count()");
-        return const_local_iterator(nullptr, __n, bucket_count(), this);
+        return const_local_iterator(nullptr, __n, bucket_count());
     }
 
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-
-    _LIBCPP_HIDE_FROM_ABI bool __dereferenceable(const const_iterator* __i) const;
-    _LIBCPP_HIDE_FROM_ABI bool __decrementable(const const_iterator* __i) const;
-    _LIBCPP_HIDE_FROM_ABI bool __addable(const const_iterator* __i, ptrdiff_t __n) const;
-    _LIBCPP_HIDE_FROM_ABI bool __subscriptable(const const_iterator* __i, ptrdiff_t __n) const;
-
-#endif // _LIBCPP_ENABLE_DEBUG_MODE
-
 private:
     template <bool _UniqueKeys>
     _LIBCPP_HIDE_FROM_ABI void __rehash(size_type __n);
     template <bool _UniqueKeys>
     _LIBCPP_HIDE_FROM_ABI void __do_rehash(size_type __n);
 
     template <class ..._Args>
     _LIBCPP_HIDE_FROM_ABI __node_holder __construct_node(_Args&& ...__args);

 #if defined(_LIBCPP_CXX03_LANG)
     static_assert((is_copy_constructible<key_equal>::value),
                  "Predicate must be copy-constructible.");
     static_assert((is_copy_constructible<hasher>::value),
                  "Hasher must be copy-constructible.");
 #endif
 
     __deallocate_node(__p1_.first().__next_);
-    std::__debug_db_erase_c(this);
 }
 
 template <class _Tp, class _Hash, class _Equal, class _Alloc>
 void
 __hash_table<_Tp, _Hash, _Equal, _Alloc>::__copy_assign_alloc(
         const __hash_table& __u, true_type)
 {
     if (__node_alloc() != __u.__node_alloc())

 void
 __hash_table<_Tp, _Hash, _Equal, _Alloc>::__deallocate_node(__next_pointer __np)
     _NOEXCEPT
 {
     __node_allocator& __na = __node_alloc();
     while (__np != nullptr)
     {
         __next_pointer __next = __np->__next_;
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-        __c_node* __c = __get_db()->__find_c_and_lock(this);
-        for (__i_node** __p = __c->end_; __p != __c->beg_; )
-        {
-            --__p;
-            iterator* __i = static_cast<iterator*>((*__p)->__i_);
-            if (__i->__node_ == __np)
-            {
-                (*__p)->__c_ = nullptr;
-                if (--__c->end_ != __p)
-                    _VSTD::memmove(__p, __p+1, (__c->end_ - __p)*sizeof(__i_node*));
-            }
-        }
-        __get_db()->unlock();
-#endif
         __node_pointer __real_np = __np->__upcast();
         __node_traits::destroy(__na, _NodeTypes::__get_ptr(__real_np->__value_));
         __node_traits::deallocate(__na, __real_np, 1);
         __np = __next;
     }
 }
 
 template <class _Tp, class _Hash, class _Equal, class _Alloc>
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__move_assign(
     __p1_.first().__next_ = __u.__p1_.first().__next_;
     if (size() > 0)
     {
         __bucket_list_[std::__constrain_hash(__p1_.first().__next_->__hash(), bucket_count())] =
             __p1_.first().__ptr();
         __u.__p1_.first().__next_ = nullptr;
         __u.size() = 0;
     }
-    std::__debug_db_swap(this, std::addressof(__u));
 }
 
 template <class _Tp, class _Hash, class _Equal, class _Alloc>
 void
 __hash_table<_Tp, _Hash, _Equal, _Alloc>::__move_assign(
         __hash_table& __u, false_type)
 {
     if (__node_alloc() == __u.__node_alloc())
for (; __first != __last; ++__first)
         __insert_multi(_NodeTypes::__get_value(*__first));
 }
 
 template <class _Tp, class _Hash, class _Equal, class _Alloc>
 inline
 typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
 __hash_table<_Tp, _Hash, _Equal, _Alloc>::begin() _NOEXCEPT
 {
-    return iterator(__p1_.first().__next_, this);
+    return iterator(__p1_.first().__next_);
 }
 
 template <class _Tp, class _Hash, class _Equal, class _Alloc>
 inline
 typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
 __hash_table<_Tp, _Hash, _Equal, _Alloc>::end() _NOEXCEPT
 {
-    return iterator(nullptr, this);
+    return iterator(nullptr);
 }
 
 template <class _Tp, class _Hash, class _Equal, class _Alloc>
 inline
 typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::const_iterator
 __hash_table<_Tp, _Hash, _Equal, _Alloc>::begin() const _NOEXCEPT
 {
-    return const_iterator(__p1_.first().__next_, this);
+    return const_iterator(__p1_.first().__next_);
 }
 
 template <class _Tp, class _Hash, class _Equal, class _Alloc>
 inline
 typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::const_iterator
 __hash_table<_Tp, _Hash, _Equal, _Alloc>::end() const _NOEXCEPT
 {
-    return const_iterator(nullptr, this);
+    return const_iterator(nullptr);
 }
 
 template <class _Tp, class _Hash, class _Equal, class _Alloc>
 void
 __hash_table<_Tp, _Hash, _Equal, _Alloc>::clear() _NOEXCEPT
 {
     if (size() > 0)
     {
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_insert_unique(__node_pointer __nd)
     // Insert the node, unless it already exists in the container.
     bool __inserted = false;
     if (__existing_node == nullptr)
     {
         __node_insert_unique_perform(__nd);
         __existing_node = __nd->__ptr();
         __inserted = true;
     }
-    return pair<iterator, bool>(iterator(__existing_node, this), __inserted);
+    return pair<iterator, bool>(iterator(__existing_node), __inserted);
 }
 
 // Prepare the container for an insertion of the value __cp_val with the hash
 // __cp_hash. This does a lookup into the container to see if __cp_value is
 // already present, and performs a rehash if necessary. Returns a pointer to the
 // last occurrence of __cp_val in the map.
 //
 // Note that this function does forward exceptions if key_eq() throws, and never

 template <class _Tp, class _Hash, class _Equal, class _Alloc>
 typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
 __hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_insert_multi(__node_pointer __cp)
 {
     __cp->__hash_ = hash_function()(__cp->__value_);
     __next_pointer __pn = __node_insert_multi_prepare(__cp->__hash(), __cp->__value_);
     __node_insert_multi_perform(__cp, __pn);
 
-    return iterator(__cp->__ptr(), this);
+    return iterator(__cp->__ptr());
 }
 
 template <class _Tp, class _Hash, class _Equal, class _Alloc>
 typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
 __hash_table<_Tp, _Hash, _Equal, _Alloc>::__node_insert_multi(
         const_iterator __p, __node_pointer __cp)
 {
-    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(_VSTD::addressof(__p)) == this,
-                         "unordered container::emplace_hint(const_iterator, args...) called with an iterator not"
-                         " referring to this unordered container");
     if (__p != end() && key_eq()(*__p, __cp->__value_))
     {
         __next_pointer __np = __p.__node_;
         __cp->__hash_ = __np->__hash();
         size_type __bc = bucket_count();
         if (size()+1 > __bc * max_load_factor() || __bc == 0)
         {
             __rehash_multi(_VSTD::max<size_type>(2 * __bc + !std::__is_hash_power2(__bc),
                            size_type(std::ceil(float(size() + 1) / max_load_factor()))));
             __bc = bucket_count();
         }
         size_t __chash = std::__constrain_hash(__cp->__hash_, __bc);
         __next_pointer __pp = __bucket_list_[__chash];
         while (__pp->__next_ != __np)
             __pp = __pp->__next_;
         __cp->__next_ = __np;
         __pp->__next_ = static_cast<__next_pointer>(__cp);
         ++size();
-        return iterator(static_cast<__next_pointer>(__cp), this);
+        return iterator(static_cast<__next_pointer>(__cp));
     }
     return __node_insert_multi(__cp);
 }
 
 
 
 template <class _Tp, class _Hash, class _Equal, class _Alloc>
 template <class _Key, class ..._Args>
if (__bc != 0)
             __pn->__next_ = static_cast<__next_pointer>(__h.get());
         }
         __nd = static_cast<__next_pointer>(__h.release());
         // increment size
         ++size();
         __inserted = true;
     }
 __done:
-    return pair<iterator, bool>(iterator(__nd, this), __inserted);
+    return pair<iterator, bool>(iterator(__nd), __inserted);
 }
 
 template <class _Tp, class _Hash, class _Equal, class _Alloc>
 template <class... _Args>
 pair<typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator, bool>
 __hash_table<_Tp, _Hash, _Equal, _Alloc>::__emplace_unique_impl(_Args&&... __args)
 {
     __node_holder __h = __construct_node(_VSTD::forward<_Args>(__args)...);

 }
 
 template <class _Tp, class _Hash, class _Equal, class _Alloc>
 template <class... _Args>
 typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
 __hash_table<_Tp, _Hash, _Equal, _Alloc>::__emplace_hint_multi(
         const_iterator __p, _Args&&... __args)
 {
-    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(_VSTD::addressof(__p)) == this,
-                         "unordered container::emplace_hint(const_iterator, args...) called with an iterator not"
-                         " referring to this unordered container");
     __node_holder __h = __construct_node(_VSTD::forward<_Args>(__args)...);
     iterator __r = __node_insert_multi(__p, __h.get());
     __h.release();
     return __r;
 }
 
 #if _LIBCPP_STD_VER >= 17
 template <class _Tp, class _Hash, class _Equal, class _Alloc>
_LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK
     }
 }
 
 template <class _Tp, class _Hash, class _Equal, class _Alloc>
 template <bool _UniqueKeys>
 void
 __hash_table<_Tp, _Hash, _Equal, _Alloc>::__do_rehash(size_type __nbc)
 {
-    std::__debug_db_invalidate_all(this);
     __pointer_allocator& __npa = __bucket_list_.get_deleter().__alloc();
     __bucket_list_.reset(__nbc > 0 ?
                       __pointer_alloc_traits::allocate(__npa, __nbc) : nullptr);
     __bucket_list_.get_deleter().size() = __nbc;
     if (__nbc > 0)
     {
         for (size_type __i = 0; __i < __nbc; ++__i)
             __bucket_list_[__i] = nullptr;
if (__bc != 0)
         {
             for (__nd = __nd->__next_; __nd != nullptr &&
                 (__nd->__hash() == __hash
                   || std::__constrain_hash(__nd->__hash(), __bc) == __chash);
                                                            __nd = __nd->__next_)
             {
                 if ((__nd->__hash() == __hash)
                     && key_eq()(__nd->__upcast()->__value_, __k))
-                    return iterator(__nd, this);
+                    return iterator(__nd);
             }
         }
     }
     return end();
 }
 
 template <class _Tp, class _Hash, class _Equal, class _Alloc>
 template <class _Key>
if (__bc != 0)
         {
             for (__nd = __nd->__next_; __nd != nullptr &&
                 (__hash == __nd->__hash()
                     || std::__constrain_hash(__nd->__hash(), __bc) == __chash);
                                                            __nd = __nd->__next_)
             {
                 if ((__nd->__hash() == __hash)
                     && key_eq()(__nd->__upcast()->__value_, __k))
-                    return const_iterator(__nd, this);
+                    return const_iterator(__nd);
             }
         }
 
     }
     return end();
 }
 
 template <class _Tp, class _Hash, class _Equal, class _Alloc>
__hash_table<_Tp, _Hash, _Equal, _Alloc>::__construct_node_hash(
     return __h;
 }
 
 template <class _Tp, class _Hash, class _Equal, class _Alloc>
 typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
 __hash_table<_Tp, _Hash, _Equal, _Alloc>::erase(const_iterator __p)
 {
     __next_pointer __np = __p.__node_;
-    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(_VSTD::addressof(__p)) == this,
-                         "unordered container erase(iterator) called with an iterator not"
-                         " referring to this container");
     _LIBCPP_ASSERT(__p != end(),
                    "unordered container erase(iterator) called with a non-dereferenceable iterator");
-    iterator __r(__np, this);
+    iterator __r(__np);
     ++__r;
     remove(__p);
     return __r;
 }
 
 template <class _Tp, class _Hash, class _Equal, class _Alloc>
 typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::iterator
 __hash_table<_Tp, _Hash, _Equal, _Alloc>::erase(const_iterator __first,
                                                 const_iterator __last)
 {
-    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(_VSTD::addressof(__first)) == this,
-                         "unordered container::erase(iterator, iterator) called with an iterator not"
-                         " referring to this container");
-    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(_VSTD::addressof(__last)) == this,
-                         "unordered container::erase(iterator, iterator) called with an iterator not"
-                         " referring to this container");
     for (const_iterator __p = __first; __first != __last; __p = __first)
     {
         ++__first;
         erase(__p);
     }
     __next_pointer __np = __last.__node_;
-    return iterator (__np, this);
+    return iterator (__np);
 }
 
 template <class _Tp, class _Hash, class _Equal, class _Alloc>
 template <class _Key>
 typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::size_type
 __hash_table<_Tp, _Hash, _Equal, _Alloc>::__erase_unique(const _Key& __k)
 {
     iterator __i = find(__k);
if (__cn->__next_ != nullptr)
         size_t __nhash = std::__constrain_hash(__cn->__next_->__hash(), __bc);
         if (__nhash != __chash)
             __bucket_list_[__nhash] = __pn;
     }
     // remove __cn
     __pn->__next_ = __cn->__next_;
     __cn->__next_ = nullptr;
     --size();
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-    __c_node* __c = __get_db()->__find_c_and_lock(this);
-    for (__i_node** __dp = __c->end_; __dp != __c->beg_; )
-    {
-        --__dp;
-        iterator* __i = static_cast<iterator*>((*__dp)->__i_);
-        if (__i->__node_ == __cn)
-        {
-            (*__dp)->__c_ = nullptr;
-            if (--__c->end_ != __dp)
-                _VSTD::memmove(__dp, __dp+1, (__c->end_ - __dp)*sizeof(__i_node*));
-        }
-    }
-    __get_db()->unlock();
-#endif
     return __node_holder(__cn->__upcast(), _Dp(__node_alloc(), true));
 }
 
 template <class _Tp, class _Hash, class _Equal, class _Alloc>
 template <class _Key>
 inline
 typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::size_type
 __hash_table<_Tp, _Hash, _Equal, _Alloc>::__count_unique(const _Key& __k) const
#endif
     __p2_.swap(__u.__p2_);
     __p3_.swap(__u.__p3_);
     if (size() > 0)
         __bucket_list_[std::__constrain_hash(__p1_.first().__next_->__hash(), bucket_count())] =
             __p1_.first().__ptr();
     if (__u.size() > 0)
         __u.__bucket_list_[std::__constrain_hash(__u.__p1_.first().__next_->__hash(), __u.bucket_count())] =
             __u.__p1_.first().__ptr();
-    std::__debug_db_swap(this, std::addressof(__u));
 }
 
 template <class _Tp, class _Hash, class _Equal, class _Alloc>
 typename __hash_table<_Tp, _Hash, _Equal, _Alloc>::size_type
 __hash_table<_Tp, _Hash, _Equal, _Alloc>::bucket_size(size_type __n) const
 {
     _LIBCPP_ASSERT(__n < bucket_count(),
         "unordered container::bucket_size(n) called with n >= bucket_count()");

 void
 swap(__hash_table<_Tp, _Hash, _Equal, _Alloc>& __x,
      __hash_table<_Tp, _Hash, _Equal, _Alloc>& __y)
     _NOEXCEPT_(_NOEXCEPT_(__x.swap(__y)))
 {
     __x.swap(__y);
 }
 
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-
-template <class _Tp, class _Hash, class _Equal, class _Alloc>
-bool
-__hash_table<_Tp, _Hash, _Equal, _Alloc>::__dereferenceable(const const_iterator* __i) const
-{
-    return __i->__node_ != nullptr;
-}
-
-template <class _Tp, class _Hash, class _Equal, class _Alloc>
-bool
-__hash_table<_Tp, _Hash, _Equal, _Alloc>::__decrementable(const const_iterator*) const
-{
-    return false;
-}
-
-template <class _Tp, class _Hash, class _Equal, class _Alloc>
-bool
-__hash_table<_Tp, _Hash, _Equal, _Alloc>::__addable(const const_iterator*, ptrdiff_t) const
-{
-    return false;
-}
-
-template <class _Tp, class _Hash, class _Equal, class _Alloc>
-bool
-__hash_table<_Tp, _Hash, _Equal, _Alloc>::__subscriptable(const const_iterator*, ptrdiff_t) const
-{
-    return false;
-}
-
-#endif // _LIBCPP_ENABLE_DEBUG_MODE
-
 _LIBCPP_END_NAMESPACE_STD
 
 _LIBCPP_POP_MACROS
 
 #endif // _LIBCPP___HASH_TABLE

libcxx/include/__iterator/wrap_iter.h

 // -*- 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___ITERATOR_WRAP_ITER_H
 #define _LIBCPP___ITERATOR_WRAP_ITER_H
 
 #include <__config>
-#include <__debug>
 #include <__iterator/iterator_traits.h>
 #include <__memory/addressof.h>
 #include <__memory/pointer_traits.h>
 #include <__type_traits/enable_if.h>
 #include <__type_traits/is_convertible.h>
+#include <cstddef>
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #  pragma GCC system_header
 #endif
 
 _LIBCPP_BEGIN_NAMESPACE_STD
 
 template <class _Iter>

 #endif
 
 private:
     iterator_type __i_;
 public:
     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter() _NOEXCEPT
                 : __i_()
     {
-        _VSTD::__debug_db_insert_i(this);
     }
     template <class _Up> _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14
         __wrap_iter(const __wrap_iter<_Up>& __u,
             typename enable_if<is_convertible<_Up, iterator_type>::value>::type* = nullptr) _NOEXCEPT
             : __i_(__u.base())
     {
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-      if (!__libcpp_is_constant_evaluated())
-        __get_db()->__iterator_copy(this, _VSTD::addressof(__u));
-#endif
-    }
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14
-    __wrap_iter(const __wrap_iter& __x)
-        : __i_(__x.base())
-    {
-      if (!__libcpp_is_constant_evaluated())
-        __get_db()->__iterator_copy(this, _VSTD::addressof(__x));
-    }
-    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14
-    __wrap_iter& operator=(const __wrap_iter& __x)
-    {
-        if (this != _VSTD::addressof(__x))
-        {
-            if (!__libcpp_is_constant_evaluated())
-                __get_db()->__iterator_copy(this, _VSTD::addressof(__x));
-            __i_ = __x.__i_;
-        }
-        return *this;
     }
-    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
-    ~__wrap_iter()
-    {
-      if (!__libcpp_is_constant_evaluated())
-        __get_db()->__erase_i(this);
-    }
-#endif
     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 reference operator*() const _NOEXCEPT
     {
-        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__dereferenceable(this),
-                             "Attempted to dereference a non-dereferenceable iterator");
         return *__i_;
     }
     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 pointer operator->() const _NOEXCEPT
     {
-        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__dereferenceable(this),
-                             "Attempted to dereference a non-dereferenceable iterator");
         return _VSTD::__to_address(__i_);
     }
     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter& operator++() _NOEXCEPT
     {
-        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__dereferenceable(this),
-                             "Attempted to increment a non-incrementable iterator");
         ++__i_;
         return *this;
     }
     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter  operator++(int) _NOEXCEPT
         {__wrap_iter __tmp(*this); ++(*this); return __tmp;}
 
     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter& operator--() _NOEXCEPT
     {
-        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__decrementable(this),
-                             "Attempted to decrement a non-decrementable iterator");
         --__i_;
         return *this;
     }
     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter  operator--(int) _NOEXCEPT
         {__wrap_iter __tmp(*this); --(*this); return __tmp;}
     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter  operator+ (difference_type __n) const _NOEXCEPT
         {__wrap_iter __w(*this); __w += __n; return __w;}
     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter& operator+=(difference_type __n) _NOEXCEPT
     {
-        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__addable(this, __n),
-                             "Attempted to add/subtract an iterator outside its valid range");
         __i_ += __n;
         return *this;
     }
     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter  operator- (difference_type __n) const _NOEXCEPT
         {return *this + (-__n);}
     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __wrap_iter& operator-=(difference_type __n) _NOEXCEPT
         {*this += -__n; return *this;}
     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 reference    operator[](difference_type __n) const _NOEXCEPT
     {
-        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__subscriptable(this, __n),
-                             "Attempted to subscript an iterator outside its valid range");
         return __i_[__n];
     }
 
     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 iterator_type base() const _NOEXCEPT {return __i_;}
 
 private:
     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14
-    explicit __wrap_iter(const void* __p, iterator_type __x) _NOEXCEPT : __i_(__x)
+    explicit __wrap_iter(iterator_type __x) _NOEXCEPT : __i_(__x)
     {
-        (void)__p;
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-      if (!__libcpp_is_constant_evaluated())
-        __get_db()->__insert_ic(this, __p);
-#endif
     }
 
     template <class _Up> friend class __wrap_iter;
     template <class _CharT, class _Traits, class _Alloc> friend class basic_string;
     template <class _Tp, class _Alloc> friend class _LIBCPP_TEMPLATE_VIS vector;
     template <class _Tp, size_t> friend class _LIBCPP_TEMPLATE_VIS span;
 };
 

 {
     return __x.base() == __y.base();
 }
 
 template <class _Iter1>
 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14
 bool operator<(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEXCEPT
 {
-    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__less_than_comparable(_VSTD::addressof(__x), _VSTD::addressof(__y)),
-                         "Attempted to compare incomparable iterators");
     return __x.base() < __y.base();
 }
 
 template <class _Iter1, class _Iter2>
 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14
 bool operator<(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT
 {
-    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__less_than_comparable(&__x, &__y),
-                         "Attempted to compare incomparable iterators");
     return __x.base() < __y.base();
 }
 
 template <class _Iter1>
 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR
 bool operator!=(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter1>& __y) _NOEXCEPT
 {
     return !(__x == __y);

 #ifndef _LIBCPP_CXX03_LANG
 auto operator-(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT
     -> decltype(__x.base() - __y.base())
 #else
 typename __wrap_iter<_Iter1>::difference_type
 operator-(const __wrap_iter<_Iter1>& __x, const __wrap_iter<_Iter2>& __y) _NOEXCEPT
 #endif // C++03
 {
-    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__less_than_comparable(_VSTD::addressof(__x), _VSTD::addressof(__y)),
-                         "Attempted to subtract incompatible iterators");
     return __x.base() - __y.base();
 }
 
 template <class _Iter1>
 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14
 __wrap_iter<_Iter1> operator+(typename __wrap_iter<_Iter1>::difference_type __n, __wrap_iter<_Iter1> __x) _NOEXCEPT
 {
     __x += __n;

libcxx/include/__ranges/filter_view.h

 #define _LIBCPP___RANGES_FILTER_VIEW_H
 
 #include <__algorithm/ranges_find_if.h>
 #include <__concepts/constructible.h>
 #include <__concepts/copyable.h>
 #include <__concepts/derived_from.h>
 #include <__concepts/equality_comparable.h>
 #include <__config>
-#include <__debug>
 #include <__functional/bind_back.h>
 #include <__functional/invoke.h>
 #include <__functional/reference_wrapper.h>
 #include <__iterator/concepts.h>
 #include <__iterator/iter_move.h>
 #include <__iterator/iter_swap.h>
 #include <__iterator/iterator_traits.h>
 #include <__memory/addressof.h>

libcxx/include/__tree

 // -*- 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___TREE
 #define _LIBCPP___TREE
 
 #include <__algorithm/min.h>
 #include <__assert>
 #include <__config>
-#include <__debug>
 #include <__functional/invoke.h>
 #include <__iterator/distance.h>
 #include <__iterator/iterator_traits.h>
 #include <__iterator/next.h>
 #include <__memory/addressof.h>
 #include <__memory/allocator_traits.h>
 #include <__memory/compressed_pair.h>
 #include <__memory/pointer_traits.h>

 //                nor any of its children refer to __z.  end_node->__left_
 //                may be different than the value passed in as __root.
 template <class _NodePtr>
 _LIBCPP_HIDE_FROM_ABI void
 __tree_remove(_NodePtr __root, _NodePtr __z) _NOEXCEPT
 {
     _LIBCPP_ASSERT(__root != nullptr, "Root node should not be null");
     _LIBCPP_ASSERT(__z != nullptr, "The node to remove should not be null");
-    _LIBCPP_DEBUG_ASSERT(std::__tree_invariant(__root), "The tree invariants should hold");
+    // TODO(varconst): make this work with the new debug mode (or remove).
+#ifdef _LIBCPP_ENABLE_DEBUG_MODE
+    _LIBCPP_ASSERT(std::__tree_invariant(__root), "The tree invariants should hold");
+#endif
     // __z will be removed from the tree.  Client still needs to destruct/deallocate it
     // __y is either __z, or if __z has two children, __tree_next(__z).
     // __y will have at most one child.
     // __y will be the initial hole in the tree (make the hole at a leaf)
     _NodePtr __y = (__z->__left_ == nullptr || __z->__right_ == nullptr) ?
                     __z : _VSTD::__tree_next(__z);
     // __x is __y's possibly null single child
     _NodePtr __x = __y->__left_ != nullptr ? __y->__left_ : __y->__right_;
     // __w is __x's possibly null uncle (will become __x's sibling)

libcxx/include/algorithm

template <class BidirectionalIterator, class Compare>
     constexpr bool     // constexpr in C++20
     prev_permutation(BidirectionalIterator first, BidirectionalIterator last, Compare comp);
 }  // std
 
 */
 
 #include <__assert> // all public C++ headers provide the assertion handler
 #include <__config>
-#include <__debug>
 #include <cstddef>
 #include <version>
 
 #include <__algorithm/adjacent_find.h>
 #include <__algorithm/all_of.h>
 #include <__algorithm/any_of.h>
 #include <__algorithm/binary_search.h>
 #include <__algorithm/clamp.h>

libcxx/include/charconv

 #include <__charconv/tables.h>
 #include <__charconv/to_chars.h>
 #include <__charconv/to_chars_base_10.h>
 #include <__charconv/to_chars_floating_point.h>
 #include <__charconv/to_chars_integral.h>
 #include <__charconv/to_chars_result.h>
 #include <__charconv/traits.h>
 #include <__config>
-#include <__debug>
 #include <__system_error/errc.h>
 #include <cmath> // for log2f
 #include <cstdint>
 #include <limits>
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #  pragma GCC system_header
 #endif

libcxx/include/functional

POLICY:  For non-variadic implementations, the number of arguments is limited
          will be minimal.
 
 */
 
 #include <__algorithm/search.h>
 #include <__assert> // all public C++ headers provide the assertion handler
 #include <__compare/compare_three_way.h>
 #include <__config>
-#include <__debug>
 #include <__functional/binary_function.h>
 #include <__functional/binary_negate.h>
 #include <__functional/bind.h>
 #include <__functional/bind_back.h>
 #include <__functional/bind_front.h>
 #include <__functional/binder1st.h>
 #include <__functional/binder2nd.h>
 #include <__functional/boyer_moore_searcher.h>

libcxx/include/iterator

 template <class E> constexpr const E* data(initializer_list<E> il) noexcept;      // C++17
 
 }  // std
 
 */
 
 #include <__assert> // all public C++ headers provide the assertion handler
 #include <__config>
-#include <__debug>
 #include <__iterator/access.h>
 #include <__iterator/advance.h>
 #include <__iterator/back_insert_iterator.h>
 #include <__iterator/bounded_iter.h>
 #include <__iterator/common_iterator.h>
 #include <__iterator/concepts.h>
 #include <__iterator/counted_iterator.h>
 #include <__iterator/data.h>

libcxx/include/list

 #include <__algorithm/comp.h>
 #include <__algorithm/equal.h>
 #include <__algorithm/lexicographical_compare.h>
 #include <__algorithm/lexicographical_compare_three_way.h>
 #include <__algorithm/min.h>
 #include <__assert> // all public C++ headers provide the assertion handler
 #include <__availability>
 #include <__config>
-#include <__debug>
 #include <__format/enable_insertable.h>
 #include <__iterator/distance.h>
 #include <__iterator/iterator_traits.h>
 #include <__iterator/move_iterator.h>
 #include <__iterator/next.h>
 #include <__iterator/prev.h>
 #include <__iterator/reverse_iterator.h>
 #include <__memory/addressof.h>

 class _LIBCPP_TEMPLATE_VIS __list_iterator
 {
     typedef __list_node_pointer_traits<_Tp, _VoidPtr> _NodeTraits;
     typedef typename _NodeTraits::__link_pointer __link_pointer;
 
     __link_pointer __ptr_;
 
     _LIBCPP_INLINE_VISIBILITY
-    explicit __list_iterator(__link_pointer __p, const void* __c) _NOEXCEPT
+    explicit __list_iterator(__link_pointer __p) _NOEXCEPT
         : __ptr_(__p)
     {
-        (void)__c;
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-        __get_db()->__insert_ic(this, __c);
-#endif
     }
 
     template<class, class> friend class list;
     template<class, class> friend class __list_imp;
     template<class, class> friend class __list_const_iterator;
 public:
     typedef bidirectional_iterator_tag       iterator_category;
     typedef _Tp                              value_type;
     typedef value_type&                      reference;
     typedef __rebind_pointer_t<_VoidPtr, value_type> pointer;
     typedef typename pointer_traits<pointer>::difference_type difference_type;
 
     _LIBCPP_INLINE_VISIBILITY
     __list_iterator() _NOEXCEPT : __ptr_(nullptr)
     {
-        _VSTD::__debug_db_insert_i(this);
-    }
-
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-
-    _LIBCPP_INLINE_VISIBILITY
-    __list_iterator(const __list_iterator& __p)
-        : __ptr_(__p.__ptr_)
-    {
-        __get_db()->__iterator_copy(this, _VSTD::addressof(__p));
     }
 
     _LIBCPP_INLINE_VISIBILITY
-    ~__list_iterator()
-    {
-        __get_db()->__erase_i(this);
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    __list_iterator& operator=(const __list_iterator& __p)
-    {
-        if (this != _VSTD::addressof(__p))
-        {
-            __get_db()->__iterator_copy(this, _VSTD::addressof(__p));
-            __ptr_ = __p.__ptr_;
-        }
-        return *this;
-    }
-
-#endif // _LIBCPP_ENABLE_DEBUG_MODE
-
-    _LIBCPP_INLINE_VISIBILITY
     reference operator*() const
     {
-        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__dereferenceable(this),
-                             "Attempted to dereference a non-dereferenceable list::iterator");
         return __ptr_->__as_node()->__value_;
     }
     _LIBCPP_INLINE_VISIBILITY
     pointer operator->() const
     {
-        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__dereferenceable(this),
-                             "Attempted to dereference a non-dereferenceable list::iterator");
         return pointer_traits<pointer>::pointer_to(__ptr_->__as_node()->__value_);
     }
 
     _LIBCPP_INLINE_VISIBILITY
     __list_iterator& operator++()
     {
-        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__dereferenceable(this),
-                             "Attempted to increment a non-incrementable list::iterator");
         __ptr_ = __ptr_->__next_;
         return *this;
     }
     _LIBCPP_INLINE_VISIBILITY
     __list_iterator operator++(int) {__list_iterator __t(*this); ++(*this); return __t;}
 
     _LIBCPP_INLINE_VISIBILITY
     __list_iterator& operator--()
     {
-        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__decrementable(this),
-                             "Attempted to decrement a non-decrementable list::iterator");
         __ptr_ = __ptr_->__prev_;
         return *this;
     }
     _LIBCPP_INLINE_VISIBILITY
     __list_iterator operator--(int) {__list_iterator __t(*this); --(*this); return __t;}
 
     friend _LIBCPP_INLINE_VISIBILITY
     bool operator==(const __list_iterator& __x, const __list_iterator& __y)

 class _LIBCPP_TEMPLATE_VIS __list_const_iterator
 {
     typedef __list_node_pointer_traits<_Tp, _VoidPtr> _NodeTraits;
     typedef typename _NodeTraits::__link_pointer __link_pointer;
 
     __link_pointer __ptr_;
 
     _LIBCPP_INLINE_VISIBILITY
-    explicit __list_const_iterator(__link_pointer __p, const void* __c) _NOEXCEPT
+    explicit __list_const_iterator(__link_pointer __p) _NOEXCEPT
         : __ptr_(__p)
     {
-        (void)__c;
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-        __get_db()->__insert_ic(this, __c);
-#endif
     }
 
     template<class, class> friend class list;
     template<class, class> friend class __list_imp;
 public:
     typedef bidirectional_iterator_tag       iterator_category;
     typedef _Tp                              value_type;
     typedef const value_type&                reference;
     typedef __rebind_pointer_t<_VoidPtr, const value_type> pointer;
     typedef typename pointer_traits<pointer>::difference_type difference_type;
 
     _LIBCPP_INLINE_VISIBILITY
     __list_const_iterator() _NOEXCEPT : __ptr_(nullptr)
     {
-        _VSTD::__debug_db_insert_i(this);
     }
     _LIBCPP_INLINE_VISIBILITY
     __list_const_iterator(const __list_iterator<_Tp, _VoidPtr>& __p) _NOEXCEPT
         : __ptr_(__p.__ptr_)
     {
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-        __get_db()->__iterator_copy(this, _VSTD::addressof(__p));
-#endif
-    }
-
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-
-    _LIBCPP_INLINE_VISIBILITY
-    __list_const_iterator(const __list_const_iterator& __p)
-        : __ptr_(__p.__ptr_)
-    {
-        __get_db()->__iterator_copy(this, _VSTD::addressof(__p));
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    ~__list_const_iterator()
-    {
-        __get_db()->__erase_i(this);
     }
 
     _LIBCPP_INLINE_VISIBILITY
-    __list_const_iterator& operator=(const __list_const_iterator& __p)
-    {
-        if (this != _VSTD::addressof(__p))
-        {
-            __get_db()->__iterator_copy(this, _VSTD::addressof(__p));
-            __ptr_ = __p.__ptr_;
-        }
-        return *this;
-    }
-
-#endif // _LIBCPP_ENABLE_DEBUG_MODE
-    _LIBCPP_INLINE_VISIBILITY
     reference operator*() const
     {
-        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__dereferenceable(this),
-                             "Attempted to dereference a non-dereferenceable list::const_iterator");
         return __ptr_->__as_node()->__value_;
     }
     _LIBCPP_INLINE_VISIBILITY
     pointer operator->() const
     {
-        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__dereferenceable(this),
-                             "Attempted to dereference a non-dereferenceable list::const_iterator");
         return pointer_traits<pointer>::pointer_to(__ptr_->__as_node()->__value_);
     }
 
     _LIBCPP_INLINE_VISIBILITY
     __list_const_iterator& operator++()
     {
-        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__dereferenceable(this),
-                             "Attempted to increment a non-incrementable list::const_iterator");
         __ptr_ = __ptr_->__next_;
         return *this;
     }
     _LIBCPP_INLINE_VISIBILITY
     __list_const_iterator operator++(int) {__list_const_iterator __t(*this); ++(*this); return __t;}
 
     _LIBCPP_INLINE_VISIBILITY
     __list_const_iterator& operator--()
     {
-        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__decrementable(this),
-                             "Attempted to decrement a non-decrementable list::const_iterator");
         __ptr_ = __ptr_->__prev_;
         return *this;
     }
     _LIBCPP_INLINE_VISIBILITY
     __list_const_iterator operator--(int) {__list_const_iterator __t(*this); --(*this); return __t;}
 
     friend _LIBCPP_INLINE_VISIBILITY
     bool operator==(const __list_const_iterator& __x, const __list_const_iterator& __y)
#endif
     _LIBCPP_HIDE_FROM_ABI ~__list_imp();
     _LIBCPP_HIDE_FROM_ABI void clear() _NOEXCEPT;
     _LIBCPP_INLINE_VISIBILITY
     bool empty() const _NOEXCEPT {return __sz() == 0;}
 
     _LIBCPP_INLINE_VISIBILITY
     iterator begin() _NOEXCEPT
     {
-        return iterator(__end_.__next_, this);
+        return iterator(__end_.__next_);
     }
     _LIBCPP_INLINE_VISIBILITY
     const_iterator begin() const  _NOEXCEPT
     {
-        return const_iterator(__end_.__next_, this);
+        return const_iterator(__end_.__next_);
     }
     _LIBCPP_INLINE_VISIBILITY
     iterator end() _NOEXCEPT
     {
-        return iterator(__end_as_link(), this);
+        return iterator(__end_as_link());
     }
     _LIBCPP_INLINE_VISIBILITY
     const_iterator end() const _NOEXCEPT
     {
-        return const_iterator(__end_as_link(), this);
+        return const_iterator(__end_as_link());
     }
 
     _LIBCPP_HIDE_FROM_ABI void swap(__list_imp& __c)
 #if _LIBCPP_STD_VER >= 14
         _NOEXCEPT;
 #else
         _NOEXCEPT_(!__alloc_traits::propagate_on_container_swap::value ||
                     __is_nothrow_swappable<allocator_type>::value);

 template <class _Tp, class _Alloc>
 inline __list_imp<_Tp, _Alloc>::__list_imp(__node_allocator&& __a) _NOEXCEPT
     : __size_alloc_(0, _VSTD::move(__a)) {}
 #endif
 
 template <class _Tp, class _Alloc>
 __list_imp<_Tp, _Alloc>::~__list_imp() {
   clear();
-  std::__debug_db_erase_c(this);
 }
 
 template <class _Tp, class _Alloc>
 void
 __list_imp<_Tp, _Alloc>::clear() _NOEXCEPT
 {
     if (!empty())
     {
         __node_allocator& __na = __node_alloc();
         __link_pointer __f = __end_.__next_;
         __link_pointer __l = __end_as_link();
         __unlink_nodes(__f, __l->__prev_);
         __sz() = 0;
         while (__f != __l)
         {
             __node_pointer __np = __f->__as_node();
             __f = __f->__next_;
             __node_alloc_traits::destroy(__na, _VSTD::addressof(__np->__value_));
             __node_alloc_traits::deallocate(__na, __np, 1);
         }
-        std::__debug_db_invalidate_all(this);
     }
 }
 
 template <class _Tp, class _Alloc>
 void
 __list_imp<_Tp, _Alloc>::swap(__list_imp& __c)
 #if _LIBCPP_STD_VER >= 14
         _NOEXCEPT
#endif
     if (__sz() == 0)
         __end_.__next_ = __end_.__prev_ = __end_as_link();
     else
         __end_.__prev_->__next_ = __end_.__next_->__prev_ = __end_as_link();
     if (__c.__sz() == 0)
         __c.__end_.__next_ = __c.__end_.__prev_ = __c.__end_as_link();
     else
         __c.__end_.__prev_->__next_ = __c.__end_.__next_->__prev_ = __c.__end_as_link();
-
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-    __libcpp_db* __db = __get_db();
-    __c_node* __cn1 = __db->__find_c_and_lock(this);
-    __c_node* __cn2 = __db->__find_c(_VSTD::addressof(__c));
-    _VSTD::swap(__cn1->beg_, __cn2->beg_);
-    _VSTD::swap(__cn1->end_, __cn2->end_);
-    _VSTD::swap(__cn1->cap_, __cn2->cap_);
-    for (__i_node** __p = __cn1->end_; __p != __cn1->beg_;)
-    {
-        --__p;
-        const_iterator* __i = static_cast<const_iterator*>((*__p)->__i_);
-        if (__i->__ptr_ == __c.__end_as_link())
-        {
-            __cn2->__add(*__p);
-            if (--__cn1->end_ != __p)
-                _VSTD::memmove(__p, __p+1, (__cn1->end_ - __p)*sizeof(__i_node*));
-        }
-        else
-            (*__p)->__c_ = __cn1;
-    }
-    for (__i_node** __p = __cn2->end_; __p != __cn2->beg_;)
-    {
-        --__p;
-        const_iterator* __i = static_cast<const_iterator*>((*__p)->__i_);
-        if (__i->__ptr_ == __end_as_link())
-        {
-            __cn1->__add(*__p);
-            if (--__cn2->end_ != __p)
-                _VSTD::memmove(__p, __p+1, (__cn2->end_ - __p)*sizeof(__i_node*));
-        }
-        else
-            (*__p)->__c_ = __cn2;
-    }
-    __db->unlock();
-#endif
 }
 
 template <class _Tp, class _Alloc /*= allocator<_Tp>*/>
 class _LIBCPP_TEMPLATE_VIS list
     : private __list_imp<_Tp, _Alloc>
 {
     typedef __list_imp<_Tp, _Alloc> base;
     typedef typename base::__node              __node;
#endif
     static_assert(is_same<allocator_type, __rebind_alloc<allocator_traits<allocator_type>, value_type> >::value,
                   "[allocator.requirements] states that rebinding an allocator to the same type should result in the "
                   "original allocator");
 
     _LIBCPP_INLINE_VISIBILITY
     list()
         _NOEXCEPT_(is_nothrow_default_constructible<__node_allocator>::value)
     {
-        _VSTD::__debug_db_insert_c(this);
     }
     _LIBCPP_INLINE_VISIBILITY
     explicit list(const allocator_type& __a) : base(__a)
     {
-        _VSTD::__debug_db_insert_c(this);
     }
     _LIBCPP_HIDE_FROM_ABI explicit list(size_type __n);
 #if _LIBCPP_STD_VER >= 14
     _LIBCPP_HIDE_FROM_ABI explicit list(size_type __n, const allocator_type& __a);
 #endif
     _LIBCPP_HIDE_FROM_ABI list(size_type __n, const value_type& __x);
     template <class = __enable_if_t<__is_allocator<_Alloc>::value> >
     _LIBCPP_HIDE_FROM_ABI list(size_type __n, const value_type& __x, const allocator_type& __a) : base(__a)
     {
-        _VSTD::__debug_db_insert_c(this);
         for (; __n > 0; --__n)
             push_back(__x);
     }
 
     template <class _InpIter>
     _LIBCPP_HIDE_FROM_ABI list(_InpIter __f, _InpIter __l,
              __enable_if_t<__has_input_iterator_category<_InpIter>::value>* = 0);
     template <class _InpIter>
#endif
 
     _LIBCPP_INLINE_VISIBILITY
     __hold_pointer __allocate_node(__node_allocator& __na) {
       __node_pointer __p = __node_alloc_traits::allocate(__na, 1);
       __p->__prev_ = nullptr;
       return __hold_pointer(__p, __node_destructor(__na, 1));
     }
 
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-
-    bool __dereferenceable(const const_iterator* __i) const;
-    bool __decrementable(const const_iterator* __i) const;
-    bool __addable(const const_iterator* __i, ptrdiff_t __n) const;
-    bool __subscriptable(const const_iterator* __i, ptrdiff_t __n) const;
-
-#endif // _LIBCPP_ENABLE_DEBUG_MODE
-
 private:
     _LIBCPP_INLINE_VISIBILITY
     static void __link_nodes  (__link_pointer __p, __link_pointer __f, __link_pointer __l);
     _LIBCPP_INLINE_VISIBILITY
     void __link_nodes_at_front(__link_pointer __f, __link_pointer __l);
     _LIBCPP_INLINE_VISIBILITY
     void __link_nodes_at_back (__link_pointer __f, __link_pointer __l);
     _LIBCPP_HIDE_FROM_ABI iterator __iterator(size_type __n);

 {
     return __n <= base::__sz() / 2 ? _VSTD::next(begin(), __n)
                                    : _VSTD::prev(end(), base::__sz() - __n);
 }
 
 template <class _Tp, class _Alloc>
 list<_Tp, _Alloc>::list(size_type __n)
 {
-    _VSTD::__debug_db_insert_c(this);
     for (; __n > 0; --__n)
 #ifndef _LIBCPP_CXX03_LANG
         emplace_back();
 #else
         push_back(value_type());
 #endif
 }
 
 #if _LIBCPP_STD_VER >= 14
 template <class _Tp, class _Alloc>
 list<_Tp, _Alloc>::list(size_type __n, const allocator_type& __a) : base(__a)
 {
-    _VSTD::__debug_db_insert_c(this);
     for (; __n > 0; --__n)
         emplace_back();
 }
 #endif
 
 template <class _Tp, class _Alloc>
 list<_Tp, _Alloc>::list(size_type __n, const value_type& __x)
 {
-    _VSTD::__debug_db_insert_c(this);
     for (; __n > 0; --__n)
         push_back(__x);
 }
 
 template <class _Tp, class _Alloc>
 template <class _InpIter>
 list<_Tp, _Alloc>::list(_InpIter __f, _InpIter __l,
                         __enable_if_t<__has_input_iterator_category<_InpIter>::value>*)
 {
-    _VSTD::__debug_db_insert_c(this);
     for (; __f != __l; ++__f)
         __emplace_back(*__f);
 }
 
 template <class _Tp, class _Alloc>
 template <class _InpIter>
 list<_Tp, _Alloc>::list(_InpIter __f, _InpIter __l, const allocator_type& __a,
                         __enable_if_t<__has_input_iterator_category<_InpIter>::value>*)
     : base(__a)
 {
-    _VSTD::__debug_db_insert_c(this);
     for (; __f != __l; ++__f)
         __emplace_back(*__f);
 }
 
 template <class _Tp, class _Alloc>
 list<_Tp, _Alloc>::list(const list& __c)
     : base(__node_alloc_traits::select_on_container_copy_construction(
           __c.__node_alloc())) {
-    _VSTD::__debug_db_insert_c(this);
     for (const_iterator __i = __c.begin(), __e = __c.end(); __i != __e; ++__i)
         push_back(*__i);
 }
 
 template <class _Tp, class _Alloc>
 list<_Tp, _Alloc>::list(const list& __c, const __type_identity_t<allocator_type>& __a)
     : base(__a)
 {
-    _VSTD::__debug_db_insert_c(this);
     for (const_iterator __i = __c.begin(), __e = __c.end(); __i != __e; ++__i)
         push_back(*__i);
 }
 
 #ifndef _LIBCPP_CXX03_LANG
 
 template <class _Tp, class _Alloc>
 list<_Tp, _Alloc>::list(initializer_list<value_type> __il, const allocator_type& __a)
     : base(__a)
 {
-    _VSTD::__debug_db_insert_c(this);
     for (typename initializer_list<value_type>::const_iterator __i = __il.begin(),
             __e = __il.end(); __i != __e; ++__i)
         push_back(*__i);
 }
 
 template <class _Tp, class _Alloc>
 list<_Tp, _Alloc>::list(initializer_list<value_type> __il)
 {
-    _VSTD::__debug_db_insert_c(this);
     for (typename initializer_list<value_type>::const_iterator __i = __il.begin(),
             __e = __il.end(); __i != __e; ++__i)
         push_back(*__i);
 }
 
 template <class _Tp, class _Alloc>
 inline list<_Tp, _Alloc>::list(list&& __c)
         _NOEXCEPT_(is_nothrow_move_constructible<__node_allocator>::value)
         : base(_VSTD::move(__c.__node_alloc())) {
-    _VSTD::__debug_db_insert_c(this);
     splice(end(), __c);
 }
 
 template <class _Tp, class _Alloc>
 inline
 list<_Tp, _Alloc>::list(list&& __c, const __type_identity_t<allocator_type>& __a)
     : base(__a)
 {
-    _VSTD::__debug_db_insert_c(this);
     if (__a == __c.get_allocator())
         splice(end(), __c);
     else
     {
         typedef move_iterator<iterator> _Ip;
         assign(_Ip(__c.begin()), _Ip(__c.end()));
     }
 }
list<_Tp, _Alloc>::assign(_InpIter __f, _InpIter __l,
     iterator __i = begin();
     iterator __e = end();
     for (; __f != __l && __i != __e; ++__f, (void) ++__i)
         *__i = *__f;
     if (__i == __e)
         insert(__e, __f, __l);
     else
         erase(__i, __e);
-    std::__debug_db_invalidate_all(this);
 }
 
 template <class _Tp, class _Alloc>
 void
 list<_Tp, _Alloc>::assign(size_type __n, const value_type& __x)
 {
     iterator __i = begin();
     iterator __e = end();
     for (; __n > 0 && __i != __e; --__n, (void) ++__i)
         *__i = __x;
     if (__i == __e)
         insert(__e, __n, __x);
     else
         erase(__i, __e);
-    std::__debug_db_invalidate_all(this);
 }
 
 template <class _Tp, class _Alloc>
 inline
 _Alloc
 list<_Tp, _Alloc>::get_allocator() const _NOEXCEPT
 {
     return allocator_type(base::__node_alloc());
 }
 
 template <class _Tp, class _Alloc>
 typename list<_Tp, _Alloc>::iterator
 list<_Tp, _Alloc>::insert(const_iterator __p, const value_type& __x)
 {
-    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(_VSTD::addressof(__p)) == this,
-                         "list::insert(iterator, x) called with an iterator not referring to this list");
     __node_allocator& __na = base::__node_alloc();
     __hold_pointer __hold = __allocate_node(__na);
     __node_alloc_traits::construct(__na, _VSTD::addressof(__hold->__value_), __x);
     __link_nodes(__p.__ptr_, __hold->__as_link(), __hold->__as_link());
     ++base::__sz();
-    return iterator(__hold.release()->__as_link(), this);
+    return iterator(__hold.release()->__as_link());
 }
 
 template <class _Tp, class _Alloc>
 typename list<_Tp, _Alloc>::iterator
 list<_Tp, _Alloc>::insert(const_iterator __p, size_type __n, const value_type& __x)
 {
-    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(_VSTD::addressof(__p)) == this,
-                         "list::insert(iterator, n, x) called with an iterator not referring to this list");
-    iterator __r(__p.__ptr_, this);
+    iterator __r(__p.__ptr_);
     if (__n > 0)
     {
         size_type __ds = 0;
         __node_allocator& __na = base::__node_alloc();
         __hold_pointer __hold = __allocate_node(__na);
         __node_alloc_traits::construct(__na, _VSTD::addressof(__hold->__value_), __x);
         ++__ds;
-        __r = iterator(__hold->__as_link(), this);
+        __r = iterator(__hold->__as_link());
         __hold.release();
         iterator __e = __r;
 #ifndef _LIBCPP_HAS_NO_EXCEPTIONS
         try
         {
 #endif // _LIBCPP_HAS_NO_EXCEPTIONS
             for (--__n; __n != 0; --__n, (void) ++__e, ++__ds)
             {
#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
         {
             while (true)
             {
                 __node_alloc_traits::destroy(__na, _VSTD::addressof(*__e));
                 __link_pointer __prev = __e.__ptr_->__prev_;
                 __node_alloc_traits::deallocate(__na, __e.__ptr_->__as_node(), 1);
                 if (__prev == 0)
                     break;
-                __e = iterator(__prev, this);
+                __e = iterator(__prev);
             }
             throw;
         }
 #endif // _LIBCPP_HAS_NO_EXCEPTIONS
         __link_nodes(__p.__ptr_, __r.__ptr_, __e.__ptr_);
         base::__sz() += __ds;
     }
     return __r;
 }
 
 template <class _Tp, class _Alloc>
 template <class _InpIter>
 typename list<_Tp, _Alloc>::iterator
 list<_Tp, _Alloc>::insert(const_iterator __p, _InpIter __f, _InpIter __l,
                           __enable_if_t<__has_input_iterator_category<_InpIter>::value>*)
 {
-    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(_VSTD::addressof(__p)) == this,
-                         "list::insert(iterator, range) called with an iterator not referring to this list");
-    iterator __r(__p.__ptr_, this);
+    iterator __r(__p.__ptr_);
     if (__f != __l)
     {
         size_type __ds = 0;
         __node_allocator& __na = base::__node_alloc();
         __hold_pointer __hold = __allocate_node(__na);
         __node_alloc_traits::construct(__na, _VSTD::addressof(__hold->__value_), *__f);
         ++__ds;
-        __r = iterator(__hold.get()->__as_link(), this);
+        __r = iterator(__hold.get()->__as_link());
         __hold.release();
         iterator __e = __r;
 #ifndef _LIBCPP_HAS_NO_EXCEPTIONS
         try
         {
 #endif // _LIBCPP_HAS_NO_EXCEPTIONS
             for (++__f; __f != __l; ++__f, (void) ++__e, ++__ds)
             {
#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
         {
             while (true)
             {
                 __node_alloc_traits::destroy(__na, _VSTD::addressof(*__e));
                 __link_pointer __prev = __e.__ptr_->__prev_;
                 __node_alloc_traits::deallocate(__na, __e.__ptr_->__as_node(), 1);
                 if (__prev == 0)
                     break;
-                __e = iterator(__prev, this);
+                __e = iterator(__prev);
             }
             throw;
         }
 #endif // _LIBCPP_HAS_NO_EXCEPTIONS
         __link_nodes(__p.__ptr_, __r.__ptr_, __e.__ptr_);
         base::__sz() += __ds;
     }
     return __r;

 #endif
 }
 
 template <class _Tp, class _Alloc>
 template <class... _Args>
 typename list<_Tp, _Alloc>::iterator
 list<_Tp, _Alloc>::emplace(const_iterator __p, _Args&&... __args)
 {
-    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(_VSTD::addressof(__p)) == this,
-                         "list::emplace(iterator, args...) called with an iterator not referring to this list");
     __node_allocator& __na = base::__node_alloc();
     __hold_pointer __hold = __allocate_node(__na);
     __node_alloc_traits::construct(__na, _VSTD::addressof(__hold->__value_), _VSTD::forward<_Args>(__args)...);
     __link_pointer __nl = __hold.get()->__as_link();
     __link_nodes(__p.__ptr_, __nl, __nl);
     ++base::__sz();
     __hold.release();
-    return iterator(__nl, this);
+    return iterator(__nl);
 }
 
 template <class _Tp, class _Alloc>
 typename list<_Tp, _Alloc>::iterator
 list<_Tp, _Alloc>::insert(const_iterator __p, value_type&& __x)
 {
-    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(_VSTD::addressof(__p)) == this,
-                         "list::insert(iterator, x) called with an iterator not referring to this list");
     __node_allocator& __na = base::__node_alloc();
     __hold_pointer __hold = __allocate_node(__na);
     __node_alloc_traits::construct(__na, _VSTD::addressof(__hold->__value_), _VSTD::move(__x));
     __link_pointer __nl = __hold->__as_link();
     __link_nodes(__p.__ptr_, __nl, __nl);
     ++base::__sz();
     __hold.release();
-    return iterator(__nl, this);
+    return iterator(__nl);
 }
 
 #endif // _LIBCPP_CXX03_LANG
 
 template <class _Tp, class _Alloc>
 void
 list<_Tp, _Alloc>::pop_front()
 {
     _LIBCPP_ASSERT(!empty(), "list::pop_front() called with empty list");
     __node_allocator& __na = base::__node_alloc();
     __link_pointer __n = base::__end_.__next_;
     base::__unlink_nodes(__n, __n);
     --base::__sz();
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-    __c_node* __c = __get_db()->__find_c_and_lock(this);
-    for (__i_node** __p = __c->end_; __p != __c->beg_; )
-    {
-        --__p;
-        iterator* __i = static_cast<iterator*>((*__p)->__i_);
-        if (__i->__ptr_ == __n)
-        {
-            (*__p)->__c_ = nullptr;
-            if (--__c->end_ != __p)
-                _VSTD::memmove(__p, __p+1, (__c->end_ - __p)*sizeof(__i_node*));
-        }
-    }
-    __get_db()->unlock();
-#endif
     __node_pointer __np = __n->__as_node();
     __node_alloc_traits::destroy(__na, _VSTD::addressof(__np->__value_));
     __node_alloc_traits::deallocate(__na, __np, 1);
 }
 
 template <class _Tp, class _Alloc>
 void
 list<_Tp, _Alloc>::pop_back()
 {
     _LIBCPP_ASSERT(!empty(), "list::pop_back() called on an empty list");
     __node_allocator& __na = base::__node_alloc();
     __link_pointer __n = base::__end_.__prev_;
     base::__unlink_nodes(__n, __n);
     --base::__sz();
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-    __c_node* __c = __get_db()->__find_c_and_lock(this);
-    for (__i_node** __p = __c->end_; __p != __c->beg_; )
-    {
-        --__p;
-        iterator* __i = static_cast<iterator*>((*__p)->__i_);
-        if (__i->__ptr_ == __n)
-        {
-            (*__p)->__c_ = nullptr;
-            if (--__c->end_ != __p)
-                _VSTD::memmove(__p, __p+1, (__c->end_ - __p)*sizeof(__i_node*));
-        }
-    }
-    __get_db()->unlock();
-#endif
     __node_pointer __np = __n->__as_node();
     __node_alloc_traits::destroy(__na, _VSTD::addressof(__np->__value_));
     __node_alloc_traits::deallocate(__na, __np, 1);
 }
 
 template <class _Tp, class _Alloc>
 typename list<_Tp, _Alloc>::iterator
 list<_Tp, _Alloc>::erase(const_iterator __p)
 {
-    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(_VSTD::addressof(__p)) == this,
-                         "list::erase(iterator) called with an iterator not referring to this list");
     _LIBCPP_ASSERT(__p != end(),
         "list::erase(iterator) called with a non-dereferenceable iterator");
     __node_allocator& __na = base::__node_alloc();
     __link_pointer __n = __p.__ptr_;
     __link_pointer __r = __n->__next_;
     base::__unlink_nodes(__n, __n);
     --base::__sz();
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-    __c_node* __c = __get_db()->__find_c_and_lock(this);
-    for (__i_node** __ip = __c->end_; __ip != __c->beg_; )
-    {
-        --__ip;
-        iterator* __i = static_cast<iterator*>((*__ip)->__i_);
-        if (__i->__ptr_ == __n)
-        {
-            (*__ip)->__c_ = nullptr;
-            if (--__c->end_ != __ip)
-                _VSTD::memmove(__ip, __ip+1, (__c->end_ - __ip)*sizeof(__i_node*));
-        }
-    }
-    __get_db()->unlock();
-#endif
     __node_pointer __np = __n->__as_node();
     __node_alloc_traits::destroy(__na, _VSTD::addressof(__np->__value_));
     __node_alloc_traits::deallocate(__na, __np, 1);
-    return iterator(__r, this);
+    return iterator(__r);
 }
 
 template <class _Tp, class _Alloc>
 typename list<_Tp, _Alloc>::iterator
 list<_Tp, _Alloc>::erase(const_iterator __f, const_iterator __l)
 {
-    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(_VSTD::addressof(__f)) == this,
-                         "list::erase(iterator, iterator) called with an iterator not referring to this list");
-    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(_VSTD::addressof(__l)) == this,
-                         "list::erase(iterator, iterator) called with an iterator not referring to this list");
     if (__f != __l)
     {
         __node_allocator& __na = base::__node_alloc();
         base::__unlink_nodes(__f.__ptr_, __l.__ptr_->__prev_);
         while (__f != __l)
         {
             __link_pointer __n = __f.__ptr_;
             ++__f;
             --base::__sz();
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-            __c_node* __c = __get_db()->__find_c_and_lock(this);
-            for (__i_node** __p = __c->end_; __p != __c->beg_; )
-            {
-                --__p;
-                iterator* __i = static_cast<iterator*>((*__p)->__i_);
-                if (__i->__ptr_ == __n)
-                {
-                    (*__p)->__c_ = nullptr;
-                    if (--__c->end_ != __p)
-                        _VSTD::memmove(__p, __p+1, (__c->end_ - __p)*sizeof(__i_node*));
-                }
-            }
-            __get_db()->unlock();
-#endif
             __node_pointer __np = __n->__as_node();
             __node_alloc_traits::destroy(__na, _VSTD::addressof(__np->__value_));
             __node_alloc_traits::deallocate(__na, __np, 1);
         }
     }
-    return iterator(__l.__ptr_, this);
+    return iterator(__l.__ptr_);
 }
 
 template <class _Tp, class _Alloc>
 void
 list<_Tp, _Alloc>::resize(size_type __n)
 {
     if (__n < base::__sz())
         erase(__iterator(__n), end());
     else if (__n > base::__sz())
     {
         __n -= base::__sz();
         size_type __ds = 0;
         __node_allocator& __na = base::__node_alloc();
         __hold_pointer __hold = __allocate_node(__na);
         __node_alloc_traits::construct(__na, _VSTD::addressof(__hold->__value_));
         ++__ds;
-        iterator __r = iterator(__hold.release()->__as_link(), this);
+        iterator __r = iterator(__hold.release()->__as_link());
         iterator __e = __r;
 #ifndef _LIBCPP_HAS_NO_EXCEPTIONS
         try
         {
 #endif // _LIBCPP_HAS_NO_EXCEPTIONS
             for (--__n; __n != 0; --__n, (void) ++__e, ++__ds)
             {
                 __hold.reset(__node_alloc_traits::allocate(__na, 1));
                 __node_alloc_traits::construct(__na, _VSTD::addressof(__hold->__value_));
                 __e.__ptr_->__next_ = __hold.get()->__as_link();
                 __hold->__prev_ = __e.__ptr_;
                 __hold.release();
             }
 #ifndef _LIBCPP_HAS_NO_EXCEPTIONS
         }
         catch (...)
         {
             while (true)
             {
                 __node_alloc_traits::destroy(__na, _VSTD::addressof(*__e));
                 __link_pointer __prev = __e.__ptr_->__prev_;
                 __node_alloc_traits::deallocate(__na, __e.__ptr_->__as_node(), 1);
                 if (__prev == 0)
                     break;
-                __e = iterator(__prev, this);
+                __e = iterator(__prev);
             }
             throw;
         }
 #endif // _LIBCPP_HAS_NO_EXCEPTIONS
         __link_nodes_at_back(__r.__ptr_, __e.__ptr_);
         base::__sz() += __ds;
     }
 }
 
 template <class _Tp, class _Alloc>
 void
 list<_Tp, _Alloc>::resize(size_type __n, const value_type& __x)
 {
     if (__n < base::__sz())
         erase(__iterator(__n), end());
     else if (__n > base::__sz())
     {
         __n -= base::__sz();
         size_type __ds = 0;
         __node_allocator& __na = base::__node_alloc();
         __hold_pointer __hold = __allocate_node(__na);
         __node_alloc_traits::construct(__na, _VSTD::addressof(__hold->__value_), __x);
         ++__ds;
         __link_pointer __nl = __hold.release()->__as_link();
-        iterator __r = iterator(__nl, this);
+        iterator __r = iterator(__nl);
         iterator __e = __r;
 #ifndef _LIBCPP_HAS_NO_EXCEPTIONS
         try
         {
 #endif // _LIBCPP_HAS_NO_EXCEPTIONS
             for (--__n; __n != 0; --__n, (void) ++__e, ++__ds)
             {
                 __hold.reset(__node_alloc_traits::allocate(__na, 1));
                 __node_alloc_traits::construct(__na, _VSTD::addressof(__hold->__value_), __x);
                 __e.__ptr_->__next_ = __hold.get()->__as_link();
                 __hold->__prev_ = __e.__ptr_;
                 __hold.release();
             }
 #ifndef _LIBCPP_HAS_NO_EXCEPTIONS
         }
         catch (...)
         {
             while (true)
             {
                 __node_alloc_traits::destroy(__na, _VSTD::addressof(*__e));
                 __link_pointer __prev = __e.__ptr_->__prev_;
                 __node_alloc_traits::deallocate(__na, __e.__ptr_->__as_node(), 1);
                 if (__prev == 0)
                     break;
-                __e = iterator(__prev, this);
+                __e = iterator(__prev);
             }
             throw;
         }
 #endif // _LIBCPP_HAS_NO_EXCEPTIONS
         __link_nodes(base::__end_as_link(), __r.__ptr_, __e.__ptr_);
         base::__sz() += __ds;
     }
 }
 
 template <class _Tp, class _Alloc>
 void
 list<_Tp, _Alloc>::splice(const_iterator __p, list& __c)
 {
     _LIBCPP_ASSERT(this != _VSTD::addressof(__c),
                    "list::splice(iterator, list) called with this == &list");
-    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(_VSTD::addressof(__p)) == this,
-                         "list::splice(iterator, list) called with an iterator not referring to this list");
     if (!__c.empty())
     {
         __link_pointer __f = __c.__end_.__next_;
         __link_pointer __l = __c.__end_.__prev_;
         base::__unlink_nodes(__f, __l);
         __link_nodes(__p.__ptr_, __f, __l);
         base::__sz() += __c.__sz();
         __c.__sz() = 0;
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-        if (_VSTD::addressof(__c) != this) {
-            __libcpp_db* __db = __get_db();
-            __c_node* __cn1 = __db->__find_c_and_lock(this);
-            __c_node* __cn2 = __db->__find_c(_VSTD::addressof(__c));
-            for (__i_node** __ip = __cn2->end_; __ip != __cn2->beg_;)
-            {
-                --__ip;
-                iterator* __i = static_cast<iterator*>((*__ip)->__i_);
-                if (__i->__ptr_ != __c.__end_as_link())
-                {
-                    __cn1->__add(*__ip);
-                    (*__ip)->__c_ = __cn1;
-                    if (--__cn2->end_ != __ip)
-                        _VSTD::memmove(__ip, __ip+1, (__cn2->end_ - __ip)*sizeof(__i_node*));
-                }
-            }
-            __db->unlock();
-        }
-#endif
     }
 }
 
 template <class _Tp, class _Alloc>
 void
 list<_Tp, _Alloc>::splice(const_iterator __p, list& __c, const_iterator __i)
 {
-    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(_VSTD::addressof(__p)) == this,
-        "list::splice(iterator, list, iterator) called with the first iterator not referring to this list");
-    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(_VSTD::addressof(__i)) == _VSTD::addressof(__c),
-        "list::splice(iterator, list, iterator) called with the second iterator not referring to the list argument");
-    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__dereferenceable(_VSTD::addressof(__i)),
-        "list::splice(iterator, list, iterator) called with the second iterator not dereferenceable");
-
     if (__p.__ptr_ != __i.__ptr_ && __p.__ptr_ != __i.__ptr_->__next_)
     {
         __link_pointer __f = __i.__ptr_;
         base::__unlink_nodes(__f, __f);
         __link_nodes(__p.__ptr_, __f, __f);
         --__c.__sz();
         ++base::__sz();
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-        if (_VSTD::addressof(__c) != this) {
-            __libcpp_db* __db = __get_db();
-            __c_node* __cn1 = __db->__find_c_and_lock(this);
-            __c_node* __cn2 = __db->__find_c(_VSTD::addressof(__c));
-            for (__i_node** __ip = __cn2->end_; __ip != __cn2->beg_;)
-            {
-                --__ip;
-                iterator* __j = static_cast<iterator*>((*__ip)->__i_);
-                if (__j->__ptr_ == __f)
-                {
-                    __cn1->__add(*__ip);
-                    (*__ip)->__c_ = __cn1;
-                    if (--__cn2->end_ != __ip)
-                        _VSTD::memmove(__ip, __ip+1, (__cn2->end_ - __ip)*sizeof(__i_node*));
-                }
-            }
-            __db->unlock();
-        }
-#endif
     }
 }
 
 template <class _Iterator>
 _LIBCPP_HIDE_FROM_ABI
 bool __iterator_in_range(_Iterator __first, _Iterator __last, _Iterator __it) {
     for (_Iterator __p = __first; __p != __last; ++__p) {
         if (__p == __it) {
             return true;
         }
     }
     return false;
 }
 
 template <class _Tp, class _Alloc>
 void
 list<_Tp, _Alloc>::splice(const_iterator __p, list& __c, const_iterator __f, const_iterator __l)
 {
-    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(_VSTD::addressof(__p)) == this,
-        "list::splice(iterator, list, iterator, iterator) called with first iterator not referring to this list");
-    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(_VSTD::addressof(__f)) == _VSTD::addressof(__c),
-        "list::splice(iterator, list, iterator, iterator) called with second iterator not referring to the list argument");
-    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(_VSTD::addressof(__l)) == _VSTD::addressof(__c),
-        "list::splice(iterator, list, iterator, iterator) called with third iterator not referring to the list argument");
-    _LIBCPP_DEBUG_ASSERT(this != std::addressof(__c) || !std::__iterator_in_range(__f, __l, __p),
-        "list::splice(iterator, list, iterator, iterator)"
-        " called with the first iterator within the range of the second and third iterators");
-
     if (__f != __l)
     {
         __link_pointer __first = __f.__ptr_;
         --__l;
         __link_pointer __last = __l.__ptr_;
         if (this != _VSTD::addressof(__c))
         {
             size_type __s = _VSTD::distance(__f, __l) + 1;
             __c.__sz() -= __s;
             base::__sz() += __s;
         }
         base::__unlink_nodes(__first, __last);
         __link_nodes(__p.__ptr_, __first, __last);
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-        if (_VSTD::addressof(__c) != this) {
-            __libcpp_db* __db = __get_db();
-            __c_node* __cn1 = __db->__find_c_and_lock(this);
-            __c_node* __cn2 = __db->__find_c(_VSTD::addressof(__c));
-            for (__i_node** __ip = __cn2->end_; __ip != __cn2->beg_;)
-            {
-                --__ip;
-                iterator* __j = static_cast<iterator*>((*__ip)->__i_);
-                for (__link_pointer __k = __f.__ptr_;
-                                              __k != __l.__ptr_; __k = __k->__next_)
-                {
-                    if (__j->__ptr_ == __k)
-                    {
-                        __cn1->__add(*__ip);
-                        (*__ip)->__c_ = __cn1;
-                        if (--__cn2->end_ != __ip)
-                            _VSTD::memmove(__ip, __ip+1, (__cn2->end_ - __ip)*sizeof(__i_node*));
-                    }
-                }
-            }
-            __db->unlock();
-        }
-#endif
     }
 }
 
 template <class _Tp, class _Alloc>
 typename list<_Tp, _Alloc>::__remove_return_type
 list<_Tp, _Alloc>::remove(const value_type& __x)
 {
     list<_Tp, _Alloc> __deleted_nodes(get_allocator()); // collect the nodes we're removing
if (this != _VSTD::addressof(__c))
                 __m2 = _VSTD::next(__f1);
                 __link_nodes(__f1.__ptr_, __f, __l);
                 __f1 = __m2;
             }
             else
                 ++__f1;
         }
         splice(__e1, __c);
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-        __libcpp_db* __db = __get_db();
-        __c_node* __cn1 = __db->__find_c_and_lock(this);
-        __c_node* __cn2 = __db->__find_c(_VSTD::addressof(__c));
-        for (__i_node** __p = __cn2->end_; __p != __cn2->beg_;)
-        {
-            --__p;
-            iterator* __i = static_cast<iterator*>((*__p)->__i_);
-            if (__i->__ptr_ != __c.__end_as_link())
-            {
-                __cn1->__add(*__p);
-                (*__p)->__c_ = __cn1;
-                if (--__cn2->end_ != __p)
-                    _VSTD::memmove(__p, __p+1, (__cn2->end_ - __p)*sizeof(__i_node*));
-            }
-        }
-        __db->unlock();
-#endif
     }
 }
 
 template <class _Tp, class _Alloc>
 inline
 void
 list<_Tp, _Alloc>::sort()
 {

 
 template <class _Tp, class _Alloc>
 bool
 list<_Tp, _Alloc>::__invariants() const
 {
     return size() == _VSTD::distance(begin(), end());
 }
 
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-
-template <class _Tp, class _Alloc>
-bool
-list<_Tp, _Alloc>::__dereferenceable(const const_iterator* __i) const
-{
-    return __i->__ptr_ != this->__end_as_link();
-}
-
-template <class _Tp, class _Alloc>
-bool
-list<_Tp, _Alloc>::__decrementable(const const_iterator* __i) const
-{
-    return !empty() &&  __i->__ptr_ != base::__end_.__next_;
-}
-
-template <class _Tp, class _Alloc>
-bool
-list<_Tp, _Alloc>::__addable(const const_iterator*, ptrdiff_t) const
-{
-    return false;
-}
-
-template <class _Tp, class _Alloc>
-bool
-list<_Tp, _Alloc>::__subscriptable(const const_iterator*, ptrdiff_t) const
-{
-    return false;
-}
-
-#endif // _LIBCPP_ENABLE_DEBUG_MODE
-
 template <class _Tp, class _Alloc>
 inline _LIBCPP_INLINE_VISIBILITY
 bool
 operator==(const list<_Tp, _Alloc>& __x, const list<_Tp, _Alloc>& __y)
 {
     return __x.size() == __y.size() && _VSTD::equal(__x.begin(), __x.end(), __y.begin());
 }
 

libcxx/include/locale

 #include <__algorithm/copy.h>
 #include <__algorithm/equal.h>
 #include <__algorithm/find.h>
 #include <__algorithm/max.h>
 #include <__algorithm/reverse.h>
 #include <__algorithm/unwrap_iter.h>
 #include <__assert> // all public C++ headers provide the assertion handler
 #include <__config>
-#include <__debug>
 #include <__iterator/access.h>
 #include <__iterator/back_insert_iterator.h>
 #include <__iterator/istreambuf_iterator.h>
 #include <__iterator/ostreambuf_iterator.h>
 #include <__locale>
 #include <__memory/unique_ptr.h>
 #include <__type_traits/make_unsigned.h>
 #include <cerrno>

 _OutputIterator
 num_put<_CharT, _OutputIterator>::do_put(iter_type __s, ios_base& __iob,
                                          char_type __fl, bool __v) const
 {
     if ((__iob.flags() & ios_base::boolalpha) == 0)
         return do_put(__s, __iob, __fl, (unsigned long)__v);
     const numpunct<char_type>& __np = std::use_facet<numpunct<char_type> >(__iob.getloc());
     typedef typename numpunct<char_type>::string_type string_type;
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-    string_type __tmp(__v ? __np.truename() : __np.falsename());
-    string_type __nm = _VSTD::move(__tmp);
-#else
     string_type __nm = __v ? __np.truename() : __np.falsename();
-#endif
     for (typename string_type::iterator __i = __nm.begin(); __i != __nm.end(); ++__i, ++__s)
         *__s = *__i;
     return __s;
 }
 
 template <class _CharT, class _OutputIterator>
 template <class _Integral>
 _LIBCPP_HIDE_FROM_ABI inline

libcxx/include/module.modulemap.in

module version {
     header "version"
     export *
   }
 
   // FIXME: These should be private.
   module __assert            {         header "__assert"            export * }
   module __availability      { private header "__availability"      export * }
   module __bit_reference     { private header "__bit_reference"     export * }
-  module __debug             {         header "__debug"             export * }
   module __hash_table        {         header "__hash_table"        export * }
   module __locale            {
     @requires_LIBCXX_ENABLE_LOCALIZATION@
     private header "__locale" export *
   }
   module __mbstate_t         { private header "__mbstate_t.h"       export * }
   module __node_handle       { private header "__node_handle"       export * }
   module __split_buffer      { private header "__split_buffer"      export * }

libcxx/include/span

template<class R>
     span(R&&) -> span<remove_reference_t<ranges::range_reference_t<R>>>;
 
 } // namespace std
 
 */
 
 #include <__assert> // all public C++ headers provide the assertion handler
 #include <__config>
-#include <__debug>
 #include <__fwd/span.h>
 #include <__iterator/bounded_iter.h>
 #include <__iterator/concepts.h>
 #include <__iterator/iterator_traits.h>
 #include <__iterator/wrap_iter.h>
 #include <__memory/pointer_traits.h>
 #include <__ranges/concepts.h>
 #include <__ranges/data.h>
//  ~span() noexcept = default;
 
     _LIBCPP_INLINE_VISIBILITY constexpr pointer data()                         const noexcept { return __data_; }
 
 // [span.iter], span iterator support
     _LIBCPP_INLINE_VISIBILITY constexpr iterator begin() const noexcept {
 #ifdef _LIBCPP_DEBUG_ITERATOR_BOUNDS_CHECKING
         return std::__make_bounded_iter(data(), data(), data() + size());
 #else
-        return iterator(this, data());
+        return iterator(data());
 #endif
     }
     _LIBCPP_INLINE_VISIBILITY constexpr iterator end() const noexcept {
 #ifdef _LIBCPP_DEBUG_ITERATOR_BOUNDS_CHECKING
         return std::__make_bounded_iter(data() + size(), data(), data() + size());
 #else
-        return iterator(this, data() + size());
+        return iterator(data() + size());
 #endif
     }
     _LIBCPP_INLINE_VISIBILITY constexpr reverse_iterator        rbegin() const noexcept { return reverse_iterator(end()); }
     _LIBCPP_INLINE_VISIBILITY constexpr reverse_iterator          rend() const noexcept { return reverse_iterator(begin()); }
 
     _LIBCPP_INLINE_VISIBILITY span<const byte, _Extent * sizeof(element_type)> __as_bytes() const noexcept
     { return span<const byte, _Extent * sizeof(element_type)>{reinterpret_cast<const byte *>(data()), size_bytes()}; }
 
//    ~span() noexcept = default;
 
     _LIBCPP_INLINE_VISIBILITY constexpr pointer data()                         const noexcept { return __data_; }
 
 // [span.iter], span iterator support
     _LIBCPP_INLINE_VISIBILITY constexpr iterator begin() const noexcept {
 #ifdef _LIBCPP_DEBUG_ITERATOR_BOUNDS_CHECKING
         return std::__make_bounded_iter(data(), data(), data() + size());
 #else
-        return iterator(this, data());
+        return iterator(data());
 #endif
     }
     _LIBCPP_INLINE_VISIBILITY constexpr iterator end() const noexcept {
 #ifdef _LIBCPP_DEBUG_ITERATOR_BOUNDS_CHECKING
         return std::__make_bounded_iter(data() + size(), data(), data() + size());
 #else
-        return iterator(this, data() + size());
+        return iterator(data() + size());
 #endif
     }
     _LIBCPP_INLINE_VISIBILITY constexpr reverse_iterator        rbegin() const noexcept { return reverse_iterator(end()); }
     _LIBCPP_INLINE_VISIBILITY constexpr reverse_iterator          rend() const noexcept { return reverse_iterator(begin()); }
 
     _LIBCPP_INLINE_VISIBILITY span<const byte, dynamic_extent> __as_bytes() const noexcept
     { return {reinterpret_cast<const byte *>(data()), size_bytes()}; }
 

libcxx/include/string

 */
 
 #include <__algorithm/max.h>
 #include <__algorithm/min.h>
 #include <__algorithm/remove.h>
 #include <__algorithm/remove_if.h>
 #include <__assert> // all public C++ headers provide the assertion handler
 #include <__config>
-#include <__debug>
 #include <__format/enable_insertable.h>
 #include <__functional/hash.h>
 #include <__functional/unary_function.h>
 #include <__fwd/string.h>
 #include <__ios/fpos.h>
 #include <__iterator/distance.h>
 #include <__iterator/iterator_traits.h>
 #include <__iterator/reverse_iterator.h>
explicit basic_string(__uninitialized_size_tag, size_type __size, const allocator_type& __a)
         } else {
             auto __capacity = __recommend(__size) + 1;
             auto __allocation = __alloc_traits::allocate(__alloc(), __capacity);
             __begin_lifetime(__allocation, __capacity);
             __set_long_cap(__capacity);
             __set_long_pointer(__allocation);
             __set_long_size(__size);
         }
-        std::__debug_db_insert_c(this);
     }
 
     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 iterator __make_iterator(pointer __p) {
-        return iterator(this, __p);
+        return iterator(__p);
     }
 
     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 const_iterator __make_const_iterator(const_pointer __p) const {
-        return const_iterator(this, __p);
+        return const_iterator(__p);
     }
 
 public:
   _LIBCPP_TEMPLATE_DATA_VIS static const size_type npos = -1;
 
   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string()
       _NOEXCEPT_(is_nothrow_default_constructible<allocator_type>::value)
       : __r_(__default_init_tag(), __default_init_tag()) {
-    std::__debug_db_insert_c(this);
     __default_init();
   }
 
   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 explicit basic_string(const allocator_type& __a)
 #if _LIBCPP_STD_VER <= 14
       _NOEXCEPT_(is_nothrow_copy_constructible<allocator_type>::value)
 #else
       _NOEXCEPT
 #endif
       : __r_(__default_init_tag(), __a) {
-    std::__debug_db_insert_c(this);
     __default_init();
   }
 
   _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string(const basic_string& __str)
       : __r_(__default_init_tag(), __alloc_traits::select_on_container_copy_construction(__str.__alloc())) {
     if (!__str.__is_long())
       __r_.first() = __str.__r_.first();
     else
       __init_copy_ctor_external(std::__to_address(__str.__get_long_pointer()), __str.__get_long_size());
-    std::__debug_db_insert_c(this);
   }
 
   _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string(const basic_string& __str, const allocator_type& __a)
       : __r_(__default_init_tag(), __a) {
     if (!__str.__is_long())
       __r_.first() = __str.__r_.first();
     else
       __init_copy_ctor_external(std::__to_address(__str.__get_long_pointer()), __str.__get_long_size());
-    std::__debug_db_insert_c(this);
   }
 
 #ifndef _LIBCPP_CXX03_LANG
   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string(basic_string&& __str)
 #  if _LIBCPP_STD_VER <= 14
       _NOEXCEPT_(is_nothrow_move_constructible<allocator_type>::value)
 #  else
       _NOEXCEPT
 #  endif
       : __r_(std::move(__str.__r_)) {
     __str.__default_init();
-    std::__debug_db_insert_c(this);
-    if (__is_long())
-      std::__debug_db_swap(this, &__str);
   }
 
   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string(basic_string&& __str, const allocator_type& __a)
       : __r_(__default_init_tag(), __a) {
     if (__str.__is_long() && __a != __str.__alloc()) // copy, not move
       __init(std::__to_address(__str.__get_long_pointer()), __str.__get_long_size());
     else {
       if (__libcpp_is_constant_evaluated())
         __r_.first() = __rep();
       __r_.first() = __str.__r_.first();
       __str.__default_init();
     }
-    std::__debug_db_insert_c(this);
-    if (__is_long())
-      std::__debug_db_swap(this, &__str);
   }
 #endif // _LIBCPP_CXX03_LANG
 
   template <__enable_if_t<__is_allocator<_Allocator>::value, int> = 0>
   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string(const _CharT* __s)
       : __r_(__default_init_tag(), __default_init_tag()) {
     _LIBCPP_ASSERT(__s != nullptr, "basic_string(const char*) detected nullptr");
     __init(__s, traits_type::length(__s));
-    std::__debug_db_insert_c(this);
   }
 
   template <__enable_if_t<__is_allocator<_Allocator>::value, int> = 0>
   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string(const _CharT* __s, const _Allocator& __a)
       : __r_(__default_init_tag(), __a) {
     _LIBCPP_ASSERT(__s != nullptr, "basic_string(const char*, allocator) detected nullptr");
     __init(__s, traits_type::length(__s));
-    std::__debug_db_insert_c(this);
   }
 
 #if _LIBCPP_STD_VER >= 23
   basic_string(nullptr_t) = delete;
 #endif
 
   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string(const _CharT* __s, size_type __n)
       : __r_(__default_init_tag(), __default_init_tag()) {
     _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "basic_string(const char*, n) detected nullptr");
     __init(__s, __n);
-    std::__debug_db_insert_c(this);
   }
 
   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
   basic_string(const _CharT* __s, size_type __n, const _Allocator& __a)
       : __r_(__default_init_tag(), __a) {
     _LIBCPP_ASSERT(__n == 0 || __s != nullptr, "basic_string(const char*, n, allocator) detected nullptr");
     __init(__s, __n);
-    std::__debug_db_insert_c(this);
   }
 
   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string(size_type __n, _CharT __c)
       : __r_(__default_init_tag(), __default_init_tag()) {
     __init(__n, __c);
-    std::__debug_db_insert_c(this);
   }
 
 #if _LIBCPP_STD_VER >= 23
   _LIBCPP_HIDE_FROM_ABI constexpr
   basic_string(basic_string&& __str, size_type __pos, const _Allocator& __alloc = _Allocator())
       : basic_string(std::move(__str), __pos, npos, __alloc) {}
 
   _LIBCPP_HIDE_FROM_ABI constexpr
if (__alloc_traits::is_always_equal::value || __alloc == __str.__alloc()) {
 
       _Traits::move(data(), data() + __pos, __len);
       __set_size(__len);
       _Traits::assign(data()[__len], value_type());
     } else {
       // Perform a copy because the allocators are not compatible.
       __init(__str.data() + __pos, __len);
     }
-
-    std::__debug_db_insert_c(this);
-    if (__is_long())
-      std::__debug_db_swap(this, &__str);
   }
 #endif
 
   template <__enable_if_t<__is_allocator<_Allocator>::value, int> = 0>
   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string(size_type __n, _CharT __c, const _Allocator& __a)
       : __r_(__default_init_tag(), __a) {
     __init(__n, __c);
-    std::__debug_db_insert_c(this);
   }
 
   _LIBCPP_CONSTEXPR_SINCE_CXX20
   basic_string(const basic_string& __str, size_type __pos, size_type __n, const _Allocator& __a = _Allocator())
       : __r_(__default_init_tag(), __a) {
     size_type __str_sz = __str.size();
     if (__pos > __str_sz)
       __throw_out_of_range();
     __init(__str.data() + __pos, std::min(__n, __str_sz - __pos));
-    std::__debug_db_insert_c(this);
   }
 
   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
   basic_string(const basic_string& __str, size_type __pos, const _Allocator& __a = _Allocator())
       : __r_(__default_init_tag(), __a) {
     size_type __str_sz = __str.size();
     if (__pos > __str_sz)
       __throw_out_of_range();
     __init(__str.data() + __pos, __str_sz - __pos);
-    std::__debug_db_insert_c(this);
   }
 
   template <class _Tp,
             __enable_if_t<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value &&
                               !__is_same_uncvref<_Tp, basic_string>::value,
                           int> = 0>
   _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS _LIBCPP_CONSTEXPR_SINCE_CXX20
   basic_string(const _Tp& __t, size_type __pos, size_type __n, const allocator_type& __a = allocator_type())
       : __r_(__default_init_tag(), __a) {
     __self_view __sv0 = __t;
     __self_view __sv  = __sv0.substr(__pos, __n);
     __init(__sv.data(), __sv.size());
-    std::__debug_db_insert_c(this);
   }
 
   template <class _Tp,
             __enable_if_t<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value &&
                               !__is_same_uncvref<_Tp, basic_string>::value,
                           int> = 0>
   _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS _LIBCPP_CONSTEXPR_SINCE_CXX20 explicit basic_string(const _Tp& __t)
       : __r_(__default_init_tag(), __default_init_tag()) {
     __self_view __sv = __t;
     __init(__sv.data(), __sv.size());
-    std::__debug_db_insert_c(this);
   }
 
   template <class _Tp,
             __enable_if_t<__can_be_converted_to_string_view<_CharT, _Traits, _Tp>::value &&
                               !__is_same_uncvref<_Tp, basic_string>::value,
                           int> = 0>
   _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS _LIBCPP_CONSTEXPR_SINCE_CXX20 explicit basic_string(
       const _Tp& __t, const allocator_type& __a)
       : __r_(__default_init_tag(), __a) {
     __self_view __sv = __t;
     __init(__sv.data(), __sv.size());
-    std::__debug_db_insert_c(this);
   }
 
   template <class _InputIterator, __enable_if_t<__has_input_iterator_category<_InputIterator>::value, int> = 0>
   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string(_InputIterator __first, _InputIterator __last)
       : __r_(__default_init_tag(), __default_init_tag()) {
     __init(__first, __last);
-    std::__debug_db_insert_c(this);
   }
 
   template <class _InputIterator, __enable_if_t<__has_input_iterator_category<_InputIterator>::value, int> = 0>
   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
   basic_string(_InputIterator __first, _InputIterator __last, const allocator_type& __a)
       : __r_(__default_init_tag(), __a) {
     __init(__first, __last);
-    std::__debug_db_insert_c(this);
   }
 
 #ifndef _LIBCPP_CXX03_LANG
   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string(initializer_list<_CharT> __il)
       : __r_(__default_init_tag(), __default_init_tag()) {
     __init(__il.begin(), __il.end());
-    std::__debug_db_insert_c(this);
   }
 
   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string(initializer_list<_CharT> __il, const _Allocator& __a)
       : __r_(__default_init_tag(), __a) {
     __init(__il.begin(), __il.end());
-    std::__debug_db_insert_c(this);
   }
 #endif // _LIBCPP_CXX03_LANG
 
   inline _LIBCPP_CONSTEXPR_SINCE_CXX20 ~basic_string() {
-    std::__debug_db_erase_c(this);
     if (__is_long())
       __alloc_traits::deallocate(__alloc(), __get_long_pointer(), __get_long_cap());
   }
 
     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
     operator __self_view() const _NOEXCEPT { return __self_view(data(), size()); }
 
     _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string& operator=(const basic_string& __str);
#endif // _LIBCPP_CXX03_LANG
   insert(size_type __pos1, const basic_string& __str, size_type __pos2, size_type __n = npos);
   _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string& insert(size_type __pos, const value_type* __s, size_type __n);
   _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string& insert(size_type __pos, const value_type* __s);
   _LIBCPP_CONSTEXPR_SINCE_CXX20 basic_string& insert(size_type __pos, size_type __n, value_type __c);
   _LIBCPP_CONSTEXPR_SINCE_CXX20 iterator insert(const_iterator __pos, value_type __c);
 
   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 iterator
   insert(const_iterator __pos, size_type __n, value_type __c) {
-    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(&__pos) == this,
-                         "string::insert(iterator, n, value) called with an iterator not referring to this string");
     difference_type __p = __pos - begin();
     insert(static_cast<size_type>(__p), __n, __c);
     return begin() + __p;
   }
 
   template <class _InputIterator, __enable_if_t<__has_exactly_input_iterator_category<_InputIterator>::value, int> = 0>
   _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS _LIBCPP_CONSTEXPR_SINCE_CXX20 iterator
   insert(const_iterator __pos, _InputIterator __first, _InputIterator __last);
#if _LIBCPP_STD_VER >= 23
     bool contains(const value_type* __s) const
     { return __self_view(data(), size()).contains(__s); }
 #endif
 
     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool __invariants() const;
 
     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __clear_and_shrink() _NOEXCEPT;
 
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-
-    bool __dereferenceable(const const_iterator* __i) const;
-    bool __decrementable(const const_iterator* __i) const;
-    bool __addable(const const_iterator* __i, ptrdiff_t __n) const;
-    bool __subscriptable(const const_iterator* __i, ptrdiff_t __n) const;
-
-#endif // _LIBCPP_ENABLE_DEBUG_MODE
-
 private:
     template<class _Alloc>
     inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
     bool friend operator==(const basic_string<char, char_traits<char>, _Alloc>& __lhs,
                            const basic_string<char, char_traits<char>, _Alloc>& __rhs) _NOEXCEPT;
 
     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __shrink_or_extend(size_type __target_capacity);
 
inline basic_string& __assign_short(const value_type* __s, size_type __n) {
       traits_type::move(std::__to_address(__p), __s, __n);
       traits_type::assign(__p[__n], value_type());
       return *this;
     }
 
     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
     basic_string& __null_terminate_at(value_type* __p, size_type __newsz) {
       __set_size(__newsz);
-      __invalidate_iterators_past(__newsz);
       traits_type::assign(__p[__newsz], value_type());
       return *this;
     }
 
-    _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void __invalidate_iterators_past(size_type);
-
     template <
         class _Tp,
         __enable_if_t<__is_less_than_comparable<const __remove_cvref_t<_Tp>*, const value_type*>::value, int> = 0>
     _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool __addr_in_range(const _Tp& __v) const {
       return std::__is_pointer_in_range(data(), data() + size() + 1, std::addressof(__v));
     }
 
     template <
template<class _CharT,
          class = enable_if_t<__is_allocator<_Allocator>::value>,
          class _Sz = typename allocator_traits<_Allocator>::size_type
          >
 basic_string(basic_string_view<_CharT, _Traits>, _Sz, _Sz, const _Allocator& = _Allocator())
   -> basic_string<_CharT, _Traits, _Allocator>;
 #endif
 
 template <class _CharT, class _Traits, class _Allocator>
-inline _LIBCPP_CONSTEXPR_SINCE_CXX20
-void
-basic_string<_CharT, _Traits, _Allocator>::__invalidate_iterators_past(size_type __pos)
-{
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-    if (!__libcpp_is_constant_evaluated()) {
-        __c_node* __c = __get_db()->__find_c_and_lock(this);
-        if (__c)
-        {
-            const_pointer __new_last = __get_pointer() + __pos;
-            for (__i_node** __p = __c->end_; __p != __c->beg_; )
-            {
-                --__p;
-                const_iterator* __i = static_cast<const_iterator*>((*__p)->__i_);
-                if (__i->base() > __new_last)
-                {
-                    (*__p)->__c_ = nullptr;
-                    if (--__c->end_ != __p)
-                        std::memmove(__p, __p+1, (__c->end_ - __p)*sizeof(__i_node*));
-                }
-            }
-            __get_db()->unlock();
-        }
-    }
-#else
-    (void)__pos;
-#endif // _LIBCPP_ENABLE_DEBUG_MODE
-}
-
-template <class _CharT, class _Traits, class _Allocator>
 _LIBCPP_CONSTEXPR_SINCE_CXX20
 void basic_string<_CharT, _Traits, _Allocator>::__init(const value_type* __s,
                                                        size_type __sz,
                                                        size_type __reserve)
 {
     if (__libcpp_is_constant_evaluated())
         __r_.first() = __rep();
     if (__reserve > max_size())
if (__delta_cap > __ms - __old_cap - 1)
         __throw_length_error();
     pointer __old_p = __get_pointer();
     size_type __cap = __old_cap < __ms / 2 - __alignment ?
                           __recommend(std::max(__old_cap + __delta_cap, 2 * __old_cap)) :
                           __ms - 1;
     auto __allocation = std::__allocate_at_least(__alloc(), __cap + 1);
     pointer __p = __allocation.ptr;
     __begin_lifetime(__p, __allocation.count);
-    std::__debug_db_invalidate_all(this);
     if (__n_copy != 0)
         traits_type::copy(std::__to_address(__p),
                           std::__to_address(__old_p), __n_copy);
     if (__n_add != 0)
         traits_type::copy(std::__to_address(__p) + __n_copy, __p_new_stuff, __n_add);
     size_type __sec_cp_sz = __old_sz - __n_del - __n_copy;
     if (__sec_cp_sz != 0)
         traits_type::copy(std::__to_address(__p) + __n_copy + __n_add,
if (__delta_cap > __ms - __old_cap)
         __throw_length_error();
     pointer __old_p = __get_pointer();
     size_type __cap = __old_cap < __ms / 2 - __alignment ?
                           __recommend(std::max(__old_cap + __delta_cap, 2 * __old_cap)) :
                           __ms - 1;
     auto __allocation = std::__allocate_at_least(__alloc(), __cap + 1);
     pointer __p = __allocation.ptr;
     __begin_lifetime(__p, __allocation.count);
-    std::__debug_db_invalidate_all(this);
     if (__n_copy != 0)
         traits_type::copy(std::__to_address(__p),
                           std::__to_address(__old_p), __n_copy);
     size_type __sec_cp_sz = __old_sz - __n_del - __n_copy;
     if (__sec_cp_sz != 0)
         traits_type::copy(std::__to_address(__p) + __n_copy + __n_add,
                           std::__to_address(__old_p) + __n_copy + __n_del,
                           __sec_cp_sz);

 basic_string<_CharT, _Traits, _Allocator>::__assign_no_alias(
     const value_type* __s, size_type __n) {
   size_type __cap = __is_short ? static_cast<size_type>(__min_cap) : __get_long_cap();
   if (__n < __cap) {
     pointer __p = __is_short ? __get_short_pointer() : __get_long_pointer();
     __is_short ? __set_short_size(__n) : __set_long_size(__n);
     traits_type::copy(std::__to_address(__p), __s, __n);
     traits_type::assign(__p[__n], value_type());
-    __invalidate_iterators_past(__n);
   } else {
     size_type __sz = __is_short ? __get_short_size() : __get_long_size();
     __grow_by_and_replace(__cap - 1, __n - __cap + 1, __sz, 0, __sz, __n, __s);
   }
   return *this;
 }
 
 template <class _CharT, class _Traits, class _Allocator>
basic_string<_CharT, _Traits, _Allocator>::operator=(value_type __c)
     }
     else
     {
         __p = __get_short_pointer();
         __set_short_size(1);
     }
     traits_type::assign(*__p, __c);
     traits_type::assign(*++__p, value_type());
-    __invalidate_iterators_past(1);
     return *this;
 }
 
 template <class _CharT, class _Traits, class _Allocator>
 _LIBCPP_CONSTEXPR_SINCE_CXX20
 basic_string<_CharT, _Traits, _Allocator>&
 basic_string<_CharT, _Traits, _Allocator>::operator=(const basic_string& __str)
 {
if (__string_is_trivial_iterator<_ForwardIterator>::value &&
             size_type __sz = size();
             __grow_by(__cap, __n - __cap, __sz, 0, __sz);
         }
         pointer __p = __get_pointer();
         for (; __first != __last; ++__p, (void) ++__first)
             traits_type::assign(*__p, *__first);
         traits_type::assign(*__p, value_type());
         __set_size(__n);
-        __invalidate_iterators_past(__n);
     }
     else
     {
         const basic_string __temp(__first, __last, __alloc());
         assign(__temp.data(), __temp.size());
     }
     return *this;
 }
basic_string<_CharT, _Traits, _Allocator>::insert(size_type __pos, size_type __n, value_type __c)
     return *this;
 }
 
 template <class _CharT, class _Traits, class _Allocator>
 template<class _InputIterator, __enable_if_t<__has_exactly_input_iterator_category<_InputIterator>::value, int> >
 _LIBCPP_CONSTEXPR_SINCE_CXX20 typename basic_string<_CharT, _Traits, _Allocator>::iterator
 basic_string<_CharT, _Traits, _Allocator>::insert(const_iterator __pos, _InputIterator __first, _InputIterator __last)
 {
-  _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(&__pos) == this,
-                       "string::insert(iterator, range) called with an iterator not"
-                       " referring to this string");
   const basic_string __temp(__first, __last, __alloc());
   return insert(__pos, __temp.data(), __temp.data() + __temp.size());
 }
 
 template <class _CharT, class _Traits, class _Allocator>
 template<class _ForwardIterator, __enable_if_t<__has_forward_iterator_category<_ForwardIterator>::value, int> >
 _LIBCPP_CONSTEXPR_SINCE_CXX20 typename basic_string<_CharT, _Traits, _Allocator>::iterator
 basic_string<_CharT, _Traits, _Allocator>::insert(const_iterator __pos, _ForwardIterator __first, _ForwardIterator __last)
 {
-    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(&__pos) == this,
-                         "string::insert(iterator, range) called with an iterator not referring to this string");
-
     size_type __ip = static_cast<size_type>(__pos - begin());
     size_type __n = static_cast<size_type>(std::distance(__first, __last));
     if (__n == 0)
         return begin() + __ip;
 
     if (__string_is_trivial_iterator<_ForwardIterator>::value && !__addr_in_range(*__first))
     {
         return __insert_from_safe_copy(__n, __ip, __first, __last);
basic_string<_CharT, _Traits, _Allocator>::insert(size_type __pos, const value_type* __s)
     return insert(__pos, __s, traits_type::length(__s));
 }
 
 template <class _CharT, class _Traits, class _Allocator>
 _LIBCPP_CONSTEXPR_SINCE_CXX20
 typename basic_string<_CharT, _Traits, _Allocator>::iterator
 basic_string<_CharT, _Traits, _Allocator>::insert(const_iterator __pos, value_type __c)
 {
-    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(&__pos) == this,
-                         "string::insert(iterator, character) called with an iterator not"
-                         " referring to this string");
-
     size_type __ip = static_cast<size_type>(__pos - begin());
     size_type __sz = size();
     size_type __cap = capacity();
     value_type* __p;
     if (__cap == __sz)
     {
         __grow_by(__cap, 1, __sz, __ip, 0, 1);
         __p = std::__to_address(__get_long_pointer());
basic_string<_CharT, _Traits, _Allocator>::erase(size_type __pos,
   return *this;
 }
 
 template <class _CharT, class _Traits, class _Allocator>
 inline _LIBCPP_CONSTEXPR_SINCE_CXX20
 typename basic_string<_CharT, _Traits, _Allocator>::iterator
 basic_string<_CharT, _Traits, _Allocator>::erase(const_iterator __pos)
 {
-  _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(&__pos) == this,
-                       "string::erase(iterator) called with an iterator not"
-                       " referring to this string");
-
   _LIBCPP_ASSERT(__pos != end(), "string::erase(iterator) called with a non-dereferenceable iterator");
   iterator __b = begin();
   size_type __r = static_cast<size_type>(__pos - __b);
   erase(__r, 1);
   return __b + static_cast<difference_type>(__r);
 }
 
 template <class _CharT, class _Traits, class _Allocator>
 inline _LIBCPP_CONSTEXPR_SINCE_CXX20
 typename basic_string<_CharT, _Traits, _Allocator>::iterator
 basic_string<_CharT, _Traits, _Allocator>::erase(const_iterator __first, const_iterator __last)
 {
-  _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(&__first) == this,
-                       "string::erase(iterator,  iterator) called with an iterator not"
-                       " referring to this string");
-
   _LIBCPP_ASSERT(__first <= __last, "string::erase(first, last) called with invalid range");
   iterator __b = begin();
   size_type __r = static_cast<size_type>(__first - __b);
   erase(__r, static_cast<size_type>(__last - __first));
   return __b + static_cast<difference_type>(__r);
 }
 
 template <class _CharT, class _Traits, class _Allocator>
 inline _LIBCPP_CONSTEXPR_SINCE_CXX20
 void
 basic_string<_CharT, _Traits, _Allocator>::pop_back()
 {
     _LIBCPP_ASSERT(!empty(), "string::pop_back(): string is already empty");
     __erase_to_end(size() - 1);
 }
 
 template <class _CharT, class _Traits, class _Allocator>
 inline _LIBCPP_CONSTEXPR_SINCE_CXX20
 void
 basic_string<_CharT, _Traits, _Allocator>::clear() _NOEXCEPT
 {
-    std::__debug_db_invalidate_all(this);
     if (__is_long())
     {
         traits_type::assign(*__get_long_pointer(), value_type());
         __set_long_size(0);
     }
     else
     {
         traits_type::assign(*__get_short_pointer(), value_type());
basic_string<_CharT, _Traits, _Allocator>::__shrink_or_extend(size_type __target_capacity)
     if (__now_long)
     {
         __set_long_cap(__target_capacity+1);
         __set_long_size(__sz);
         __set_long_pointer(__new_data);
     }
     else
         __set_short_size(__sz);
-    std::__debug_db_invalidate_all(this);
 }
 
 template <class _CharT, class _Traits, class _Allocator>
 _LIBCPP_CONSTEXPR_SINCE_CXX20
 typename basic_string<_CharT, _Traits, _Allocator>::const_reference
 basic_string<_CharT, _Traits, _Allocator>::at(size_type __n) const
 {
     if (__n >= size())

 basic_string<_CharT, _Traits, _Allocator>::swap(basic_string& __str)
 #if _LIBCPP_STD_VER >= 14
         _NOEXCEPT
 #else
         _NOEXCEPT_(!__alloc_traits::propagate_on_container_swap::value ||
                     __is_nothrow_swappable<allocator_type>::value)
 #endif
 {
-    if (!__is_long())
-        std::__debug_db_invalidate_all(this);
-    if (!__str.__is_long())
-        std::__debug_db_invalidate_all(&__str);
-    std::__debug_db_swap(this, &__str);
-
     _LIBCPP_ASSERT(
         __alloc_traits::propagate_on_container_swap::value ||
         __alloc_traits::is_always_equal::value ||
         __alloc() == __str.__alloc(), "swapping non-equal allocators");
     std::swap(__r_.first(), __str.__r_.first());
     std::__swap_allocator(__alloc(), __str.__alloc());
 }
 
erase_if(basic_string<_CharT, _Traits, _Allocator>& __str,
              _Predicate __pred) {
   auto __old_size = __str.size();
   __str.erase(std::remove_if(__str.begin(), __str.end(), __pred),
               __str.end());
   return __old_size - __str.size();
 }
 #endif
 
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-
-template<class _CharT, class _Traits, class _Allocator>
-bool
-basic_string<_CharT, _Traits, _Allocator>::__dereferenceable(const const_iterator* __i) const
-{
-    return data() <= std::__to_address(__i->base()) &&
-           std::__to_address(__i->base()) < data() + size();
-}
-
-template<class _CharT, class _Traits, class _Allocator>
-bool
-basic_string<_CharT, _Traits, _Allocator>::__decrementable(const const_iterator* __i) const
-{
-    return data() < std::__to_address(__i->base()) &&
-           std::__to_address(__i->base()) <= data() + size();
-}
-
-template<class _CharT, class _Traits, class _Allocator>
-bool
-basic_string<_CharT, _Traits, _Allocator>::__addable(const const_iterator* __i, ptrdiff_t __n) const
-{
-    const value_type* __p = std::__to_address(__i->base()) + __n;
-    return data() <= __p && __p <= data() + size();
-}
-
-template<class _CharT, class _Traits, class _Allocator>
-bool
-basic_string<_CharT, _Traits, _Allocator>::__subscriptable(const const_iterator* __i, ptrdiff_t __n) const
-{
-    const value_type* __p = std::__to_address(__i->base()) + __n;
-    return data() <= __p && __p < data() + size();
-}
-
-#endif // _LIBCPP_ENABLE_DEBUG_MODE
-
 #if _LIBCPP_STD_VER >= 14
 // Literal suffixes for basic_string [basic.string.literals]
 inline namespace literals
 {
   inline namespace string_literals
   {
     inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20
     basic_string<char> operator "" s( const char *__str, size_t __len )

libcxx/include/unordered_map

 }  // std
 
 */
 
 #include <__algorithm/is_permutation.h>
 #include <__assert> // all public C++ headers provide the assertion handler
 #include <__availability>
 #include <__config>
-#include <__debug>
 #include <__functional/is_transparent.h>
 #include <__functional/operations.h>
 #include <__hash_table>
 #include <__iterator/distance.h>
 #include <__iterator/erase_if_container.h>
 #include <__iterator/iterator_traits.h>
 #include <__memory/addressof.h>
 #include <__memory/allocator.h>
template <class _Key2, class _Tp2, class _Hash2, class _Pred2, class _Alloc2>
         friend class _LIBCPP_TEMPLATE_VIS unordered_map;
     template <class _Key2, class _Tp2, class _Hash2, class _Pred2, class _Alloc2>
         friend class _LIBCPP_TEMPLATE_VIS unordered_multimap;
 
     _LIBCPP_INLINE_VISIBILITY
     unordered_map()
         _NOEXCEPT_(is_nothrow_default_constructible<__table>::value)
     {
-        _VSTD::__debug_db_insert_c(this);
     }
     explicit _LIBCPP_HIDE_FROM_ABI unordered_map(size_type __n, const hasher& __hf = hasher(),
                            const key_equal& __eql = key_equal());
     _LIBCPP_HIDE_FROM_ABI unordered_map(size_type __n, const hasher& __hf,
                   const key_equal& __eql,
                   const allocator_type& __a);
     template <class _InputIterator>
     _LIBCPP_HIDE_FROM_ABI unordered_map(_InputIterator __first, _InputIterator __last);
#endif // _LIBCPP_CXX03_LANG
     const_iterator cbegin() const _NOEXCEPT {return __table_.begin();}
     _LIBCPP_INLINE_VISIBILITY
     const_iterator cend()   const _NOEXCEPT {return __table_.end();}
 
     _LIBCPP_INLINE_VISIBILITY
     pair<iterator, bool> insert(const value_type& __x)
         {return __table_.__insert_unique(__x);}
 
-    _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __p, const value_type& __x) {
-        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(_VSTD::addressof(__p)) == this,
-                             "unordered_map::insert(const_iterator, const value_type&) called with an iterator not "
-                             "referring to this unordered_map");
-        ((void)__p);
+    _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator, const value_type& __x) {
         return insert(__x).first;
     }
 
     template <class _InputIterator>
         _LIBCPP_INLINE_VISIBILITY
         void insert(_InputIterator __first, _InputIterator __last);
 
 #ifndef _LIBCPP_CXX03_LANG
     _LIBCPP_INLINE_VISIBILITY
     void insert(initializer_list<value_type> __il)
         {insert(__il.begin(), __il.end());}
 
     _LIBCPP_INLINE_VISIBILITY
     pair<iterator, bool> insert(value_type&& __x)
         {return __table_.__insert_unique(_VSTD::move(__x));}
 
-    _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator __p, value_type&& __x) {
-        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(_VSTD::addressof(__p)) == this,
-                             "unordered_map::insert(const_iterator, const value_type&) called with an iterator not"
-                             " referring to this unordered_map");
-        ((void)__p);
+    _LIBCPP_HIDE_FROM_ABI iterator insert(const_iterator, value_type&& __x) {
         return __table_.__insert_unique(_VSTD::move(__x)).first;
     }
 
     template <class _Pp,
               class = __enable_if_t<is_constructible<value_type, _Pp>::value> >
         _LIBCPP_INLINE_VISIBILITY
         pair<iterator, bool> insert(_Pp&& __x)
             {return __table_.__insert_unique(_VSTD::forward<_Pp>(__x));}
 
     template <class _Pp,
               class = __enable_if_t<is_constructible<value_type, _Pp>::value> >
         _LIBCPP_INLINE_VISIBILITY
-        iterator insert(const_iterator __p, _Pp&& __x)
+        iterator insert(const_iterator, _Pp&& __x)
         {
-            _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(_VSTD::addressof(__p)) == this,
-                                 "unordered_map::insert(const_iterator, value_type&&) called with an iterator not"
-                                 " referring to this unordered_map");
-          ((void)__p);
             return insert(_VSTD::forward<_Pp>(__x)).first;
         }
 
     template <class... _Args>
     _LIBCPP_INLINE_VISIBILITY
     pair<iterator, bool> emplace(_Args&&... __args) {
         return __table_.__emplace_unique(_VSTD::forward<_Args>(__args)...);
     }
 
     template <class... _Args>
     _LIBCPP_INLINE_VISIBILITY
-    iterator emplace_hint(const_iterator __p, _Args&&... __args) {
-        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(_VSTD::addressof(__p)) == this,
-                             "unordered_map::emplace_hint(const_iterator, args...) called with an iterator not"
-                             " referring to this unordered_map");
-          ((void)__p);
+    iterator emplace_hint(const_iterator, _Args&&... __args) {
         return __table_.__emplace_unique(_VSTD::forward<_Args>(__args)...).first;
     }
 
 #endif // _LIBCPP_CXX03_LANG
 
 #if _LIBCPP_STD_VER >= 17
     template <class... _Args>
         _LIBCPP_INLINE_VISIBILITY
#if _LIBCPP_STD_VER >= 17
     {
         return __table_.__emplace_unique_key_args(__k, piecewise_construct,
             _VSTD::forward_as_tuple(_VSTD::move(__k)),
             _VSTD::forward_as_tuple(_VSTD::forward<_Args>(__args)...));
     }
 
     template <class... _Args>
         _LIBCPP_INLINE_VISIBILITY
-        iterator try_emplace(const_iterator __h, const key_type& __k, _Args&&... __args)
+        iterator try_emplace(const_iterator, const key_type& __k, _Args&&... __args)
     {
-        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(_VSTD::addressof(__h)) == this,
-                             "unordered_map::try_emplace(const_iterator, key, args...) called with an iterator not"
-                             " referring to this unordered_map");
-        ((void)__h);
         return try_emplace(__k, _VSTD::forward<_Args>(__args)...).first;
     }
 
     template <class... _Args>
         _LIBCPP_INLINE_VISIBILITY
-        iterator try_emplace(const_iterator __h, key_type&& __k, _Args&&... __args)
+        iterator try_emplace(const_iterator, key_type&& __k, _Args&&... __args)
     {
-        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(_VSTD::addressof(__h)) == this,
-                             "unordered_map::try_emplace(const_iterator, key, args...) called with an iterator not"
-                             " referring to this unordered_map");
-        ((void)__h);
         return try_emplace(_VSTD::move(__k), _VSTD::forward<_Args>(__args)...).first;
     }
 
     template <class _Vp>
         _LIBCPP_INLINE_VISIBILITY
         pair<iterator, bool> insert_or_assign(const key_type& __k, _Vp&& __v)
     {
         pair<iterator, bool> __res = __table_.__emplace_unique_key_args(__k,
template <class _Vp>
         }
         return __res;
     }
 
     template <class _Vp>
         _LIBCPP_INLINE_VISIBILITY
         iterator insert_or_assign(const_iterator, const key_type& __k, _Vp&& __v)
      {
-          // FIXME: Add debug mode checking for the iterator input
           return insert_or_assign(__k, _VSTD::forward<_Vp>(__v)).first;
      }
 
     template <class _Vp>
         _LIBCPP_INLINE_VISIBILITY
         iterator insert_or_assign(const_iterator, key_type&& __k, _Vp&& __v)
      {
-        // FIXME: Add debug mode checking for the iterator input
         return insert_or_assign(_VSTD::move(__k), _VSTD::forward<_Vp>(__v)).first;
      }
 #endif // _LIBCPP_STD_VER >= 17
 
     _LIBCPP_INLINE_VISIBILITY
     iterator erase(const_iterator __p) {return __table_.erase(__p.__i_);}
     _LIBCPP_INLINE_VISIBILITY
     iterator erase(iterator __p)       {return __table_.erase(__p.__i_);}
#endif
     float max_load_factor() const _NOEXCEPT {return __table_.max_load_factor();}
     _LIBCPP_INLINE_VISIBILITY
     void max_load_factor(float __mlf) {__table_.max_load_factor(__mlf);}
     _LIBCPP_INLINE_VISIBILITY
     void rehash(size_type __n) {__table_.__rehash_unique(__n);}
     _LIBCPP_INLINE_VISIBILITY
     void reserve(size_type __n) {__table_.__reserve_unique(__n);}
 
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-
-    _LIBCPP_HIDE_FROM_ABI bool __dereferenceable(const const_iterator* __i) const
-        {return __table_.__dereferenceable(_VSTD::addressof(__i->__i_));}
-    _LIBCPP_HIDE_FROM_ABI bool __decrementable(const const_iterator* __i) const
-        {return __table_.__decrementable(_VSTD::addressof(__i->__i_));}
-    _LIBCPP_HIDE_FROM_ABI bool __addable(const const_iterator* __i, ptrdiff_t __n) const
-        {return __table_.__addable(_VSTD::addressof(__i->__i_), __n);}
-    _LIBCPP_HIDE_FROM_ABI bool __subscriptable(const const_iterator* __i, ptrdiff_t __n) const
-        {return __table_.__addable(_VSTD::addressof(__i->__i_), __n);}
-
-#endif // _LIBCPP_ENABLE_DEBUG_MODE
-
 private:
 
 #ifdef _LIBCPP_CXX03_LANG
     _LIBCPP_HIDE_FROM_ABI __node_holder __construct_node_with_key(const key_type& __k);
 #endif
 };
 
 #if _LIBCPP_STD_VER >= 17
-> unordered_map<remove_const_t<_Key>, _Tp, _Hash,
                    equal_to<remove_const_t<_Key>>, _Allocator>;
 #endif
 
 template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
 unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
         size_type __n, const hasher& __hf, const key_equal& __eql)
     : __table_(__hf, __eql)
 {
-    _VSTD::__debug_db_insert_c(this);
     __table_.__rehash_unique(__n);
 }
 
 template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
 unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
         size_type __n, const hasher& __hf, const key_equal& __eql,
         const allocator_type& __a)
     : __table_(__hf, __eql, typename __table::allocator_type(__a))
 {
-    _VSTD::__debug_db_insert_c(this);
     __table_.__rehash_unique(__n);
 }
 
 template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
 inline
 unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
         const allocator_type& __a)
     : __table_(typename __table::allocator_type(__a))
 {
-    _VSTD::__debug_db_insert_c(this);
 }
 
 template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
 template <class _InputIterator>
 unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
         _InputIterator __first, _InputIterator __last)
 {
-    _VSTD::__debug_db_insert_c(this);
     insert(__first, __last);
 }
 
 template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
 template <class _InputIterator>
 unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
         _InputIterator __first, _InputIterator __last, size_type __n,
         const hasher& __hf, const key_equal& __eql)
     : __table_(__hf, __eql)
 {
-    _VSTD::__debug_db_insert_c(this);
     __table_.__rehash_unique(__n);
     insert(__first, __last);
 }
 
 template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
 template <class _InputIterator>
 unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
         _InputIterator __first, _InputIterator __last, size_type __n,
         const hasher& __hf, const key_equal& __eql, const allocator_type& __a)
     : __table_(__hf, __eql, typename __table::allocator_type(__a))
 {
-    _VSTD::__debug_db_insert_c(this);
     __table_.__rehash_unique(__n);
     insert(__first, __last);
 }
 
 template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
 unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
         const unordered_map& __u)
     : __table_(__u.__table_)
 {
-    _VSTD::__debug_db_insert_c(this);
     __table_.__rehash_unique(__u.bucket_count());
     insert(__u.begin(), __u.end());
 }
 
 template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
 unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
         const unordered_map& __u, const allocator_type& __a)
     : __table_(__u.__table_, typename __table::allocator_type(__a))
 {
-    _VSTD::__debug_db_insert_c(this);
     __table_.__rehash_unique(__u.bucket_count());
     insert(__u.begin(), __u.end());
 }
 
 #ifndef _LIBCPP_CXX03_LANG
 
 template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
 inline
 unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
         unordered_map&& __u)
     _NOEXCEPT_(is_nothrow_move_constructible<__table>::value)
     : __table_(_VSTD::move(__u.__table_))
 {
-    _VSTD::__debug_db_insert_c(this);
-    std::__debug_db_swap(this, std::addressof(__u));
 }
 
 template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
 unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
         unordered_map&& __u, const allocator_type& __a)
     : __table_(_VSTD::move(__u.__table_), typename __table::allocator_type(__a))
 {
-    _VSTD::__debug_db_insert_c(this);
     if (__a != __u.get_allocator())
     {
         iterator __i = __u.begin();
         while (__u.size() != 0) {
             __table_.__emplace_unique(
                 __u.__table_.remove((__i++).__i_)->__value_.__move());
         }
     }
-    else
-        std::__debug_db_swap(this, std::addressof(__u));
 }
 
 template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
 unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
         initializer_list<value_type> __il)
 {
-    _VSTD::__debug_db_insert_c(this);
     insert(__il.begin(), __il.end());
 }
 
 template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
 unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
         initializer_list<value_type> __il, size_type __n, const hasher& __hf,
         const key_equal& __eql)
     : __table_(__hf, __eql)
 {
-    _VSTD::__debug_db_insert_c(this);
     __table_.__rehash_unique(__n);
     insert(__il.begin(), __il.end());
 }
 
 template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
 unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map(
         initializer_list<value_type> __il, size_type __n, const hasher& __hf,
         const key_equal& __eql, const allocator_type& __a)
     : __table_(__hf, __eql, typename __table::allocator_type(__a))
 {
-    _VSTD::__debug_db_insert_c(this);
     __table_.__rehash_unique(__n);
     insert(__il.begin(), __il.end());
 }
 
 template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
 inline
 unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>&
 unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::operator=(unordered_map&& __u)
template <class _Key2, class _Tp2, class _Hash2, class _Pred2, class _Alloc2>
         friend class _LIBCPP_TEMPLATE_VIS unordered_map;
     template <class _Key2, class _Tp2, class _Hash2, class _Pred2, class _Alloc2>
         friend class _LIBCPP_TEMPLATE_VIS unordered_multimap;
 
     _LIBCPP_INLINE_VISIBILITY
     unordered_multimap()
         _NOEXCEPT_(is_nothrow_default_constructible<__table>::value)
     {
-        _VSTD::__debug_db_insert_c(this);
     }
     explicit _LIBCPP_HIDE_FROM_ABI unordered_multimap(size_type __n, const hasher& __hf = hasher(),
                                 const key_equal& __eql = key_equal());
     _LIBCPP_HIDE_FROM_ABI unordered_multimap(size_type __n, const hasher& __hf,
                                 const key_equal& __eql,
                                 const allocator_type& __a);
     template <class _InputIterator>
     _LIBCPP_HIDE_FROM_ABI unordered_multimap(_InputIterator __first, _InputIterator __last);
#endif // _LIBCPP_STD_VER >= 20
     _LIBCPP_INLINE_VISIBILITY
     float max_load_factor() const _NOEXCEPT {return __table_.max_load_factor();}
     _LIBCPP_INLINE_VISIBILITY
     void max_load_factor(float __mlf) {__table_.max_load_factor(__mlf);}
     _LIBCPP_INLINE_VISIBILITY
     void rehash(size_type __n) {__table_.__rehash_multi(__n);}
     _LIBCPP_INLINE_VISIBILITY
     void reserve(size_type __n) {__table_.__reserve_multi(__n);}
-
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-
-    _LIBCPP_HIDE_FROM_ABI bool __dereferenceable(const const_iterator* __i) const
-        {return __table_.__dereferenceable(_VSTD::addressof(__i->__i_));}
-    _LIBCPP_HIDE_FROM_ABI bool __decrementable(const const_iterator* __i) const
-        {return __table_.__decrementable(_VSTD::addressof(__i->__i_));}
-    _LIBCPP_HIDE_FROM_ABI bool __addable(const const_iterator* __i, ptrdiff_t __n) const
-        {return __table_.__addable(_VSTD::addressof(__i->__i_), __n);}
-    _LIBCPP_HIDE_FROM_ABI bool __subscriptable(const const_iterator* __i, ptrdiff_t __n) const
-        {return __table_.__addable(_VSTD::addressof(__i->__i_), __n);}
-
-#endif // _LIBCPP_ENABLE_DEBUG_MODE
-
-
 };
 
 #if _LIBCPP_STD_VER >= 17
 template<class _InputIterator,
          class _Hash = hash<__iter_key_type<_InputIterator>>,
          class _Pred = equal_to<__iter_key_type<_InputIterator>>,
          class _Allocator = allocator<__iter_to_alloc_type<_InputIterator>>,
          class = enable_if_t<__has_input_iterator_category<_InputIterator>::value>,
-> unordered_multimap<remove_const_t<_Key>, _Tp, _Hash,
                         equal_to<remove_const_t<_Key>>, _Allocator>;
 #endif
 
 template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
 unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
         size_type __n, const hasher& __hf, const key_equal& __eql)
     : __table_(__hf, __eql)
 {
-    _VSTD::__debug_db_insert_c(this);
     __table_.__rehash_multi(__n);
 }
 
 template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
 unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
         size_type __n, const hasher& __hf, const key_equal& __eql,
         const allocator_type& __a)
     : __table_(__hf, __eql, typename __table::allocator_type(__a))
 {
-    _VSTD::__debug_db_insert_c(this);
     __table_.__rehash_multi(__n);
 }
 
 template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
 template <class _InputIterator>
 unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
         _InputIterator __first, _InputIterator __last)
 {
-    _VSTD::__debug_db_insert_c(this);
     insert(__first, __last);
 }
 
 template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
 template <class _InputIterator>
 unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
         _InputIterator __first, _InputIterator __last, size_type __n,
         const hasher& __hf, const key_equal& __eql)
     : __table_(__hf, __eql)
 {
-    _VSTD::__debug_db_insert_c(this);
     __table_.__rehash_multi(__n);
     insert(__first, __last);
 }
 
 template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
 template <class _InputIterator>
 unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
         _InputIterator __first, _InputIterator __last, size_type __n,
         const hasher& __hf, const key_equal& __eql, const allocator_type& __a)
     : __table_(__hf, __eql, typename __table::allocator_type(__a))
 {
-    _VSTD::__debug_db_insert_c(this);
     __table_.__rehash_multi(__n);
     insert(__first, __last);
 }
 
 template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
 inline
 unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
         const allocator_type& __a)
     : __table_(typename __table::allocator_type(__a))
 {
-    _VSTD::__debug_db_insert_c(this);
 }
 
 template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
 unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
         const unordered_multimap& __u)
     : __table_(__u.__table_)
 {
-    _VSTD::__debug_db_insert_c(this);
     __table_.__rehash_multi(__u.bucket_count());
     insert(__u.begin(), __u.end());
 }
 
 template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
 unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
         const unordered_multimap& __u, const allocator_type& __a)
     : __table_(__u.__table_, typename __table::allocator_type(__a))
 {
-    _VSTD::__debug_db_insert_c(this);
     __table_.__rehash_multi(__u.bucket_count());
     insert(__u.begin(), __u.end());
 }
 
 #ifndef _LIBCPP_CXX03_LANG
 
 template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
 inline
 unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
         unordered_multimap&& __u)
     _NOEXCEPT_(is_nothrow_move_constructible<__table>::value)
     : __table_(_VSTD::move(__u.__table_))
 {
-    _VSTD::__debug_db_insert_c(this);
-    std::__debug_db_swap(this, std::addressof(__u));
 }
 
 template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
 unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
         unordered_multimap&& __u, const allocator_type& __a)
     : __table_(_VSTD::move(__u.__table_), typename __table::allocator_type(__a))
 {
-    _VSTD::__debug_db_insert_c(this);
     if (__a != __u.get_allocator())
     {
         iterator __i = __u.begin();
         while (__u.size() != 0)
         {
             __table_.__insert_multi(
                 __u.__table_.remove((__i++).__i_)->__value_.__move());
         }
     }
-    else
-        std::__debug_db_swap(this, std::addressof(__u));
 }
 
 template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
 unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
         initializer_list<value_type> __il)
 {
-    _VSTD::__debug_db_insert_c(this);
     insert(__il.begin(), __il.end());
 }
 
 template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
 unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
         initializer_list<value_type> __il, size_type __n, const hasher& __hf,
         const key_equal& __eql)
     : __table_(__hf, __eql)
 {
-    _VSTD::__debug_db_insert_c(this);
     __table_.__rehash_multi(__n);
     insert(__il.begin(), __il.end());
 }
 
 template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
 unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_multimap(
         initializer_list<value_type> __il, size_type __n, const hasher& __hf,
         const key_equal& __eql, const allocator_type& __a)
     : __table_(__hf, __eql, typename __table::allocator_type(__a))
 {
-    _VSTD::__debug_db_insert_c(this);
     __table_.__rehash_multi(__n);
     insert(__il.begin(), __il.end());
 }
 
 template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
 inline
 unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>&
 unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::operator=(unordered_multimap&& __u)

libcxx/include/unordered_set

 }  // std
 
 */
 
 #include <__algorithm/is_permutation.h>
 #include <__assert> // all public C++ headers provide the assertion handler
 #include <__availability>
 #include <__config>
-#include <__debug>
 #include <__functional/is_transparent.h>
 #include <__functional/operations.h>
 #include <__hash_table>
 #include <__iterator/distance.h>
 #include <__iterator/erase_if_container.h>
 #include <__iterator/iterator_traits.h>
 #include <__memory/addressof.h>
 #include <__memory/allocator.h>
template <class _Value2, class _Hash2, class _Pred2, class _Alloc2>
         friend class _LIBCPP_TEMPLATE_VIS unordered_set;
     template <class _Value2, class _Hash2, class _Pred2, class _Alloc2>
         friend class _LIBCPP_TEMPLATE_VIS unordered_multiset;
 
     _LIBCPP_INLINE_VISIBILITY
     unordered_set()
         _NOEXCEPT_(is_nothrow_default_constructible<__table>::value)
     {
-        _VSTD::__debug_db_insert_c(this);
     }
     explicit _LIBCPP_HIDE_FROM_ABI unordered_set(size_type __n, const hasher& __hf = hasher(),
                            const key_equal& __eql = key_equal());
 #if _LIBCPP_STD_VER >= 14
     inline _LIBCPP_INLINE_VISIBILITY
     unordered_set(size_type __n, const allocator_type& __a)
         : unordered_set(__n, hasher(), key_equal(), __a) {}
     inline _LIBCPP_INLINE_VISIBILITY

 
 #ifndef _LIBCPP_CXX03_LANG
     template <class... _Args>
         _LIBCPP_INLINE_VISIBILITY
         pair<iterator, bool> emplace(_Args&&... __args)
             {return __table_.__emplace_unique(_VSTD::forward<_Args>(__args)...);}
     template <class... _Args>
     _LIBCPP_INLINE_VISIBILITY
-    iterator emplace_hint(const_iterator __p, _Args&&... __args) {
-        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(std::addressof(__p)) == this,
-            "unordered_set::emplace_hint(const_iterator, args...) called with an iterator not"
-            " referring to this unordered_set");
-        (void)__p;
+    iterator emplace_hint(const_iterator, _Args&&... __args) {
         return __table_.__emplace_unique(std::forward<_Args>(__args)...).first;
     }
 
     _LIBCPP_INLINE_VISIBILITY
     pair<iterator, bool> insert(value_type&& __x)
         {return __table_.__insert_unique(_VSTD::move(__x));}
     _LIBCPP_INLINE_VISIBILITY
-    iterator insert(const_iterator __p, value_type&& __x) {
-        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(std::addressof(__p)) == this,
-            "unordered_set::insert(const_iterator, value_type&&) called with an iterator not"
-            " referring to this unordered_set");
-        (void)__p;
+    iterator insert(const_iterator, value_type&& __x) {
         return insert(std::move(__x)).first;
     }
 
     _LIBCPP_INLINE_VISIBILITY
     void insert(initializer_list<value_type> __il)
         {insert(__il.begin(), __il.end());}
 #endif // _LIBCPP_CXX03_LANG
     _LIBCPP_INLINE_VISIBILITY
     pair<iterator, bool> insert(const value_type& __x)
         {return __table_.__insert_unique(__x);}
 
     _LIBCPP_INLINE_VISIBILITY
-    iterator insert(const_iterator __p, const value_type& __x) {
-        _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(std::addressof(__p)) == this,
-            "unordered_set::insert(const_iterator, const value_type&) called with an iterator not"
-            " referring to this unordered_set");
-        (void)__p;
+    iterator insert(const_iterator, const value_type& __x) {
         return insert(__x).first;
     }
     template <class _InputIterator>
         _LIBCPP_INLINE_VISIBILITY
         void insert(_InputIterator __first, _InputIterator __last);
 
     _LIBCPP_INLINE_VISIBILITY
     iterator erase(const_iterator __p) {return __table_.erase(__p);}
#endif // _LIBCPP_STD_VER >= 20
     _LIBCPP_INLINE_VISIBILITY
     float max_load_factor() const _NOEXCEPT {return __table_.max_load_factor();}
     _LIBCPP_INLINE_VISIBILITY
     void max_load_factor(float __mlf) {__table_.max_load_factor(__mlf);}
     _LIBCPP_INLINE_VISIBILITY
     void rehash(size_type __n) {__table_.__rehash_unique(__n);}
     _LIBCPP_INLINE_VISIBILITY
     void reserve(size_type __n) {__table_.__reserve_unique(__n);}
-
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-
-    _LIBCPP_HIDE_FROM_ABI bool __dereferenceable(const const_iterator* __i) const
-        {return __table_.__dereferenceable(__i);}
-    _LIBCPP_HIDE_FROM_ABI bool __decrementable(const const_iterator* __i) const
-        {return __table_.__decrementable(__i);}
-    _LIBCPP_HIDE_FROM_ABI bool __addable(const const_iterator* __i, ptrdiff_t __n) const
-        {return __table_.__addable(__i, __n);}
-    _LIBCPP_HIDE_FROM_ABI bool __subscriptable(const const_iterator* __i, ptrdiff_t __n) const
-        {return __table_.__addable(__i, __n);}
-
-#endif // _LIBCPP_ENABLE_DEBUG_MODE
-
 };
 
 #if _LIBCPP_STD_VER >= 17
 template<class _InputIterator,
          class _Hash = hash<__iter_value_type<_InputIterator>>,
          class _Pred = equal_to<__iter_value_type<_InputIterator>>,
          class _Allocator = allocator<__iter_value_type<_InputIterator>>,
          class = enable_if_t<__has_input_iterator_category<_InputIterator>::value>,
unordered_set(initializer_list<_Tp>, typename allocator_traits<_Allocator>::size_type, _Hash, _Allocator)
   -> unordered_set<_Tp, _Hash, equal_to<_Tp>, _Allocator>;
 #endif
 
 template <class _Value, class _Hash, class _Pred, class _Alloc>
 unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(size_type __n,
         const hasher& __hf, const key_equal& __eql)
     : __table_(__hf, __eql)
 {
-    _VSTD::__debug_db_insert_c(this);
     __table_.__rehash_unique(__n);
 }
 
 template <class _Value, class _Hash, class _Pred, class _Alloc>
 unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(size_type __n,
         const hasher& __hf, const key_equal& __eql, const allocator_type& __a)
     : __table_(__hf, __eql, __a)
 {
-    _VSTD::__debug_db_insert_c(this);
     __table_.__rehash_unique(__n);
 }
 
 template <class _Value, class _Hash, class _Pred, class _Alloc>
 template <class _InputIterator>
 unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
         _InputIterator __first, _InputIterator __last)
 {
-    _VSTD::__debug_db_insert_c(this);
     insert(__first, __last);
 }
 
 template <class _Value, class _Hash, class _Pred, class _Alloc>
 template <class _InputIterator>
 unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
         _InputIterator __first, _InputIterator __last, size_type __n,
         const hasher& __hf, const key_equal& __eql)
     : __table_(__hf, __eql)
 {
-    _VSTD::__debug_db_insert_c(this);
     __table_.__rehash_unique(__n);
     insert(__first, __last);
 }
 
 template <class _Value, class _Hash, class _Pred, class _Alloc>
 template <class _InputIterator>
 unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
         _InputIterator __first, _InputIterator __last, size_type __n,
         const hasher& __hf, const key_equal& __eql, const allocator_type& __a)
     : __table_(__hf, __eql, __a)
 {
-    _VSTD::__debug_db_insert_c(this);
     __table_.__rehash_unique(__n);
     insert(__first, __last);
 }
 
 template <class _Value, class _Hash, class _Pred, class _Alloc>
 inline
 unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
         const allocator_type& __a)
     : __table_(__a)
 {
-    _VSTD::__debug_db_insert_c(this);
 }
 
 template <class _Value, class _Hash, class _Pred, class _Alloc>
 unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
         const unordered_set& __u)
     : __table_(__u.__table_)
 {
-    _VSTD::__debug_db_insert_c(this);
     __table_.__rehash_unique(__u.bucket_count());
     insert(__u.begin(), __u.end());
 }
 
 template <class _Value, class _Hash, class _Pred, class _Alloc>
 unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
         const unordered_set& __u, const allocator_type& __a)
     : __table_(__u.__table_, __a)
 {
-    _VSTD::__debug_db_insert_c(this);
     __table_.__rehash_unique(__u.bucket_count());
     insert(__u.begin(), __u.end());
 }
 
 #ifndef _LIBCPP_CXX03_LANG
 
 template <class _Value, class _Hash, class _Pred, class _Alloc>
 inline
 unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
         unordered_set&& __u)
     _NOEXCEPT_(is_nothrow_move_constructible<__table>::value)
     : __table_(_VSTD::move(__u.__table_))
 {
-    _VSTD::__debug_db_insert_c(this);
-    std::__debug_db_swap(this, std::addressof(__u));
 }
 
 template <class _Value, class _Hash, class _Pred, class _Alloc>
 unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
         unordered_set&& __u, const allocator_type& __a)
     : __table_(_VSTD::move(__u.__table_), __a)
 {
-    _VSTD::__debug_db_insert_c(this);
     if (__a != __u.get_allocator())
     {
         iterator __i = __u.begin();
         while (__u.size() != 0)
             __table_.__insert_unique(_VSTD::move(__u.__table_.remove(__i++)->__value_));
     }
-    else
-        std::__debug_db_swap(this, std::addressof(__u));
 }
 
 template <class _Value, class _Hash, class _Pred, class _Alloc>
 unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
         initializer_list<value_type> __il)
 {
-    _VSTD::__debug_db_insert_c(this);
     insert(__il.begin(), __il.end());
 }
 
 template <class _Value, class _Hash, class _Pred, class _Alloc>
 unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
         initializer_list<value_type> __il, size_type __n, const hasher& __hf,
         const key_equal& __eql)
     : __table_(__hf, __eql)
 {
-    _VSTD::__debug_db_insert_c(this);
     __table_.__rehash_unique(__n);
     insert(__il.begin(), __il.end());
 }
 
 template <class _Value, class _Hash, class _Pred, class _Alloc>
 unordered_set<_Value, _Hash, _Pred, _Alloc>::unordered_set(
         initializer_list<value_type> __il, size_type __n, const hasher& __hf,
         const key_equal& __eql, const allocator_type& __a)
     : __table_(__hf, __eql, __a)
 {
-    _VSTD::__debug_db_insert_c(this);
     __table_.__rehash_unique(__n);
     insert(__il.begin(), __il.end());
 }
 
 template <class _Value, class _Hash, class _Pred, class _Alloc>
 inline
 unordered_set<_Value, _Hash, _Pred, _Alloc>&
 unordered_set<_Value, _Hash, _Pred, _Alloc>::operator=(unordered_set&& __u)
template <class _Value2, class _Hash2, class _Pred2, class _Alloc2>
         friend class _LIBCPP_TEMPLATE_VIS unordered_set;
     template <class _Value2, class _Hash2, class _Pred2, class _Alloc2>
         friend class _LIBCPP_TEMPLATE_VIS unordered_multiset;
 
     _LIBCPP_INLINE_VISIBILITY
     unordered_multiset()
         _NOEXCEPT_(is_nothrow_default_constructible<__table>::value)
     {
-        _VSTD::__debug_db_insert_c(this);
     }
     explicit _LIBCPP_HIDE_FROM_ABI unordered_multiset(size_type __n, const hasher& __hf = hasher(),
                                 const key_equal& __eql = key_equal());
     _LIBCPP_HIDE_FROM_ABI unordered_multiset(size_type __n, const hasher& __hf,
                        const key_equal& __eql, const allocator_type& __a);
 #if _LIBCPP_STD_VER >= 14
     inline _LIBCPP_INLINE_VISIBILITY
     unordered_multiset(size_type __n, const allocator_type& __a)
#endif // _LIBCPP_STD_VER >= 20
     _LIBCPP_INLINE_VISIBILITY
     float max_load_factor() const _NOEXCEPT {return __table_.max_load_factor();}
     _LIBCPP_INLINE_VISIBILITY
     void max_load_factor(float __mlf) {__table_.max_load_factor(__mlf);}
     _LIBCPP_INLINE_VISIBILITY
     void rehash(size_type __n) {__table_.__rehash_multi(__n);}
     _LIBCPP_INLINE_VISIBILITY
     void reserve(size_type __n) {__table_.__reserve_multi(__n);}
-
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-
-    _LIBCPP_HIDE_FROM_ABI bool __dereferenceable(const const_iterator* __i) const
-        {return __table_.__dereferenceable(__i);}
-    _LIBCPP_HIDE_FROM_ABI bool __decrementable(const const_iterator* __i) const
-        {return __table_.__decrementable(__i);}
-    _LIBCPP_HIDE_FROM_ABI bool __addable(const const_iterator* __i, ptrdiff_t __n) const
-        {return __table_.__addable(__i, __n);}
-    _LIBCPP_HIDE_FROM_ABI bool __subscriptable(const const_iterator* __i, ptrdiff_t __n) const
-        {return __table_.__addable(__i, __n);}
-
-#endif // _LIBCPP_ENABLE_DEBUG_MODE
-
 };
 
 #if _LIBCPP_STD_VER >= 17
 template<class _InputIterator,
          class _Hash = hash<__iter_value_type<_InputIterator>>,
          class _Pred = equal_to<__iter_value_type<_InputIterator>>,
          class _Allocator = allocator<__iter_value_type<_InputIterator>>,
          class = enable_if_t<__has_input_iterator_category<_InputIterator>::value>,
unordered_multiset(initializer_list<_Tp>, typename allocator_traits<_Allocator>::size_type, _Hash, _Allocator)
   -> unordered_multiset<_Tp, _Hash, equal_to<_Tp>, _Allocator>;
 #endif
 
 template <class _Value, class _Hash, class _Pred, class _Alloc>
 unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
         size_type __n, const hasher& __hf, const key_equal& __eql)
     : __table_(__hf, __eql)
 {
-    _VSTD::__debug_db_insert_c(this);
     __table_.__rehash_multi(__n);
 }
 
 template <class _Value, class _Hash, class _Pred, class _Alloc>
 unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
         size_type __n, const hasher& __hf, const key_equal& __eql,
         const allocator_type& __a)
     : __table_(__hf, __eql, __a)
 {
-    _VSTD::__debug_db_insert_c(this);
     __table_.__rehash_multi(__n);
 }
 
 template <class _Value, class _Hash, class _Pred, class _Alloc>
 template <class _InputIterator>
 unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
         _InputIterator __first, _InputIterator __last)
 {
-    _VSTD::__debug_db_insert_c(this);
     insert(__first, __last);
 }
 
 template <class _Value, class _Hash, class _Pred, class _Alloc>
 template <class _InputIterator>
 unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
         _InputIterator __first, _InputIterator __last, size_type __n,
         const hasher& __hf, const key_equal& __eql)
     : __table_(__hf, __eql)
 {
-    _VSTD::__debug_db_insert_c(this);
     __table_.__rehash_multi(__n);
     insert(__first, __last);
 }
 
 template <class _Value, class _Hash, class _Pred, class _Alloc>
 template <class _InputIterator>
 unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
         _InputIterator __first, _InputIterator __last, size_type __n,
         const hasher& __hf, const key_equal& __eql, const allocator_type& __a)
     : __table_(__hf, __eql, __a)
 {
-    _VSTD::__debug_db_insert_c(this);
     __table_.__rehash_multi(__n);
     insert(__first, __last);
 }
 
 template <class _Value, class _Hash, class _Pred, class _Alloc>
 inline
 unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
         const allocator_type& __a)
     : __table_(__a)
 {
-    _VSTD::__debug_db_insert_c(this);
 }
 
 template <class _Value, class _Hash, class _Pred, class _Alloc>
 unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
         const unordered_multiset& __u)
     : __table_(__u.__table_)
 {
-    _VSTD::__debug_db_insert_c(this);
     __table_.__rehash_multi(__u.bucket_count());
     insert(__u.begin(), __u.end());
 }
 
 template <class _Value, class _Hash, class _Pred, class _Alloc>
 unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
         const unordered_multiset& __u, const allocator_type& __a)
     : __table_(__u.__table_, __a)
 {
-    _VSTD::__debug_db_insert_c(this);
     __table_.__rehash_multi(__u.bucket_count());
     insert(__u.begin(), __u.end());
 }
 
 #ifndef _LIBCPP_CXX03_LANG
 
 template <class _Value, class _Hash, class _Pred, class _Alloc>
 inline
 unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
         unordered_multiset&& __u)
     _NOEXCEPT_(is_nothrow_move_constructible<__table>::value)
     : __table_(_VSTD::move(__u.__table_))
 {
-    _VSTD::__debug_db_insert_c(this);
-    std::__debug_db_swap(this, std::addressof(__u));
 }
 
 template <class _Value, class _Hash, class _Pred, class _Alloc>
 unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
         unordered_multiset&& __u, const allocator_type& __a)
     : __table_(_VSTD::move(__u.__table_), __a)
 {
-    _VSTD::__debug_db_insert_c(this);
     if (__a != __u.get_allocator())
     {
         iterator __i = __u.begin();
         while (__u.size() != 0)
             __table_.__insert_multi(_VSTD::move(__u.__table_.remove(__i++)->__value_));
     }
-    else
-        std::__debug_db_swap(this, std::addressof(__u));
 }
 
 template <class _Value, class _Hash, class _Pred, class _Alloc>
 unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
         initializer_list<value_type> __il)
 {
-    _VSTD::__debug_db_insert_c(this);
     insert(__il.begin(), __il.end());
 }
 
 template <class _Value, class _Hash, class _Pred, class _Alloc>
 unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
         initializer_list<value_type> __il, size_type __n, const hasher& __hf,
         const key_equal& __eql)
     : __table_(__hf, __eql)
 {
-    _VSTD::__debug_db_insert_c(this);
     __table_.__rehash_multi(__n);
     insert(__il.begin(), __il.end());
 }
 
 template <class _Value, class _Hash, class _Pred, class _Alloc>
 unordered_multiset<_Value, _Hash, _Pred, _Alloc>::unordered_multiset(
         initializer_list<value_type> __il, size_type __n, const hasher& __hf,
         const key_equal& __eql, const allocator_type& __a)
     : __table_(__hf, __eql, __a)
 {
-    _VSTD::__debug_db_insert_c(this);
     __table_.__rehash_multi(__n);
     insert(__il.begin(), __il.end());
 }
 
 template <class _Value, class _Hash, class _Pred, class _Alloc>
 inline
 unordered_multiset<_Value, _Hash, _Pred, _Alloc>&
 unordered_multiset<_Value, _Hash, _Pred, _Alloc>::operator=(

libcxx/include/vector

 #include <__algorithm/remove_if.h>
 #include <__algorithm/rotate.h>
 #include <__algorithm/unwrap_iter.h>
 #include <__assert> // all public C++ headers provide the assertion handler
 #include <__availability>
 #include <__bit_reference>
 #include <__concepts/same_as.h>
 #include <__config>
-#include <__debug>
 #include <__format/enable_insertable.h>
 #include <__format/formatter.h>
 #include <__format/formatter_bool.h>
 #include <__functional/hash.h>
 #include <__functional/unary_function.h>
 #include <__iterator/advance.h>
 #include <__iterator/distance.h>
 #include <__iterator/iterator_traits.h>
public:
 
     static_assert(is_same<allocator_type, __rebind_alloc<__alloc_traits, value_type> >::value,
                   "[allocator.requirements] states that rebinding an allocator to the same type should result in the "
                   "original allocator");
 
     _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
     vector() _NOEXCEPT_(is_nothrow_default_constructible<allocator_type>::value)
     {
-        std::__debug_db_insert_c(this);
     }
     _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI explicit vector(const allocator_type& __a)
 #if _LIBCPP_STD_VER <= 14
         _NOEXCEPT_(is_nothrow_copy_constructible<allocator_type>::value)
 #else
         _NOEXCEPT
 #endif
         : __end_cap_(nullptr, __a)
     {
-        std::__debug_db_insert_c(this);
     }
     _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI explicit vector(size_type __n);
 #if _LIBCPP_STD_VER >= 14
     _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI explicit vector(size_type __n, const allocator_type& __a);
 #endif
     _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI vector(size_type __n, const value_type& __x);
 
     template <class = __enable_if_t<__is_allocator<_Allocator>::value> >
     _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
     vector(size_type __n, const value_type& __x, const allocator_type& __a)
         : __end_cap_(nullptr, __a)
     {
-      std::__debug_db_insert_c(this);
       if (__n > 0)
       {
           __vallocate(__n);
           __construct_at_end(__n, __x);
       }
     }
 
   template <class _InputIterator,

 #endif
 
 private:
   class __destroy_vector {
     public:
       _LIBCPP_CONSTEXPR _LIBCPP_HIDE_FROM_ABI __destroy_vector(vector& __vec) : __vec_(__vec) {}
 
       _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void operator()() {
-          std::__debug_db_erase_c(std::addressof(__vec_));
-
           if (__vec_.__begin_ != nullptr) {
             __vec_.__clear();
             __vec_.__annotate_delete();
             __alloc_traits::deallocate(__vec_.__alloc(), __vec_.__begin_, __vec_.capacity());
           }
       }
 
     private:
#endif
     _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI iterator erase(const_iterator __first, const_iterator __last);
 
     _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
     void clear() _NOEXCEPT
     {
         size_type __old_size = size();
         __clear();
         __annotate_shrink(__old_size);
-        std::__debug_db_invalidate_all(this);
     }
 
     _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void resize(size_type __sz);
     _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void resize(size_type __sz, const_reference __x);
 
     _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void swap(vector&)
 #if _LIBCPP_STD_VER >= 14
         _NOEXCEPT;
 #else
         _NOEXCEPT_(!__alloc_traits::propagate_on_container_swap::value ||
                     __is_nothrow_swappable<allocator_type>::value);
 #endif
 
     _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI bool __invariants() const;
 
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-
-    bool __dereferenceable(const const_iterator* __i) const;
-    bool __decrementable(const const_iterator* __i) const;
-    bool __addable(const const_iterator* __i, ptrdiff_t __n) const;
-    bool __subscriptable(const const_iterator* __i, ptrdiff_t __n) const;
-
-#endif // _LIBCPP_ENABLE_DEBUG_MODE
-
 private:
     pointer __begin_ = nullptr;
     pointer __end_ = nullptr;
     __compressed_pair<pointer, allocator_type> __end_cap_ =
         __compressed_pair<pointer, allocator_type>(nullptr, __default_init_tag());
 
-    _LIBCPP_HIDE_FROM_ABI void __invalidate_iterators_past(pointer __new_last);
-
     //  Allocate space for __n objects
     //  throws length_error if __n > max_size()
     //  throws (probably bad_alloc) if memory run out
     //  Precondition:  __begin_ == __end_ == __end_cap() == 0
     //  Precondition:  __n > 0
     //  Postcondition:  capacity() >= __n
     //  Postcondition:  size() == 0
     _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __vallocate(size_type __n) {
private:
     _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __construct_at_end(size_type __n);
     _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
     void __construct_at_end(size_type __n, const_reference __x);
 
     template <class _InputIterator, class _Sentinel>
     _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
     void __init_with_size(_InputIterator __first, _Sentinel __last, size_type __n) {
       auto __guard = std::__make_exception_guard(__destroy_vector(*this));
-      std::__debug_db_insert_c(this);
 
       if (__n > 0) {
         __vallocate(__n);
         __construct_at_end(__first, __last, __n);
       }
 
       __guard.__complete();
     }
 
     template <class _InputIterator, class _Sentinel>
     _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
     void __init_with_sentinel(_InputIterator __first, _Sentinel __last) {
       auto __guard = std::__make_exception_guard(__destroy_vector(*this));
-      std::__debug_db_insert_c(this);
 
       for (; __first != __last; ++__first)
         emplace_back(*__first);
 
       __guard.__complete();
     }
 
     template <class _Iterator, class _Sentinel>
private:
 
     template <class _InputIterator, class _Sentinel>
     _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
     void __construct_at_end(_InputIterator __first, _Sentinel __last, size_type __n);
 
     _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __append(size_type __n);
     _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __append(size_type __n, const_reference __x);
     _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
-    iterator       __make_iter(pointer __p) _NOEXCEPT { return iterator(this, __p); }
+    iterator       __make_iter(pointer __p) _NOEXCEPT { return iterator(__p); }
     _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
-    const_iterator __make_iter(const_pointer __p) const _NOEXCEPT { return const_iterator(this, __p); }
+    const_iterator __make_iter(const_pointer __p) const _NOEXCEPT { return const_iterator(__p); }
     _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __swap_out_circular_buffer(__split_buffer<value_type, allocator_type&>& __v);
     _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI pointer __swap_out_circular_buffer(__split_buffer<value_type, allocator_type&>& __v, pointer __p);
     _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __move_range(pointer __from_s, pointer __from_e, pointer __to);
     _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __move_assign(vector& __c, true_type)
         _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value);
     _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __move_assign(vector& __c, false_type)
         _NOEXCEPT_(__alloc_traits::is_always_equal::value);
     _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
     void __destruct_at_end(pointer __new_last) _NOEXCEPT
     {
-        if (!__libcpp_is_constant_evaluated())
-            __invalidate_iterators_past(__new_last);
         size_type __old_size = size();
         __base_destruct_at_end(__new_last);
         __annotate_shrink(__old_size);
     }
 
     template <class _Up>
     _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
     inline void __push_back_slow_path(_Up&& __x);
vector<_Tp, _Allocator>::__swap_out_circular_buffer(__split_buffer<value_type, allocator_type&>& __v)
     __v.__begin_   = std::__uninitialized_allocator_move_if_noexcept(
                        __alloc(), _RevIter(__end_), _RevIter(__begin_), _RevIter(__v.__begin_))
                        .base();
     std::swap(this->__begin_, __v.__begin_);
     std::swap(this->__end_, __v.__end_);
     std::swap(this->__end_cap(), __v.__end_cap());
     __v.__first_ = __v.__begin_;
     __annotate_new(size());
-    std::__debug_db_invalidate_all(this);
 }
 
 template <class _Tp, class _Allocator>
 _LIBCPP_CONSTEXPR_SINCE_CXX20
 typename vector<_Tp, _Allocator>::pointer
 vector<_Tp, _Allocator>::__swap_out_circular_buffer(__split_buffer<value_type, allocator_type&>& __v, pointer __p)
 {
     __annotate_delete();
     pointer __r = __v.__begin_;
     using _RevIter = std::reverse_iterator<pointer>;
     __v.__begin_   = std::__uninitialized_allocator_move_if_noexcept(
                        __alloc(), _RevIter(__p), _RevIter(__begin_), _RevIter(__v.__begin_))
                        .base();
     __v.__end_ = std::__uninitialized_allocator_move_if_noexcept(__alloc(), __p, __end_, __v.__end_);
     std::swap(this->__begin_, __v.__begin_);
     std::swap(this->__end_, __v.__end_);
     std::swap(this->__end_cap(), __v.__end_cap());
     __v.__first_ = __v.__begin_;
     __annotate_new(size());
-    std::__debug_db_invalidate_all(this);
     return __r;
 }
 
 template <class _Tp, class _Allocator>
 _LIBCPP_CONSTEXPR_SINCE_CXX20
 void
 vector<_Tp, _Allocator>::__vdeallocate() _NOEXCEPT
 {
vector<_Tp, _Allocator>::__append(size_type __n, const_reference __x)
     }
 }
 
 template <class _Tp, class _Allocator>
 _LIBCPP_CONSTEXPR_SINCE_CXX20
 vector<_Tp, _Allocator>::vector(size_type __n)
 {
     auto __guard = std::__make_exception_guard(__destroy_vector(*this));
-    std::__debug_db_insert_c(this);
     if (__n > 0)
     {
         __vallocate(__n);
         __construct_at_end(__n);
     }
     __guard.__complete();
 }
 
 #if _LIBCPP_STD_VER >= 14
 template <class _Tp, class _Allocator>
 _LIBCPP_CONSTEXPR_SINCE_CXX20
 vector<_Tp, _Allocator>::vector(size_type __n, const allocator_type& __a)
     : __end_cap_(nullptr, __a)
 {
     auto __guard = std::__make_exception_guard(__destroy_vector(*this));
-    std::__debug_db_insert_c(this);
     if (__n > 0)
     {
         __vallocate(__n);
         __construct_at_end(__n);
     }
     __guard.__complete();
 }
 #endif
 
 template <class _Tp, class _Allocator>
 _LIBCPP_CONSTEXPR_SINCE_CXX20
 vector<_Tp, _Allocator>::vector(size_type __n, const value_type& __x)
 {
     auto __guard = std::__make_exception_guard(__destroy_vector(*this));
-    std::__debug_db_insert_c(this);
     if (__n > 0)
     {
         __vallocate(__n);
         __construct_at_end(__n, __x);
     }
     __guard.__complete();
 }
 

 vector<_Tp, _Allocator>::vector(vector&& __x)
 #if _LIBCPP_STD_VER >= 17
         noexcept
 #else
         _NOEXCEPT_(is_nothrow_move_constructible<allocator_type>::value)
 #endif
     : __end_cap_(nullptr, std::move(__x.__alloc()))
 {
-    std::__debug_db_insert_c(this);
-    std::__debug_db_swap(this, std::addressof(__x));
     this->__begin_ = __x.__begin_;
     this->__end_ = __x.__end_;
     this->__end_cap() = __x.__end_cap();
     __x.__begin_ = __x.__end_ = __x.__end_cap() = nullptr;
 }
 
 template <class _Tp, class _Allocator>
 _LIBCPP_CONSTEXPR_SINCE_CXX20
 inline _LIBCPP_HIDE_FROM_ABI
 vector<_Tp, _Allocator>::vector(vector&& __x, const __type_identity_t<allocator_type>& __a)
     : __end_cap_(nullptr, __a)
 {
-    std::__debug_db_insert_c(this);
     if (__a == __x.__alloc())
     {
         this->__begin_ = __x.__begin_;
         this->__end_ = __x.__end_;
         this->__end_cap() = __x.__end_cap();
         __x.__begin_ = __x.__end_ = __x.__end_cap() = nullptr;
-        std::__debug_db_swap(this, std::addressof(__x));
     }
     else
     {
         typedef move_iterator<iterator> _Ip;
         auto __guard = std::__make_exception_guard(__destroy_vector(*this));
         assign(_Ip(__x.begin()), _Ip(__x.end()));
         __guard.__complete();
     }
 }
 
 #ifndef _LIBCPP_CXX03_LANG
 
 template <class _Tp, class _Allocator>
 _LIBCPP_CONSTEXPR_SINCE_CXX20
 inline _LIBCPP_HIDE_FROM_ABI
 vector<_Tp, _Allocator>::vector(initializer_list<value_type> __il)
 {
     auto __guard = std::__make_exception_guard(__destroy_vector(*this));
-    std::__debug_db_insert_c(this);
     if (__il.size() > 0)
     {
         __vallocate(__il.size());
         __construct_at_end(__il.begin(), __il.end(), __il.size());
     }
     __guard.__complete();
 }
 
 template <class _Tp, class _Allocator>
 _LIBCPP_CONSTEXPR_SINCE_CXX20
 inline _LIBCPP_HIDE_FROM_ABI
 vector<_Tp, _Allocator>::vector(initializer_list<value_type> __il, const allocator_type& __a)
     : __end_cap_(nullptr, __a)
 {
     auto __guard = std::__make_exception_guard(__destroy_vector(*this));
-    std::__debug_db_insert_c(this);
     if (__il.size() > 0)
     {
         __vallocate(__il.size());
         __construct_at_end(__il.begin(), __il.end(), __il.size());
     }
     __guard.__complete();
 }
 
vector<_Tp, _Allocator>::__move_assign(vector& __c, true_type)
     _NOEXCEPT_(is_nothrow_move_assignable<allocator_type>::value)
 {
     __vdeallocate();
     __move_assign_alloc(__c); // this can throw
     this->__begin_ = __c.__begin_;
     this->__end_ = __c.__end_;
     this->__end_cap() = __c.__end_cap();
     __c.__begin_ = __c.__end_ = __c.__end_cap() = nullptr;
-    std::__debug_db_swap(this, std::addressof(__c));
 }
 
 template <class _Tp, class _Allocator>
 _LIBCPP_CONSTEXPR_SINCE_CXX20
 inline _LIBCPP_HIDE_FROM_ABI
 vector<_Tp, _Allocator>&
 vector<_Tp, _Allocator>::operator=(const vector& __x)
 {
if (__new_size <= capacity())
         }
     }
     else
     {
         __vdeallocate();
         __vallocate(__recommend(__new_size));
         __construct_at_end(__first, __last, __new_size);
     }
-    std::__debug_db_invalidate_all(this);
 }
 
 template <class _Tp, class _Allocator>
 _LIBCPP_CONSTEXPR_SINCE_CXX20
 void
 vector<_Tp, _Allocator>::assign(size_type __n, const_reference __u)
 {
     if (__n <= capacity())
     {
         size_type __s = size();
         std::fill_n(this->__begin_, std::min(__n, __s), __u);
         if (__n > __s)
             __construct_at_end(__n - __s, __u);
         else
             this->__destruct_at_end(this->__begin_ + __n);
     }
     else
     {
         __vdeallocate();
         __vallocate(__recommend(static_cast<size_type>(__n)));
         __construct_at_end(__n, __u);
     }
-    std::__debug_db_invalidate_all(this);
 }
 
 template <class _Tp, class _Allocator>
 _LIBCPP_CONSTEXPR_SINCE_CXX20
 inline _LIBCPP_HIDE_FROM_ABI
 typename vector<_Tp, _Allocator>::iterator
 vector<_Tp, _Allocator>::begin() _NOEXCEPT
 {

 }
 
 template <class _Tp, class _Allocator>
 _LIBCPP_CONSTEXPR_SINCE_CXX20
 inline _LIBCPP_HIDE_FROM_ABI
 typename vector<_Tp, _Allocator>::iterator
 vector<_Tp, _Allocator>::erase(const_iterator __position)
 {
-    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(std::addressof(__position)) == this,
-                         "vector::erase(iterator) called with an iterator not referring to this vector");
     _LIBCPP_ASSERT(__position != end(),
         "vector::erase(iterator) called with a non-dereferenceable iterator");
     difference_type __ps = __position - cbegin();
     pointer __p = this->__begin_ + __ps;
     this->__destruct_at_end(std::move(__p + 1, this->__end_, __p));
-    if (!__libcpp_is_constant_evaluated())
-        this->__invalidate_iterators_past(__p - 1);
     return __make_iter(__p);
 }
 
 template <class _Tp, class _Allocator>
 _LIBCPP_CONSTEXPR_SINCE_CXX20
 typename vector<_Tp, _Allocator>::iterator
 vector<_Tp, _Allocator>::erase(const_iterator __first, const_iterator __last)
 {
-    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(std::addressof(__first)) == this,
-                         "vector::erase(iterator, iterator) called with an iterator not referring to this vector");
-    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(std::addressof(__last)) == this,
-                         "vector::erase(iterator, iterator) called with an iterator not referring to this vector");
-
     _LIBCPP_ASSERT(__first <= __last, "vector::erase(first, last) called with invalid range");
     pointer __p = this->__begin_ + (__first - begin());
     if (__first != __last) {
         this->__destruct_at_end(std::move(__p + (__last - __first), this->__end_, __p));
-        if (!__libcpp_is_constant_evaluated())
-            this->__invalidate_iterators_past(__p - 1);
     }
     return __make_iter(__p);
 }
 
 template <class _Tp, class _Allocator>
 _LIBCPP_CONSTEXPR_SINCE_CXX20
 void
 vector<_Tp, _Allocator>::__move_range(pointer __from_s, pointer __from_e, pointer __to)
vector<_Tp, _Allocator>::__move_range(pointer __from_s, pointer __from_e, pointer __to)
     std::move_backward(__from_s, __from_s + __n, __old_last);
 }
 
 template <class _Tp, class _Allocator>
 _LIBCPP_CONSTEXPR_SINCE_CXX20
 typename vector<_Tp, _Allocator>::iterator
 vector<_Tp, _Allocator>::insert(const_iterator __position, const_reference __x)
 {
-    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(std::addressof(__position)) == this,
-                         "vector::insert(iterator, x) called with an iterator not referring to this vector");
     pointer __p = this->__begin_ + (__position - begin());
     // We can't compare unrelated pointers inside constant expressions
     if (!__libcpp_is_constant_evaluated() && this->__end_ < this->__end_cap())
     {
         if (__p == this->__end_)
         {
             __construct_one_at_end(__x);
         }
vector<_Tp, _Allocator>::insert(const_iterator __position, const_reference __x)
     return __make_iter(__p);
 }
 
 template <class _Tp, class _Allocator>
 _LIBCPP_CONSTEXPR_SINCE_CXX20
 typename vector<_Tp, _Allocator>::iterator
 vector<_Tp, _Allocator>::insert(const_iterator __position, value_type&& __x)
 {
-    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(std::addressof(__position)) == this,
-                         "vector::insert(iterator, x) called with an iterator not referring to this vector");
     pointer __p = this->__begin_ + (__position - begin());
     if (this->__end_ < this->__end_cap())
     {
         if (__p == this->__end_)
         {
             __construct_one_at_end(std::move(__x));
         }
         else

 }
 
 template <class _Tp, class _Allocator>
 template <class... _Args>
 _LIBCPP_CONSTEXPR_SINCE_CXX20
 typename vector<_Tp, _Allocator>::iterator
 vector<_Tp, _Allocator>::emplace(const_iterator __position, _Args&&... __args)
 {
-    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(std::addressof(__position)) == this,
-                         "vector::emplace(iterator, x) called with an iterator not referring to this vector");
     pointer __p = this->__begin_ + (__position - begin());
     if (this->__end_ < this->__end_cap())
     {
         if (__p == this->__end_)
         {
             __construct_one_at_end(std::forward<_Args>(__args)...);
         }
         else
vector<_Tp, _Allocator>::emplace(const_iterator __position, _Args&&... __args)
     return __make_iter(__p);
 }
 
 template <class _Tp, class _Allocator>
 _LIBCPP_CONSTEXPR_SINCE_CXX20
 typename vector<_Tp, _Allocator>::iterator
 vector<_Tp, _Allocator>::insert(const_iterator __position, size_type __n, const_reference __x)
 {
-    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(std::addressof(__position)) == this,
-                         "vector::insert(iterator, n, x) called with an iterator not referring to this vector");
     pointer __p = this->__begin_ + (__position - begin());
     if (__n > 0)
     {
         // We can't compare unrelated pointers inside constant expressions
         if (!__libcpp_is_constant_evaluated() && __n <= static_cast<size_type>(this->__end_cap() - this->__end_))
         {
             size_type __old_n = __n;
             pointer __old_last = this->__end_;
vector<_Tp, _Allocator>::insert(const_iterator __position, _InputIterator __first, _InputIterator __last)
   return __insert_with_sentinel(__position, __first, __last);
 }
 
 template <class _Tp, class _Allocator>
 template <class _InputIterator, class _Sentinel>
 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
 typename vector<_Tp, _Allocator>::iterator
 vector<_Tp, _Allocator>::__insert_with_sentinel(const_iterator __position, _InputIterator __first, _Sentinel __last) {
-  _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(std::addressof(__position)) == this,
-                        "vector::insert called with an iterator not referring to this vector");
-
     difference_type __off = __position - begin();
     pointer __p = this->__begin_ + __off;
     allocator_type& __a = this->__alloc();
     pointer __old_last = this->__end_;
     for (; this->__end_ != this->__end_cap() && __first != __last; ++__first)
     {
         __construct_one_at_end(*__first);
     }

 }
 
 template <class _Tp, class _Allocator>
 template <class _Iterator, class _Sentinel>
 _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
 typename vector<_Tp, _Allocator>::iterator
 vector<_Tp, _Allocator>::__insert_with_size(const_iterator __position, _Iterator __first, _Sentinel __last,
                                             difference_type __n) {
-    _LIBCPP_DEBUG_ASSERT(__get_const_db()->__find_c_from_i(std::addressof(__position)) == this,
-                        "vector::insert called with an iterator not referring to this vector");
-
     auto __insertion_size = __n;
     pointer __p = this->__begin_ + (__position - begin());
     if (__n > 0)
     {
         if (__n <= this->__end_cap() - this->__end_)
         {
             size_type __old_n = __n;
             pointer __old_last = this->__end_;
_LIBCPP_ASSERT(__alloc_traits::propagate_on_container_swap::value ||
                    this->__alloc() == __x.__alloc(),
                    "vector::swap: Either propagate_on_container_swap must be true"
                    " or the allocators must compare equal");
     std::swap(this->__begin_, __x.__begin_);
     std::swap(this->__end_, __x.__end_);
     std::swap(this->__end_cap(), __x.__end_cap());
     std::__swap_allocator(this->__alloc(), __x.__alloc(),
         integral_constant<bool,__alloc_traits::propagate_on_container_swap::value>());
-    std::__debug_db_swap(this, std::addressof(__x));
 }
 
 template <class _Tp, class _Allocator>
 _LIBCPP_CONSTEXPR_SINCE_CXX20
 bool
 vector<_Tp, _Allocator>::__invariants() const
 {
     if (this->__begin_ == nullptr)
     {
         if (this->__end_ != nullptr || this->__end_cap() != nullptr)
             return false;
     }
     else
     {
         if (this->__begin_ > this->__end_)
             return false;
         if (this->__begin_ == this->__end_cap())
             return false;
         if (this->__end_ > this->__end_cap())
             return false;
     }
     return true;
 }
 
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-
-template <class _Tp, class _Allocator>
-bool
-vector<_Tp, _Allocator>::__dereferenceable(const const_iterator* __i) const
-{
-    return this->__begin_ <= __i->base() && __i->base() < this->__end_;
-}
-
-template <class _Tp, class _Allocator>
-bool
-vector<_Tp, _Allocator>::__decrementable(const const_iterator* __i) const
-{
-    return this->__begin_ < __i->base() && __i->base() <= this->__end_;
-}
-
-template <class _Tp, class _Allocator>
-bool
-vector<_Tp, _Allocator>::__addable(const const_iterator* __i, ptrdiff_t __n) const
-{
-    const_pointer __p = __i->base() + __n;
-    return this->__begin_ <= __p && __p <= this->__end_;
-}
-
-template <class _Tp, class _Allocator>
-bool
-vector<_Tp, _Allocator>::__subscriptable(const const_iterator* __i, ptrdiff_t __n) const
-{
-    const_pointer __p = __i->base() + __n;
-    return this->__begin_ <= __p && __p < this->__end_;
-}
-
-#endif // _LIBCPP_ENABLE_DEBUG_MODE
-
-template <class _Tp, class _Allocator>
-inline _LIBCPP_HIDE_FROM_ABI
-void
-vector<_Tp, _Allocator>::__invalidate_iterators_past(pointer __new_last) {
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-  __c_node* __c = __get_db()->__find_c_and_lock(this);
-  for (__i_node** __p = __c->end_; __p != __c->beg_; ) {
-    --__p;
-    const_iterator* __i = static_cast<const_iterator*>((*__p)->__i_);
-    if (__i->base() > __new_last) {
-      (*__p)->__c_ = nullptr;
-      if (--__c->end_ != __p)
-        std::memmove(__p, __p+1, (__c->end_ - __p)*sizeof(__i_node*));
-    }
-  }
-  __get_db()->unlock();
-#else
-  ((void)__new_last);
-#endif
-}
-
 // vector<bool>
 
 template <class _Allocator> class vector<bool, _Allocator>;
 
 template <class _Allocator> struct hash<vector<bool, _Allocator> >;
 
 template <class _Allocator>
 struct __has_storage_type<vector<bool, _Allocator> >

 private:
   class __destroy_vector {
     public:
       _LIBCPP_CONSTEXPR _LIBCPP_HIDE_FROM_ABI __destroy_vector(vector& __vec) : __vec_(__vec) {}
 
       _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void operator()() {
         if (__vec_.__begin_ != nullptr)
             __storage_traits::deallocate(__vec_.__alloc(), __vec_.__begin_, __vec_.__cap());
-        std::__debug_db_invalidate_all(this);
       }
 
     private:
       vector& __vec_;
   };
 
 public:
   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 ~vector() { __destroy_vector(*this)(); }
#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
       try {
 #endif // _LIBCPP_HAS_NO_EXCEPTIONS
         for (; __first != __last; ++__first)
             push_back(*__first);
 #ifndef _LIBCPP_HAS_NO_EXCEPTIONS
       } catch (...) {
         if (__begin_ != nullptr)
           __storage_traits::deallocate(__alloc(), __begin_, __cap());
-        std::__debug_db_invalidate_all(this);
         throw;
       }
 #endif // _LIBCPP_HAS_NO_EXCEPTIONS
     }
 
   template <class _Iterator, class _Sentinel>
   _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
   void __assign_with_sentinel(_Iterator __first, _Sentinel __last);

 
 template <class _Allocator>
 _LIBCPP_CONSTEXPR_SINCE_CXX20 void
 vector<bool, _Allocator>::__vdeallocate() _NOEXCEPT
 {
     if (this->__begin_ != nullptr)
     {
         __storage_traits::deallocate(this->__alloc(), this->__begin_, __cap());
-        std::__debug_db_invalidate_all(this);
         this->__begin_ = nullptr;
         this->__size_ = this->__cap() = 0;
     }
 }
 
 template <class _Allocator>
 _LIBCPP_CONSTEXPR_SINCE_CXX20
 typename vector<bool, _Allocator>::size_type
if (__n > 0)
         {
             vector __v(get_allocator());
             __v.reserve(__recommend(__n));
             __v.__size_ = __n;
             swap(__v);
         }
         std::fill_n(begin(), __n, __x);
     }
-    std::__debug_db_invalidate_all(this);
 }
 
 template <class _Allocator>
 template <class _InputIterator>
 _LIBCPP_CONSTEXPR_SINCE_CXX20 typename enable_if <__has_exactly_input_iterator_category<_InputIterator>::value,
    void
 >::type
 vector<bool, _Allocator>::assign(_InputIterator __first, _InputIterator __last)
vector<bool, _Allocator>::reserve(size_type __n)
     if (__n > capacity())
     {
         if (__n > max_size())
             this->__throw_length_error();
         vector __v(this->get_allocator());
         __v.__vallocate(__n);
         __v.__construct_at_end(this->begin(), this->end(), this->size());
         swap(__v);
-        std::__debug_db_invalidate_all(this);
     }
 }
 
 template <class _Allocator>
 _LIBCPP_CONSTEXPR_SINCE_CXX20 void
 vector<bool, _Allocator>::shrink_to_fit() _NOEXCEPT
 {
     if (__external_cap_to_internal(size()) > __cap())

libcxx/src/CMakeLists.txt

set(LIBCXX_SOURCES
   thread.cpp
   typeinfo.cpp
   valarray.cpp
   variant.cpp
   vector.cpp
   verbose_abort.cpp
   )
 
-if (LIBCXX_ENABLE_DEBUG_MODE OR LIBCXX_ENABLE_BACKWARDS_COMPATIBILITY_DEBUG_MODE_SYMBOLS)
-  list(APPEND LIBCXX_SOURCES
-    debug.cpp
-    legacy_debug_handler.cpp
-    )
-endif()
-
 if (LIBCXX_ENABLE_RANDOM_DEVICE)
   list(APPEND LIBCXX_SOURCES
     random.cpp
     )
 endif()
 
 if (LIBCXX_ENABLE_LOCALIZATION)
   list(APPEND LIBCXX_SOURCES

libcxx/src/debug.cpp

-//===----------------------------------------------------------------------===//
-//
-// 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
-//
-//===----------------------------------------------------------------------===//
-
-#include <__assert>
-#include <__config>
-#include <__debug>
-#include <__hash_table>
-#include <algorithm>
-#include <cstdio>
-#include <functional>
-#include <string>
-
-#ifndef _LIBCPP_HAS_NO_THREADS
-#  include <mutex>
-#  if defined(__ELF__) && defined(_LIBCPP_LINK_PTHREAD_LIB)
-#    pragma comment(lib, "pthread")
-#  endif
-#endif
-
-_LIBCPP_BEGIN_NAMESPACE_STD
-
-_LIBCPP_EXPORTED_FROM_ABI
-__libcpp_db*
-__get_db()
-{
-    static _LIBCPP_NO_DESTROY __libcpp_db db;
-    return &db;
-}
-
-_LIBCPP_EXPORTED_FROM_ABI
-const __libcpp_db*
-__get_const_db()
-{
-    return __get_db();
-}
-
-namespace
-{
-
-#ifndef _LIBCPP_HAS_NO_THREADS
-typedef mutex mutex_type;
-typedef lock_guard<mutex_type> WLock;
-typedef lock_guard<mutex_type> RLock;
-
-mutex_type&
-mut()
-{
-    static _LIBCPP_NO_DESTROY mutex_type m;
-    return m;
-}
-#endif // !_LIBCPP_HAS_NO_THREADS
-
-}  // unnamed namespace
-
-__i_node::~__i_node()
-{
-    if (__next_)
-    {
-        __next_->~__i_node();
-        free(__next_);
-    }
-}
-
-__c_node::~__c_node()
-{
-    free(beg_);
-    if (__next_)
-    {
-        __next_->~__c_node();
-        free(__next_);
-    }
-}
-
-__libcpp_db::__libcpp_db()
-    : __cbeg_(nullptr),
-      __cend_(nullptr),
-      __csz_(0),
-      __ibeg_(nullptr),
-      __iend_(nullptr),
-      __isz_(0)
-{
-}
-
-__libcpp_db::~__libcpp_db()
-{
-    if (__cbeg_)
-    {
-        for (__c_node** p = __cbeg_; p != __cend_; ++p)
-        {
-            if (*p != nullptr)
-            {
-                (*p)->~__c_node();
-                free(*p);
-            }
-        }
-        free(__cbeg_);
-    }
-    if (__ibeg_)
-    {
-        for (__i_node** p = __ibeg_; p != __iend_; ++p)
-        {
-            if (*p != nullptr)
-            {
-                (*p)->~__i_node();
-                free(*p);
-            }
-        }
-        free(__ibeg_);
-    }
-}
-
-void*
-__libcpp_db::__find_c_from_i(void* __i) const
-{
-#ifndef _LIBCPP_HAS_NO_THREADS
-    RLock _(mut());
-#endif
-    __i_node* i = __find_iterator(__i);
-    _LIBCPP_ASSERT(i != nullptr, "iterator not found in debug database.");
-    return i->__c_ != nullptr ? i->__c_->__c_ : nullptr;
-}
-
-void
-__libcpp_db::__insert_ic(void* __i, const void* __c)
-{
-#ifndef _LIBCPP_HAS_NO_THREADS
-    WLock _(mut());
-#endif
-    if (__cbeg_ == __cend_)
-        return;
-    size_t hc = hash<const void*>()(__c) % static_cast<size_t>(__cend_ - __cbeg_);
-    __c_node* c = __cbeg_[hc];
-    if (c == nullptr)
-        return;
-    while (c->__c_ != __c)
-    {
-        c = c->__next_;
-        if (c == nullptr)
-            return;
-    }
-    __i_node* i = __insert_iterator(__i);
-    c->__add(i);
-    i->__c_ = c;
-}
-
-void
-__libcpp_db::__insert_c(void* __c, __libcpp_db::_InsertConstruct *__fn)
-{
-#ifndef _LIBCPP_HAS_NO_THREADS
-    WLock _(mut());
-#endif
-    if (__csz_ + 1 > static_cast<size_t>(__cend_ - __cbeg_))
-    {
-        size_t nc = __next_prime(2*static_cast<size_t>(__cend_ - __cbeg_) + 1);
-        __c_node** cbeg = static_cast<__c_node**>(calloc(nc, sizeof(__c_node*)));
-        if (cbeg == nullptr)
-            __throw_bad_alloc();
-
-        for (__c_node** p = __cbeg_; p != __cend_; ++p)
-        {
-            __c_node* q = *p;
-            while (q != nullptr)
-            {
-                size_t h = hash<void*>()(q->__c_) % nc;
-                __c_node* r = q->__next_;
-                q->__next_ = cbeg[h];
-                cbeg[h] = q;
-                q = r;
-            }
-        }
-        free(__cbeg_);
-        __cbeg_ = cbeg;
-        __cend_ = __cbeg_ + nc;
-    }
-    size_t hc = hash<void*>()(__c) % static_cast<size_t>(__cend_ - __cbeg_);
-    __c_node* p = __cbeg_[hc];
-    void *buf = malloc(sizeof(__c_node));
-    if (buf == nullptr)
-      __throw_bad_alloc();
-    __cbeg_[hc] = __fn(buf, __c, p);
-
-    ++__csz_;
-}
-
-void
-__libcpp_db::__erase_i(void* __i)
-{
-#ifndef _LIBCPP_HAS_NO_THREADS
-    WLock _(mut());
-#endif
-    if (__ibeg_ != __iend_)
-    {
-        size_t hi = hash<void*>()(__i) % static_cast<size_t>(__iend_ - __ibeg_);
-        __i_node* p = __ibeg_[hi];
-        if (p != nullptr)
-        {
-            __i_node* q = nullptr;
-            while (p->__i_ != __i)
-            {
-                q = p;
-                p = p->__next_;
-                if (p == nullptr)
-                    return;
-            }
-            if (q == nullptr)
-                __ibeg_[hi] = p->__next_;
-            else
-                q->__next_ = p->__next_;
-            __c_node* c = p->__c_;
-            --__isz_;
-            if (c != nullptr)
-                c->__remove(p);
-            free(p);
-        }
-    }
-}
-
-void
-__libcpp_db::__invalidate_all(void* __c)
-{
-#ifndef _LIBCPP_HAS_NO_THREADS
-    WLock _(mut());
-#endif
-    if (__cend_ != __cbeg_)
-    {
-        size_t hc = hash<void*>()(__c) % static_cast<size_t>(__cend_ - __cbeg_);
-        __c_node* p = __cbeg_[hc];
-        if (p == nullptr)
-            return;
-        while (p->__c_ != __c)
-        {
-            p = p->__next_;
-            if (p == nullptr)
-                return;
-        }
-        while (p->end_ != p->beg_)
-        {
-            --p->end_;
-            (*p->end_)->__c_ = nullptr;
-        }
-    }
-}
-
-__c_node*
-__libcpp_db::__find_c_and_lock(void* __c) const
-{
-#ifndef _LIBCPP_HAS_NO_THREADS
-    mut().lock();
-#endif
-    if (__cend_ == __cbeg_)
-    {
-#ifndef _LIBCPP_HAS_NO_THREADS
-        mut().unlock();
-#endif
-        return nullptr;
-    }
-    size_t hc = hash<void*>()(__c) % static_cast<size_t>(__cend_ - __cbeg_);
-    __c_node* p = __cbeg_[hc];
-    if (p == nullptr)
-    {
-#ifndef _LIBCPP_HAS_NO_THREADS
-        mut().unlock();
-#endif
-        return nullptr;
-    }
-    while (p->__c_ != __c)
-    {
-        p = p->__next_;
-        if (p == nullptr)
-        {
-#ifndef _LIBCPP_HAS_NO_THREADS
-            mut().unlock();
-#endif
-            return nullptr;
-        }
-    }
-    return p;
-}
-
-__c_node*
-__libcpp_db::__find_c(void* __c) const
-{
-    size_t hc = hash<void*>()(__c) % static_cast<size_t>(__cend_ - __cbeg_);
-    __c_node* p = __cbeg_[hc];
-    _LIBCPP_ASSERT(p != nullptr, "debug mode internal logic error __find_c A");
-    while (p->__c_ != __c)
-    {
-        p = p->__next_;
-        _LIBCPP_ASSERT(p != nullptr, "debug mode internal logic error __find_c B");
-    }
-    return p;
-}
-
-void
-__libcpp_db::unlock() const
-{
-#ifndef _LIBCPP_HAS_NO_THREADS
-    mut().unlock();
-#endif
-}
-
-void
-__libcpp_db::__erase_c(void* __c)
-{
-#ifndef _LIBCPP_HAS_NO_THREADS
-    WLock _(mut());
-#endif
-    if (__cend_ != __cbeg_)
-    {
-        size_t hc = hash<void*>()(__c) % static_cast<size_t>(__cend_ - __cbeg_);
-        __c_node* p = __cbeg_[hc];
-        if (p == nullptr)
-            return;
-        __c_node* q = nullptr;
-        _LIBCPP_ASSERT(p != nullptr, "debug mode internal logic error __erase_c A");
-        while (p->__c_ != __c)
-        {
-            q = p;
-            p = p->__next_;
-            if (p == nullptr)
-                return;
-            _LIBCPP_ASSERT(p != nullptr, "debug mode internal logic error __erase_c B");
-        }
-        if (q == nullptr)
-            __cbeg_[hc] = p->__next_;
-        else
-            q->__next_ = p->__next_;
-        while (p->end_ != p->beg_)
-        {
-            --p->end_;
-            (*p->end_)->__c_ = nullptr;
-        }
-        free(p->beg_);
-        free(p);
-        --__csz_;
-    }
-}
-
-void
-__libcpp_db::__iterator_copy(void* __i, const void* __i0)
-{
-#ifndef _LIBCPP_HAS_NO_THREADS
-    WLock _(mut());
-#endif
-    __i_node* i = __find_iterator(__i);
-    __i_node* i0 = __find_iterator(__i0);
-    __c_node* c0 = i0 != nullptr ? i0->__c_ : nullptr;
-    if (i == nullptr && i0 != nullptr)
-        i = __insert_iterator(__i);
-    __c_node* c = i != nullptr ? i->__c_ : nullptr;
-    if (c != c0)
-    {
-        if (c != nullptr)
-            c->__remove(i);
-        if (i != nullptr)
-        {
-            i->__c_ = nullptr;
-            if (c0 != nullptr)
-            {
-                i->__c_ = c0;
-                i->__c_->__add(i);
-            }
-        }
-    }
-}
-
-bool
-__libcpp_db::__dereferenceable(const void* __i) const
-{
-#ifndef _LIBCPP_HAS_NO_THREADS
-    RLock _(mut());
-#endif
-    __i_node* i = __find_iterator(__i);
-    return i != nullptr && i->__c_ != nullptr && i->__c_->__dereferenceable(__i);
-}
-
-bool
-__libcpp_db::__decrementable(const void* __i) const
-{
-#ifndef _LIBCPP_HAS_NO_THREADS
-    RLock _(mut());
-#endif
-    __i_node* i = __find_iterator(__i);
-    return i != nullptr && i->__c_ != nullptr && i->__c_->__decrementable(__i);
-}
-
-bool
-__libcpp_db::__addable(const void* __i, ptrdiff_t __n) const
-{
-#ifndef _LIBCPP_HAS_NO_THREADS
-    RLock _(mut());
-#endif
-    __i_node* i = __find_iterator(__i);
-    return i != nullptr && i->__c_ != nullptr && i->__c_->__addable(__i, __n);
-}
-
-bool
-__libcpp_db::__subscriptable(const void* __i, ptrdiff_t __n) const
-{
-#ifndef _LIBCPP_HAS_NO_THREADS
-    RLock _(mut());
-#endif
-    __i_node* i = __find_iterator(__i);
-    return i != nullptr && i->__c_ != nullptr && i->__c_->__subscriptable(__i, __n);
-}
-
-bool
-__libcpp_db::__less_than_comparable(const void* __i, const void* __j) const
-{
-#ifndef _LIBCPP_HAS_NO_THREADS
-    RLock _(mut());
-#endif
-    __i_node* i = __find_iterator(__i);
-    __i_node* j = __find_iterator(__j);
-    __c_node* ci = i != nullptr ? i->__c_ : nullptr;
-    __c_node* cj = j != nullptr ? j->__c_ : nullptr;
-    return ci == cj;
-}
-
-void
-__libcpp_db::swap(void* c1, void* c2)
-{
-#ifndef _LIBCPP_HAS_NO_THREADS
-    WLock _(mut());
-#endif
-    size_t hc = hash<void*>()(c1) % static_cast<size_t>(__cend_ - __cbeg_);
-    __c_node* p1 = __cbeg_[hc];
-    _LIBCPP_ASSERT(p1 != nullptr, "debug mode internal logic error swap A");
-    while (p1->__c_ != c1)
-    {
-        p1 = p1->__next_;
-        _LIBCPP_ASSERT(p1 != nullptr, "debug mode internal logic error swap B");
-    }
-    hc = hash<void*>()(c2) % static_cast<size_t>(__cend_ - __cbeg_);
-    __c_node* p2 = __cbeg_[hc];
-    _LIBCPP_ASSERT(p2 != nullptr, "debug mode internal logic error swap C");
-    while (p2->__c_ != c2)
-    {
-        p2 = p2->__next_;
-        _LIBCPP_ASSERT(p2 != nullptr, "debug mode internal logic error swap D");
-    }
-    std::swap(p1->beg_, p2->beg_);
-    std::swap(p1->end_, p2->end_);
-    std::swap(p1->cap_, p2->cap_);
-    for (__i_node** p = p1->beg_; p != p1->end_; ++p)
-        (*p)->__c_ = p1;
-    for (__i_node** p = p2->beg_; p != p2->end_; ++p)
-        (*p)->__c_ = p2;
-}
-
-void
-__libcpp_db::__insert_i(void* __i)
-{
-#ifndef _LIBCPP_HAS_NO_THREADS
-    WLock _(mut());
-#endif
-    __insert_iterator(__i);
-}
-
-void
-__c_node::__add(__i_node* i)
-{
-    if (end_ == cap_)
-    {
-        size_t nc = 2*static_cast<size_t>(cap_ - beg_);
-        if (nc == 0)
-            nc = 1;
-        __i_node** beg =
-           static_cast<__i_node**>(malloc(nc * sizeof(__i_node*)));
-        if (beg == nullptr)
-            __throw_bad_alloc();
-
-        if (nc > 1)
-            memcpy(beg, beg_, nc/2*sizeof(__i_node*));
-        free(beg_);
-        beg_ = beg;
-        end_ = beg_ + nc/2;
-        cap_ = beg_ + nc;
-    }
-    *end_++ = i;
-}
-
-// private api
-
-_LIBCPP_HIDDEN
-__i_node*
-__libcpp_db::__insert_iterator(void* __i)
-{
-    if (__isz_ + 1 > static_cast<size_t>(__iend_ - __ibeg_))
-    {
-        size_t nc = __next_prime(2*static_cast<size_t>(__iend_ - __ibeg_) + 1);
-        __i_node** ibeg = static_cast<__i_node**>(calloc(nc, sizeof(__i_node*)));
-        if (ibeg == nullptr)
-            __throw_bad_alloc();
-
-        for (__i_node** p = __ibeg_; p != __iend_; ++p)
-        {
-            __i_node* q = *p;
-            while (q != nullptr)
-            {
-                size_t h = hash<void*>()(q->__i_) % nc;
-                __i_node* r = q->__next_;
-                q->__next_ = ibeg[h];
-                ibeg[h] = q;
-                q = r;
-            }
-        }
-        free(__ibeg_);
-        __ibeg_ = ibeg;
-        __iend_ = __ibeg_ + nc;
-    }
-    size_t hi = hash<void*>()(__i) % static_cast<size_t>(__iend_ - __ibeg_);
-    __i_node* p = __ibeg_[hi];
-    __i_node* r = __ibeg_[hi] =
-      static_cast<__i_node*>(malloc(sizeof(__i_node)));
-    if (r == nullptr)
-        __throw_bad_alloc();
-
-    ::new(r) __i_node(__i, p, nullptr);
-    ++__isz_;
-    return r;
-}
-
-_LIBCPP_HIDDEN
-__i_node*
-__libcpp_db::__find_iterator(const void* __i) const
-{
-    __i_node* r = nullptr;
-    if (__ibeg_ != __iend_)
-    {
-        size_t h = hash<const void*>()(__i) % static_cast<size_t>(__iend_ - __ibeg_);
-        for (__i_node* nd = __ibeg_[h]; nd != nullptr; nd = nd->__next_)
-        {
-            if (nd->__i_ == __i)
-            {
-                r = nd;
-                break;
-            }
-        }
-    }
-    return r;
-}
-
-_LIBCPP_HIDDEN
-void
-__c_node::__remove(__i_node* p)
-{
-    __i_node** r = find(beg_, end_, p);
-    _LIBCPP_ASSERT(r != end_, "debug mode internal logic error __c_node::__remove");
-    if (--end_ != r)
-        memmove(r, r+1, static_cast<size_t>(end_ - r)*sizeof(__i_node*));
-}
-
-_LIBCPP_END_NAMESPACE_STD

libcxx/src/include/ryu/ryu.h

 #define _LIBCPP_SRC_INCLUDE_RYU_RYU_H
 
 // Avoid formatting to keep the changes with the original code minimal.
 // clang-format off
 
 #include <__charconv/chars_format.h>
 #include <__charconv/to_chars_result.h>
 #include <__config>
-#include <__debug>
 #include <__system_error/errc.h>
 #include <cstdint>
 #include <cstring>
 #include <type_traits>
 
 #include "include/ryu/f2s.h"
 #include "include/ryu/d2s.h"
 #include "include/ryu/d2fixed.h"

libcxx/test/libcxx/algorithms/alg.modifying.operations/copy_move_nontrivial.pass.cpp

 //===----------------------------------------------------------------------===//
 //
 // 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
 //
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++03, c++11, c++14, c++17
-// When the debug mode is enabled, we don't unwrap iterators in `std::copy` and similar algorithms so we never get the
-// optimization.
-// UNSUPPORTED: libcpp-has-debug-mode
 // In the modules build, adding another overload of `memmove` doesn't work.
 // UNSUPPORTED: modules-build
 // GCC complains about "ambiguating" `__builtin_memmove`.
 // UNSUPPORTED: gcc
 
 // <algorithm>
 
 #include <cassert>

libcxx/test/libcxx/algorithms/alg.modifying.operations/copy_move_trivial.pass.cpp

 //===----------------------------------------------------------------------===//
 //
 // 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
 //
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++03, c++11, c++14, c++17
-// When the debug mode is enabled, we don't unwrap iterators in `std::copy` and similar algorithms so we don't get this
-// optimization.
-// UNSUPPORTED: libcpp-has-debug-mode
 // In the modules build, adding another overload of `memmove` doesn't work.
 // UNSUPPORTED: modules-build
 // GCC complains about "ambiguating" `__builtin_memmove`.
 // UNSUPPORTED: gcc
 
 // <algorithm>
 
 // These tests check that `std::copy` and `std::move` (including their variations like `copy_n`) forward to

libcxx/test/libcxx/algorithms/alg.sorting/alg.heap.operations/make.heap/complexity.pass.cpp

int main(int, char**)
   // If something changes to make them go a bit up or down, that's probably fine,
   // and we can just update this test.
   // But if they suddenly leap upward, that's a bad thing.
 
   stats = {};
   std::make_heap(v.begin(), v.end());
   assert(stats.copied == 0);
   assert(stats.moved == 153'486);
-#ifndef _LIBCPP_ENABLE_DEBUG_MODE
   assert(stats.compared == 188'285);
-#endif
 
   assert(std::is_heap(v.begin(), v.end()));
 
   return 0;
 }

libcxx/test/libcxx/algorithms/alg.sorting/assert.sort.invalid_comparator.pass.cpp

 //
 // If this is not satisfied, we have seen issues in the past where the std::sort implementation
 // would proceed to do OOB reads. (rdar://106897934).
 // Other algorithms like std::stable_sort, std::sort_heap do not go out of bounds but can produce
 // incorrect results, we also want to assert on that.
 // Sometimes std::sort does not go out of bounds as well, for example, right now if transitivity
 // of equivalence is not met, std::sort can only produce incorrect result but would not fail.
 
-// When the debug mode is enabled, this test fails because we actually catch on the fly that the comparator
-// is not a strict-weak ordering before we catch that we'd dereference out-of-bounds inside std::sort,
-// which leads to different errors than the ones tested below.
-// XFAIL: libcpp-has-debug-mode
-
 #include <algorithm>
 #include <cassert>
 #include <cstddef>
 #include <limits>
 #include <map>
 #include <memory>
 #include <ranges>
 #include <random>

libcxx/test/libcxx/iterators/unwrap_iter.pass.cpp

 //===----------------------------------------------------------------------===//
 //
 // 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
 //
 //===----------------------------------------------------------------------===//
 
-// When the debug mode is enabled, we don't unwrap iterators in std::copy
-// so we don't get this optimization.
-// UNSUPPORTED: libcpp-has-debug-mode
-
 // check that std::__unwrap_iter() returns the correct type
 
 #include <algorithm>
 #include <cassert>
 #include <string>
 #include <type_traits>
 
 #include "test_iterators.h"

libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/sort.heap/complexity.pass.cpp

for (int logn = 10; logn <= 20; ++logn) {
     const int debug_comparisons = 2 * (debug_elements + 1) * debug_elements;
     std::shuffle(first, last, g);
     std::make_heap(first, last);
     // The exact stats of our current implementation are recorded here.
     stats = {};
     std::sort_heap(first, last);
     LIBCPP_ASSERT(stats.copied == 0);
     LIBCPP_ASSERT(stats.moved <= 2 * n + n * logn);
-#ifndef _LIBCPP_ENABLE_DEBUG_MODE
     LIBCPP_ASSERT(stats.compared <= n * logn);
-#endif
     LIBCPP_ASSERT(std::is_sorted(first, last));
     LIBCPP_ASSERT(stats.compared <= 2 * n * logn + debug_comparisons);
   }
   return 0;
 }

libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/sort.heap/ranges_sort_heap.pass.cpp

for (int logn = 10; logn <= 20; ++logn) {
     const int debug_comparisons = 2 * (debug_elements + 1) * debug_elements;
     std::shuffle(first, last, g);
     std::make_heap(first, last, &MyInt::Comp);
     // The exact stats of our current implementation are recorded here.
     stats = {};
     std::ranges::sort_heap(first, last, &MyInt::Comp);
     LIBCPP_ASSERT(stats.copied == 0);
     LIBCPP_ASSERT(stats.moved <= 2 * n + n * logn);
-#ifndef _LIBCPP_ENABLE_DEBUG_MODE
     LIBCPP_ASSERT(stats.compared <= n * logn);
-#endif
     LIBCPP_ASSERT(std::is_sorted(first, last, &MyInt::Comp));
     LIBCPP_ASSERT(stats.compared <= 2 * n * logn + debug_comparisons);
   }
 }
 
 int main(int, char**) {
   test();
   static_assert(test());
   test_complexity();
   return 0;
 }

libcxx/test/std/algorithms/alg.sorting/alg.merge/inplace_merge_comp.pass.cpp

test_one(unsigned N, unsigned M)
     std::sort(ia+M, ia+N, std::greater<value_type>());
     binary_counting_predicate<std::greater<value_type>, value_type, value_type> pred((std::greater<value_type>()));
     std::inplace_merge(Iter(ia), Iter(ia+M), Iter(ia+N), std::ref(pred));
     if(N > 0)
     {
         assert(ia[0] == static_cast<int>(N)-1);
         assert(ia[N-1] == 0);
         assert(std::is_sorted(ia, ia+N, std::greater<value_type>()));
-#ifndef _LIBCPP_ENABLE_DEBUG_MODE
         assert(pred.count() <= (N-1));
-#endif
     }
     delete [] ia;
 }
 
 template <class Iter>
 void
 test(unsigned N)
 {

libcxx/test/std/algorithms/alg.sorting/alg.three.way/lexicographical_compare_three_way_comp.pass.cpp

constexpr void test_comparator_invocation_count() {
   // If one of the ranges is empty, the comparator must not be called at all
   compare_invocation_count = 0;
   test_lexicographical_compare<const int*, const int*>(
       std::array{0, 1, 2, 3}, std::array<int, 0>{}, compare_last_digit_counting, std::strong_ordering::greater);
   assert(compare_invocation_count == 0);
   // The comparator is invoked only `min(left.size(), right.size())` times
   test_lexicographical_compare<const int*, const int*>(
       std::array{0, 1, 2}, std::array{0, 1, 2, 3}, compare_last_digit_counting, std::strong_ordering::less);
-#ifdef _LIBCPP_ENABLE_DEBUG_MODE
-  assert(compare_invocation_count <= 6);
-#else
   assert(compare_invocation_count <= 3);
-#endif
 }
 
 // Check that it works with proxy iterators
 constexpr void test_proxy_iterators() {
     std::vector<bool> vec(10, true);
     auto result = std::lexicographical_compare_three_way(vec.begin(), vec.end(), vec.begin(), vec.end(), compare_last_digit_strong);
     assert(result == std::strong_ordering::equal);
 }

libcxx/test/std/containers/associative/map/map.cons/copy_assign.pass.cpp

 //===----------------------------------------------------------------------===//
 //
 // 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
 //
 //===----------------------------------------------------------------------===//
 
 // <map>
 
 // class map
 
 // map& operator=(const map& m);
 
-// XFAIL: libcpp-has-debug-mode
-
 #include <map>
 #include <algorithm>
 #include <cassert>
 #include <cstdio>
 #include <iterator>
 #include <vector>
 
 #include "test_macros.h"

libcxx/test/std/containers/sequences/vector/constant_initialization.pass.cpp

 //===----------------------------------------------------------------------===//
 //
 // 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
 //
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++03
-// XFAIL: libcpp-has-debug-mode
 
 #include <algorithm>
 #include <vector>
 
 std::vector<int> ca_allocs;
 
 int main(int, char**) {
   ca_allocs.push_back(0);
   for ([[maybe_unused]] const auto& a : ca_allocs)
     ;
 
   return 0;
 }

libcxx/test/support/container_debug_tests.h

 #ifndef _LIBCPP_VERSION
 #error This header may only be used for libc++ tests
 #endif
 
 #ifndef _LIBCPP_ENABLE_DEBUG_MODE
 #error The library must be built with the debug mode enabled in order to use this header
 #endif
 
-#include <__debug>
 #include <utility>
 #include <cstddef>
 #include <cstdlib>
 #include <cassert>
 
 #include "check_assertion.h"
 #include "test_allocator.h"
 #include "test_macros.h"

libcxx/utils/ci/buildkite-pipeline.yml

agents:
       queue: "libcxx-builders"
       os: "linux"
     retry:
       automatic:
         - exit_status: -1  # Agent was lost
           limit: 2
     timeout_in_minutes: 120
 
-  - label: "Debug mode"
-    command: "libcxx/utils/ci/run-buildbot generic-debug-mode"
-    artifact_paths:
-      - "**/test-results.xml"
-      - "**/*.abilist"
-    env:
-        CC: "clang-${LLVM_HEAD_VERSION}"
-        CXX: "clang++-${LLVM_HEAD_VERSION}"
-        ENABLE_CLANG_TIDY: "On"
-    agents:
-      queue: "libcxx-builders"
-      os: "linux"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
   - label: "With LLVM's libunwind"
     command: "libcxx/utils/ci/run-buildbot generic-with_llvm_unwinder"
     artifact_paths:
       - "**/test-results.xml"
       - "**/*.abilist"
     env:
         CC: "clang-${LLVM_HEAD_VERSION}"
         CXX: "clang++-${LLVM_HEAD_VERSION}"

libcxx/utils/ci/run-buildbot

generic-merged)
     check-runtimes
 ;;
 generic-assertions)
     clean
     generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-assertions.cmake"
     check-runtimes
     check-abi-list
 ;;
-generic-debug-mode)
-    clean
-    generate-cmake -C "${MONOREPO_ROOT}/libcxx/cmake/caches/Generic-debug-mode.cmake"
-    check-runtimes
-    # We don't check the ABI lists because the debug mode ABI is not stable
-;;
 generic-with_llvm_unwinder)
     clean
     generate-cmake -DLIBCXXABI_USE_LLVM_UNWINDER=ON
     check-runtimes
 ;;
 #
 # Module builds
 #

libcxx/utils/data/ignore_format.txt

 libcxx/include/condition_variable
 libcxx/include/__coroutine/coroutine_handle.h
 libcxx/include/__coroutine/coroutine_traits.h
 libcxx/include/__coroutine/noop_coroutine_handle.h
 libcxx/include/__coroutine/trivial_awaitables.h
 libcxx/include/cstddef
 libcxx/include/ctype.h
 libcxx/include/cuchar
-libcxx/include/__debug
 libcxx/include/__debug_utils/randomize_range.h
 libcxx/include/deque
 libcxx/include/errno.h
 libcxx/include/expected
 libcxx/include/__expected/expected.h
 libcxx/include/experimental/__config
 libcxx/include/experimental/iterator
 libcxx/include/experimental/map

 libcxx/src/any.cpp
 libcxx/src/atomic.cpp
 libcxx/src/barrier.cpp
 libcxx/src/bind.cpp
 libcxx/src/charconv.cpp
 libcxx/src/chrono.cpp
 libcxx/src/condition_variable.cpp
 libcxx/src/condition_variable_destructor.cpp
-libcxx/src/debug.cpp
 libcxx/src/exception.cpp
 libcxx/src/experimental/memory_resource.cpp
 libcxx/src/filesystem/directory_entry.cpp
 libcxx/src/filesystem/directory_iterator.cpp
 libcxx/src/filesystem/error.h
 libcxx/src/filesystem/file_descriptor.h
 libcxx/src/filesystem/filesystem_clock.cpp
 libcxx/src/filesystem/filesystem_error.cpp

libcxx/utils/gdb/libcxx/printers.py

def __call__(self, val):
         if val.type.strip_typedefs().code != gdb.TYPE_CODE_STRUCT:
             return None
 
         # Don't attempt types known to be inside libstdcxx.
         typename = val.type.name or val.type.tag or str(val.type)
         match = re.match("^std::(__.*?)::", typename)
         if match is not None and match.group(1) in [
             "__cxx1998",
-            "__debug",
             "__7",
             "__g",
         ]:
             return None
 
         # Handle any using declarations or other typedefs.
         typename = _prettify_typename(val.type)
         if not typename:

libcxx/utils/generate_iwyu_mapping.py

for i in detail_files:
         elif i == "__bit_reference":
             continue
         elif i == "__bits":
             public = ["bits"]
         elif i == "__config_site.in":
             continue
         elif i == "__config":
             continue
-        elif i == "__debug":
-            continue
         elif i == "__errc":
             continue
         elif i == "__hash_table":
             public = ["unordered_map", "unordered_set"]
         elif i == "__locale":
             public = ["locale"]
         elif i == "__mbstate_t.h":
             continue

libcxx/utils/libcxx/test/features.py

macros = {
     "_LIBCPP_HAS_THREAD_API_PTHREAD": "libcpp-has-thread-api-pthread",
     "_LIBCPP_NO_VCRUNTIME": "libcpp-no-vcruntime",
     "_LIBCPP_ABI_VERSION": "libcpp-abi-version",
     "_LIBCPP_HAS_NO_FILESYSTEM": "no-filesystem",
     "_LIBCPP_HAS_NO_RANDOM_DEVICE": "no-random-device",
     "_LIBCPP_HAS_NO_LOCALIZATION": "no-localization",
     "_LIBCPP_HAS_NO_WIDE_CHARACTERS": "no-wide-characters",
     "_LIBCPP_HAS_NO_UNICODE": "libcpp-has-no-unicode",
-    "_LIBCPP_ENABLE_DEBUG_MODE": "libcpp-has-debug-mode",
 }
 for macro, feature in macros.items():
     DEFAULT_FEATURES.append(
         Feature(
             name=lambda cfg, m=macro, f=feature: f + ("={}".format(compilerMacros(cfg)[m]) if compilerMacros(cfg)[m] else ""),
             when=lambda cfg, m=macro: m in compilerMacros(cfg),
         )
     )

libcxx/utils/libcxx/test/header_information.py

lit_header_restrictions = {
     "wchar.h": "// UNSUPPORTED: no-wide-characters",
     "wctype.h": "// UNSUPPORTED: no-wide-characters",
 }
 
 private_headers_still_public_in_modules = [
     "__assert",
     "__config",
     "__config_site.in",
-    "__debug",
     "__hash_table",
     "__threading_support",
     "__tree",
     "__undef_macros",
     "__verbose_abort",
 ]
 
 # This table was produced manually, by grepping the TeX source of the Standard's