Merge main to feature/flat_map

README.md

@@ -58,7 +58,7 @@ issue. The [bug tag][] and [enhancement tag][] are being populated.
 
 # Goals
 
-We're implementing the latest C++ Working Draft, currently [N4981][], which will eventually become the next C++
+We're implementing the latest C++ Working Draft, currently [N4988][], which will eventually become the next C++
 International Standard. The terms Working Draft (WD) and Working Paper (WP) are interchangeable; we often
 informally refer to these drafts as "the Standard" while being aware of the difference. (There are other relevant
 Standards; for example, supporting `/std:c++14` and `/std:c++17` involves understanding how the C++14 and C++17
@@ -141,11 +141,15 @@ Just try to follow these rules, so we can spend more time fixing bugs and implem
 
 # How To Build With The Visual Studio IDE
 
-1. Install Visual Studio 2022 17.11 Preview 3 or later.
+1. Install Visual Studio 2022 17.12 Preview 1 or later.
     * Select "Windows 11 SDK (10.0.22621.0)" in the VS Installer.
+    * Select "MSVC v143 - VS 2022 C++ ARM64/ARM64EC build tools (Latest)" in the VS Installer
+    if you would like to build the ARM64/ARM64EC target.
+    * Select "MSVC v143 - VS 2022 C++ ARM build tools (Latest)" in the VS Installer
+    if you would like to build the ARM target.
     * We recommend selecting "C++ CMake tools for Windows" in the VS Installer.
     This will ensure that you're using supported versions of CMake and Ninja.
-    * Otherwise, install [CMake][] 3.29.0 or later, and [Ninja][] 1.11.0 or later.
+    * Otherwise, install [CMake][] 3.29.0 or later, and [Ninja][] 1.12.1 or later.
     * Make sure [Python][] 3.12 or later is available to CMake.
 2. Open Visual Studio, and choose the "Clone or check out code" option. Enter the URL of this repository,
    `https://github.com/microsoft/STL`.
@@ -156,11 +160,15 @@ Just try to follow these rules, so we can spend more time fixing bugs and implem
 
 # How To Build With A Native Tools Command Prompt
 
-1. Install Visual Studio 2022 17.11 Preview 3 or later.
+1. Install Visual Studio 2022 17.12 Preview 1 or later.
     * Select "Windows 11 SDK (10.0.22621.0)" in the VS Installer.
+    * Select "MSVC v143 - VS 2022 C++ ARM64/ARM64EC build tools (Latest)" in the VS Installer
+    if you would like to build the ARM64/ARM64EC target.
+    * Select "MSVC v143 - VS 2022 C++ ARM build tools (Latest)" in the VS Installer
+    if you would like to build the ARM target.
     * We recommend selecting "C++ CMake tools for Windows" in the VS Installer.
     This will ensure that you're using supported versions of CMake and Ninja.
-    * Otherwise, install [CMake][] 3.29.0 or later, and [Ninja][] 1.11.0 or later.
+    * Otherwise, install [CMake][] 3.29.0 or later, and [Ninja][] 1.12.1 or later.
     * Make sure [Python][] 3.12 or later is available to CMake.
 2. Open a command prompt.
 3. Change directories to a location where you'd like a clone of this STL repository.
@@ -180,6 +188,30 @@ To build the x64 target (recommended):
 3. `cmake --preset x64`
 4. `cmake --build --preset x64`
 
+To build the ARM target:
+
+1. `"C:\Program Files\Microsoft Visual Studio\2022\Preview\VC\Auxiliary\Build\vcvarsall.bat" x64_arm`
+    * If you installed VS to a non-default location, change this path accordingly.
+2. Change directories to the previously cloned `STL` directory.
+3. `cmake --preset ARM`
+4. `cmake --build --preset ARM`
+
+To build the ARM64 target:
+
+1. `"C:\Program Files\Microsoft Visual Studio\2022\Preview\VC\Auxiliary\Build\vcvarsall.bat" x64_arm64`
+    * If you installed VS to a non-default location, change this path accordingly.
+2. Change directories to the previously cloned `STL` directory.
+3. `cmake --preset ARM64`
+4. `cmake --build --preset ARM64`
+
+To build the ARM64EC target:
+
+1. `"C:\Program Files\Microsoft Visual Studio\2022\Preview\VC\Auxiliary\Build\vcvarsall.bat" x64_arm64`
+    * If you installed VS to a non-default location, change this path accordingly.
+2. Change directories to the previously cloned `STL` directory.
+3. `cmake --preset ARM64EC`
+4. `cmake --build --preset ARM64EC`
+
 # How To Consume
 
 Consumption of the built library is largely based on the build system you're using. There are at least 2 directories
@@ -537,7 +569,7 @@ SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 [LWG issues]: https://cplusplus.github.io/LWG/lwg-toc.html
 [LWG tag]: https://github.com/microsoft/STL/issues?q=is%3Aopen+is%3Aissue+label%3ALWG
 [Microsoft Open Source Code of Conduct]: https://opensource.microsoft.com/codeofconduct/
-[N4981]: https://wg21.link/N4981
+[N4988]: https://wg21.link/N4988
 [NOTICE.txt]: NOTICE.txt
 [Ninja]: https://ninja-build.org
 [STL-CI-badge]: https://dev.azure.com/vclibs/STL/_apis/build/status%2FSTL-CI?branchName=main "STL-CI"

azure-devops/config.yml

@@ -5,7 +5,7 @@
 
 variables:
 - name: poolName
-  value: 'StlBuild-2024-07-09T1614-Pool'
+  value: 'StlBuild-2024-08-14T0018-Pool'
   readonly: true
 - name: poolDemands
   value: 'EnableSpotVM -equals false'

azure-devops/provision-image.ps1

@@ -40,10 +40,10 @@ foreach ($workload in $VisualStudioWorkloads) {
 }
 
 # https://github.com/PowerShell/PowerShell/releases/latest
-$PowerShellUrl = 'https://github.com/PowerShell/PowerShell/releases/download/v7.4.3/PowerShell-7.4.3-win-x64.msi'
+$PowerShellUrl = 'https://github.com/PowerShell/PowerShell/releases/download/v7.4.4/PowerShell-7.4.4-win-x64.msi'
 $PowerShellArgs = @('/quiet', '/norestart')
 
-$PythonUrl = 'https://www.python.org/ftp/python/3.12.4/python-3.12.4-amd64.exe'
+$PythonUrl = 'https://www.python.org/ftp/python/3.12.5/python-3.12.5-amd64.exe'
 $PythonArgs = @('/quiet', 'InstallAllUsers=1', 'PrependPath=1', 'CompileAll=1', 'Include_doc=0')
 
 $CudaUrl = 'https://developer.download.nvidia.com/compute/cuda/12.4.0/local_installers/cuda_12.4.0_551.61_windows.exe'

benchmarks/CMakeLists.txt

@@ -62,7 +62,7 @@ endif()
 set(CMAKE_BUILD_TYPE RelWithDebInfo)
 
 # /utf-8 affects <format>.
-add_compile_options("$<$<COMPILE_LANGUAGE:CXX>:/diagnostics:caret;/W4;/WX;/w14265;/w15038;/w15262;/utf-8>")
+add_compile_options("$<$<COMPILE_LANGUAGE:CXX>:/diagnostics:caret;/W4;/WX;/w14265;/w15038;/w15262;/utf-8;/Zc:preprocessor>")
 
 if(NOT EXISTS "${CMAKE_CURRENT_LIST_DIR}/google-benchmark/.git")
     message(FATAL_ERROR "google-benchmark is not checked out; make sure to run\n    git submodule update --init benchmarks/google-benchmark")

stl/CMakeLists.txt

@@ -422,7 +422,7 @@ add_compile_definitions(_CRTBLD _VCRT_ALLOW_INTERNALS _HAS_OLD_IOSTREAMS_MEMBERS
 set(CMAKE_MSVC_DEBUG_INFORMATION_FORMAT "Embedded")
 
 add_compile_options(/WX /Gy
-    "$<$<COMPILE_LANGUAGE:CXX>:/diagnostics:caret;/W4;/w14265;/w15038;/fastfail;/guard:cf;/Zp8;/std:c++latest;/permissive-;/Zc:threadSafeInit-;/Zl>"
+    "$<$<COMPILE_LANGUAGE:CXX>:/diagnostics:caret;/W4;/w14265;/w15038;/fastfail;/guard:cf;/Zp8;/std:c++latest;/permissive-;/Zc:preprocessor;/Zc:threadSafeInit-;/Zl>"
     "$<$<COMPILE_LANGUAGE:ASM_MASM>:/W3;/nologo;/quiet>"
 )
 
@@ -557,7 +557,7 @@ function(add_stl_dlls D_SUFFIX REL_OR_DBG)
     generate_satellite_def("atomic_wait" "${D_SUFFIX}")
 
     add_library(msvcp${D_SUFFIX}_atomic_wait SHARED "${CMAKE_BINARY_DIR}/msvcp_atomic_wait${D_SUFFIX}.def")
-    target_link_libraries(msvcp${D_SUFFIX}_atomic_wait PRIVATE msvcp${D_SUFFIX}_atomic_wait_objects msvcp${D_SUFFIX}_satellite_objects msvcp${D_SUFFIX}_implib_objects "msvcp${D_SUFFIX}" "${TOOLSET_LIB}/vcruntime${D_SUFFIX}.lib" "${TOOLSET_LIB}/msvcrt${D_SUFFIX}.lib" "ucrt${D_SUFFIX}.lib" "advapi32.lib" "synchronization.lib")
+    target_link_libraries(msvcp${D_SUFFIX}_atomic_wait PRIVATE msvcp${D_SUFFIX}_atomic_wait_objects msvcp${D_SUFFIX}_satellite_objects msvcp${D_SUFFIX}_implib_objects "msvcp${D_SUFFIX}" "${TOOLSET_LIB}/vcruntime${D_SUFFIX}.lib" "${TOOLSET_LIB}/msvcrt${D_SUFFIX}.lib" "ucrt${D_SUFFIX}.lib" "advapi32.lib")
     set_target_properties(msvcp${D_SUFFIX}_atomic_wait PROPERTIES ARCHIVE_OUTPUT_NAME "msvcp140_atomic_wait${D_SUFFIX}${VCLIBS_SUFFIX}")
     set_target_properties(msvcp${D_SUFFIX}_atomic_wait PROPERTIES ARCHIVE_OUTPUT_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}")
     set_target_properties(msvcp${D_SUFFIX}_atomic_wait PROPERTIES OUTPUT_NAME "msvcp140${D_SUFFIX}_atomic_wait${VCLIBS_SUFFIX}")

stl/debugger/STL.natvis

@@ -1520,9 +1520,9 @@ SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 
 
   <Type Name="std::move_iterator&lt;*&gt;">
-      <DisplayString>move_iterator {current}</DisplayString>
+      <DisplayString>move_iterator {_Current}</DisplayString>
       <Expand>
-          <Item Name="current">current</Item>
+          <Item Name="[current]">_Current</Item>
       </Expand>
   </Type>
 
@@ -2001,16 +2001,6 @@ SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
     </Expand>
   </Type>
 
-  <Type Name="std::ranges::view_interface&lt;*&gt;">
-    <DisplayString>{{ size={size()} }}</DisplayString>
-    <Expand>
-      <Item Optional="true" Name="empty">empty()</Item>
-      <Item Optional="true" Name="front">front()</Item>
-      <Item Optional="true" Name="back">back()</Item>
-      <Item Optional="true" Name="data">data()</Item>
-    </Expand>
-  </Type>
-
   <Type Name="std::ranges::dangling">
     <DisplayString>dangling</DisplayString>
   </Type>

stl/inc/__msvc_string_view.hpp

@@ -220,42 +220,48 @@ struct _WChar_traits : private _Char_traits<_Elem, unsigned short> {
         _In_reads_(_Count) const _Elem* const _First2, const size_t _Count) noexcept /* strengthened */ {
         // compare [_First1, _First1 + _Count) with [_First2, ...)
 #if _HAS_CXX17
-        if constexpr (is_same_v<_Elem, wchar_t>) {
-            return __builtin_wmemcmp(_First1, _First2, _Count);
-        } else {
-            return _Primary_char_traits::compare(_First1, _First2, _Count);
+        if (_STD _Is_constant_evaluated()) {
+            if constexpr (is_same_v<_Elem, wchar_t>) {
+                return __builtin_wmemcmp(_First1, _First2, _Count);
+            } else {
+                return _Primary_char_traits::compare(_First1, _First2, _Count);
+            }
         }
-#else // ^^^ _HAS_CXX17 / !_HAS_CXX17 vvv
+#endif // _HAS_CXX17
+
         return _CSTD wmemcmp(
             reinterpret_cast<const wchar_t*>(_First1), reinterpret_cast<const wchar_t*>(_First2), _Count);
-#endif // ^^^ !_HAS_CXX17 ^^^
     }
 
     _NODISCARD static _CONSTEXPR17 size_t length(_In_z_ const _Elem* _First) noexcept /* strengthened */ {
         // find length of null-terminated sequence
 #if _HAS_CXX17
-        if constexpr (is_same_v<_Elem, wchar_t>) {
-            return __builtin_wcslen(_First);
-        } else {
-            return _Primary_char_traits::length(_First);
+        if (_STD _Is_constant_evaluated()) {
+            if constexpr (is_same_v<_Elem, wchar_t>) {
+                return __builtin_wcslen(_First);
+            } else {
+                return _Primary_char_traits::length(_First);
+            }
         }
-#else // ^^^ _HAS_CXX17 / !_HAS_CXX17 vvv
+#endif // _HAS_CXX17
+
         return _CSTD wcslen(reinterpret_cast<const wchar_t*>(_First));
-#endif // ^^^ !_HAS_CXX17 ^^^
     }
 
     _NODISCARD static _CONSTEXPR17 const _Elem* find(
         _In_reads_(_Count) const _Elem* _First, const size_t _Count, const _Elem& _Ch) noexcept /* strengthened */ {
         // look for _Ch in [_First, _First + _Count)
 #if _HAS_CXX17
-        if constexpr (is_same_v<_Elem, wchar_t>) {
-            return __builtin_wmemchr(_First, _Ch, _Count);
-        } else {
-            return _Primary_char_traits::find(_First, _Count, _Ch);
+        if (_STD _Is_constant_evaluated()) {
+            if constexpr (is_same_v<_Elem, wchar_t>) {
+                return __builtin_wmemchr(_First, _Ch, _Count);
+            } else {
+                return _Primary_char_traits::find(_First, _Count, _Ch);
+            }
         }
-#else // ^^^ _HAS_CXX17 / !_HAS_CXX17 vvv
+#endif // _HAS_CXX17
+
         return reinterpret_cast<const _Elem*>(_CSTD wmemchr(reinterpret_cast<const wchar_t*>(_First), _Ch, _Count));
-#endif // ^^^ !_HAS_CXX17 ^^^
     }
 
     static _CONSTEXPR20 _Elem* assign(

stl/inc/algorithm

@@ -933,10 +933,8 @@ namespace ranges {
         _NODISCARD _STATIC_CALL_OPERATOR constexpr bool operator()(
             _Rng1&& _Range1, _Rng2&& _Range2, _Pr _Pred = {}, _Pj1 _Proj1 = {}, _Pj2 _Proj2 = {}) _CONST_CALL_OPERATOR {
             if constexpr (sized_range<_Rng1> && sized_range<_Rng2>) {
-                using _Size1      = _Make_unsigned_like_t<range_size_t<_Rng1>>;
-                const auto _Count = static_cast<_Size1>(_RANGES size(_Range1));
-                using _Size2      = _Make_unsigned_like_t<range_size_t<_Rng2>>;
-                if (_Count != static_cast<_Size2>(_RANGES size(_Range2))) {
+                const auto _Count = _RANGES distance(_Range1);
+                if (_Count != _RANGES distance(_Range2)) {
                     return false;
                 }
                 return _RANGES _Equal_count(_Ubegin(_Range1), _Ubegin(_Range2), _Count, _STD _Pass_fn(_Pred),
@@ -7781,7 +7779,7 @@ namespace ranges {
     void _Rotate_one_right(_It _First, _It _Mid, _It _Last) {
         // exchanges the range [_First, _Mid) with [_Mid, _Last)
         _STL_INTERNAL_CHECK(_RANGES next(_Mid) == _Last);
-        auto _Temp = _RANGES iter_move(_Mid);
+        iter_value_t<_It> _Temp(_RANGES iter_move(_Mid));
         _RANGES _Move_backward_common(_First, _STD move(_Mid), _STD move(_Last));
         *_First = _STD move(_Temp);
     }
@@ -7790,7 +7788,7 @@ namespace ranges {
     void _Rotate_one_left(_It _First, _It _Mid, _It _Last) {
         // exchanges the range [_First, _Mid) with [_Mid, _Last)
         _STL_INTERNAL_CHECK(_RANGES next(_First) == _Mid);
-        auto _Temp   = _RANGES iter_move(_First);
+        iter_value_t<_It> _Temp(_RANGES iter_move(_First));
         auto _Result = _RANGES _Move_unchecked(_STD move(_Mid), _STD move(_Last), _STD move(_First));
         *_Result.out = _STD move(_Temp);
     }
@@ -10286,7 +10284,7 @@ namespace ranges {
                 }
 
                 while (++_UFirst != _ULast) { // process one or two elements
-                    auto _Prev = *_UFirst;
+                    _Vty _Prev(*_UFirst);
                     if (++_UFirst == _ULast) { // process last element
                         if (_STD invoke(_Pred, _STD invoke(_Proj, _Prev), _STD invoke(_Proj, _Found.min))) {
                             _Found.min = _STD move(_Prev);
@@ -10723,7 +10721,8 @@ namespace ranges {
 #endif // _HAS_CXX20
 
 _EXPORT_STD template <class _Ty, class _Pr>
-_NODISCARD constexpr const _Ty& clamp(const _Ty& _Val, const _Ty& _Min_val, const _Ty& _Max_val, _Pr _Pred) {
+_NODISCARD constexpr const _Ty& clamp(const _Ty& _Val _MSVC_LIFETIMEBOUND, const _Ty& _Min_val _MSVC_LIFETIMEBOUND,
+    const _Ty& _Max_val _MSVC_LIFETIMEBOUND, _Pr _Pred) {
     // returns _Val constrained to [_Min_val, _Max_val]
 #if _ITERATOR_DEBUG_LEVEL == 2
     if (_DEBUG_LT_PRED(_Pred, _Max_val, _Min_val)) {
@@ -10750,7 +10749,8 @@ _NODISCARD constexpr const _Ty& clamp(const _Ty& _Val, const _Ty& _Min_val, cons
 }
 
 _EXPORT_STD template <class _Ty>
-_NODISCARD constexpr const _Ty& clamp(const _Ty& _Val, const _Ty& _Min_val, const _Ty& _Max_val) {
+_NODISCARD constexpr const _Ty& clamp(const _Ty& _Val _MSVC_LIFETIMEBOUND, const _Ty& _Min_val _MSVC_LIFETIMEBOUND,
+    const _Ty& _Max_val _MSVC_LIFETIMEBOUND) {
     // returns _Val constrained to [_Min_val, _Max_val]
     return _STD clamp(_Val, _Min_val, _Max_val, less{});
 }
@@ -10761,8 +10761,9 @@ namespace ranges {
     public:
         template <class _Ty, class _Pj = identity,
             indirect_strict_weak_order<projected<const _Ty*, _Pj>> _Pr = ranges::less>
-        _NODISCARD _STATIC_CALL_OPERATOR constexpr const _Ty& operator()(
-            const _Ty& _Val, const _Ty& _Lo, const _Ty& _Hi, _Pr _Pred = {}, _Pj _Proj = {}) _CONST_CALL_OPERATOR {
+        _NODISCARD _STATIC_CALL_OPERATOR constexpr const _Ty& operator()(const _Ty& _Val _MSVC_LIFETIMEBOUND,
+            const _Ty& _Lo _MSVC_LIFETIMEBOUND, const _Ty& _Hi _MSVC_LIFETIMEBOUND, _Pr _Pred = {},
+            _Pj _Proj = {}) _CONST_CALL_OPERATOR {
             _STL_ASSERT(!_STD invoke(_Pred, _STD invoke(_Proj, _Hi), _STD invoke(_Proj, _Lo)),
                 "The lower bound cannot be greater than the upper bound in a call to std::ranges::clamp "
                 "(N4950 [alg.clamp]/2).");

stl/inc/array

@@ -500,7 +500,7 @@ public:
         return _Elems + _Size;
     }
 
-    _NODISCARD constexpr size_type size() const noexcept {
+    _NODISCARD _Ret_range_(==, _Size) constexpr size_type size() const noexcept {
         return _Size;
     }
 
@@ -528,15 +528,15 @@ public:
         return _Elems[_Pos];
     }
 
-    _NODISCARD _CONSTEXPR17 reference operator[](_In_range_(0, _Size - 1) size_type _Pos) noexcept /* strengthened */ {
+    _NODISCARD _CONSTEXPR17 reference operator[](_In_range_(<, _Size) size_type _Pos) noexcept /* strengthened */ {
 #if _CONTAINER_DEBUG_LEVEL > 0
         _STL_VERIFY(_Pos < _Size, "array subscript out of range");
 #endif // _CONTAINER_DEBUG_LEVEL > 0
 
         return _Elems[_Pos];
     }
 
-    _NODISCARD constexpr const_reference operator[](_In_range_(0, _Size - 1) size_type _Pos) const noexcept
+    _NODISCARD constexpr const_reference operator[](_In_range_(<, _Size) size_type _Pos) const noexcept
     /* strengthened */ {
 #if _CONTAINER_DEBUG_LEVEL > 0
         _STL_VERIFY(_Pos < _Size, "array subscript out of range");