[libcxx][modularisation] splices `<iterator>` into individual headers

[ldionne]

libcxx/include/CMakeLists.txt

133

Please keep everything sorted.

140–141

Please keep at one level of nesting.

[cjdb]

applies @ldionne's feedback

[cjdb]

The single failure I'm seeing is completely unrelated and has happened on several patches I've made. Since it's thread-related, I'm thinking it might be a race condition?

[ldionne]

LGTM, but please remove the stray whitespace change before committing. Thanks!

libcxx/include/__iterator/wrap_iter.h

16 ↗

(On Diff #356564)

Stray whitespace change.

[mehdi_amini]

I think this breaks the bootstrap of clang somehow:

[491/508] Building CXX object libcxx/src/CMakeFiles/cxx_static.dir/filesystem/directory_iterator.cpp.o
FAILED: libcxx/src/CMakeFiles/cxx_static.dir/filesystem/directory_iterator.cpp.o
/tmp/ci-2ohZKYWbsH/./bin/clang++ --target=x86_64-unknown-linux-gnu -DNDEBUG -D_LIBCPP_BUILDING_LIBRARY -D_LIBCPP_DISABLE_NEW_DELETE_DEFINITIONS -D_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER -D_LIBCPP_LINK_PTHREAD_LIB -D_LIBCPP_LINK_RT_LIB -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -Ilibcxx/include/c++build -fPIC -fno-semantic-interposition -fvisibility-inlines-hidden -Werror=date-time -Werror=unguarded-availability-new -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -Wimplicit-fallthrough -Wcovered-switch-default -Wno-noexcept-type -Wnon-virtual-dtor -Wdelete-non-virtual-dtor -Wsuggest-override -Wno-comment -Wstring-conversion -Wmisleading-indentation -fdiagnostics-color -ffunction-sections -fdata-sections -O3  -DLIBCXX_BUILDING_LIBCXXABI -faligned-allocation -nostdinc++ -fvisibility-inlines-hidden -fvisibility=hidden -Wall -Wextra -W -Wwrite-strings -Wno-unused-parameter -Wno-long-long -Werror=return-type -Wextra-semi -Wundef -Wno-user-defined-literals -Wno-covered-switch-default -Wno-suggest-override -Wno-ignored-attributes -Wno-error -I/tmp/ci-2ohZKYWbsH/include/c++/v1 -I/tmp/ci-2ohZKYWbsH/include/x86_64-unknown-linux-gnu/c++/v1 -std=c++20 -MD -MT libcxx/src/CMakeFiles/cxx_static.dir/filesystem/directory_iterator.cpp.o -MF libcxx/src/CMakeFiles/cxx_static.dir/filesystem/directory_iterator.cpp.o.d -o libcxx/src/CMakeFiles/cxx_static.dir/filesystem/directory_iterator.cpp.o -c /var/lib/buildkite-agent/builds/buildkite-74bcfb76f5-mkp7s-1/mlir/mlir-core/libcxx/src/filesystem/directory_iterator.cpp
PLEASE submit a bug report to https://bugs.llvm.org/ and include the crash backtrace, preprocessed source, and associated run script.
Stack dump:
0.	Program arguments: /tmp/ci-2ohZKYWbsH/./bin/clang++ --target=x86_64-unknown-linux-gnu -DNDEBUG -D_LIBCPP_BUILDING_LIBRARY -D_LIBCPP_DISABLE_NEW_DELETE_DEFINITIONS -D_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER -D_LIBCPP_LINK_PTHREAD_LIB -D_LIBCPP_LINK_RT_LIB -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -Ilibcxx/include/c++build -fPIC -fno-semantic-interposition -fvisibility-inlines-hidden -Werror=date-time -Werror=unguarded-availability-new -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -Wimplicit-fallthrough -Wcovered-switch-default -Wno-noexcept-type -Wnon-virtual-dtor -Wdelete-non-virtual-dtor -Wsuggest-override -Wno-comment -Wstring-conversion -Wmisleading-indentation -fdiagnostics-color -ffunction-sections -fdata-sections -O3 -DLIBCXX_BUILDING_LIBCXXABI -faligned-allocation -nostdinc++ -fvisibility-inlines-hidden -fvisibility=hidden -Wall -Wextra -W -Wwrite-strings -Wno-unused-parameter -Wno-long-long -Werror=return-type -Wextra-semi -Wundef -Wno-user-defined-literals -Wno-covered-switch-default -Wno-suggest-override -Wno-ignored-attributes -Wno-error -I/tmp/ci-2ohZKYWbsH/include/c++/v1 -I/tmp/ci-2ohZKYWbsH/include/x86_64-unknown-linux-gnu/c++/v1 -std=c++20 -MD -MT libcxx/src/CMakeFiles/cxx_static.dir/filesystem/directory_iterator.cpp.o -MF libcxx/src/CMakeFiles/cxx_static.dir/filesystem/directory_iterator.cpp.o.d -o libcxx/src/CMakeFiles/cxx_static.dir/filesystem/directory_iterator.cpp.o -c /var/lib/buildkite-agent/builds/buildkite-74bcfb76f5-mkp7s-1/mlir/mlir-core/libcxx/src/filesystem/directory_iterator.cpp
1.	<eof> parser at end of file
2.	Optimizer
Stack dump without symbol names (ensure you have llvm-symbolizer in your PATH or set the environment var `LLVM_SYMBOLIZER_PATH` to point to it):
/tmp/ci-2ohZKYWbsH/./bin/clang++(_ZN4llvm3sys15PrintStackTraceERNS_11raw_ostreamEi+0x23)[0x2eac243]
/tmp/ci-2ohZKYWbsH/./bin/clang++(_ZN4llvm3sys17RunSignalHandlersEv+0xee)[0x2eaa0ae]
/tmp/ci-2ohZKYWbsH/./bin/clang++(_ZN4llvm3sys15CleanupOnSignalEm+0xe2)[0x2eab6d2]
/tmp/ci-2ohZKYWbsH/./bin/clang++[0x2e1f2bf]
/lib/x86_64-linux-gnu/libpthread.so.0(+0x12980)[0x7f1660d5f980]
/tmp/ci-2ohZKYWbsH/./bin/clang++[0x1b6b48b]
/tmp/ci-2ohZKYWbsH/./bin/clang++(_ZN4llvm16MemoryDepChecker11isDependentERKNS_14PointerIntPairIPNS_5ValueELj1EbNS_21PointerLikeTypeTraitsIS3_EENS_18PointerIntPairInfoIS3_Lj1ES5_EEEEjSA_jRKNS_8DenseMapIPKS2_S3_NS_12DenseMapInfoISD_EENS_6detail12DenseMapPairISD_S3_EEEE+0x360)[0x22d9e60]
/tmp/ci-2ohZKYWbsH/./bin/clang++(_ZN4llvm16MemoryDepChecker11areDepsSafeERNS_18EquivalenceClassesINS_14PointerIntPairIPNS_5ValueELj1EbNS_21PointerLikeTypeTraitsIS4_EENS_18PointerIntPairInfoIS4_Lj1ES6_EEEEEERNS_11SmallVectorIS9_Lj8EEERKNS_8DenseMapIPKS3_S4_NS_12DenseMapInfoISH_EENS_6detail12DenseMapPairISH_S4_EEEE+0x6e4)[0x22da9a4]
/tmp/ci-2ohZKYWbsH/./bin/clang++(_ZN4llvm14LoopAccessInfo11analyzeLoopEPNS_9AAResultsEPNS_8LoopInfoEPKNS_17TargetLibraryInfoEPNS_13DominatorTreeE+0x1733)[0x22dc7c3]
/tmp/ci-2ohZKYWbsH/./bin/clang++(_ZN4llvm18LoopAccessAnalysis3runERNS_4LoopERNS_15AnalysisManagerIS1_JRNS_27LoopStandardAnalysisResultsEEEES5_+0x2d)[0x22deb2d]
/tmp/ci-2ohZKYWbsH/./bin/clang++[0x3e194e5]
/tmp/ci-2ohZKYWbsH/./bin/clang++(_ZN4llvm15AnalysisManagerINS_4LoopEJRNS_27LoopStandardAnalysisResultsEEE13getResultImplEPNS_11AnalysisKeyERS1_S3_+0x2d2)[0x2c38b02]
/tmp/ci-2ohZKYWbsH/./bin/clang++[0x302f474]
/tmp/ci-2ohZKYWbsH/./bin/clang++(_ZN4llvm25LoopVectorizationLegality18canVectorizeMemoryEv+0x28)[0x3035998]
/tmp/ci-2ohZKYWbsH/./bin/clang++(_ZN4llvm25LoopVectorizationLegality12canVectorizeEb+0x156)[0x3037186]
/tmp/ci-2ohZKYWbsH/./bin/clang++(_ZN4llvm17LoopVectorizePass11processLoopEPNS_4LoopE+0x2a8)[0x301be18]
/tmp/ci-2ohZKYWbsH/./bin/clang++(_ZN4llvm17LoopVectorizePass7runImplERNS_8FunctionERNS_15ScalarEvolutionERNS_8LoopInfoERNS_19TargetTransformInfoERNS_13DominatorTreeERNS_18BlockFrequencyInfoEPNS_17TargetLibraryInfoERNS_12DemandedBitsERNS_9AAResultsERNS_15AssumptionCacheERSt8functionIFRKNS_14LoopAccessInfoERNS_4LoopEEERNS_25OptimizationRemarkEmitterEPNS_18ProfileSummaryInfoE+0x1a7)[0x3021647]
/tmp/ci-2ohZKYWbsH/./bin/clang++(_ZN4llvm17LoopVectorizePass3runERNS_8FunctionERNS_15AnalysisManagerIS1_JEEE+0x2aa)[0x3021b1a]
/tmp/ci-2ohZKYWbsH/./bin/clang++[0x3e2c63d]
/tmp/ci-2ohZKYWbsH/./bin/clang++(_ZN4llvm11PassManagerINS_8FunctionENS_15AnalysisManagerIS1_JEEEJEE3runERS1_RS3_+0x17c)[0x27bf35c]
/tmp/ci-2ohZKYWbsH/./bin/clang++[0x1daa21d]
/tmp/ci-2ohZKYWbsH/./bin/clang++(_ZN4llvm27ModuleToFunctionPassAdaptor3runERNS_6ModuleERNS_15AnalysisManagerIS1_JEEE+0x1a3)[0x27c2493]
/tmp/ci-2ohZKYWbsH/./bin/clang++[0x1daa09d]
/tmp/ci-2ohZKYWbsH/./bin/clang++(_ZN4llvm11PassManagerINS_6ModuleENS_15AnalysisManagerIS1_JEEEJEE3runERS1_RS3_+0x189)[0x27be509]
/tmp/ci-2ohZKYWbsH/./bin/clang++[0x30d7638]
/tmp/ci-2ohZKYWbsH/./bin/clang++(_ZN5clang17EmitBackendOutputERNS_17DiagnosticsEngineERKNS_19HeaderSearchOptionsERKNS_14CodeGenOptionsERKNS_13TargetOptionsERKNS_11LangOptionsEN4llvm9StringRefEPNSE_6ModuleENS_13BackendActionESt10unique_ptrINSE_17raw_pwrite_streamESt14default_deleteISK_EE+0x12ef)[0x30d0f9f]
/tmp/ci-2ohZKYWbsH/./bin/clang++[0x37e2ac2]
/tmp/ci-2ohZKYWbsH/./bin/clang++(_ZN5clang8ParseASTERNS_4SemaEbb+0x273)[0x4621c03]
/tmp/ci-2ohZKYWbsH/./bin/clang++(_ZN5clang14FrontendAction7ExecuteEv+0x10b)[0x37398ab]
/tmp/ci-2ohZKYWbsH/./bin/clang++(_ZN5clang16CompilerInstance13ExecuteActionERNS_14FrontendActionE+0x32b)[0x36a78cb]
/tmp/ci-2ohZKYWbsH/./bin/clang++(_ZN5clang25ExecuteCompilerInvocationEPNS_16CompilerInstanceE+0x659)[0x37ddbd9]
/tmp/ci-2ohZKYWbsH/./bin/clang++(_Z8cc1_mainN4llvm8ArrayRefIPKcEES2_Pv+0x92f)[0x1ad9f3f]
/tmp/ci-2ohZKYWbsH/./bin/clang++[0x1ad8418]
/tmp/ci-2ohZKYWbsH/./bin/clang++[0x3545272]
/tmp/ci-2ohZKYWbsH/./bin/clang++(_ZN4llvm20CrashRecoveryContext9RunSafelyENS_12function_refIFvvEEE+0xd7)[0x2e1f0a7]
/tmp/ci-2ohZKYWbsH/./bin/clang++(_ZNK5clang6driver10CC1Command7ExecuteEN4llvm8ArrayRefINS2_8OptionalINS2_9StringRefEEEEEPNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEEPb+0x139)[0x3544d89]
/tmp/ci-2ohZKYWbsH/./bin/clang++(_ZNK5clang6driver11Compilation14ExecuteCommandERKNS0_7CommandERPS3_+0x196)[0x350f5b6]
/tmp/ci-2ohZKYWbsH/./bin/clang++(_ZNK5clang6driver11Compilation11ExecuteJobsERKNS0_7JobListERN4llvm15SmallVectorImplISt4pairIiPKNS0_7CommandEEEE+0x8a)[0x350fa5a]
/tmp/ci-2ohZKYWbsH/./bin/clang++(_ZN5clang6driver6Driver18ExecuteCompilationERNS0_11CompilationERN4llvm15SmallVectorImplISt4pairIiPKNS0_7CommandEEEE+0x188)[0x35282c8]
/tmp/ci-2ohZKYWbsH/./bin/clang++(main+0x2b17)[0x1ad7e17]
/lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xe7)[0x7f165f7ebbf7]
/tmp/ci-2ohZKYWbsH/./bin/clang++(_start+0x2a)[0x1ad502a]
clang-13: error: clang frontend command failed with exit code 139 (use -v to see invocation)
clang version 13.0.0 (https://github.com/llvm/llvm-project 8517a26d442fa1b3d01e52a83ae76023ba7c9784)
Target: x86_64-unknown-linux-gnu
Thread model: posix
InstalledDir: /tmp/ci-2ohZKYWbsH/./bin

https://buildkite.com/mlir/mlir-core/builds/15006#3b694d67-a3cc-4b56-81d6-19e7bc279570

[cjdb]

Yikes! @ldionne, I'm going to look into this now. @mehdi_amini can you ping me on chat?

[mehdi_amini]

Actually other than this change being about "iterator" and the file crashing clang being libcxx/directory_iterator.cpp, there is no specific link. I'm bisecting the blame list...

[mehdi_amini]

In D105076#2860421, @mehdi_amini wrote:

Actually other than this change being about "iterator" and the file crashing clang being libcxx/directory_iterator.cpp, there is no specific link. I'm bisecting the blame list...

Bisected to https://reviews.llvm.org/D104806 which just got reverted! Sorry for the noise :)

libcxx/include/CMakeLists.txt

set(files
   __functional/pointer_to_unary_function.h
   __functional/ranges_operations.h
   __functional/reference_wrapper.h
   __functional/unary_function.h
   __functional/unary_negate.h
   __functional/unwrap_ref.h
   __functional/weak_result_type.h
   __hash_table
+  __iterator/access.h
   __iterator/advance.h
   __iterator/back_insert_iterator.h
   __iterator/concepts.h
+  __iterator/data.h
   __iterator/default_sentinel.h
+  __iterator/distance.h
+  __iterator/empty.h
+  __iterator/erase_if_container.h
   __iterator/front_insert_iterator.h
   __iterator/incrementable_traits.h
   __iterator/insert_iterator.h
-  __iterator/istream_iterator.h
   __iterator/istreambuf_iterator.h
+  __iterator/istream_iterator.h
+  __iterator/iterator.h
+  __iterator/iterator_traits.h
   __iterator/iter_move.h
   __iterator/iter_swap.h
-  __iterator/iterator_traits.h
-  __iterator/iterator.h
   __iterator/move_iterator.h
   __iterator/next.h
-  __iterator/ostream_iterator.h
   __iterator/ostreambuf_iterator.h
+  __iterator/ostream_iterator.h
   __iterator/prev.h
   __iterator/projected.h
   __iterator/readable_traits.h
+  __iterator/reverse_access.h
   __iterator/reverse_iterator.h
+  __iterator/size.h
   __iterator/wrap_iter.h
   __libcpp_version
   __locale
   __memory/addressof.h
   __memory/allocation_guard.h
   __memory/allocator_arg_t.h
   __memory/allocator_traits.h
   __memory/allocator.h

libcxx/include/__iterator/access.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_ACCESS_H
+#define _LIBCPP___ITERATOR_ACCESS_H
+
+#include <__config>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp, size_t _Np>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
+_Tp*
+begin(_Tp (&__array)[_Np])
+{
+    return __array;
+}
+
+template <class _Tp, size_t _Np>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
+_Tp*
+end(_Tp (&__array)[_Np])
+{
+    return __array + _Np;
+}
+
+#if !defined(_LIBCPP_CXX03_LANG)
+
+template <class _Cp>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+auto
+begin(_Cp& __c) -> decltype(__c.begin())
+{
+    return __c.begin();
+}
+
+template <class _Cp>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+auto
+begin(const _Cp& __c) -> decltype(__c.begin())
+{
+    return __c.begin();
+}
+
+template <class _Cp>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+auto
+end(_Cp& __c) -> decltype(__c.end())
+{
+    return __c.end();
+}
+
+template <class _Cp>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+auto
+end(const _Cp& __c) -> decltype(__c.end())
+{
+    return __c.end();
+}
+
+#if _LIBCPP_STD_VER > 11
+
+template <class _Cp>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
+auto cbegin(const _Cp& __c) -> decltype(_VSTD::begin(__c))
+{
+    return _VSTD::begin(__c);
+}
+
+template <class _Cp>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
+auto cend(const _Cp& __c) -> decltype(_VSTD::end(__c))
+{
+    return _VSTD::end(__c);
+}
+
+#endif
+
+
+#else  // defined(_LIBCPP_CXX03_LANG)
+
+template <class _Cp>
+_LIBCPP_INLINE_VISIBILITY
+typename _Cp::iterator
+begin(_Cp& __c)
+{
+    return __c.begin();
+}
+
+template <class _Cp>
+_LIBCPP_INLINE_VISIBILITY
+typename _Cp::const_iterator
+begin(const _Cp& __c)
+{
+    return __c.begin();
+}
+
+template <class _Cp>
+_LIBCPP_INLINE_VISIBILITY
+typename _Cp::iterator
+end(_Cp& __c)
+{
+    return __c.end();
+}
+
+template <class _Cp>
+_LIBCPP_INLINE_VISIBILITY
+typename _Cp::const_iterator
+end(const _Cp& __c)
+{
+    return __c.end();
+}
+
+#endif // !defined(_LIBCPP_CXX03_LANG)
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ITERATOR_ACCESS_H

libcxx/include/__iterator/back_insert_iterator.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_BACK_INSERT_ITERATOR_H
 #define _LIBCPP___ITERATOR_BACK_INSERT_ITERATOR_H
 
 #include <__config>
-#include <__iterator/iterator_traits.h>
 #include <__iterator/iterator.h>
+#include <__iterator/iterator_traits.h>
 #include <__memory/addressof.h>
+#include <__utility/move.h>
 #include <cstddef>
-#include <utility> // std::move
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #pragma GCC system_header
 #endif
 
 _LIBCPP_PUSH_MACROS
 #include <__undef_macros>
 

libcxx/include/__iterator/data.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_DATA_H
+#define _LIBCPP___ITERATOR_DATA_H
+
+#include <__config>
+#include <cstddef>
+#include <initializer_list>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER > 14
+
+template <class _Cont> constexpr
+_LIBCPP_INLINE_VISIBILITY
+auto data(_Cont& __c)
+_NOEXCEPT_(noexcept(__c.data()))
+-> decltype        (__c.data())
+{ return            __c.data(); }
+
+template <class _Cont> constexpr
+_LIBCPP_INLINE_VISIBILITY
+auto data(const _Cont& __c)
+_NOEXCEPT_(noexcept(__c.data()))
+-> decltype        (__c.data())
+{ return            __c.data(); }
+
+template <class _Tp, size_t _Sz>
+_LIBCPP_INLINE_VISIBILITY
+constexpr _Tp* data(_Tp (&__array)[_Sz]) noexcept { return __array; }
+
+template <class _Ep>
+_LIBCPP_INLINE_VISIBILITY
+constexpr const _Ep* data(initializer_list<_Ep> __il) noexcept { return __il.begin(); }
+
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ITERATOR_DATA_H

libcxx/include/__iterator/distance.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_DISTANCE_H
+#define _LIBCPP___ITERATOR_DISTANCE_H
+
+#include <__config>
+#include <__iterator/iterator_traits.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _InputIter>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+typename iterator_traits<_InputIter>::difference_type
+__distance(_InputIter __first, _InputIter __last, input_iterator_tag)
+{
+    typename iterator_traits<_InputIter>::difference_type __r(0);
+    for (; __first != __last; ++__first)
+        ++__r;
+    return __r;
+}
+
+template <class _RandIter>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+typename iterator_traits<_RandIter>::difference_type
+__distance(_RandIter __first, _RandIter __last, random_access_iterator_tag)
+{
+    return __last - __first;
+}
+
+template <class _InputIter>
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+typename iterator_traits<_InputIter>::difference_type
+distance(_InputIter __first, _InputIter __last)
+{
+    return _VSTD::__distance(__first, __last, typename iterator_traits<_InputIter>::iterator_category());
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ITERATOR_DISTANCE_H

libcxx/include/__iterator/empty.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_EMPTY_H
+#define _LIBCPP___ITERATOR_EMPTY_H
+
+#include <__config>
+#include <cstddef>
+#include <initializer_list>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER > 14
+
+template <class _Cont>
+_LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY
+constexpr auto empty(const _Cont& __c)
+_NOEXCEPT_(noexcept(__c.empty()))
+-> decltype        (__c.empty())
+{ return            __c.empty(); }
+
+template <class _Tp, size_t _Sz>
+_LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY
+constexpr bool empty(const _Tp (&)[_Sz]) noexcept { return false; }
+
+template <class _Ep>
+_LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY
+constexpr bool empty(initializer_list<_Ep> __il) noexcept { return __il.size() == 0; }
+
+#endif // _LIBCPP_STD_VER > 14
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ITERATOR_EMPTY_H

libcxx/include/__iterator/erase_if_container.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_ERASE_IF_CONTAINER_H
+#define _LIBCPP___ITERATOR_ERASE_IF_CONTAINER_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Container, class _Predicate>
+typename _Container::size_type
+__libcpp_erase_if_container(_Container& __c, _Predicate& __pred) {
+  typename _Container::size_type __old_size = __c.size();
+
+  const typename _Container::iterator __last = __c.end();
+  for (typename _Container::iterator __iter = __c.begin(); __iter != __last;) {
+    if (__pred(*__iter))
+      __iter = __c.erase(__iter);
+    else
+      ++__iter;
+  }
+
+  return __old_size - __c.size();
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ITERATOR_ERASE_IF_CONTAINER_H

libcxx/include/__iterator/front_insert_iterator.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_FRONT_INSERT_ITERATOR_H
 #define _LIBCPP___ITERATOR_FRONT_INSERT_ITERATOR_H
 
 #include <__config>
-#include <__iterator/iterator_traits.h>
 #include <__iterator/iterator.h>
+#include <__iterator/iterator_traits.h>
 #include <__memory/addressof.h>
+#include <__utility/move.h>
 #include <cstddef>
-#include <utility> // std::move
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #pragma GCC system_header
 #endif
 
 _LIBCPP_PUSH_MACROS
 #include <__undef_macros>
 

libcxx/include/__iterator/insert_iterator.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_INSERT_ITERATOR_H
 #define _LIBCPP___ITERATOR_INSERT_ITERATOR_H
 
 #include <__config>
-#include <__iterator/iterator_traits.h>
 #include <__iterator/iterator.h>
+#include <__iterator/iterator_traits.h>
 #include <__memory/addressof.h>
+#include <__utility/move.h>
 #include <cstddef>
-#include <utility> // std::move
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #pragma GCC system_header
 #endif
 
 _LIBCPP_PUSH_MACROS
 #include <__undef_macros>
 

libcxx/include/__iterator/istream_iterator.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_ISTREAM_ITERATOR_H
 #define _LIBCPP___ITERATOR_ISTREAM_ITERATOR_H
 
 #include <__config>
-#include <__iterator/iterator_traits.h>
 #include <__iterator/iterator.h>
+#include <__iterator/iterator_traits.h>
 #include <__memory/addressof.h>
-#include <cstddef>
 #include <iosfwd> // for forward declarations of char_traits and basic_istream
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #pragma GCC system_header
 #endif
 
 _LIBCPP_PUSH_MACROS
 #include <__undef_macros>

libcxx/include/__iterator/istreambuf_iterator.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_ISTREAMBUF_ITERATOR_H
 #define _LIBCPP___ITERATOR_ISTREAMBUF_ITERATOR_H
 
 #include <__config>
-#include <__iterator/iterator_traits.h>
 #include <__iterator/iterator.h>
+#include <__iterator/iterator_traits.h>
 #include <iosfwd> // for forward declaration of basic_streambuf
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #pragma GCC system_header
 #endif
 
 _LIBCPP_PUSH_MACROS
 #include <__undef_macros>

libcxx/include/__iterator/ostream_iterator.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_OSTREAM_ITERATOR_H
 #define _LIBCPP___ITERATOR_OSTREAM_ITERATOR_H
 
 #include <__config>
-#include <__iterator/iterator_traits.h>
 #include <__iterator/iterator.h>
+#include <__iterator/iterator_traits.h>
 #include <__memory/addressof.h>
-#include <cstddef>
 #include <iosfwd> // for forward declarations of char_traits and basic_ostream
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #pragma GCC system_header
 #endif
 
 _LIBCPP_PUSH_MACROS
 #include <__undef_macros>

libcxx/include/__iterator/ostreambuf_iterator.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_OSTREAMBUF_ITERATOR_H
 #define _LIBCPP___ITERATOR_OSTREAMBUF_ITERATOR_H
 
 #include <__config>
-#include <__iterator/iterator_traits.h>
 #include <__iterator/iterator.h>
+#include <__iterator/iterator_traits.h>
 #include <iosfwd> // for forward declaration of basic_streambuf
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #pragma GCC system_header
 #endif
 
 _LIBCPP_PUSH_MACROS
 #include <__undef_macros>

libcxx/include/__iterator/reverse_access.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_REVERSE_ACCESS_H
+#define _LIBCPP___ITERATOR_REVERSE_ACCESS_H
+
+#include <__config>
+#include <__iterator/reverse_iterator.h>
+#include <cstddef>
+#include <initializer_list>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if !defined(_LIBCPP_CXX03_LANG)
+
+#if _LIBCPP_STD_VER > 11
+
+template <class _Tp, size_t _Np>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+reverse_iterator<_Tp*> rbegin(_Tp (&__array)[_Np])
+{
+    return reverse_iterator<_Tp*>(__array + _Np);
+}
+
+template <class _Tp, size_t _Np>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+reverse_iterator<_Tp*> rend(_Tp (&__array)[_Np])
+{
+    return reverse_iterator<_Tp*>(__array);
+}
+
+template <class _Ep>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+reverse_iterator<const _Ep*> rbegin(initializer_list<_Ep> __il)
+{
+    return reverse_iterator<const _Ep*>(__il.end());
+}
+
+template <class _Ep>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+reverse_iterator<const _Ep*> rend(initializer_list<_Ep> __il)
+{
+    return reverse_iterator<const _Ep*>(__il.begin());
+}
+
+template <class _Cp>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+auto rbegin(_Cp& __c) -> decltype(__c.rbegin())
+{
+    return __c.rbegin();
+}
+
+template <class _Cp>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+auto rbegin(const _Cp& __c) -> decltype(__c.rbegin())
+{
+    return __c.rbegin();
+}
+
+template <class _Cp>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+auto rend(_Cp& __c) -> decltype(__c.rend())
+{
+    return __c.rend();
+}
+
+template <class _Cp>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+auto rend(const _Cp& __c) -> decltype(__c.rend())
+{
+    return __c.rend();
+}
+
+template <class _Cp>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+auto crbegin(const _Cp& __c) -> decltype(_VSTD::rbegin(__c))
+{
+    return _VSTD::rbegin(__c);
+}
+
+template <class _Cp>
+_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
+auto crend(const _Cp& __c) -> decltype(_VSTD::rend(__c))
+{
+    return _VSTD::rend(__c);
+}
+
+#endif
+
+#endif // !defined(_LIBCPP_CXX03_LANG)
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ITERATOR_REVERSE_ACCESS_H

libcxx/include/__iterator/reverse_iterator.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_REVERSE_ITERATOR_H
 #define _LIBCPP___ITERATOR_REVERSE_ITERATOR_H
 
 #include <__config>
-#include <__iterator/iterator_traits.h>
 #include <__iterator/iterator.h>
+#include <__iterator/iterator_traits.h>
 #include <__memory/addressof.h>
 #include <type_traits>
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #pragma GCC system_header
 #endif
 
 _LIBCPP_PUSH_MACROS

libcxx/include/__iterator/size.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_SIZE_H
+#define _LIBCPP___ITERATOR_SIZE_H
+
+#include <__config>
+#include <cstddef>
+#include <type_traits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER > 14
+
+template <class _Cont>
+_LIBCPP_INLINE_VISIBILITY
+constexpr auto size(const _Cont& __c)
+_NOEXCEPT_(noexcept(__c.size()))
+-> decltype        (__c.size())
+{ return            __c.size(); }
+
+template <class _Tp, size_t _Sz>
+_LIBCPP_INLINE_VISIBILITY
+constexpr size_t size(const _Tp (&)[_Sz]) noexcept { return _Sz; }
+
+#if _LIBCPP_STD_VER > 17
+template <class _Cont>
+_LIBCPP_INLINE_VISIBILITY
+constexpr auto ssize(const _Cont& __c)
+_NOEXCEPT_(noexcept(static_cast<common_type_t<ptrdiff_t, make_signed_t<decltype(__c.size())>>>(__c.size())))
+->                              common_type_t<ptrdiff_t, make_signed_t<decltype(__c.size())>>
+{ return            static_cast<common_type_t<ptrdiff_t, make_signed_t<decltype(__c.size())>>>(__c.size()); }
+
+template <class _Tp, ptrdiff_t _Sz>
+_LIBCPP_INLINE_VISIBILITY
+constexpr ptrdiff_t ssize(const _Tp (&)[_Sz]) noexcept { return _Sz; }
+#endif
+
+#endif // _LIBCPP_STD_VER > 14
+
+_LIBCPP_END_NAMESPACE_STD
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ITERATOR_SIZE_H

libcxx/include/iterator

 
 }  // std
 
 */
 
 #include <__config>
 #include <__debug>
 #include <__functional_base>
+#include <__iterator/access.h>
 #include <__iterator/advance.h>
 #include <__iterator/back_insert_iterator.h>
 #include <__iterator/concepts.h>
+#include <__iterator/data.h>
 #include <__iterator/default_sentinel.h>
+#include <__iterator/distance.h>
+#include <__iterator/empty.h>
+#include <__iterator/erase_if_container.h>
 #include <__iterator/front_insert_iterator.h>
 #include <__iterator/incrementable_traits.h>
 #include <__iterator/insert_iterator.h>
-#include <__iterator/istream_iterator.h>
 #include <__iterator/istreambuf_iterator.h>
+#include <__iterator/istream_iterator.h>
+#include <__iterator/iterator.h>
+#include <__iterator/iterator_traits.h>
 #include <__iterator/iter_move.h>
 #include <__iterator/iter_swap.h>
-#include <__iterator/iterator_traits.h>
-#include <__iterator/iterator.h>
 #include <__iterator/move_iterator.h>
 #include <__iterator/next.h>
-#include <__iterator/ostream_iterator.h>
 #include <__iterator/ostreambuf_iterator.h>
+#include <__iterator/ostream_iterator.h>
 #include <__iterator/prev.h>
 #include <__iterator/projected.h>
 #include <__iterator/readable_traits.h>
+#include <__iterator/reverse_access.h>
 #include <__iterator/reverse_iterator.h>
+#include <__iterator/size.h>
 #include <__iterator/wrap_iter.h>
 #include <__memory/addressof.h>
 #include <__memory/pointer_traits.h>
 #include <__utility/forward.h>
 #include <compare>
 #include <concepts> // Mandated by the Standard.
 #include <cstddef>
 #include <initializer_list>
 #include <type_traits>
 #include <version>
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #pragma GCC system_header
 #endif
 
-_LIBCPP_BEGIN_NAMESPACE_STD
-
-template <class _InputIter>
-inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
-typename iterator_traits<_InputIter>::difference_type
-__distance(_InputIter __first, _InputIter __last, input_iterator_tag)
-{
-    typename iterator_traits<_InputIter>::difference_type __r(0);
-    for (; __first != __last; ++__first)
-        ++__r;
-    return __r;
-}
-
-template <class _RandIter>
-inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
-typename iterator_traits<_RandIter>::difference_type
-__distance(_RandIter __first, _RandIter __last, random_access_iterator_tag)
-{
-    return __last - __first;
-}
-
-template <class _InputIter>
-inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
-typename iterator_traits<_InputIter>::difference_type
-distance(_InputIter __first, _InputIter __last)
-{
-    return _VSTD::__distance(__first, __last, typename iterator_traits<_InputIter>::iterator_category());
-}
-
-template <class _Tp, size_t _Np>
-_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
-_Tp*
-begin(_Tp (&__array)[_Np])
-{
-    return __array;
-}
-
-template <class _Tp, size_t _Np>
-_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
-_Tp*
-end(_Tp (&__array)[_Np])
-{
-    return __array + _Np;
-}
-
-#if !defined(_LIBCPP_CXX03_LANG)
-
-template <class _Cp>
-_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
-auto
-begin(_Cp& __c) -> decltype(__c.begin())
-{
-    return __c.begin();
-}
-
-template <class _Cp>
-_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
-auto
-begin(const _Cp& __c) -> decltype(__c.begin())
-{
-    return __c.begin();
-}
-
-template <class _Cp>
-_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
-auto
-end(_Cp& __c) -> decltype(__c.end())
-{
-    return __c.end();
-}
-
-template <class _Cp>
-_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
-auto
-end(const _Cp& __c) -> decltype(__c.end())
-{
-    return __c.end();
-}
-
-#if _LIBCPP_STD_VER > 11
-
-template <class _Tp, size_t _Np>
-_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
-reverse_iterator<_Tp*> rbegin(_Tp (&__array)[_Np])
-{
-    return reverse_iterator<_Tp*>(__array + _Np);
-}
-
-template <class _Tp, size_t _Np>
-_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
-reverse_iterator<_Tp*> rend(_Tp (&__array)[_Np])
-{
-    return reverse_iterator<_Tp*>(__array);
-}
-
-template <class _Ep>
-_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
-reverse_iterator<const _Ep*> rbegin(initializer_list<_Ep> __il)
-{
-    return reverse_iterator<const _Ep*>(__il.end());
-}
-
-template <class _Ep>
-_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
-reverse_iterator<const _Ep*> rend(initializer_list<_Ep> __il)
-{
-    return reverse_iterator<const _Ep*>(__il.begin());
-}
-
-template <class _Cp>
-_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
-auto cbegin(const _Cp& __c) -> decltype(_VSTD::begin(__c))
-{
-    return _VSTD::begin(__c);
-}
-
-template <class _Cp>
-_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
-auto cend(const _Cp& __c) -> decltype(_VSTD::end(__c))
-{
-    return _VSTD::end(__c);
-}
-
-template <class _Cp>
-_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
-auto rbegin(_Cp& __c) -> decltype(__c.rbegin())
-{
-    return __c.rbegin();
-}
-
-template <class _Cp>
-_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
-auto rbegin(const _Cp& __c) -> decltype(__c.rbegin())
-{
-    return __c.rbegin();
-}
-
-template <class _Cp>
-_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
-auto rend(_Cp& __c) -> decltype(__c.rend())
-{
-    return __c.rend();
-}
-
-template <class _Cp>
-_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
-auto rend(const _Cp& __c) -> decltype(__c.rend())
-{
-    return __c.rend();
-}
-
-template <class _Cp>
-_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
-auto crbegin(const _Cp& __c) -> decltype(_VSTD::rbegin(__c))
-{
-    return _VSTD::rbegin(__c);
-}
-
-template <class _Cp>
-_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
-auto crend(const _Cp& __c) -> decltype(_VSTD::rend(__c))
-{
-    return _VSTD::rend(__c);
-}
-
-#endif
-
-
-#else  // defined(_LIBCPP_CXX03_LANG)
-
-template <class _Cp>
-_LIBCPP_INLINE_VISIBILITY
-typename _Cp::iterator
-begin(_Cp& __c)
-{
-    return __c.begin();
-}
-
-template <class _Cp>
-_LIBCPP_INLINE_VISIBILITY
-typename _Cp::const_iterator
-begin(const _Cp& __c)
-{
-    return __c.begin();
-}
-
-template <class _Cp>
-_LIBCPP_INLINE_VISIBILITY
-typename _Cp::iterator
-end(_Cp& __c)
-{
-    return __c.end();
-}
-
-template <class _Cp>
-_LIBCPP_INLINE_VISIBILITY
-typename _Cp::const_iterator
-end(const _Cp& __c)
-{
-    return __c.end();
-}
-
-#endif // !defined(_LIBCPP_CXX03_LANG)
-
-#if _LIBCPP_STD_VER > 14
-
-// #if _LIBCPP_STD_VER > 11
-// template <>
-// struct _LIBCPP_TEMPLATE_VIS plus<void>
-// {
-//     template <class _T1, class _T2>
-//     _LIBCPP_CONSTEXPR_AFTER_CXX11 _LIBCPP_INLINE_VISIBILITY
-//     auto operator()(_T1&& __t, _T2&& __u) const
-//     _NOEXCEPT_(noexcept(_VSTD::forward<_T1>(__t) + _VSTD::forward<_T2>(__u)))
-//     -> decltype        (_VSTD::forward<_T1>(__t) + _VSTD::forward<_T2>(__u))
-//         { return        _VSTD::forward<_T1>(__t) + _VSTD::forward<_T2>(__u); }
-//     typedef void is_transparent;
-// };
-// #endif
-
-template <class _Cont>
-_LIBCPP_INLINE_VISIBILITY
-constexpr auto size(const _Cont& __c)
-_NOEXCEPT_(noexcept(__c.size()))
--> decltype        (__c.size())
-{ return            __c.size(); }
-
-template <class _Tp, size_t _Sz>
-_LIBCPP_INLINE_VISIBILITY
-constexpr size_t size(const _Tp (&)[_Sz]) noexcept { return _Sz; }
-
-#if _LIBCPP_STD_VER > 17
-template <class _Cont>
-_LIBCPP_INLINE_VISIBILITY
-constexpr auto ssize(const _Cont& __c)
-_NOEXCEPT_(noexcept(static_cast<common_type_t<ptrdiff_t, make_signed_t<decltype(__c.size())>>>(__c.size())))
-->                              common_type_t<ptrdiff_t, make_signed_t<decltype(__c.size())>>
-{ return            static_cast<common_type_t<ptrdiff_t, make_signed_t<decltype(__c.size())>>>(__c.size()); }
-
-template <class _Tp, ptrdiff_t _Sz>
-_LIBCPP_INLINE_VISIBILITY
-constexpr ptrdiff_t ssize(const _Tp (&)[_Sz]) noexcept { return _Sz; }
-#endif
-
-template <class _Cont>
-_LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY
-constexpr auto empty(const _Cont& __c)
-_NOEXCEPT_(noexcept(__c.empty()))
--> decltype        (__c.empty())
-{ return            __c.empty(); }
-
-template <class _Tp, size_t _Sz>
-_LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY
-constexpr bool empty(const _Tp (&)[_Sz]) noexcept { return false; }
-
-template <class _Ep>
-_LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY
-constexpr bool empty(initializer_list<_Ep> __il) noexcept { return __il.size() == 0; }
-
-template <class _Cont> constexpr
-_LIBCPP_INLINE_VISIBILITY
-auto data(_Cont& __c)
-_NOEXCEPT_(noexcept(__c.data()))
--> decltype        (__c.data())
-{ return            __c.data(); }
-
-template <class _Cont> constexpr
-_LIBCPP_INLINE_VISIBILITY
-auto data(const _Cont& __c)
-_NOEXCEPT_(noexcept(__c.data()))
--> decltype        (__c.data())
-{ return            __c.data(); }
-
-template <class _Tp, size_t _Sz>
-_LIBCPP_INLINE_VISIBILITY
-constexpr _Tp* data(_Tp (&__array)[_Sz]) noexcept { return __array; }
-
-template <class _Ep>
-_LIBCPP_INLINE_VISIBILITY
-constexpr const _Ep* data(initializer_list<_Ep> __il) noexcept { return __il.begin(); }
-#endif
-
-template <class _Container, class _Predicate>
-typename _Container::size_type
-__libcpp_erase_if_container(_Container& __c, _Predicate& __pred) {
-  typename _Container::size_type __old_size = __c.size();
-
-  const typename _Container::iterator __last = __c.end();
-  for (typename _Container::iterator __iter = __c.begin(); __iter != __last;) {
-    if (__pred(*__iter))
-      __iter = __c.erase(__iter);
-    else
-      ++__iter;
-  }
-
-  return __old_size - __c.size();
-}
-
-_LIBCPP_END_NAMESPACE_STD
-
 #endif // _LIBCPP_ITERATOR

libcxx/include/module.modulemap

module istream {
     // FIXME: should re-export ios, streambuf?
     export *
   }
   module iterator {
     header "iterator"
     export *
 
     module __iterator {
-      module advance                { header "__iterator/advance.h"               }
-      module back_insert_iterator   { header "__iterator/back_insert_iterator.h"  }
-      module concepts               { header "__iterator/concepts.h"              }
-      module default_sentinel       { header "__iterator/default_sentinel.h"      }
-      module front_insert_iterator  { header "__iterator/front_insert_iterator.h" }
-      module incrementable_traits   { header "__iterator/incrementable_traits.h"  }
-      module insert_iterator        { header "__iterator/insert_iterator.h"       }
-      module istream_iterator       { header "__iterator/istream_iterator.h"      }
-      module istreambuf_iterator    { header "__iterator/istreambuf_iterator.h"   }
-      module iter_move              { header "__iterator/iter_move.h"             }
-      module iter_swap              { header "__iterator/iter_swap.h"             }
-      module iterator               { header "__iterator/iterator.h"              }
-      module iterator_traits        { header "__iterator/iterator_traits.h"       }
-      module move_iterator          { header "__iterator/move_iterator.h"         }
-      module next                   { header "__iterator/next.h"                  }
-      module ostream_iterator       { header "__iterator/ostream_iterator.h"      }
-      module ostreambuf_iterator    { header "__iterator/ostreambuf_iterator.h"   }
-      module prev                   { header "__iterator/prev.h"                  }
-      module projected              { header "__iterator/projected.h"             }
-      module readable_traits        { header "__iterator/readable_traits.h"       }
-      module reverse_iterator       { header "__iterator/reverse_iterator.h"      }
-      module wrap_iter              { header "__iterator/wrap_iter.h"             }
+      module access                { header "__iterator/access.h" }
+      module advance               { header "__iterator/advance.h" }
+      module back_insert_iterator  { header "__iterator/back_insert_iterator.h" }
+      module concepts              { header "__iterator/concepts.h" }
+      module data                  { header "__iterator/data.h" }
+      module default_sentinel      { header "__iterator/default_sentinel.h" }
+      module distance              { header "__iterator/distance.h" }
+      module empty                 { header "__iterator/empty.h" }
+      module erase_if_container    { header "__iterator/erase_if_container.h" }
+      module front_insert_iterator { header "__iterator/front_insert_iterator.h" }
+      module incrementable_traits  { header "__iterator/incrementable_traits.h" }
+      module insert_iterator       { header "__iterator/insert_iterator.h" }
+      module istreambuf_iterator   { header "__iterator/istreambuf_iterator.h" }
+      module istream_iterator      { header "__iterator/istream_iterator.h" }
+      module iterator              { header "__iterator/iterator.h" }
+      module iterator_traits       { header "__iterator/iterator_traits.h" }
+      module iter_move             { header "__iterator/iter_move.h" }
+      module iter_swap             { header "__iterator/iter_swap.h" }
+      module move_iterator         { header "__iterator/move_iterator.h" }
+      module next                  { header "__iterator/next.h" }
+      module ostreambuf_iterator   { header "__iterator/ostreambuf_iterator.h" }
+      module ostream_iterator      { header "__iterator/ostream_iterator.h" }
+      module prev                  { header "__iterator/prev.h" }
+      module projected             { header "__iterator/projected.h" }
+      module readable_traits       { header "__iterator/readable_traits.h" }
+      module reverse_access        { header "__iterator/reverse_access.h" }
+      module reverse_iterator      { header "__iterator/reverse_iterator.h" }
+      module size                  { header "__iterator/size.h" }
+      module wrap_iter             { header "__iterator/wrap_iter.h" }
     }
   }
   module latch {
     requires cplusplus14
     header "latch"
     export *
   }
   module limits {

libcxx/test/support/test_iterators.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 ITERATORS_H
 #define ITERATORS_H
 
 #include <iterator>
 #include <stdexcept>
 #include <cstddef>
 #include <cassert>
+#include <utility>
 
 #include "test_macros.h"
 
 #if TEST_STD_VER >= 11
 #define DELETE_FUNCTION = delete
 #else
 #define DELETE_FUNCTION
 #endif