More -Wconversion fixes

.drone.jsonnet

@@ -344,27 +344,39 @@ local windows_pipeline(name, image, environment, arch = "amd64") =
         { TOOLSET: 'clang', COMPILER: 'clang++', CXXSTD: '03,11,14,1z' } + asan,
     ),
 
+    macos_pipeline(
+        "MacOS 12.4 Xcode 13.4.1 UBSAN",
+        { TOOLSET: 'clang', COMPILER: 'clang++', CXXSTD: '03,11,14,17,20,2b' } + ubsan,
+        xcode_version = "13.4.1", osx_version = "monterey", arch = "arm64",
+    ),
+
+    macos_pipeline(
+        "MacOS 12.4 Xcode 13.4.1 ASAN",
+        { TOOLSET: 'clang', COMPILER: 'clang++', CXXSTD: '03,11,14,17,20,2b' } + asan,
+        xcode_version = "13.4.1", osx_version = "monterey", arch = "arm64",
+    ),
+
     windows_pipeline(
         "Windows VS2015 msvc-14.0",
         "cppalliance/dronevs2015",
-        { TOOLSET: 'msvc-14.0', CXXSTD: '14,latest' },
+        { TOOLSET: 'msvc-14.0', CXXSTD: '14,latest', ADDRMD: '32,64' },
     ),
 
     windows_pipeline(
         "Windows VS2017 msvc-14.1",
         "cppalliance/dronevs2017",
-        { TOOLSET: 'msvc-14.1', CXXSTD: '14,17,latest' },
+        { TOOLSET: 'msvc-14.1', CXXSTD: '14,17,latest', ADDRMD: '32,64' },
     ),
 
     windows_pipeline(
         "Windows VS2019 msvc-14.2",
         "cppalliance/dronevs2019",
-        { TOOLSET: 'msvc-14.2', CXXSTD: '14,17,20,latest' },
+        { TOOLSET: 'msvc-14.2', CXXSTD: '14,17,20,latest', ADDRMD: '32,64' },
     ),
 
     windows_pipeline(
         "Windows VS2022 msvc-14.3",
         "cppalliance/dronevs2022:1",
-        { TOOLSET: 'msvc-14.3', CXXSTD: '14,17,20,latest' },
+        { TOOLSET: 'msvc-14.3', CXXSTD: '14,17,20,latest', ADDRMD: '32,64' },
     ),
 ]

.drone/drone.sh

@@ -5,6 +5,7 @@
 # https://www.boost.org/LICENSE_1_0.txt
 
 set -ex
+export PATH=~/.local/bin:/usr/local/bin:$PATH
 
 DRONE_BUILD_DIR=$(pwd)
 

.github/workflows/ci.yml

@@ -466,7 +466,7 @@ jobs:
             if [ -n "${{matrix.ubsan}}" ]
             then
                 export UBSAN_OPTIONS="print_stacktrace=1"
-                B2_ARGS+=("cxxflags=-fsanitize=undefined -fno-sanitize-recover=undefined" "linkflags=-fsanitize=undefined -fuse-ld=gold" "define=UBSAN=1" "debug-symbols=on" "visibility=global")
+                B2_ARGS+=("undefined-sanitizer=norecover" "linkflags=-fuse-ld=gold" "define=UBSAN=1" "debug-symbols=on" "visibility=global")
             fi
             if [ -n "${{matrix.cxxflags}}" ]
             then
@@ -700,3 +700,183 @@ jobs:
         run: |
           cd ../boost-root/__build__
           ctest --output-on-failure --no-tests=error
+
+  windows-cmake-subdir:
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - os: windows-2019
+          - os: windows-2022
+
+    runs-on: ${{matrix.os}}
+
+    steps:
+      - uses: actions/checkout@v3
+
+      - name: Setup Boost
+        shell: cmd
+        run: |
+          echo GITHUB_REPOSITORY: %GITHUB_REPOSITORY%
+          for /f %%i in ("%GITHUB_REPOSITORY%") do set LIBRARY=%%~nxi
+          echo LIBRARY: %LIBRARY%
+          echo LIBRARY=%LIBRARY%>>%GITHUB_ENV%
+          echo GITHUB_BASE_REF: %GITHUB_BASE_REF%
+          echo GITHUB_REF: %GITHUB_REF%
+          if "%GITHUB_BASE_REF%" == "" set GITHUB_BASE_REF=%GITHUB_REF%
+          set BOOST_BRANCH=develop
+          for /f %%i in ("%GITHUB_BASE_REF%") do if "%%~nxi" == "master" set BOOST_BRANCH=master
+          echo BOOST_BRANCH: %BOOST_BRANCH%
+          cd ..
+          git clone -b %BOOST_BRANCH% --depth 1 https://github.com/boostorg/boost.git boost-root
+          cd boost-root
+          xcopy /s /e /q %GITHUB_WORKSPACE% libs\%LIBRARY%\
+          git submodule update --init tools/boostdep
+          python tools/boostdep/depinst/depinst.py --git_args "--jobs 3" %LIBRARY%
+
+      - name: Use library with add_subdirectory (Debug)
+        shell: cmd
+        run: |
+          cd ../boost-root/libs/%LIBRARY%/test/cmake_subdir_test
+          mkdir __build__ && cd __build__
+          cmake ..
+          cmake --build . --config Debug
+          ctest --output-on-failure --no-tests=error -C Debug
+
+      - name: Use library with add_subdirectory (Release)
+        shell: cmd
+        run: |
+          cd ../boost-root/libs/%LIBRARY%/test/cmake_subdir_test/__build__
+          cmake --build . --config Release
+          ctest --output-on-failure --no-tests=error -C Release
+
+  windows-cmake-install:
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - os: windows-2019
+          - os: windows-2022
+
+    runs-on: ${{matrix.os}}
+
+    steps:
+      - uses: actions/checkout@v3
+
+      - name: Setup Boost
+        shell: cmd
+        run: |
+          echo GITHUB_REPOSITORY: %GITHUB_REPOSITORY%
+          for /f %%i in ("%GITHUB_REPOSITORY%") do set LIBRARY=%%~nxi
+          echo LIBRARY: %LIBRARY%
+          echo LIBRARY=%LIBRARY%>>%GITHUB_ENV%
+          echo GITHUB_BASE_REF: %GITHUB_BASE_REF%
+          echo GITHUB_REF: %GITHUB_REF%
+          if "%GITHUB_BASE_REF%" == "" set GITHUB_BASE_REF=%GITHUB_REF%
+          set BOOST_BRANCH=develop
+          for /f %%i in ("%GITHUB_BASE_REF%") do if "%%~nxi" == "master" set BOOST_BRANCH=master
+          echo BOOST_BRANCH: %BOOST_BRANCH%
+          cd ..
+          git clone -b %BOOST_BRANCH% --depth 1 https://github.com/boostorg/boost.git boost-root
+          cd boost-root
+          xcopy /s /e /q %GITHUB_WORKSPACE% libs\%LIBRARY%\
+          git submodule update --init tools/boostdep
+          python tools/boostdep/depinst/depinst.py --git_args "--jobs 3" %LIBRARY%
+
+      - name: Configure
+        shell: cmd
+        run: |
+          cd ../boost-root
+          mkdir __build__ && cd __build__
+          cmake -DBOOST_INCLUDE_LIBRARIES=%LIBRARY% -DCMAKE_INSTALL_PREFIX=C:/cmake-prefix ..
+
+      - name: Install (Debug)
+        shell: cmd
+        run: |
+          cd ../boost-root/__build__
+          cmake --build . --target install --config Debug
+
+      - name: Install (Release)
+        shell: cmd
+        run: |
+          cd ../boost-root/__build__
+          cmake --build . --target install --config Release
+
+      - name: Use the installed library (Debug)
+        shell: cmd
+        run: |
+          cd ../boost-root/libs/%LIBRARY%/test/cmake_install_test && mkdir __build__ && cd __build__
+          cmake -DCMAKE_INSTALL_PREFIX=C:/cmake-prefix ..
+          cmake --build . --config Debug
+          ctest --output-on-failure --no-tests=error -C Debug
+
+      - name: Use the installed library (Release)
+        shell: cmd
+        run: |
+          cd ../boost-root/libs/%LIBRARY%/test/cmake_install_test/__build__
+          cmake --build . --config Release
+          ctest --output-on-failure --no-tests=error -C Release
+
+  windows-cmake-test:
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - os: windows-2019
+          - os: windows-2022
+
+    runs-on: ${{matrix.os}}
+
+    steps:
+      - uses: actions/checkout@v3
+
+      - name: Setup Boost
+        shell: cmd
+        run: |
+          echo GITHUB_REPOSITORY: %GITHUB_REPOSITORY%
+          for /f %%i in ("%GITHUB_REPOSITORY%") do set LIBRARY=%%~nxi
+          echo LIBRARY: %LIBRARY%
+          echo LIBRARY=%LIBRARY%>>%GITHUB_ENV%
+          echo GITHUB_BASE_REF: %GITHUB_BASE_REF%
+          echo GITHUB_REF: %GITHUB_REF%
+          if "%GITHUB_BASE_REF%" == "" set GITHUB_BASE_REF=%GITHUB_REF%
+          set BOOST_BRANCH=develop
+          for /f %%i in ("%GITHUB_BASE_REF%") do if "%%~nxi" == "master" set BOOST_BRANCH=master
+          echo BOOST_BRANCH: %BOOST_BRANCH%
+          cd ..
+          git clone -b %BOOST_BRANCH% --depth 1 https://github.com/boostorg/boost.git boost-root
+          cd boost-root
+          xcopy /s /e /q %GITHUB_WORKSPACE% libs\%LIBRARY%\
+          git submodule update --init tools/boostdep
+          python tools/boostdep/depinst/depinst.py --git_args "--jobs 3" %LIBRARY%
+
+      - name: Configure
+        shell: cmd
+        run: |
+          cd ../boost-root
+          mkdir __build__ && cd __build__
+          cmake -DBOOST_INCLUDE_LIBRARIES=%LIBRARY% -DBUILD_TESTING=ON ..
+
+      - name: Build tests (Debug)
+        shell: cmd
+        run: |
+          cd ../boost-root/__build__
+          cmake --build . --target tests --config Debug
+
+      - name: Run tests (Debug)
+        shell: cmd
+        run: |
+          cd ../boost-root/__build__
+          ctest --output-on-failure --no-tests=error -C Debug
+
+      - name: Build tests (Release)
+        shell: cmd
+        run: |
+          cd ../boost-root/__build__
+          cmake --build . --target tests --config Release
+
+      - name: Run tests (Release)
+        shell: cmd
+        run: |
+          cd ../boost-root/__build__
+          ctest --output-on-failure --no-tests=error -C Release

doc/bit.qbk

@@ -33,6 +33,11 @@ namespace core
 template<class To, class From>
 To bit_cast(From const& from) noexcept;
 
+// byteswap
+
+template<class T>
+constexpr T byteswap(T x) noexcept;
+
 // Integral powers of 2
 
 template<class T>
@@ -102,6 +107,17 @@ constant expression context.
 
 [endsect]
 
+[section byteswap]
+
+`template<class T> constexpr T byteswap(T x) noexcept;`
+
+* *Requires:* `T` must be an integer type (i.e. one of `char`, `signed char`,
+  `unsigned char`, `short`, `unsigned short`, `int`, `unsigned int`, `long`,
+  `unsigned long`, `long long`, `unsigned long long`) without padding bits.
+* *Returns:* `x` with the storage bytes reversed.
+
+[endsect]
+
 [section Integral powers of 2]
 
 `template<class T> constexpr bool has_single_bit(T x) noexcept;`

doc/changes.qbk

@@ -7,6 +7,16 @@
 
 [section Revision History]
 
+[section Changes in 1.83.0]
+
+* Added support for incomplete types to [link core.type_name `boost::core::type_name`].
+* Bit manipulation functions in [link core.bit `boost/core/bit.hpp`] are now
+  `constexpr` on recent MSVC versions (VS2019 update 5 and later.)
+* Added `boost::core::byteswap` (an implementation of `std::byteswap` from
+  C++23) to [link core.bit `boost/core/bit.hpp`].
+
+[endsect]
+
 [section Changes in 1.82.0]
 
 * Added [link core.snprintf `boost/core/snprintf.hpp`] header with portable definitions of `snprintf`, `vsnprintf` and
@@ -22,6 +32,15 @@
   `boost::core::max_align`, the alignment of `max_align_t`.
 * Added [link core.memory_resource `boost::core::memory_resource`], a portable equivalent of `std::pmr::memory_resource`
   from C++17.
+* Added [link core.serialization `boost/core/serialization.hpp`], a collection of primitives allowing libraries to
+  implement Boost.Serialization support for their types without including a Serialization header and thereby making
+  their libraries depend on Serialization.
+* Added [link core.data `boost::data`], an implementation of `std::data`.
+* Added [link core.size `boost::size`], an implementation of `std::size`.
+* Updated `boost::span` to use `boost::data` which adds support for range
+  construction from an `std::initializer_list`.
+* Added [link core.identity `boost::identity`], an implementation of
+  `std::identity`. This facility has been moved from Boost.Functional.
 
 [endsect]
 

doc/core.qbk

@@ -55,6 +55,7 @@ criteria for inclusion is that the utility component be:
 [include exchange.qbk]
 [include explicit_operator_bool.qbk]
 [include first_scalar.qbk]
+[include identity.qbk]
 [include ignore_unused.qbk]
 [include is_same.qbk]
 [include launder.qbk]
@@ -72,6 +73,7 @@ criteria for inclusion is that the utility component be:
 [include quick_exit.qbk]
 [include ref.qbk]
 [include scoped_enum.qbk]
+[include serialization.qbk]
 [include size.qbk]
 [include span.qbk]
 [include swap.qbk]

doc/data.qbk

@@ -50,10 +50,10 @@ data(std::initializer_list<T> l) noexcept;
 [variablelist
 [[`template<class C> constexpr auto data(C& c) noexcept(noexcept(c.data())) ->
 decltype(c.data());`]
-[Returns `c.begin()`.]]
+[Returns `c.data()`.]]
 [[`template<class C> constexpr auto data(const C& c)
 noexcept(noexcept(c.data())) -> decltype(c.data());`]
-[Returns `c.begin()`.]]
+[Returns `c.data()`.]]
 [[`template<class T, std::size_t N> constexpr T* data(T(&a)[N]) noexcept;`]
 [Returns `a`.]]
 [[`template<class T> constexpr const T* data(std::initializer_list<T> l)

doc/identity.qbk

@@ -0,0 +1,61 @@
+[/
+Copyright 2021-2023 Glen Joseph Fernandes
+(glenjofe@gmail.com)
+
+Distributed under the Boost Software License, Version 1.0.
+(http://www.boost.org/LICENSE_1_0.txt)
+]
+
+[section:identity identity]
+
+[simplesect Authors]
+
+* Glen Fernandes
+
+[endsimplesect]
+
+[section Overview]
+
+The header <boost/functional/identity.hpp> provides the function object
+`boost::identity` whose `operator()` returns its argument. It is an
+implementation of C++20's `std::identity` that supports C++03 and above.
+
+[endsect]
+
+[section Example]
+
+It is commonly used as the default projection in constrained algorithms.
+
+```
+template<class Range, class Projection = boost::identity>
+void print(Range&& range, Projection projection = {});
+```
+
+[endsect]
+
+[section Reference]
+
+```
+namespace boost {
+
+struct identity {
+    using is_transparent = unspecified;
+
+    template<class T>
+    T&& operator()(T&& value) const noexcept;
+};
+
+} /* boost */
+```
+
+[section Operators]
+
+[variablelist
+[[`template<class T> T&& operator()(T&& value) const noexcept;`]
+[Returns `std::forward<T>(value)`.]]]
+
+[endsect]
+
+[endsect]
+
+[endsect]

doc/serialization.qbk

@@ -0,0 +1,145 @@
+[/
+  Copyright 2023 Peter Dimov
+  Distributed under the Boost Software License, Version 1.0.
+  https://boost.org/LICENSE_1_0.txt
+]
+
+[section:serialization serialization]
+
+[simplesect Authors]
+
+* Peter Dimov
+
+[endsimplesect]
+
+[section Header <boost/core/serialization.hpp>]
+
+The header `<boost/core/serialization.hpp>` implements primitives
+that are necessary to implement Boost.Serialization support without
+including a Boost.Serialization header and thereby making a library
+dependent on Boost.Serialization.
+
+[section Synopsis]
+
+``
+#include <boost/core/nvp.hpp>
+
+namespace boost
+{
+namespace serialization
+{
+
+// forward declarations
+
+template<class T> struct version;
+class access;
+
+// core_version_type
+
+struct core_version_type;
+
+} // namespace serialization
+
+namespace core
+{
+
+// nvp
+
+using serialization::nvp;
+using serialization::make_nvp;
+
+// split_free
+
+template<class Ar, class T> void split_free( Ar& ar, T& t, unsigned int v );
+
+// split_member
+
+template<class Ar, class T> void split_member( Ar& ar, T& t, unsigned int v );
+
+// load_construct_data_adl
+
+template<class Ar, class T> void load_construct_data_adl( Ar& ar, T* t, unsigned int v );
+
+// save_construct_data_adl
+
+template<class Ar, class T> void save_construct_data_adl( Ar& ar, T const* t, unsigned int v );
+
+} // namespace core
+} // namespace boost
+``
+
+[endsect]
+
+[section `core_version_type`]
+
+``
+struct core_version_type
+{
+    unsigned int version_;
+
+    core_version_type( unsigned int version ): version_( version ) {}
+    operator unsigned int () const { return version_; }
+};
+``
+
+`core_version_type` is a Core reimplementation of
+`boost::serialization::version_type`, needed to call ADL serialization
+primitives such as, for example, `load_construct_data` below.
+
+It's defined in the `serialization` namespace instead of the `core`
+namespace because its only purpose is to add `boost::serialization` to
+the list of the associated namespaces of the corresponding call.
+
+[endsect]
+
+[section `split_free`]
+
+`template<class Ar, class T> inline void split_free( Ar& ar, T& t, unsigned int v );`
+
+`boost::core::split_free` is a Core reimplementation of
+`boost::serialization::split_free`.
+
+* *Effects:*
+  * If `Ar::is_saving::value` is `true`, calls `save( ar, t, core_version_type( v ) )`;
+  * Otherwise, calls `load( ar, t, core_version_type( v ) )`.
+
+[endsect]
+
+[section `split_member`]
+
+`template<class Ar, class T> void split_member( Ar& ar, T& t, unsigned int v );`
+
+`boost::core::split_member` is a Core reimplementation of
+`boost::serialization::split_member`.
+
+* *Effects:*
+  * If `Ar::is_saving::value` is `true`, calls `t.save( ar, v )`;
+  * Otherwise, calls `t.load( ar, v )`.
+
+[endsect]
+
+[section `load_construct_data_adl`]
+
+`template<class Ar, class T> void load_construct_data_adl( Ar& ar, T* t, unsigned int v );`
+
+`boost::core::load_construct_data_adl` is a Core reimplementation of
+`boost::serialization::load_construct_data_adl`.
+
+* *Effects:* `load_construct_data( ar, t, serialization::core_version_type( v ) );`.
+
+[endsect]
+
+[section `save_construct_data_adl`]
+
+`template<class Ar, class T> void save_construct_data_adl( Ar& ar, T const* t, unsigned int v );`
+
+`boost::core::save_construct_data_adl` is a Core reimplementation of
+`boost::serialization::save_construct_data_adl`.
+
+* *Effects:* `save_construct_data( ar, t, serialization::core_version_type( v ) );`.
+
+[endsect]
+
+[endsect]
+
+[endsect]

doc/span.qbk

@@ -227,13 +227,13 @@ constexpr span(R&& r);`]
 [`remove_cvref_t<R>` is not a specialization of `span`,]
 [`remove_cvref_t<R>` is not a specialization of `array`,]
 [`is_array_v<remove_cvref_t<R>>` is `false`,]
-[`r.data()` is well-formed and
+[`data(r)` is well-formed and
 `is_convertible_v<remove_pointer_t<iterator_t<R> >(*)[],
 T(*)[]>` is `true`, and]
 [`r.size()` is well-formed and
 `is_convertible_v<decltype(declval<R&>().size()), size_t>` is `true`.]]]]
-[[Effects][Constructs a `span` with data `r.data()` and size `r.size()`.]]
-[[Throws][What and when r.data() and r.size() throw.]]]]]
+[[Effects][Constructs a `span` with data `data(r)` and size `r.size()`.]]
+[[Throws][What and when data(r) and r.size() throw.]]]]]
 [[`explicit(E != dynamic_extent && N == dynamic_extent)
 template<class U, std::size_t N>
 constexpr span(const span<U, N>& s) noexcept;`]

include/boost/core/bit.hpp

@@ -20,6 +20,7 @@
 #include <boost/cstdint.hpp>
 #include <limits>
 #include <cstring>
+#include <cstdlib>
 
 #if defined(_MSC_VER)
 
@@ -38,6 +39,10 @@
 
 #endif // defined(_MSC_VER)
 
+#if defined(BOOST_MSVC) && BOOST_MSVC >= 1925
+# define BOOST_CORE_HAS_BUILTIN_ISCONSTEVAL
+#endif
+
 namespace boost
 {
 namespace core
@@ -102,10 +107,51 @@ BOOST_CONSTEXPR int countl_zero( T x ) BOOST_NOEXCEPT
 namespace detail
 {
 
+#if defined(_MSC_VER) && defined(BOOST_CORE_HAS_BUILTIN_ISCONSTEVAL)
+
+BOOST_CXX14_CONSTEXPR inline int countl_impl( boost::uint32_t x ) BOOST_NOEXCEPT
+{
+    if( __builtin_is_constant_evaluated() )
+    {
+        constexpr unsigned char mod37[ 37 ] = { 32, 31, 6, 30, 9, 5, 0, 29, 16, 8, 2, 4, 21, 0, 19, 28, 25, 15, 0, 7, 10, 1, 17, 3, 22, 20, 26, 0, 11, 18, 23, 27, 12, 24, 13, 14, 0 };
+
+        x |= x >> 1;
+        x |= x >> 2;
+        x |= x >> 4;
+        x |= x >> 8;
+        x |= x >> 16;
+
+        return mod37[ x % 37 ];
+    }
+    else
+    {
+        unsigned long r;
+
+        if( _BitScanReverse( &r, x ) )
+        {
+            return 31 - static_cast<int>( r );
+        }
+        else
+        {
+            return 32;
+        }
+    }
+}
+
+BOOST_CXX14_CONSTEXPR inline int countl_impl( boost::uint8_t x ) BOOST_NOEXCEPT
+{
+    return boost::core::detail::countl_impl( static_cast<boost::uint32_t>( x ) ) - 24;
+}
+
+BOOST_CXX14_CONSTEXPR inline int countl_impl( boost::uint16_t x ) BOOST_NOEXCEPT
+{
+    return boost::core::detail::countl_impl( static_cast<boost::uint32_t>( x ) ) - 16;
+}
+
+#elif defined(_MSC_VER)
+
 inline int countl_impl( boost::uint32_t x ) BOOST_NOEXCEPT
 {
-#if defined(_MSC_VER)
-
     unsigned long r;
 
     if( _BitScanReverse( &r, x ) )
@@ -116,44 +162,6 @@ inline int countl_impl( boost::uint32_t x ) BOOST_NOEXCEPT
     {
         return 32;
     }
-
-#else
-
-    static unsigned char const mod37[ 37 ] = { 32, 31, 6, 30, 9, 5, 0, 29, 16, 8, 2, 4, 21, 0, 19, 28, 25, 15, 0, 7, 10, 1, 17, 3, 22, 20, 26, 0, 11, 18, 23, 27, 12, 24, 13, 14, 0 };
-
-    x |= x >> 1;
-    x |= x >> 2;
-    x |= x >> 4;
-    x |= x >> 8;
-    x |= x >> 16;
-
-    return mod37[ x % 37 ];
-
-#endif
-}
-
-inline int countl_impl( boost::uint64_t x ) BOOST_NOEXCEPT
-{
-#if defined(_MSC_VER) && defined(_M_X64)
-
-    unsigned long r;
-
-    if( _BitScanReverse64( &r, x ) )
-    {
-        return 63 - static_cast<int>( r );
-    }
-    else
-    {
-        return 64;
-    }
-
-#else
-
-    return static_cast<boost::uint32_t>( x >> 32 ) != 0?
-        boost::core::detail::countl_impl( static_cast<boost::uint32_t>( x >> 32 ) ):
-        boost::core::detail::countl_impl( static_cast<boost::uint32_t>( x ) ) + 32;
-
-#endif
 }
 
 inline int countl_impl( boost::uint8_t x ) BOOST_NOEXCEPT
@@ -166,10 +174,98 @@ inline int countl_impl( boost::uint16_t x ) BOOST_NOEXCEPT
     return boost::core::detail::countl_impl( static_cast<boost::uint32_t>( x ) ) - 16;
 }
 
+#else
+
+inline int countl_impl( boost::uint32_t x ) BOOST_NOEXCEPT
+{
+    static unsigned char const mod37[ 37 ] = { 32, 31, 6, 30, 9, 5, 0, 29, 16, 8, 2, 4, 21, 0, 19, 28, 25, 15, 0, 7, 10, 1, 17, 3, 22, 20, 26, 0, 11, 18, 23, 27, 12, 24, 13, 14, 0 };
+
+    x |= x >> 1;
+    x |= x >> 2;
+    x |= x >> 4;
+    x |= x >> 8;
+    x |= x >> 16;
+
+    return mod37[ x % 37 ];
+}
+
+inline int countl_impl( boost::uint8_t x ) BOOST_NOEXCEPT
+{
+    return boost::core::detail::countl_impl( static_cast<boost::uint32_t>( x ) ) - 24;
+}
+
+inline int countl_impl( boost::uint16_t x ) BOOST_NOEXCEPT
+{
+    return boost::core::detail::countl_impl( static_cast<boost::uint32_t>( x ) ) - 16;
+}
+
+#endif
+
+#if defined(_MSC_VER) && defined(_M_X64) && defined(BOOST_CORE_HAS_BUILTIN_ISCONSTEVAL)
+
+BOOST_CXX14_CONSTEXPR inline int countl_impl( boost::uint64_t x ) BOOST_NOEXCEPT
+{
+    if( __builtin_is_constant_evaluated() )
+    {
+        return static_cast<boost::uint32_t>( x >> 32 ) != 0?
+            boost::core::detail::countl_impl( static_cast<boost::uint32_t>( x >> 32 ) ):
+            boost::core::detail::countl_impl( static_cast<boost::uint32_t>( x ) ) + 32;
+    }
+    else
+    {
+        unsigned long r;
+
+        if( _BitScanReverse64( &r, x ) )
+        {
+            return 63 - static_cast<int>( r );
+        }
+        else
+        {
+            return 64;
+        }
+    }
+}
+
+#elif defined(_MSC_VER) && defined(_M_X64)
+
+inline int countl_impl( boost::uint64_t x ) BOOST_NOEXCEPT
+{
+    unsigned long r;
+
+    if( _BitScanReverse64( &r, x ) )
+    {
+        return 63 - static_cast<int>( r );
+    }
+    else
+    {
+        return 64;
+    }
+}
+
+#elif defined(_MSC_VER) && defined(BOOST_CORE_HAS_BUILTIN_ISCONSTEVAL)
+
+BOOST_CXX14_CONSTEXPR inline int countl_impl( boost::uint64_t x ) BOOST_NOEXCEPT
+{
+    return static_cast<boost::uint32_t>( x >> 32 ) != 0?
+        boost::core::detail::countl_impl( static_cast<boost::uint32_t>( x >> 32 ) ):
+        boost::core::detail::countl_impl( static_cast<boost::uint32_t>( x ) ) + 32;
+}
+
+#else
+
+inline int countl_impl( boost::uint64_t x ) BOOST_NOEXCEPT
+{
+    return static_cast<boost::uint32_t>( x >> 32 ) != 0?
+        boost::core::detail::countl_impl( static_cast<boost::uint32_t>( x >> 32 ) ):
+        boost::core::detail::countl_impl( static_cast<boost::uint32_t>( x ) ) + 32;
+}
+
+#endif
+
 } // namespace detail
 
 template<class T>
-int countl_zero( T x ) BOOST_NOEXCEPT
+BOOST_CXX14_CONSTEXPR int countl_zero( T x ) BOOST_NOEXCEPT
 {
     BOOST_STATIC_ASSERT( std::numeric_limits<T>::is_integer && !std::numeric_limits<T>::is_signed );
 
@@ -250,10 +346,44 @@ BOOST_CONSTEXPR int countr_zero( T x ) BOOST_NOEXCEPT
 namespace detail
 {
 
+#if defined(_MSC_VER) && defined(BOOST_CORE_HAS_BUILTIN_ISCONSTEVAL)
+
+BOOST_CXX14_CONSTEXPR inline int countr_impl( boost::uint32_t x ) BOOST_NOEXCEPT
+{
+    if( __builtin_is_constant_evaluated() )
+    {
+        constexpr unsigned char mod37[ 37 ] = { 32, 0, 1, 26, 2, 23, 27, 0, 3, 16, 24, 30, 28, 11, 0, 13, 4, 7, 17, 0, 25, 22, 31, 15, 29, 10, 12, 6, 0, 21, 14, 9, 5, 20, 8, 19, 18 };
+        return mod37[ ( -(boost::int32_t)x & x ) % 37 ];
+    }
+    else
+    {
+        unsigned long r;
+
+        if( _BitScanForward( &r, x ) )
+        {
+            return static_cast<int>( r );
+        }
+        else
+        {
+            return 32;
+        }
+    }
+}
+
+BOOST_CXX14_CONSTEXPR inline int countr_impl( boost::uint8_t x ) BOOST_NOEXCEPT
+{
+    return boost::core::detail::countr_impl( static_cast<boost::uint32_t>( x ) | 0x100 );
+}
+
+BOOST_CXX14_CONSTEXPR inline int countr_impl( boost::uint16_t x ) BOOST_NOEXCEPT
+{
+    return boost::core::detail::countr_impl( static_cast<boost::uint32_t>( x ) | 0x10000 );
+}
+
+#elif defined(_MSC_VER)
+
 inline int countr_impl( boost::uint32_t x ) BOOST_NOEXCEPT
 {
-#if defined(_MSC_VER)
-
     unsigned long r;
 
     if( _BitScanForward( &r, x ) )
@@ -264,37 +394,6 @@ inline int countr_impl( boost::uint32_t x ) BOOST_NOEXCEPT
     {
         return 32;
     }
-
-#else
-
-    static unsigned char const mod37[ 37 ] = { 32, 0, 1, 26, 2, 23, 27, 0, 3, 16, 24, 30, 28, 11, 0, 13, 4, 7, 17, 0, 25, 22, 31, 15, 29, 10, 12, 6, 0, 21, 14, 9, 5, 20, 8, 19, 18 };
-    return mod37[ ( -(boost::int32_t)x & x ) % 37 ];
-
-#endif
-}
-
-inline int countr_impl( boost::uint64_t x ) BOOST_NOEXCEPT
-{
-#if defined(_MSC_VER) && defined(_M_X64)
-
-    unsigned long r;
-
-    if( _BitScanForward64( &r, x ) )
-    {
-        return static_cast<int>( r );
-    }
-    else
-    {
-        return 64;
-    }
-
-#else
-
-    return static_cast<boost::uint32_t>( x ) != 0?
-        boost::core::detail::countr_impl( static_cast<boost::uint32_t>( x ) ):
-        boost::core::detail::countr_impl( static_cast<boost::uint32_t>( x >> 32 ) ) + 32;
-
-#endif
 }
 
 inline int countr_impl( boost::uint8_t x ) BOOST_NOEXCEPT
@@ -307,10 +406,91 @@ inline int countr_impl( boost::uint16_t x ) BOOST_NOEXCEPT
     return boost::core::detail::countr_impl( static_cast<boost::uint32_t>( x ) | 0x10000 );
 }
 
+#else
+
+inline int countr_impl( boost::uint32_t x ) BOOST_NOEXCEPT
+{
+    static unsigned char const mod37[ 37 ] = { 32, 0, 1, 26, 2, 23, 27, 0, 3, 16, 24, 30, 28, 11, 0, 13, 4, 7, 17, 0, 25, 22, 31, 15, 29, 10, 12, 6, 0, 21, 14, 9, 5, 20, 8, 19, 18 };
+    return mod37[ ( -(boost::int32_t)x & x ) % 37 ];
+}
+
+inline int countr_impl( boost::uint8_t x ) BOOST_NOEXCEPT
+{
+    return boost::core::detail::countr_impl( static_cast<boost::uint32_t>( x ) | 0x100 );
+}
+
+inline int countr_impl( boost::uint16_t x ) BOOST_NOEXCEPT
+{
+    return boost::core::detail::countr_impl( static_cast<boost::uint32_t>( x ) | 0x10000 );
+}
+
+#endif
+
+#if defined(_MSC_VER) && defined(_M_X64) && defined(BOOST_CORE_HAS_BUILTIN_ISCONSTEVAL)
+
+BOOST_CXX14_CONSTEXPR inline int countr_impl( boost::uint64_t x ) BOOST_NOEXCEPT
+{
+    if( __builtin_is_constant_evaluated() )
+    {
+        return static_cast<boost::uint32_t>( x ) != 0?
+            boost::core::detail::countr_impl( static_cast<boost::uint32_t>( x ) ):
+            boost::core::detail::countr_impl( static_cast<boost::uint32_t>( x >> 32 ) ) + 32;
+    }
+    else
+    {
+        unsigned long r;
+
+        if( _BitScanForward64( &r, x ) )
+        {
+            return static_cast<int>( r );
+        }
+        else
+        {
+            return 64;
+        }
+    }
+}
+
+#elif defined(_MSC_VER) && defined(_M_X64)
+
+inline int countr_impl( boost::uint64_t x ) BOOST_NOEXCEPT
+{
+    unsigned long r;
+
+    if( _BitScanForward64( &r, x ) )
+    {
+        return static_cast<int>( r );
+    }
+    else
+    {
+        return 64;
+    }
+}
+
+#elif defined(_MSC_VER) && defined(BOOST_CORE_HAS_BUILTIN_ISCONSTEVAL)
+
+BOOST_CXX14_CONSTEXPR inline int countr_impl( boost::uint64_t x ) BOOST_NOEXCEPT
+{
+    return static_cast<boost::uint32_t>( x ) != 0?
+        boost::core::detail::countr_impl( static_cast<boost::uint32_t>( x ) ):
+        boost::core::detail::countr_impl( static_cast<boost::uint32_t>( x >> 32 ) ) + 32;
+}
+
+#else
+
+inline int countr_impl( boost::uint64_t x ) BOOST_NOEXCEPT
+{
+    return static_cast<boost::uint32_t>( x ) != 0?
+        boost::core::detail::countr_impl( static_cast<boost::uint32_t>( x ) ):
+        boost::core::detail::countr_impl( static_cast<boost::uint32_t>( x >> 32 ) ) + 32;
+}
+
+#endif
+
 } // namespace detail
 
 template<class T>
-int countr_zero( T x ) BOOST_NOEXCEPT
+BOOST_CXX14_CONSTEXPR int countr_zero( T x ) BOOST_NOEXCEPT
 {
     BOOST_STATIC_ASSERT( std::numeric_limits<T>::is_integer && !std::numeric_limits<T>::is_signed );
 
@@ -446,7 +626,7 @@ BOOST_CXX14_CONSTEXPR T rotl( T x, int s ) BOOST_NOEXCEPT
     BOOST_STATIC_ASSERT( std::numeric_limits<T>::is_integer && !std::numeric_limits<T>::is_signed );
 
     unsigned const mask = std::numeric_limits<T>::digits - 1;
-    return x << (s & mask) | x >> ((-s) & mask);
+    return static_cast<T>( x << (static_cast<unsigned>( s ) & mask) | x >> (static_cast<unsigned>( -s ) & mask) );
 }
 
 template<class T>
@@ -455,7 +635,7 @@ BOOST_CXX14_CONSTEXPR T rotr( T x, int s ) BOOST_NOEXCEPT
     BOOST_STATIC_ASSERT( std::numeric_limits<T>::is_integer && !std::numeric_limits<T>::is_signed );
 
     unsigned const mask = std::numeric_limits<T>::digits - 1;
-    return x >> (s & mask) | x << ((-s) & mask);
+    return static_cast<T>( x >> (static_cast<unsigned>( s ) & mask) | x << (static_cast<unsigned>( -s ) & mask) );
 }
 
 // integral powers of 2
@@ -484,7 +664,7 @@ BOOST_CONSTEXPR T bit_floor( T x ) BOOST_NOEXCEPT
 {
     BOOST_STATIC_ASSERT( std::numeric_limits<T>::is_integer && !std::numeric_limits<T>::is_signed );
 
-    return x == 0? 0: T(1) << ( boost::core::bit_width( x ) - 1 );
+    return x == 0? T(0): static_cast<T>( T(1) << ( boost::core::bit_width( x ) - 1 ) );
 }
 
 namespace detail
@@ -613,6 +793,117 @@ typedef endian::type endian_type;
 
 #undef BOOST_CORE_BIT_NATIVE_INITIALIZER
 
+// byteswap
+
+namespace detail
+{
+
+BOOST_CONSTEXPR inline boost::uint8_t byteswap_impl( boost::uint8_t x ) BOOST_NOEXCEPT
+{
+    return x;
+}
+
+BOOST_CONSTEXPR inline boost::uint16_t byteswap_impl( boost::uint16_t x ) BOOST_NOEXCEPT
+{
+    return static_cast<boost::uint16_t>( x << 8 | x >> 8 );
+}
+
+#if defined(__GNUC__) || defined(__clang__)
+
+BOOST_CXX14_CONSTEXPR inline boost::uint32_t byteswap_impl( boost::uint32_t x ) BOOST_NOEXCEPT
+{
+    return __builtin_bswap32( x );
+}
+
+BOOST_CXX14_CONSTEXPR inline boost::uint64_t byteswap_impl( boost::uint64_t x ) BOOST_NOEXCEPT
+{
+    return __builtin_bswap64( x );
+}
+
+#elif defined(_MSC_VER) && defined(BOOST_CORE_HAS_BUILTIN_ISCONSTEVAL)
+
+BOOST_CXX14_CONSTEXPR inline boost::uint32_t byteswap_impl( boost::uint32_t x ) BOOST_NOEXCEPT
+{
+    if( __builtin_is_constant_evaluated() )
+    {
+        boost::uint32_t step16 = x << 16 | x >> 16;
+        return ((step16 << 8) & 0xff00ff00) | ((step16 >> 8) & 0x00ff00ff);
+    }
+    else
+    {
+        return _byteswap_ulong( x );
+    }
+}
+
+BOOST_CXX14_CONSTEXPR inline boost::uint64_t byteswap_impl( boost::uint64_t x ) BOOST_NOEXCEPT
+{
+    if( __builtin_is_constant_evaluated() )
+    {
+        boost::uint64_t step32 = x << 32 | x >> 32;
+        boost::uint64_t step16 = (step32 & 0x0000FFFF0000FFFFULL) << 16 | (step32 & 0xFFFF0000FFFF0000ULL) >> 16;
+        return (step16 & 0x00FF00FF00FF00FFULL) << 8 | (step16 & 0xFF00FF00FF00FF00ULL) >> 8;
+    }
+    else
+    {
+        return _byteswap_uint64( x );
+    }
+}
+
+#elif defined(_MSC_VER)
+
+inline boost::uint32_t byteswap_impl( boost::uint32_t x ) BOOST_NOEXCEPT
+{
+    return _byteswap_ulong( x );
+}
+
+inline boost::uint64_t byteswap_impl( boost::uint64_t x ) BOOST_NOEXCEPT
+{
+    return _byteswap_uint64( x );
+}
+
+#else
+
+BOOST_CXX14_CONSTEXPR inline boost::uint32_t byteswap_impl( boost::uint32_t x ) BOOST_NOEXCEPT
+{
+    boost::uint32_t step16 = x << 16 | x >> 16;
+    return ((step16 << 8) & 0xff00ff00) | ((step16 >> 8) & 0x00ff00ff);
+}
+
+BOOST_CXX14_CONSTEXPR inline boost::uint64_t byteswap_impl( boost::uint64_t x ) BOOST_NOEXCEPT
+{
+    boost::uint64_t step32 = x << 32 | x >> 32;
+    boost::uint64_t step16 = (step32 & 0x0000FFFF0000FFFFULL) << 16 | (step32 & 0xFFFF0000FFFF0000ULL) >> 16;
+    return (step16 & 0x00FF00FF00FF00FFULL) << 8 | (step16 & 0xFF00FF00FF00FF00ULL) >> 8;
+}
+
+#endif
+
+} // namespace detail
+
+template<class T> BOOST_CXX14_CONSTEXPR T byteswap( T x ) BOOST_NOEXCEPT
+{
+    BOOST_STATIC_ASSERT( std::numeric_limits<T>::is_integer );
+
+    BOOST_STATIC_ASSERT( sizeof(T) == sizeof(boost::uint8_t) || sizeof(T) == sizeof(boost::uint16_t) || sizeof(T) == sizeof(boost::uint32_t) || sizeof(T) == sizeof(boost::uint64_t) );
+
+    BOOST_IF_CONSTEXPR ( sizeof(T) == sizeof(boost::uint8_t) )
+    {
+        return static_cast<T>( boost::core::detail::byteswap_impl( static_cast<boost::uint8_t>( x ) ) );
+    }
+    else BOOST_IF_CONSTEXPR ( sizeof(T) == sizeof(boost::uint16_t) )
+    {
+        return static_cast<T>( boost::core::detail::byteswap_impl( static_cast<boost::uint16_t>( x ) ) );
+    }
+    else BOOST_IF_CONSTEXPR ( sizeof(T) == sizeof(boost::uint32_t) )
+    {
+        return static_cast<T>( boost::core::detail::byteswap_impl( static_cast<boost::uint32_t>( x ) ) );
+    }
+    else
+    {
+        return static_cast<T>( boost::core::detail::byteswap_impl( static_cast<boost::uint64_t>( x ) ) );
+    }
+}
+
 } // namespace core
 } // namespace boost
 

include/boost/core/detail/lwt_unattended.hpp

@@ -35,9 +35,13 @@ inline void lwt_unattended()
 #  pragma clang diagnostic ignored "-Wdeprecated-declarations"
 # endif
 
+#if !defined(WINAPI_FAMILY) || WINAPI_FAMILY == 100 /*WINAPI_FAMILY_DESKTOP_APP*/
+
     // disable message box on crash
     ::_seterrormode( /*SEM_NOGPFAULTERRORBOX*/ 0x0002 );
 
+#endif
+
 # if defined(__clang__)
 #  pragma clang diagnostic pop
 # endif

include/boost/core/identity.hpp

@@ -0,0 +1,61 @@
+/*
+Copyright 2021-2023 Glen Joseph Fernandes
+(glenjofe@gmail.com)
+
+Distributed under the Boost Software License, Version 1.0.
+(http://www.boost.org/LICENSE_1_0.txt)
+*/
+#ifndef BOOST_CORE_IDENTITY_HPP
+#define BOOST_CORE_IDENTITY_HPP
+
+#include <boost/config.hpp>
+#if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
+#include <utility>
+#endif
+
+namespace boost {
+
+struct identity {
+    typedef void is_transparent;
+
+#if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
+    template<class T>
+    BOOST_CONSTEXPR T&& operator()(T&& value) const BOOST_NOEXCEPT {
+        return std::forward<T>(value);
+    }
+#else
+    template<class T>
+    BOOST_CONSTEXPR const T& operator()(const T& value) const BOOST_NOEXCEPT {
+        return value;
+    }
+
+    template<class T>
+    BOOST_CONSTEXPR T& operator()(T& value) const BOOST_NOEXCEPT {
+        return value;
+    }
+#endif
+
+    template<class>
+    struct result { };
+
+    template<class T>
+    struct result<identity(T&)> {
+        typedef T& type;
+    };
+
+#if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
+    template<class T>
+    struct result<identity(T)> {
+        typedef T&& type;
+    };
+
+    template<class T>
+    struct result<identity(T&&)> {
+        typedef T&& type;
+    };
+#endif
+};
+
+} /* boost */
+
+#endif

include/boost/core/span.hpp

@@ -8,11 +8,10 @@ Distributed under the Boost Software License, Version 1.0.
 #ifndef BOOST_CORE_SPAN_HPP
 #define BOOST_CORE_SPAN_HPP
 
+#include <boost/core/data.hpp>
 #include <array>
-#include <initializer_list>
 #include <iterator>
 #include <type_traits>
-#include <cstddef>
 
 namespace boost {
 
@@ -63,29 +62,8 @@ struct span_is_array<std::array<T, N> > {
     static constexpr bool value = true;
 };
 
-template<class C>
-inline constexpr auto
-span_begin(C& c) noexcept(noexcept(c.data())) -> decltype(c.data())
-{
-    return c.data();
-}
-
-template<class C>
-inline constexpr auto
-span_begin(const C& c) noexcept(noexcept(c.data())) -> decltype(c.data())
-{
-    return c.data();
-}
-
 template<class T>
-inline constexpr const T*
-span_begin(std::initializer_list<T> l) noexcept
-{
-    return l.begin();
-}
-
-template<class T>
-using span_ptr = decltype(boost::detail::span_begin(std::declval<T&>()));
+using span_ptr = decltype(boost::data(std::declval<T&>()));
 
 template<class, class = void>
 struct span_data { };
@@ -245,16 +223,16 @@ public:
     template<class R,
         typename std::enable_if<E == dynamic_extent &&
             detail::span_is_range<R, T>::value, int>::type = 0>
-    constexpr span(R&& r) noexcept(noexcept(detail::span_begin(r)) &&
+    constexpr span(R&& r) noexcept(noexcept(boost::data(r)) &&
         noexcept(r.size()))
-        : s_(detail::span_begin(r), r.size()) { }
+        : s_(boost::data(r), r.size()) { }
 
     template<class R,
         typename std::enable_if<E != dynamic_extent &&
             detail::span_is_range<R, T>::value, int>::type = 0>
-    explicit constexpr span(R&& r) noexcept(noexcept(detail::span_begin(r)) &&
+    explicit constexpr span(R&& r) noexcept(noexcept(boost::data(r)) &&
         noexcept(r.size()))
-        : s_(detail::span_begin(r), r.size()) { }
+        : s_(boost::data(r), r.size()) { }
 
     template<class U, std::size_t N,
         typename std::enable_if<detail::span_implicit<E, N>::value &&

include/boost/core/type_name.hpp

@@ -102,11 +102,23 @@ inline std::string fix_typeid_name( char const* n )
     return r;
 }
 
-template<class T> std::string typeid_name()
+// class types can be incomplete
+template<class T> std::string typeid_name_impl( int T::* )
+{
+    std::string r = fix_typeid_name( typeid(T[1]).name() );
+    return r.substr( 0, r.size() - 4 ); // remove ' [1]' suffix
+}
+
+template<class T> std::string typeid_name_impl( ... )
 {
     return fix_typeid_name( typeid(T).name() );
 }
 
+template<class T> std::string typeid_name()
+{
+    return typeid_name_impl<T>( 0 );
+}
+
 // template names
 
 template<class T> std::string class_template_name()
@@ -862,6 +874,8 @@ template<class T, std::size_t N> struct tn_holder<T const volatile[N]>
 
 // pointers to members
 
+#if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES)
+
 template<class R, class T> struct tn_holder<R T::*>
 {
     static std::string type_name( std::string const& suffix )
@@ -870,7 +884,7 @@ template<class R, class T> struct tn_holder<R T::*>
     }
 };
 
-#if defined(BOOST_MSVC) && BOOST_MSVC < 1900 && !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES)
+#if defined(BOOST_MSVC) && BOOST_MSVC < 1900
 
 template<class R, class T, class... A> struct tn_holder<R(T::*)(A...)>
 {
@@ -904,7 +918,9 @@ template<class R, class T, class... A> struct tn_holder<R(T::*)(A...) const vola
     }
 };
 
-#endif
+#endif // #if defined(BOOST_MSVC) && BOOST_MSVC < 1900
+
+#endif // #if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES)
 
 // strings
 

test/Jamfile.v2

@@ -98,6 +98,8 @@ run visit_each_test.cpp ;
 run get_pointer_test.cpp ;
 
 local pedantic-errors = <warnings>pedantic
+    <toolset>gcc:<cxxflags>"-Wconversion"
+    <toolset>clang:<cxxflags>"-Wconversion"
     <toolset>msvc:<warnings-as-errors>on
     <toolset>gcc:<warnings-as-errors>on
     <toolset>clang:<warnings-as-errors>on ;
@@ -296,10 +298,22 @@ run bit_popcount_test.cpp
   : : : $(pedantic-errors) ;
 run bit_endian_test.cpp
   : : : $(pedantic-errors) ;
+run bit_byteswap_test.cpp
+  : : : $(pedantic-errors) ;
 
 compile-fail bit_width_fail.cpp
   : <warnings>off ;
 
+compile bit_rotate_test_cx.cpp ;
+compile bit_countr_test_cx.cpp ;
+compile bit_countl_test_cx.cpp ;
+compile bit_width_test_cx.cpp ;
+compile has_single_bit_test_cx.cpp ;
+compile bit_floor_test_cx.cpp ;
+compile bit_ceil_test_cx.cpp ;
+compile bit_popcount_test_cx.cpp ;
+compile bit_byteswap_test_cx.cpp ;
+
 run type_name_test.cpp ;
 
 run snprintf_test.cpp ;
@@ -363,10 +377,13 @@ run memory_resource_test.cpp ;
 run data_test.cpp ;
 run size_test.cpp ;
 
-run serialization_nvp_test.cpp : : : <library>/boost//serialization/<warnings>off <toolset>clang,<undefined-sanitizer>norecover:<build>no ;
-run serialization_split_free_test.cpp : : : <library>/boost//serialization/<warnings>off ;
-run serialization_split_member_test.cpp : : : <library>/boost//serialization/<warnings>off ;
-run serialization_construct_data_test.cpp : : : <library>/boost//serialization/<warnings>off ;
+run serialization_nvp_test.cpp : : : <library>/boost//serialization/<warnings>off <undefined-sanitizer>norecover:<build>no ;
+run serialization_split_free_test.cpp : : : <library>/boost//serialization/<warnings>off <undefined-sanitizer>norecover:<link>static ;
+run serialization_split_member_test.cpp : : : <library>/boost//serialization/<warnings>off <undefined-sanitizer>norecover:<link>static ;
+run serialization_construct_data_test.cpp : : : <library>/boost//serialization/<warnings>off <undefined-sanitizer>norecover:<link>static ;
+
+run identity_test.cpp ;
+run identity_rvalue_test.cpp ;
 
 use-project /boost/core/swap : ./swap ;
 build-project ./swap ;

test/bit_byteswap_test.cpp

@@ -0,0 +1,26 @@
+// Test for boost/core/bit.hpp (byteswap)
+//
+// Copyright 2023 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/core/bit.hpp>
+#include <boost/core/lightweight_test.hpp>
+#include <boost/cstdint.hpp>
+
+int main()
+{
+    BOOST_TEST_EQ( boost::core::byteswap( (boost::int8_t)0x01 ), 0x01 );
+    BOOST_TEST_EQ( boost::core::byteswap( (boost::uint8_t)0xF1 ), 0xF1 );
+
+    BOOST_TEST_EQ( boost::core::byteswap( (boost::int16_t)0x0102 ), 0x0201 );
+    BOOST_TEST_EQ( boost::core::byteswap( (boost::uint16_t)0xF1E2 ), 0xE2F1 );
+
+    BOOST_TEST_EQ( boost::core::byteswap( (boost::int32_t)0x01020304 ), 0x04030201 );
+    BOOST_TEST_EQ( boost::core::byteswap( (boost::uint32_t)0xF1E2D3C4u ), 0xC4D3E2F1u );
+
+    BOOST_TEST_EQ( boost::core::byteswap( (boost::int64_t)0x01020304 << 32 | 0x05060708 ), (boost::int64_t)0x08070605 << 32 | 0x04030201 );
+    BOOST_TEST_EQ( boost::core::byteswap( (boost::uint64_t)0xF1E2D3C4u << 32 | 0xB5A69788u ), (boost::uint64_t)0x8897A6B5u << 32 | 0xC4D3E2F1u );
+
+    return boost::report_errors();
+}

test/bit_byteswap_test_cx.cpp

@@ -0,0 +1,37 @@
+// constexpr test for boost/core/bit.hpp (bit_width)
+//
+// Copyright 2023 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/config.hpp>
+#include <boost/config/pragma_message.hpp>
+
+#if defined(BOOST_NO_CXX14_CONSTEXPR)
+
+BOOST_PRAGMA_MESSAGE( "Test skipped because BOOST_NO_CXX14_CONSTEXPR is defined" )
+
+#elif defined(BOOST_MSVC) && BOOST_MSVC / 10 == 191
+
+BOOST_PRAGMA_MESSAGE( "Test skipped because BOOST_MSVC is " BOOST_STRINGIZE(BOOST_MSVC) )
+
+#else
+
+#include <boost/core/bit.hpp>
+#include <cstdint>
+
+#define STATIC_ASSERT(...) static_assert(__VA_ARGS__, #__VA_ARGS__)
+
+STATIC_ASSERT( boost::core::byteswap( (std::int8_t)0x01 ) == 0x01 );
+STATIC_ASSERT( boost::core::byteswap( (std::uint8_t)0xF1 ) == 0xF1 );
+
+STATIC_ASSERT( boost::core::byteswap( (std::int16_t)0x0102 ) == 0x0201 );
+STATIC_ASSERT( boost::core::byteswap( (std::uint16_t)0xF1E2 ) == 0xE2F1 );
+
+STATIC_ASSERT( boost::core::byteswap( (std::int32_t)0x01020304 ) == 0x04030201 );
+STATIC_ASSERT( boost::core::byteswap( (std::uint32_t)0xF1E2D3C4u ) == 0xC4D3E2F1u );
+
+STATIC_ASSERT( boost::core::byteswap( (std::int64_t)0x0102030405060708ll ) == 0x0807060504030201ll );
+STATIC_ASSERT( boost::core::byteswap( (std::uint64_t)0xF1E2D3C4B5A69788ull ) == 0x8897A6B5C4D3E2F1ull );
+
+#endif

test/bit_ceil_test.cpp

@@ -14,7 +14,7 @@ template<class T> void test_bit_ceil( T x )
 {
     if( !boost::core::has_single_bit( x ) )
     {
-        x >>= 1;
+        x = static_cast<T>( x >> 1 );
     }
 
     T y = boost::core::bit_ceil( x );

test/bit_ceil_test_cx.cpp

@@ -0,0 +1,26 @@
+// constexpr test for boost/core/bit.hpp (bit_ceil)
+//
+// Copyright 2023 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/config.hpp>
+#include <boost/config/pragma_message.hpp>
+
+#if defined(BOOST_NO_CXX14_CONSTEXPR)
+
+BOOST_PRAGMA_MESSAGE( "Test skipped because BOOST_NO_CXX14_CONSTEXPR is defined" )
+
+#else
+
+#include <boost/core/bit.hpp>
+
+#define STATIC_ASSERT(...) static_assert(__VA_ARGS__, #__VA_ARGS__)
+
+STATIC_ASSERT( boost::core::bit_ceil( (unsigned char)0x74 ) == 0x80 );
+STATIC_ASSERT( boost::core::bit_ceil( (unsigned short)0x7400 ) == 0x8000 );
+STATIC_ASSERT( boost::core::bit_ceil( 0x740000u ) == 0x800000u );
+STATIC_ASSERT( boost::core::bit_ceil( 0x74000000ul ) == 0x80000000ul );
+STATIC_ASSERT( boost::core::bit_ceil( 0x7400000000ull ) == 0x8000000000ull );
+
+#endif

test/bit_countl_test.cpp

@@ -14,7 +14,7 @@ template<class T> void test_countl( T x )
 {
     x |= static_cast<T>( 1 ) << ( std::numeric_limits<T>::digits - 1 );
 
-    for( int i = 0; i <= std::numeric_limits<T>::digits; ++i, x >>= 1 )
+    for( int i = 0; i <= std::numeric_limits<T>::digits; ++i, x = static_cast<T>( x >> 1 ) )
     {
         BOOST_TEST_EQ( boost::core::countl_zero( x ), i );
         BOOST_TEST_EQ( boost::core::countl_one( static_cast<T>( ~x ) ), i );

test/bit_countl_test_cx.cpp

@@ -0,0 +1,41 @@
+// constexpr test for boost/core/bit.hpp (countl_zero, countl_one)
+//
+// Copyright 2023 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#if defined(_MSC_VER)
+# pragma warning(disable: 4310) // cast truncates constant value
+#endif
+
+#include <boost/config.hpp>
+#include <boost/config/pragma_message.hpp>
+
+#if defined(BOOST_NO_CXX14_CONSTEXPR)
+
+BOOST_PRAGMA_MESSAGE( "Test skipped because BOOST_NO_CXX14_CONSTEXPR is defined" )
+
+#elif defined(BOOST_MSVC) && BOOST_MSVC / 10 == 191
+
+BOOST_PRAGMA_MESSAGE( "Test skipped because BOOST_MSVC is " BOOST_STRINGIZE(BOOST_MSVC) )
+
+#else
+
+#include <boost/core/bit.hpp>
+#include <climits>
+
+#define STATIC_ASSERT(...) static_assert(__VA_ARGS__, #__VA_ARGS__)
+
+STATIC_ASSERT( boost::core::countl_zero( (unsigned char)0x1F ) == CHAR_BIT - 5 );
+STATIC_ASSERT( boost::core::countl_zero( (unsigned short)0x1F ) == sizeof(unsigned short) * CHAR_BIT - 5 );
+STATIC_ASSERT( boost::core::countl_zero( 0x1Fu ) == sizeof(unsigned int) * CHAR_BIT - 5 );
+STATIC_ASSERT( boost::core::countl_zero( 0x1Ful ) == sizeof(unsigned long) * CHAR_BIT - 5 );
+STATIC_ASSERT( boost::core::countl_zero( 0x1Full ) == sizeof(unsigned long long) * CHAR_BIT - 5 );
+
+STATIC_ASSERT( boost::core::countl_one( (unsigned char)~0x1Fu ) == CHAR_BIT - 5 );
+STATIC_ASSERT( boost::core::countl_one( (unsigned short)~0x1Fu ) == sizeof(unsigned short) * CHAR_BIT - 5 );
+STATIC_ASSERT( boost::core::countl_one( ~0x1Fu ) == sizeof(unsigned int) * CHAR_BIT - 5 );
+STATIC_ASSERT( boost::core::countl_one( ~0x1Ful ) == sizeof(unsigned long) * CHAR_BIT - 5 );
+STATIC_ASSERT( boost::core::countl_one( ~0x1Full ) == sizeof(unsigned long long) * CHAR_BIT - 5 );
+
+#endif

test/bit_countr_test.cpp

@@ -14,7 +14,7 @@ template<class T> void test_countr( T x )
 {
     x |= 1;
 
-    for( int i = 0; i <= std::numeric_limits<T>::digits; ++i, x <<= 1 )
+    for( int i = 0; i <= std::numeric_limits<T>::digits; ++i, x = static_cast<T>( x << 1 ) )
     {
         BOOST_TEST_EQ( boost::core::countr_zero( x ), i );
         BOOST_TEST_EQ( boost::core::countr_one( static_cast<T>( ~x ) ), i );

test/bit_countr_test_cx.cpp

@@ -0,0 +1,41 @@
+// constexpr test for boost/core/bit.hpp (countr_zero, countr_one)
+//
+// Copyright 2023 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#if defined(_MSC_VER)
+# pragma warning(disable: 4310) // cast truncates constant value
+#endif
+
+#include <boost/config.hpp>
+#include <boost/config/pragma_message.hpp>
+
+#if defined(BOOST_NO_CXX14_CONSTEXPR)
+
+BOOST_PRAGMA_MESSAGE( "Test skipped because BOOST_NO_CXX14_CONSTEXPR is defined" )
+
+#elif defined(BOOST_MSVC) && BOOST_MSVC / 10 == 191
+
+BOOST_PRAGMA_MESSAGE( "Test skipped because BOOST_MSVC is " BOOST_STRINGIZE(BOOST_MSVC) )
+
+#else
+
+#include <boost/core/bit.hpp>
+#include <climits>
+
+#define STATIC_ASSERT(...) static_assert(__VA_ARGS__, #__VA_ARGS__)
+
+STATIC_ASSERT( boost::core::countr_zero( (unsigned char)0xF8 ) == 3 );
+STATIC_ASSERT( boost::core::countr_zero( (unsigned short)0xF800 ) == 11 );
+STATIC_ASSERT( boost::core::countr_zero( 0xF80000u ) == 19 );
+STATIC_ASSERT( boost::core::countr_zero( 0xF8000000ul ) == 27 );
+STATIC_ASSERT( boost::core::countr_zero( 0xF800000000ull ) == 35 );
+
+STATIC_ASSERT( boost::core::countr_one( (unsigned char)~0xF8u ) == 3 );
+STATIC_ASSERT( boost::core::countr_one( (unsigned short)~0xF800u ) == 11 );
+STATIC_ASSERT( boost::core::countr_one( ~0xF80000u ) == 19 );
+STATIC_ASSERT( boost::core::countr_one( ~0xF8000000ul ) == 27 );
+STATIC_ASSERT( boost::core::countr_one( ~0xF800000000ull ) == 35 );
+
+#endif

test/bit_floor_test_cx.cpp

@@ -0,0 +1,30 @@
+// constexpr test for boost/core/bit.hpp (bit_floor)
+//
+// Copyright 2023 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/config.hpp>
+#include <boost/config/pragma_message.hpp>
+
+#if defined(BOOST_NO_CXX14_CONSTEXPR)
+
+BOOST_PRAGMA_MESSAGE( "Test skipped because BOOST_NO_CXX14_CONSTEXPR is defined" )
+
+#elif defined(BOOST_MSVC) && BOOST_MSVC / 10 == 191
+
+BOOST_PRAGMA_MESSAGE( "Test skipped because BOOST_MSVC is " BOOST_STRINGIZE(BOOST_MSVC) )
+
+#else
+
+#include <boost/core/bit.hpp>
+
+#define STATIC_ASSERT(...) static_assert(__VA_ARGS__, #__VA_ARGS__)
+
+STATIC_ASSERT( boost::core::bit_floor( (unsigned char)0x74 ) == 0x40 );
+STATIC_ASSERT( boost::core::bit_floor( (unsigned short)0x7400 ) == 0x4000 );
+STATIC_ASSERT( boost::core::bit_floor( 0x740000u ) == 0x400000u );
+STATIC_ASSERT( boost::core::bit_floor( 0x74000000ul ) == 0x40000000ul );
+STATIC_ASSERT( boost::core::bit_floor( 0x7400000000ull ) == 0x4000000000ull );
+
+#endif

test/bit_popcount_test.cpp

@@ -1,4 +1,4 @@
-// Test for boost/core/bit.hpp (bit_ceil)
+// Test for boost/core/bit.hpp (popcount)
 //
 // Copyright 2020 Peter Dimov
 // Distributed under the Boost Software License, Version 1.0.
@@ -14,7 +14,7 @@
 template<class T> void test_popcount( T x )
 {
     int k = 0;
-    for( T y = x; y; y &= y - 1, ++k );
+    for( T y = x; y; y = static_cast<T>( y & (y - 1) ), ++k );
 
     BOOST_TEST_EQ( boost::core::popcount( x ), k ) || ( std::cerr << "x: " << +x << std::endl );
 }

test/bit_popcount_test_cx.cpp

@@ -0,0 +1,30 @@
+// constexpr test for boost/core/bit.hpp (popcount)
+//
+// Copyright 2023 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#if defined(_MSC_VER) && _MSC_VER / 10 == 191
+# pragma warning(disable: 4307) // '*': integral constant overflow
+#endif
+
+#include <boost/config.hpp>
+#include <boost/config/pragma_message.hpp>
+
+#if defined(BOOST_NO_CXX14_CONSTEXPR)
+
+BOOST_PRAGMA_MESSAGE( "Test skipped because BOOST_NO_CXX14_CONSTEXPR is defined" )
+
+#else
+
+#include <boost/core/bit.hpp>
+
+#define STATIC_ASSERT(...) static_assert(__VA_ARGS__, #__VA_ARGS__)
+
+STATIC_ASSERT( boost::core::popcount( (unsigned char)0x74 ) == 4 );
+STATIC_ASSERT( boost::core::popcount( (unsigned short)0x7400 ) == 4 );
+STATIC_ASSERT( boost::core::popcount( 0x740000u ) == 4 );
+STATIC_ASSERT( boost::core::popcount( 0x74000000ul ) == 4 );
+STATIC_ASSERT( boost::core::popcount( 0x7400000000ull ) == 4 );
+
+#endif

test/bit_rotate_test.cpp

@@ -20,7 +20,7 @@ template<class T> void test_rotate( T x )
         BOOST_TEST_EQ( +boost::core::rotl( x, -i ), +boost::core::rotr( x, i ) );
 
         unsigned const width = std::numeric_limits<T>::digits;
-        unsigned r = i & ( width - 1 );
+        unsigned r = static_cast<unsigned>( i ) & ( width - 1 );
 
         if( r == 0 )
         {

test/bit_rotate_test_cx.cpp

@@ -0,0 +1,33 @@
+// constexpr test for boost/core/bit.hpp (rotl, rotr)
+//
+// Copyright 2023 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/config.hpp>
+#include <boost/config/pragma_message.hpp>
+
+#if defined(BOOST_NO_CXX14_CONSTEXPR)
+
+BOOST_PRAGMA_MESSAGE( "Test skipped because BOOST_NO_CXX14_CONSTEXPR is defined" )
+
+#else
+
+#include <boost/core/bit.hpp>
+#include <cstdint>
+
+#define STATIC_ASSERT(...) static_assert(__VA_ARGS__, #__VA_ARGS__)
+
+STATIC_ASSERT( boost::core::rotl( (std::uint8_t)0x11, 1 ) == 0x22 );
+STATIC_ASSERT( boost::core::rotr( (std::uint8_t)0x11, 1 ) == 0x88 );
+
+STATIC_ASSERT( boost::core::rotl( (std::uint16_t)0x1111, 1 ) == 0x2222 );
+STATIC_ASSERT( boost::core::rotr( (std::uint16_t)0x1111, 1 ) == 0x8888 );
+
+STATIC_ASSERT( boost::core::rotl( (std::uint32_t)0x11111111, 1 ) == 0x22222222 );
+STATIC_ASSERT( boost::core::rotr( (std::uint32_t)0x11111111, 1 ) == 0x88888888 );
+
+STATIC_ASSERT( boost::core::rotl( (std::uint64_t)0x1111111111111111, 1 ) == 0x2222222222222222 );
+STATIC_ASSERT( boost::core::rotr( (std::uint64_t)0x1111111111111111, 1 ) == 0x8888888888888888 );
+
+#endif

test/bit_width_test.cpp

@@ -24,7 +24,7 @@ int main()
 
         x = 1;
 
-        for( int i = 0; i < 8; ++i, x <<= 1 )
+        for( int i = 0; i < 8; ++i, x = static_cast<boost::uint8_t>( x << 1 ) )
         {
             BOOST_TEST_EQ( boost::core::bit_width( x ), i+1 );
             BOOST_TEST_EQ( boost::core::bit_width( static_cast<boost::uint8_t>( x | ( x >> 1 ) ) ), i+1 );
@@ -39,7 +39,7 @@ int main()
 
         x = 1;
 
-        for( int i = 0; i < 16; ++i, x <<= 1 )
+        for( int i = 0; i < 16; ++i, x = static_cast<boost::uint16_t>( x << 1 ) )
         {
             BOOST_TEST_EQ( boost::core::bit_width( x ), i+1 );
             BOOST_TEST_EQ( boost::core::bit_width( static_cast<boost::uint16_t>( x | ( x >> 1 ) ) ), i+1 );

test/bit_width_test_cx.cpp

@@ -0,0 +1,30 @@
+// constexpr test for boost/core/bit.hpp (bit_width)
+//
+// Copyright 2023 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/config.hpp>
+#include <boost/config/pragma_message.hpp>
+
+#if defined(BOOST_NO_CXX14_CONSTEXPR)
+
+BOOST_PRAGMA_MESSAGE( "Test skipped because BOOST_NO_CXX14_CONSTEXPR is defined" )
+
+#elif defined(BOOST_MSVC) && BOOST_MSVC / 10 == 191
+
+BOOST_PRAGMA_MESSAGE( "Test skipped because BOOST_MSVC is " BOOST_STRINGIZE(BOOST_MSVC) )
+
+#else
+
+#include <boost/core/bit.hpp>
+
+#define STATIC_ASSERT(...) static_assert(__VA_ARGS__, #__VA_ARGS__)
+
+STATIC_ASSERT( boost::core::bit_width( (unsigned char)0x74 ) == 7 );
+STATIC_ASSERT( boost::core::bit_width( (unsigned short)0x7400 ) == 15 );
+STATIC_ASSERT( boost::core::bit_width( 0x740000u ) == 23 );
+STATIC_ASSERT( boost::core::bit_width( 0x74000000ul ) == 31 );
+STATIC_ASSERT( boost::core::bit_width( 0x7400000000ull ) == 39 );
+
+#endif

test/has_single_bit_test.cpp

@@ -28,7 +28,7 @@ int main()
 
         x = 2;
 
-        for( int i = 1; i < 8; ++i, x <<= 1 )
+        for( int i = 1; i < 8; ++i, x = static_cast<boost::uint8_t>( x << 1 ) )
         {
             BOOST_TEST_EQ( boost::core::has_single_bit( x ), true );
             BOOST_TEST_EQ( boost::core::has_single_bit( static_cast<boost::uint8_t>( x | ( x >> 1 ) ) ), false );
@@ -47,7 +47,7 @@ int main()
 
         x = 2;
 
-        for( int i = 1; i < 16; ++i, x <<= 1 )
+        for( int i = 1; i < 16; ++i, x = static_cast<boost::uint16_t>( x << 1 ) )
         {
             BOOST_TEST_EQ( boost::core::has_single_bit( x ), true );
             BOOST_TEST_EQ( boost::core::has_single_bit( static_cast<boost::uint16_t>( x | ( x >> 1 ) ) ), false );

test/has_single_bit_test_cx.cpp

@@ -0,0 +1,35 @@
+// constexpr test for boost/core/bit.hpp (has_single_bit)
+//
+// Copyright 2023 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/config.hpp>
+#include <boost/config/pragma_message.hpp>
+
+#if defined(BOOST_NO_CXX14_CONSTEXPR)
+
+BOOST_PRAGMA_MESSAGE( "Test skipped because BOOST_NO_CXX14_CONSTEXPR is defined" )
+
+#else
+
+#include <boost/core/bit.hpp>
+
+#define STATIC_ASSERT(...) static_assert(__VA_ARGS__, #__VA_ARGS__)
+
+STATIC_ASSERT( boost::core::has_single_bit( (unsigned char)0x80 ) == true );
+STATIC_ASSERT( boost::core::has_single_bit( (unsigned char)0x90 ) == false );
+
+STATIC_ASSERT( boost::core::has_single_bit( (unsigned short)0x8000 ) == true );
+STATIC_ASSERT( boost::core::has_single_bit( (unsigned short)0x9000 ) == false );
+
+STATIC_ASSERT( boost::core::has_single_bit( 0x800000u ) == true );
+STATIC_ASSERT( boost::core::has_single_bit( 0x900000u ) == false );
+
+STATIC_ASSERT( boost::core::has_single_bit( 0x80000000ul ) == true );
+STATIC_ASSERT( boost::core::has_single_bit( 0x90000000ul ) == false );
+
+STATIC_ASSERT( boost::core::has_single_bit( 0x8000000000ull ) == true );
+STATIC_ASSERT( boost::core::has_single_bit( 0x9000000000ull ) == false );
+
+#endif

test/identity_rvalue_test.cpp

@@ -0,0 +1,69 @@
+/*
+Copyright 2021-2023 Glen Joseph Fernandes
+(glenjofe@gmail.com)
+
+Distributed under the Boost Software License, Version 1.0.
+(http://www.boost.org/LICENSE_1_0.txt)
+*/
+#include <boost/config.hpp>
+#if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
+#include <boost/core/identity.hpp>
+#include <boost/core/lightweight_test.hpp>
+#include <algorithm>
+#include <iterator>
+#include <string>
+#include <vector>
+
+bool test(std::string&&)
+{
+    return true;
+}
+
+bool test(const std::string&&)
+{
+    return true;
+}
+
+template<class T>
+bool test(T&&)
+{
+    return false;
+}
+
+void simple_test()
+{
+    typedef std::string string;
+    BOOST_TEST(boost::identity()(string("a")) == string("a"));
+    BOOST_TEST(test(boost::identity()(string("a"))));
+    typedef const std::string cstring;
+    BOOST_TEST(boost::identity()(cstring("a")) == cstring("a"));
+    BOOST_TEST(test(boost::identity()(cstring("a"))));
+}
+
+void algorithm_test()
+{
+    std::vector<std::string> v1;
+    v1.push_back(std::string("a"));
+    v1.push_back(std::string("b"));
+    v1.push_back(std::string("c"));
+    std::vector<std::string> v2(v1);
+    std::vector<std::string> v3;
+    std::transform(std::make_move_iterator(v2.begin()),
+        std::make_move_iterator(v2.end()),
+        std::back_inserter(v3),
+        boost::identity());
+    BOOST_TEST(v3 == v1);
+}
+
+int main()
+{
+    simple_test();
+    algorithm_test();
+    return boost::report_errors();
+}
+#else
+int main()
+{
+    return 0;
+}
+#endif

test/identity_test.cpp

@@ -0,0 +1,66 @@
+/*
+Copyright 2021-2023 Glen Joseph Fernandes
+(glenjofe@gmail.com)
+
+Distributed under the Boost Software License, Version 1.0.
+(http://www.boost.org/LICENSE_1_0.txt)
+*/
+#include <boost/core/identity.hpp>
+#include <boost/core/lightweight_test.hpp>
+#include <algorithm>
+#include <iterator>
+#include <string>
+#include <vector>
+
+bool test(std::string&)
+{
+    return true;
+}
+
+bool test(const std::string&)
+{
+    return true;
+}
+
+template<class T>
+bool test(T&)
+{
+    return false;
+}
+
+template<class T>
+bool test(const T&)
+{
+    return false;
+}
+
+void simple_test()
+{
+    std::string s1("a");
+    BOOST_TEST(boost::identity()(s1) == s1);
+    BOOST_TEST(&boost::identity()(s1) == &s1);
+    BOOST_TEST(test(boost::identity()(s1)));
+    const std::string s2("a");
+    BOOST_TEST(boost::identity()(s2) == s2);
+    BOOST_TEST(&boost::identity()(s2) == &s2);
+    BOOST_TEST(test(boost::identity()(s2)));
+}
+
+void algorithm_test()
+{
+    std::vector<std::string> v1;
+    v1.push_back(std::string("a"));
+    v1.push_back(std::string("b"));
+    v1.push_back(std::string("c"));
+    std::vector<std::string> v2;
+    std::transform(v1.begin(), v1.end(), std::back_inserter(v2),
+         boost::identity());
+    BOOST_TEST(v2 == v1);
+}
+
+int main()
+{
+    simple_test();
+    algorithm_test();
+    return boost::report_errors();
+}

test/max_align_test.cpp

@@ -54,16 +54,9 @@ int main()
     BOOST_TEST_GE( boost::core::max_align, boost::alignment_of<void (X::*)()>::value );
 
 #if !defined(BOOST_NO_CXX11_ALIGNOF) && !defined(BOOST_NO_STD_MAX_ALIGN_T)
-# if defined(BOOST_LIBSTDCXX_VERSION) && BOOST_LIBSTDCXX_VERSION < 70000
 
-    // libstdc++ 7 adds __float128 to std::max_align_t, but we always have it
     BOOST_TEST_GE( boost::core::max_align, alignof( std::max_align_t ) );
 
-# else
-
-    BOOST_TEST_EQ( boost::core::max_align, alignof( std::max_align_t ) );
-
-# endif
 #endif
 
     return boost::report_errors();

test/type_name_test.cpp

@@ -47,10 +47,14 @@ class B
 {
 };
 
+class C;
+
 template<class T1, class T2> struct X
 {
 };
 
+template<class T1, class T2> struct Y;
+
 enum E1
 {
     e1
@@ -63,6 +67,8 @@ enum class E2
     e2
 };
 
+enum class E3;
+
 #endif
 
 struct Ch
@@ -115,12 +121,14 @@ int main()
 
     TEST(A);
     TEST(B);
+    TEST(C);
 
     TEST(E1);
 
 #if !defined(BOOST_NO_CXX11_SCOPED_ENUMS)
 
     TEST(E2);
+    TEST(E3);
 
 #endif
 
@@ -131,6 +139,10 @@ int main()
     TEST(B&);
     TEST(B const&);
 
+    TEST(C volatile);
+    TEST(C&);
+    TEST(C const&);
+
 #if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
 
     TEST(B&&);
@@ -141,6 +153,9 @@ int main()
     TEST(A*);
     TEST(B const* volatile*);
 
+    TEST(C*);
+    TEST(C const* volatile*);
+
     TEST(void*);
     TEST(void const* volatile*);
 
@@ -239,9 +254,18 @@ int main()
     TEST(B(&)[1][2][3]);
     TEST(B const volatile(***)[1][2][3]);
 
+#if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES) || !defined(BOOST_MSVC)
+
     TEST(int A::*);
     TEST(int const B::*);
 
+#else
+
+    boost::core::type_name<int A::*>();
+    boost::core::type_name<int const B::*>();
+
+#endif
+
 #if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES)
 
     TEST(void(A::*)());
@@ -249,6 +273,13 @@ int main()
     TEST(void(A::*)() volatile);
     TEST(void(A::*)() const volatile);
 
+#else
+
+    boost::core::type_name<void(A::*)()>();
+    boost::core::type_name<void(A::*)() const>();
+    boost::core::type_name<void(A::*)() volatile>();
+    boost::core::type_name<void(A::*)() const volatile>();
+
 #endif
 
 #if !defined(BOOST_NO_CXX11_REF_QUALIFIERS)
@@ -274,6 +305,8 @@ int main()
     TEST(std::pair<A, B>);
     TEST(std::pair<A const*, B*> volatile&);
 
+    TEST(std::pair<C, C>);
+
     TEST(std::pair<void, void>);
     TEST(std::pair<std::pair<void, void>, void>);
 
@@ -298,6 +331,11 @@ int main()
     TEST(X<A, B>);
     TEST(X<A const&, B&> volatile&);
 
+    TEST(X<C, C>);
+
+    TEST(Y<A, B>);
+    TEST(Y<C, C>);
+
     TEST(X<std::pair<void, void>, void>);
 
     TEST(std::vector<int>);