Update documentation

.drone.jsonnet

@@ -135,55 +135,230 @@ local windows_pipeline(name, image, environment, arch = "amd64") =
     ),
 
     linux_pipeline(
-        "Linux 20.04 GCC 9 ARM64",
+        "Linux 16.04 GCC 5* 32/64",
+        "cppalliance/droneubuntu1604:1",
+        { TOOLSET: 'gcc', COMPILER: 'g++', CXXSTD: '03,11,14', ADDRMD: '32,64' },
+    ),
+
+    linux_pipeline(
+        "Linux 18.04 GCC 6 32/64",
+        "cppalliance/droneubuntu1804:1",
+        { TOOLSET: 'gcc', COMPILER: 'g++-6', CXXSTD: '03,11,14', ADDRMD: '32,64' },
+        "g++-6-multilib",
+    ),
+
+    linux_pipeline(
+        "Linux 18.04 GCC 7* 32/64",
+        "cppalliance/droneubuntu1804:1",
+        { TOOLSET: 'gcc', COMPILER: 'g++', CXXSTD: '03,11,14,17', ADDRMD: '32,64' },
+    ),
+
+    linux_pipeline(
+        "Linux 18.04 GCC 8 32/64",
+        "cppalliance/droneubuntu1804:1",
+        { TOOLSET: 'gcc', COMPILER: 'g++-8', CXXSTD: '03,11,14,17', ADDRMD: '32,64' },
+        "g++-8-multilib",
+    ),
+
+    linux_pipeline(
+        "Linux 20.04 GCC 9* 32/64",
+        "cppalliance/droneubuntu2004:1",
+        { TOOLSET: 'gcc', COMPILER: 'g++', CXXSTD: '03,11,14,17,2a', ADDRMD: '32,64' },
+    ),
+
+    linux_pipeline(
+        "Linux 20.04 GCC 9* ARM64",
         "cppalliance/droneubuntu2004:multiarch",
         { TOOLSET: 'gcc', COMPILER: 'g++', CXXSTD: '03,11,14,17,2a' },
         arch="arm64",
     ),
 
     linux_pipeline(
-        "Linux 20.04 GCC 9 S390x",
+        "Linux 20.04 GCC 9* S390x",
         "cppalliance/droneubuntu2004:multiarch",
         { TOOLSET: 'gcc', COMPILER: 'g++', CXXSTD: '03,11,14,17,2a' },
         arch="s390x",
     ),
 
+    linux_pipeline(
+        "Linux 20.04 GCC 10 32/64",
+        "cppalliance/droneubuntu2004:1",
+        { TOOLSET: 'gcc', COMPILER: 'g++-10', CXXSTD: '03,11,14,17,20', ADDRMD: '32,64' },
+        "g++-10-multilib",
+    ),
+
+    linux_pipeline(
+        "Linux 22.04 GCC 11* 32/64",
+        "cppalliance/droneubuntu2204:1",
+        { TOOLSET: 'gcc', COMPILER: 'g++', CXXSTD: '03,11,14,17,2a', ADDRMD: '32,64' },
+    ),
+
     linux_pipeline(
         "Linux 22.04 GCC 12 32 ASAN",
         "cppalliance/droneubuntu2204:1",
-        { TOOLSET: 'gcc', COMPILER: 'g++-12', CXXSTD: '03,11,14,17,20', ADDRMD: '32' } + asan,
+        { TOOLSET: 'gcc', COMPILER: 'g++-12', CXXSTD: '03,11,14,17,20,2b', ADDRMD: '32' } + asan,
         "g++-12-multilib",
     ),
 
     linux_pipeline(
         "Linux 22.04 GCC 12 64 ASAN",
         "cppalliance/droneubuntu2204:1",
-        { TOOLSET: 'gcc', COMPILER: 'g++-12', CXXSTD: '03,11,14,17,20', ADDRMD: '64' } + asan,
+        { TOOLSET: 'gcc', COMPILER: 'g++-12', CXXSTD: '03,11,14,17,20,2b', ADDRMD: '64' } + asan,
         "g++-12-multilib",
     ),
 
     linux_pipeline(
-        "Linux 22.04 Clang 14 UBSAN",
+        "Linux 16.04 Clang 3.5",
+        "cppalliance/droneubuntu1604:1",
+        { TOOLSET: 'clang', COMPILER: 'clang++-3.5', CXXSTD: '03,11' },
+        "clang-3.5",
+    ),
+
+    linux_pipeline(
+        "Linux 16.04 Clang 3.6",
+        "cppalliance/droneubuntu1604:1",
+        { TOOLSET: 'clang', COMPILER: 'clang++-3.6', CXXSTD: '03,11,14' },
+        "clang-3.6",
+    ),
+
+    linux_pipeline(
+        "Linux 16.04 Clang 3.7",
+        "cppalliance/droneubuntu1604:1",
+        { TOOLSET: 'clang', COMPILER: 'clang++-3.7', CXXSTD: '03,11,14' },
+        "clang-3.7",
+    ),
+
+    linux_pipeline(
+        "Linux 16.04 Clang 3.8",
+        "cppalliance/droneubuntu1604:1",
+        { TOOLSET: 'clang', COMPILER: 'clang++-3.8', CXXSTD: '03,11,14' },
+        "clang-3.8",
+    ),
+
+    linux_pipeline(
+        "Linux 18.04 Clang 3.9",
+        "cppalliance/droneubuntu1804:1",
+        { TOOLSET: 'clang', COMPILER: 'clang++-3.9', CXXSTD: '03,11,14' },
+        "clang-3.9",
+    ),
+
+    linux_pipeline(
+        "Linux 18.04 Clang 4.0",
+        "cppalliance/droneubuntu1804:1",
+        { TOOLSET: 'clang', COMPILER: 'clang++-4.0', CXXSTD: '03,11,14' },
+        "clang-4.0",
+    ),
+
+    linux_pipeline(
+        "Linux 18.04 Clang 5.0",
+        "cppalliance/droneubuntu1804:1",
+        { TOOLSET: 'clang', COMPILER: 'clang++-5.0', CXXSTD: '03,11,14,1z' },
+        "clang-5.0",
+    ),
+
+    linux_pipeline(
+        "Linux 18.04 Clang 6.0",
+        "cppalliance/droneubuntu1804:1",
+        { TOOLSET: 'clang', COMPILER: 'clang++-6.0', CXXSTD: '03,11,14,17' },
+        "clang-6.0",
+    ),
+
+    linux_pipeline(
+        "Linux 20.04 Clang 7",
+        "cppalliance/droneubuntu2004:1",
+        { TOOLSET: 'clang', COMPILER: 'clang++-7', CXXSTD: '03,11,14,17' },
+        "clang-7",
+    ),
+
+    linux_pipeline(
+        "Linux 20.04 Clang 8",
+        "cppalliance/droneubuntu2004:1",
+        { TOOLSET: 'clang', COMPILER: 'clang++-8', CXXSTD: '03,11,14,17' },
+        "clang-8",
+    ),
+
+    linux_pipeline(
+        "Linux 20.04 Clang 9",
+        "cppalliance/droneubuntu2004:1",
+        { TOOLSET: 'clang', COMPILER: 'clang++-9', CXXSTD: '03,11,14,17,2a' },
+        "clang-9",
+    ),
+
+    linux_pipeline(
+        "Linux 20.04 Clang 10",
+        "cppalliance/droneubuntu2004:1",
+        { TOOLSET: 'clang', COMPILER: 'clang++-10', CXXSTD: '03,11,14,17,2a' },
+        "clang-10",
+    ),
+
+    linux_pipeline(
+        "Linux 20.04 Clang 11",
+        "cppalliance/droneubuntu2004:1",
+        { TOOLSET: 'clang', COMPILER: 'clang++-11', CXXSTD: '03,11,14,17,2a' },
+        "clang-11",
+    ),
+
+    linux_pipeline(
+        "Linux 20.04 Clang 12",
+        "cppalliance/droneubuntu2004:1",
+        { TOOLSET: 'clang', COMPILER: 'clang++-12', CXXSTD: '03,11,14,17,2a' },
+        "clang-12",
+    ),
+
+    linux_pipeline(
+        "Linux 22.04 Clang 13",
         "cppalliance/droneubuntu2204:1",
-        { TOOLSET: 'clang', COMPILER: 'clang++-14', CXXSTD: '03,11,14,17,20' } + ubsan,
+        { TOOLSET: 'clang', COMPILER: 'clang++-13', CXXSTD: '03,11,14,17,20,2b' },
+        "clang-13",
+    ),
+
+    linux_pipeline(
+        "Linux 22.04 Clang 14",
+        "cppalliance/droneubuntu2204:1",
+        { TOOLSET: 'clang', COMPILER: 'clang++-14', CXXSTD: '03,11,14,17,20,2b' },
         "clang-14",
     ),
 
     linux_pipeline(
-        "Linux 22.04 Clang 14 ASAN",
+        "Linux 22.04 Clang 15 UBSAN",
         "cppalliance/droneubuntu2204:1",
-        { TOOLSET: 'clang', COMPILER: 'clang++-14', CXXSTD: '03,11,14,17,20' } + asan,
-        "clang-14",
+        { TOOLSET: 'clang', COMPILER: 'clang++-15', CXXSTD: '03,11,14,17,20,2b' } + ubsan,
+        "clang-15",
+    ),
+
+    linux_pipeline(
+        "Linux 22.04 Clang 15 ASAN",
+        "cppalliance/droneubuntu2204:1",
+        { TOOLSET: 'clang', COMPILER: 'clang++-15', CXXSTD: '03,11,14,17,20,2b' } + asan,
+        "clang-15",
     ),
 
     macos_pipeline(
         "MacOS 10.15 Xcode 12.2 UBSAN",
-        { TOOLSET: 'clang', COMPILER: 'clang++', CXXSTD: '03,11,14,1z' } + ubsan,
+        { TOOLSET: 'clang', COMPILER: 'clang++', CXXSTD: '03,11,14,17,2a' } + ubsan,
     ),
 
     macos_pipeline(
         "MacOS 10.15 Xcode 12.2 ASAN",
-        { TOOLSET: 'clang', COMPILER: 'clang++', CXXSTD: '03,11,14,1z' } + asan,
+        { TOOLSET: 'clang', COMPILER: 'clang++', CXXSTD: '03,11,14,17,2a' } + 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' },
     ),
 
     windows_pipeline(
@@ -191,4 +366,16 @@ local windows_pipeline(name, image, environment, arch = "amd64") =
         "cppalliance/dronevs2017",
         { TOOLSET: 'msvc-14.1', CXXSTD: '14,17,latest' },
     ),
+
+    windows_pipeline(
+        "Windows VS2019 msvc-14.2",
+        "cppalliance/dronevs2019",
+        { TOOLSET: 'msvc-14.2', CXXSTD: '14,17,20,latest' },
+    ),
+
+    windows_pipeline(
+        "Windows VS2022 msvc-14.3",
+        "cppalliance/dronevs2022:1",
+        { TOOLSET: 'msvc-14.3', CXXSTD: '14,17,20,latest' },
+    ),
 ]

.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

@@ -19,27 +19,30 @@ jobs:
         include:
           - toolset: gcc-4.8
             cxxstd: "03,11"
-            os: ubuntu-18.04
+            os: ubuntu-latest
+            container: ubuntu:18.04
             install: g++-4.8-multilib
             address-model: 32,64
           - toolset: gcc-5
             cxxstd: "03,11,14,1z"
-            os: ubuntu-18.04
+            os: ubuntu-latest
+            container: ubuntu:18.04
             install: g++-5-multilib
             address-model: 32,64
           - toolset: gcc-6
             cxxstd: "03,11,14,1z"
-            os: ubuntu-18.04
+            os: ubuntu-latest
+            container: ubuntu:18.04
             install: g++-6-multilib
             address-model: 32,64
           - toolset: gcc-7
             cxxstd: "03,11,14,17"
-            os: ubuntu-18.04
+            os: ubuntu-20.04
             install: g++-7-multilib
             address-model: 32,64
           - toolset: gcc-8
             cxxstd: "03,11,14,17,2a"
-            os: ubuntu-18.04
+            os: ubuntu-20.04
             install: g++-8-multilib
             address-model: 32,64
           - toolset: gcc-9
@@ -58,34 +61,37 @@ jobs:
             install: g++-11-multilib
             address-model: 32,64
           - toolset: gcc-12
-            cxxstd: "03,11,14,17,20"
+            cxxstd: "03,11,14,17,20,2b"
             os: ubuntu-22.04
             install: g++-12-multilib
             address-model: 32,64
           - toolset: clang
             compiler: clang++-3.9
             cxxstd: "03,11,14"
-            os: ubuntu-18.04
+            os: ubuntu-latest
+            container: ubuntu:18.04
             install: clang-3.9
           - toolset: clang
             compiler: clang++-4.0
             cxxstd: "03,11,14"
-            os: ubuntu-18.04
+            os: ubuntu-latest
+            container: ubuntu:18.04
             install: clang-4.0
           - toolset: clang
             compiler: clang++-5.0
             cxxstd: "03,11,14,1z"
-            os: ubuntu-18.04
+            os: ubuntu-latest
+            container: ubuntu:18.04
             install: clang-5.0
           - toolset: clang
             compiler: clang++-6.0
             cxxstd: "03,11,14,17"
-            os: ubuntu-18.04
+            os: ubuntu-20.04
             install: clang-6.0
           - toolset: clang
             compiler: clang++-7
             cxxstd: "03,11,14,17"
-            os: ubuntu-18.04
+            os: ubuntu-20.04
             install: clang-7
           - toolset: clang
             compiler: clang++-8
@@ -111,26 +117,45 @@ jobs:
             os: ubuntu-20.04
           - toolset: clang
             compiler: clang++-13
-            cxxstd: "03,11,14,17,20"
+            cxxstd: "03,11,14,17,20,2b"
             os: ubuntu-22.04
             install: clang-13
           - toolset: clang
             compiler: clang++-14
-            cxxstd: "03,11,14,17,20"
+            cxxstd: "03,11,14,17,20,2b"
             os: ubuntu-22.04
             install: clang-14
+          - toolset: clang
+            compiler: clang++-15
+            cxxstd: "03,11,14,17,20,2b"
+            os: ubuntu-22.04
+            install: clang-15
           - toolset: clang
             cxxstd: "03,11,14,17,2a"
             os: macos-11
+          - toolset: clang
+            cxxstd: "03,11,14,17,20,2b"
+            os: macos-12
 
     runs-on: ${{matrix.os}}
+    container: ${{matrix.container}}
+
+    defaults:
+      run:
+        shell: bash
 
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
+
+      - name: Setup container environment
+        if: matrix.container
+        run: |
+          apt-get update
+          apt-get -y install sudo python git g++
 
       - name: Install packages
         if: matrix.install
-        run: sudo apt install ${{matrix.install}}
+        run: sudo apt-get -y install ${{matrix.install}}
 
       - name: Setup Boost
         run: |
@@ -195,7 +220,7 @@ jobs:
     runs-on: ${{matrix.os}}
 
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
 
       - name: Setup Boost
         shell: cmd
@@ -231,19 +256,19 @@ jobs:
       fail-fast: false
       matrix:
         include:
-          - os: ubuntu-18.04
           - os: ubuntu-20.04
           - os: ubuntu-22.04
           - os: macos-11
+          - os: macos-12
 
     runs-on: ${{matrix.os}}
 
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
 
       - name: Install packages
         if: matrix.install
-        run: sudo apt install ${{matrix.install}}
+        run: sudo apt-get -y install ${{matrix.install}}
 
       - name: Setup Boost
         run: |
@@ -278,19 +303,19 @@ jobs:
       fail-fast: false
       matrix:
         include:
-          - os: ubuntu-18.04
           - os: ubuntu-20.04
           - os: ubuntu-22.04
           - os: macos-11
+          - os: macos-12
 
     runs-on: ${{matrix.os}}
 
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
 
       - name: Install packages
         if: matrix.install
-        run: sudo apt install ${{matrix.install}}
+        run: sudo apt-get -y install ${{matrix.install}}
 
       - name: Setup Boost
         run: |
@@ -335,19 +360,19 @@ jobs:
       fail-fast: false
       matrix:
         include:
-          - os: ubuntu-18.04
           - os: ubuntu-20.04
           - os: ubuntu-22.04
           - os: macos-11
+          - os: macos-12
 
     runs-on: ${{matrix.os}}
 
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
 
       - name: Install packages
         if: matrix.install
-        run: sudo apt install ${{matrix.install}}
+        run: sudo apt-get -y install ${{matrix.install}}
 
       - name: Setup Boost
         run: |

CMakeLists.txt

@@ -15,6 +15,8 @@ target_include_directories(boost_container_hash INTERFACE include)
 target_link_libraries(boost_container_hash
   INTERFACE
     Boost::config
+    Boost::describe
+    Boost::mp11
     Boost::type_traits
 )
 

README.md

@@ -0,0 +1,20 @@
+# Boost.ContainerHash
+
+The Boost.ContainerHash library, part of [Boost C++ Libraries](https://boost.org),
+provides `boost::hash`, an enhanced implementation of the
+[hash function](https://en.wikipedia.org/wiki/Hash_function) object specified
+by C++11 as `std::hash`, and several support facilities (`hash_combine`,
+`hash_range`, `hash_unordered_range`).
+
+`boost::hash` supports most standard types and some user-defined types out of
+the box, and is extensible; it's possible for a user-defined type `X` to make
+iself hashable via `boost::hash<X>` by defining an appropriate overload of the
+function `hash_value`.
+
+See [the documentation of the library](https://www.boost.org/libs/container_hash)
+for more information.
+
+## License
+
+Distributed under the
+[Boost Software License, Version 1.0](http://boost.org/LICENSE_1_0.txt).

benchmark/.gitignore

@@ -0,0 +1,4 @@
+enwik8
+enwik9
+*.exe
+*.obj

benchmark/unordered.cpp

@@ -3,12 +3,22 @@
 // https://www.boost.org/LICENSE_1_0.txt
 
 #define _CRT_SECURE_NO_WARNINGS
+#define _SILENCE_CXX20_CISO646_REMOVED_WARNING
 
 #include <boost/container_hash/hash.hpp>
 #include <boost/unordered_set.hpp>
 #include <boost/core/detail/splitmix64.hpp>
 #include <boost/core/type_name.hpp>
 #include <boost/config.hpp>
+#ifdef HAVE_ABSEIL
+# include "absl/hash/hash.h"
+#endif
+#ifdef HAVE_ANKERL_UNORDERED_DENSE
+# include "ankerl/unordered_dense.h"
+#endif
+#ifdef HAVE_MULXP_HASH
+# include "mulxp_hash.hpp"
+#endif
 #include <cstddef>
 #include <cstdio>
 #include <cstdint>
@@ -19,10 +29,8 @@
 
 // mul31_hash
 
-class mul31_hash
+struct mul31_hash
 {
-public:
-
     std::size_t operator()( std::string const& st ) const BOOST_NOEXCEPT
     {
         char const * p = st.data();
@@ -43,18 +51,20 @@ public:
     }
 };
 
-// mul31_unrolled_hash
+// mul31_x4_hash
 
-template<int Bits> struct mul31_unrolled_hash_impl;
-
-template<> struct mul31_unrolled_hash_impl<32>
+struct mul31_x4_hash
 {
     std::size_t operator()( std::string const& st ) const BOOST_NOEXCEPT
     {
         char const * p = st.data();
         std::size_t n = st.size();
 
+#if SIZE_MAX > UINT32_MAX
+        std::size_t h = 0xCBF29CE484222325ull;
+#else
         std::size_t h = 0x811C9DC5u;
+#endif
 
         while( n >= 4 )
         {
@@ -80,14 +90,20 @@ template<> struct mul31_unrolled_hash_impl<32>
     }
 };
 
-template<> struct mul31_unrolled_hash_impl<64>
+// mul31_x8_hash
+
+struct mul31_x8_hash
 {
     std::size_t operator()( std::string const& st ) const BOOST_NOEXCEPT
     {
         char const * p = st.data();
         std::size_t n = st.size();
 
-        std::size_t h = 0xCBF29CE484222325ull;
+#if SIZE_MAX > UINT32_MAX
+        boost::uint64_t h = 0xCBF29CE484222325ull;
+#else
+        boost::uint64_t h = 0x811C9DC5u;
+#endif
 
         while( n >= 8 )
         {
@@ -113,12 +129,10 @@ template<> struct mul31_unrolled_hash_impl<64>
             --n;
         }
 
-        return h;
+        return static_cast<std::size_t>( h );
     }
 };
 
-struct mul31_unrolled_hash: mul31_unrolled_hash_impl< std::numeric_limits<std::size_t>::digits > {};
-
 // fnv1a_hash
 
 template<int Bits> struct fnv1a_hash_impl;
@@ -163,28 +177,44 @@ template<> struct fnv1a_hash_impl<64>
 
 struct fnv1a_hash: fnv1a_hash_impl< std::numeric_limits<std::size_t>::digits > {};
 
-// old_boost_hash
+// mulxp_hash
 
-class old_boost_hash
+#ifdef HAVE_MULXP_HASH
+
+struct mulxp1_hash_
 {
-public:
-
     std::size_t operator()( std::string const& st ) const BOOST_NOEXCEPT
     {
-        char const * p = st.data();
-        std::size_t n = st.size();
-
-        std::size_t h = 0;
-
-        for( std::size_t i = 0; i < n; ++i )
-        {
-            h ^= static_cast<unsigned char>( p[i] ) + 0x9e3779b9 + ( h << 6 ) + ( h >> 2 );
-        }
-
-        return h;
+        return mulxp1_hash( (unsigned char const*)st.data(), st.size(), 0 );
     }
 };
 
+struct mulxp3_hash_
+{
+    std::size_t operator()( std::string const& st ) const BOOST_NOEXCEPT
+    {
+        return mulxp3_hash( (unsigned char const*)st.data(), st.size(), 0 );
+    }
+};
+
+struct mulxp1_hash32_
+{
+    std::size_t operator()( std::string const& st ) const BOOST_NOEXCEPT
+    {
+        return mulxp1_hash32( (unsigned char const*)st.data(), st.size(), 0 );
+    }
+};
+
+struct mulxp3_hash32_
+{
+    std::size_t operator()( std::string const& st ) const BOOST_NOEXCEPT
+    {
+        return mulxp3_hash32( (unsigned char const*)st.data(), st.size(), 0 );
+    }
+};
+
+#endif
+
 // test_hash_speed
 
 template<class H, class V> void test_hash_speed( int N, V const& v )
@@ -210,11 +240,11 @@ template<class H, class V> void test_hash_speed( int N, V const& v )
 
 #if defined( _MSC_VER )
 
-    std::printf( "%25s : q=%20Iu, %lld ms\n", hash.c_str(), q, ms1 );
+    std::printf( "%57s : q=%20Iu, %lld ms\n", hash.c_str(), q, ms1 );
 
 #else
 
-    std::printf( "%25s : q=%20zu, %lld ms\n", hash.c_str(), q, ms1 );
+    std::printf( "%57s : q=%20zu, %lld ms\n", hash.c_str(), q, ms1 );
 
 #endif
 }
@@ -235,11 +265,11 @@ template<class H, class V> void test_hash_collision( int N, V const& v, std::siz
 
 #if defined( _MSC_VER )
 
-    std::printf( "%25s : c=%Iu\n", hash.c_str(), n - s.size() );
+    std::printf( "%57s : c=%Iu\n", hash.c_str(), n - s.size() );
 
 #else
 
-    std::printf( "%25s : c=%zu\n", hash.c_str(), n - s.size() );
+    std::printf( "%57s : c=%zu\n", hash.c_str(), n - s.size() );
 
 #endif
 }
@@ -292,11 +322,11 @@ template<class V, class S> void test4( int N, V const& v, char const * hash, S s
 
 #if defined( _MSC_VER )
 
-    std::printf( "%25s : n=%Iu, m=%Iu, c=%Iu, q=%Iu, %lld + %lld ms\n", hash, n, m, c, q, ms1, ms2 );
+    std::printf( "%57s : n=%Iu, m=%Iu, c=%Iu, q=%Iu, %4lld + %4lld = %4lld ms\n", hash, n, m, c, q, ms1, ms2, ms1 + ms2 );
 
 #else
 
-    std::printf( "%25s : n=%zu, m=%zu, c=%zu, q=%zu, %lld + %lld ms\n", hash, n, m, c, q, ms1, ms2 );
+    std::printf( "%57s : n=%zu, m=%zu, c=%zu, q=%zu, %4lld + %4lld = %4lld ms\n", hash, n, m, c, q, ms1, ms2, ms1 + ms2 );
 
 #endif
 }
@@ -340,11 +370,23 @@ int main()
     std::puts( "Hash speed test:\n" );
 
     test_hash_speed<mul31_hash>( N * 16, v );
-    test_hash_speed<mul31_unrolled_hash>( N * 16, v );
+    test_hash_speed<mul31_x4_hash>( N * 16, v );
+    test_hash_speed<mul31_x8_hash>( N * 16, v );
     test_hash_speed<fnv1a_hash>( N * 16, v );
-    test_hash_speed<old_boost_hash>( N * 16, v );
     test_hash_speed<boost::hash<std::string> >( N * 16, v );
     test_hash_speed<std::hash<std::string> >( N * 16, v );
+#ifdef HAVE_ABSEIL
+    test_hash_speed<absl::Hash<std::string> >( N * 16, v );
+#endif
+#ifdef HAVE_ANKERL_UNORDERED_DENSE
+    test_hash_speed<ankerl::unordered_dense::hash<std::string> >( N * 16, v );
+#endif
+#ifdef HAVE_MULXP_HASH
+    test_hash_speed<mulxp1_hash_>( N * 16, v );
+    test_hash_speed<mulxp3_hash_>( N * 16, v );
+    test_hash_speed<mulxp1_hash32_>( N * 16, v );
+    test_hash_speed<mulxp3_hash32_>( N * 16, v );
+#endif
 
     std::puts( "" );
 
@@ -365,25 +407,55 @@ int main()
         }
 
         test_hash_collision<mul31_hash>( N * 16, v, n );
-        test_hash_collision<mul31_unrolled_hash>( N * 16, v, n );
+        test_hash_collision<mul31_x4_hash>( N * 16, v, n );
+        test_hash_collision<mul31_x8_hash>( N * 16, v, n );
         test_hash_collision<fnv1a_hash>( N * 16, v, n );
-        test_hash_collision<old_boost_hash>( N * 16, v, n );
         test_hash_collision<boost::hash<std::string> >( N * 16, v, n );
         test_hash_collision<std::hash<std::string> >( N * 16, v, n );
+#ifdef HAVE_ABSEIL
+        test_hash_collision<absl::Hash<std::string> >( N * 16, v, n );
+#endif
+#ifdef HAVE_ANKERL_UNORDERED_DENSE
+        test_hash_collision<ankerl::unordered_dense::hash<std::string> >( N * 16, v, n );
+#endif
+#ifdef HAVE_MULXP_HASH
+        test_hash_collision<mulxp1_hash_>( N * 16, v, n );
+        test_hash_collision<mulxp3_hash_>( N * 16, v, n );
+        test_hash_collision<mulxp1_hash32_>( N * 16, v, n );
+        test_hash_collision<mulxp3_hash32_>( N * 16, v, n );
+#endif
     }
 
     std::puts( "" );
 
     typedef std::string K;
 
-    std::puts( "Container speed test:\n" );
+    std::puts( "Container speed test:\n---\n" );
 
     test_container_speed<K, mul31_hash>( N, v );
-    test_container_speed<K, mul31_unrolled_hash>( N, v );
+    test_container_speed<K, mul31_x4_hash>( N, v );
+    test_container_speed<K, mul31_x8_hash>( N, v );
     test_container_speed<K, fnv1a_hash>( N, v );
-    test_container_speed<K, old_boost_hash>( N, v );
     test_container_speed<K, boost::hash<std::string> >( N, v );
     test_container_speed<K, std::hash<std::string> >( N, v );
+#ifdef HAVE_ABSEIL
+    test_container_speed<K, absl::Hash<std::string> >( N, v );
+#endif
+#ifdef HAVE_ANKERL_UNORDERED_DENSE
+    test_container_speed<K, ankerl::unordered_dense::hash<std::string> >( N, v );
+#endif
+#ifdef HAVE_MULXP_HASH
+    test_container_speed<K, mulxp1_hash_>( N, v );
+    test_container_speed<K, mulxp3_hash_>( N, v );
+    test_container_speed<K, mulxp1_hash32_>( N, v );
+    test_container_speed<K, mulxp3_hash32_>( N, v );
+#endif
 
     std::puts( "" );
 }
+
+#ifdef HAVE_ABSEIL
+# include "absl/hash/internal/hash.cc"
+# include "absl/hash/internal/low_level_hash.cc"
+# include "absl/hash/internal/city.cc"
+#endif

benchmark/unordered_flat.cpp

@@ -0,0 +1,386 @@
+// Copyright 2021 Peter Dimov.
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#define _SILENCE_CXX17_OLD_ALLOCATOR_MEMBERS_DEPRECATION_WARNING
+#define _SILENCE_CXX20_CISO646_REMOVED_WARNING
+
+#include <boost/unordered/unordered_flat_map.hpp>
+#include <boost/core/detail/splitmix64.hpp>
+#include <boost/config.hpp>
+#ifdef HAVE_ABSEIL
+# include "absl/hash/hash.h"
+#endif
+#ifdef HAVE_ANKERL_UNORDERED_DENSE
+# include "ankerl/unordered_dense.h"
+#endif
+#ifdef HAVE_MULXP_HASH
+# include "mulxp_hash.hpp"
+#endif
+#include <vector>
+#include <memory>
+#include <cstdint>
+#include <iostream>
+#include <iomanip>
+#include <chrono>
+
+using namespace std::chrono_literals;
+
+static void print_time( std::chrono::steady_clock::time_point & t1, char const* label, std::uint32_t s, std::size_t size )
+{
+    auto t2 = std::chrono::steady_clock::now();
+
+    std::cout << label << ": " << ( t2 - t1 ) / 1ms << " ms (s=" << s << ", size=" << size << ")\n";
+
+    t1 = t2;
+}
+
+constexpr unsigned N = 2'000'000;
+constexpr int K = 10;
+
+static std::vector<std::string> indices1, indices2;
+
+static std::string make_index( unsigned x )
+{
+    char buffer[ 64 ];
+    std::snprintf( buffer, sizeof(buffer), "pfx_%u_sfx", x );
+
+    return buffer;
+}
+
+static std::string make_random_index( unsigned x )
+{
+    char buffer[ 64 ];
+    std::snprintf( buffer, sizeof(buffer), "pfx_%0*d_%u_sfx", x % 8 + 1, 0, x );
+
+    return buffer;
+}
+
+static void init_indices()
+{
+    indices1.reserve( N*2+1 );
+    indices1.push_back( make_index( 0 ) );
+
+    for( unsigned i = 1; i <= N*2; ++i )
+    {
+        indices1.push_back( make_index( i ) );
+    }
+
+    indices2.reserve( N*2+1 );
+    indices2.push_back( make_index( 0 ) );
+
+    {
+        boost::detail::splitmix64 rng;
+
+        for( unsigned i = 1; i <= N*2; ++i )
+        {
+            indices2.push_back( make_random_index( static_cast<std::uint32_t>( rng() ) ) );
+        }
+    }
+}
+
+template<class Map> BOOST_NOINLINE void test_insert( Map& map, std::chrono::steady_clock::time_point & t1 )
+{
+    for( unsigned i = 1; i <= N; ++i )
+    {
+        map.insert( { indices1[ i ], i } );
+    }
+
+    print_time( t1, "Consecutive insert",  0, map.size() );
+
+    for( unsigned i = 1; i <= N; ++i )
+    {
+        map.insert( { indices2[ i ], i } );
+    }
+
+    print_time( t1, "Random insert",  0, map.size() );
+
+    std::cout << std::endl;
+}
+
+template<class Map> BOOST_NOINLINE void test_lookup( Map& map, std::chrono::steady_clock::time_point & t1 )
+{
+    std::uint32_t s;
+    
+    s = 0;
+
+    for( int j = 0; j < K; ++j )
+    {
+        for( unsigned i = 1; i <= N * 2; ++i )
+        {
+            auto it = map.find( indices1[ i ] );
+            if( it != map.end() ) s += it->second;
+        }
+    }
+
+    print_time( t1, "Consecutive lookup",  s, map.size() );
+
+    s = 0;
+
+    for( int j = 0; j < K; ++j )
+    {
+        for( unsigned i = 1; i <= N * 2; ++i )
+        {
+            auto it = map.find( indices2[ i ] );
+            if( it != map.end() ) s += it->second;
+        }
+    }
+
+    print_time( t1, "Random lookup",  s, map.size() );
+
+    std::cout << std::endl;
+}
+
+template<class Map> BOOST_NOINLINE void test_iteration( Map& map, std::chrono::steady_clock::time_point & t1 )
+{
+    auto it = map.begin();
+
+    while( it != map.end() )
+    {
+        if( it->second & 1 )
+        {
+            if constexpr( std::is_void_v< decltype( map.erase( it ) ) > )
+            {
+                map.erase( it++ );
+            }
+            else
+            {
+                it = map.erase( it );
+            }
+        }
+        else
+        {
+            ++it;
+        }
+    }
+
+    print_time( t1, "Iterate and erase odd elements",  0, map.size() );
+
+    std::cout << std::endl;
+}
+
+template<class Map> BOOST_NOINLINE void test_erase( Map& map, std::chrono::steady_clock::time_point & t1 )
+{
+    for( unsigned i = 1; i <= N; ++i )
+    {
+        map.erase( indices1[ i ] );
+    }
+
+    print_time( t1, "Consecutive erase",  0, map.size() );
+
+    for( unsigned i = 1; i <= N; ++i )
+    {
+        map.erase( indices2[ i ] );
+    }
+
+    print_time( t1, "Random erase",  0, map.size() );
+
+    std::cout << std::endl;
+}
+
+//
+
+struct record
+{
+    std::string label_;
+    long long time_;
+};
+
+static std::vector<record> times;
+
+template<class Hash> BOOST_NOINLINE void test( char const* label )
+{
+    std::cout << label << ":\n\n";
+
+    boost::unordered_flat_map<std::string, std::uint32_t, Hash> map;
+
+    auto t0 = std::chrono::steady_clock::now();
+    auto t1 = t0;
+
+    test_insert( map, t1 );
+
+    record rec = { label, 0 };
+
+    test_lookup( map, t1 );
+    test_iteration( map, t1 );
+    test_lookup( map, t1 );
+    test_erase( map, t1 );
+
+    auto tN = std::chrono::steady_clock::now();
+    std::cout << "Total: " << ( tN - t0 ) / 1ms << " ms\n\n";
+
+    rec.time_ = ( tN - t0 ) / 1ms;
+    times.push_back( rec );
+}
+
+// fnv1a_hash
+
+template<int Bits> struct fnv1a_hash_impl;
+
+template<> struct fnv1a_hash_impl<32>
+{
+    std::size_t operator()( std::string const& s ) const
+    {
+        std::size_t h = 0x811C9DC5u;
+
+        char const * first = s.data();
+        char const * last = first + s.size();
+
+        for( ; first != last; ++first )
+        {
+            h ^= static_cast<unsigned char>( *first );
+            h *= 0x01000193ul;
+        }
+
+        return h;
+    }
+};
+
+template<> struct fnv1a_hash_impl<64>
+{
+    std::size_t operator()( std::string const& s ) const
+    {
+        std::size_t h = 0xCBF29CE484222325ull;
+
+        char const * first = s.data();
+        char const * last = first + s.size();
+
+        for( ; first != last; ++first )
+        {
+            h ^= static_cast<unsigned char>( *first );
+            h *= 0x00000100000001B3ull;
+        }
+
+        return h;
+    }
+};
+
+struct fnv1a_hash: fnv1a_hash_impl< std::numeric_limits<std::size_t>::digits >
+{
+    using is_avalanching = void;
+};
+
+// std_hash
+
+struct std_hash: std::hash<std::string>
+{
+    using is_avalanching = void;
+};
+
+// absl_hash
+
+#ifdef HAVE_ABSEIL
+
+struct absl_hash: absl::Hash<std::string>
+{
+    using is_avalanching = void;
+};
+
+#endif
+
+// mulxp_hash
+
+#ifdef HAVE_MULXP_HASH
+
+struct mulxp1_hash_
+{
+    using is_avalanching = void;
+
+    std::size_t operator()( std::string const& st ) const BOOST_NOEXCEPT
+    {
+        return mulxp1_hash( (unsigned char const*)st.data(), st.size(), 0 );
+    }
+};
+
+struct mulxp3_hash_
+{
+    using is_avalanching = void;
+
+    std::size_t operator()( std::string const& st ) const BOOST_NOEXCEPT
+    {
+        return mulxp3_hash( (unsigned char const*)st.data(), st.size(), 0 );
+    }
+};
+
+struct mulxp1_hash32_
+{
+    using is_avalanching = void;
+
+    std::size_t operator()( std::string const& st ) const BOOST_NOEXCEPT
+    {
+        std::size_t r = mulxp1_hash32( (unsigned char const*)st.data(), st.size(), 0 );
+
+#if SIZE_MAX > UINT32_MAX
+
+        r |= r << 32;
+
+#endif
+
+        return r;
+    }
+};
+
+struct mulxp3_hash32_
+{
+    using is_avalanching = void;
+
+    std::size_t operator()( std::string const& st ) const BOOST_NOEXCEPT
+    {
+        std::size_t r = mulxp3_hash32( (unsigned char const*)st.data(), st.size(), 0 );
+
+#if SIZE_MAX > UINT32_MAX
+
+        r |= r << 32;
+
+#endif
+
+        return r;
+    }
+};
+
+#endif
+
+//
+
+int main()
+{
+    init_indices();
+
+    test< boost::hash<std::string> >( "boost::hash" );
+    test< std_hash >( "std::hash" );
+    test< fnv1a_hash >( "fnv1a_hash" );
+
+#ifdef HAVE_ABSEIL
+
+    test< absl_hash >( "absl::Hash" );
+
+#endif
+
+#ifdef HAVE_ANKERL_UNORDERED_DENSE
+
+    test< ankerl::unordered_dense::hash<std::string> >( "ankerl::unordered_dense::hash" );
+
+#endif
+
+#ifdef HAVE_MULXP_HASH
+
+    test< mulxp1_hash_ >( "mulxp1_hash" );
+    test< mulxp3_hash_ >( "mulxp3_hash" );
+    test< mulxp1_hash32_ >( "mulxp1_hash32" );
+    test< mulxp3_hash32_ >( "mulxp3_hash32" );
+
+#endif
+
+    std::cout << "---\n\n";
+
+    for( auto const& x: times )
+    {
+        std::cout << std::setw( 32 ) << ( x.label_ + ": " ) << std::setw( 5 ) << x.time_ << " ms\n";
+    }
+}
+
+#ifdef HAVE_ABSEIL
+# include "absl/hash/internal/hash.cc"
+# include "absl/hash/internal/low_level_hash.cc"
+# include "absl/hash/internal/city.cc"
+#endif

benchmark/word_count.cpp

@@ -0,0 +1,319 @@
+// Copyright 2022 Peter Dimov.
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#define _SILENCE_CXX17_OLD_ALLOCATOR_MEMBERS_DEPRECATION_WARNING
+#define _SILENCE_CXX20_CISO646_REMOVED_WARNING
+
+#include <boost/unordered/unordered_flat_map.hpp>
+#ifdef HAVE_ABSEIL
+# include "absl/hash/hash.h"
+#endif
+#ifdef HAVE_ANKERL_UNORDERED_DENSE
+# include "ankerl/unordered_dense.h"
+#endif
+#ifdef HAVE_MULXP_HASH
+# include "mulxp_hash.hpp"
+#endif
+#include <boost/regex.hpp>
+#include <vector>
+#include <memory>
+#include <cstdint>
+#include <iostream>
+#include <iomanip>
+#include <chrono>
+#include <fstream>
+#include <string_view>
+#include <string>
+
+using namespace std::chrono_literals;
+
+static void print_time( std::chrono::steady_clock::time_point & t1, char const* label, std::uint32_t s, std::size_t size )
+{
+    auto t2 = std::chrono::steady_clock::now();
+
+    std::cout << label << ": " << ( t2 - t1 ) / 1ms << " ms (s=" << s << ", size=" << size << ")\n";
+
+    t1 = t2;
+}
+
+static std::vector<std::string> words;
+
+static void init_words()
+{
+#if SIZE_MAX > UINT32_MAX
+
+    char const* fn = "enwik9"; // http://mattmahoney.net/dc/textdata
+
+#else
+
+    char const* fn = "enwik8"; // ditto
+
+#endif
+
+    auto t1 = std::chrono::steady_clock::now();
+
+    std::ifstream is( fn );
+    std::string in( std::istreambuf_iterator<char>( is ), std::istreambuf_iterator<char>{} );
+
+    boost::regex re( "[a-zA-Z]+");
+    boost::sregex_token_iterator it( in.begin(), in.end(), re, 0 ), end;
+
+    words.assign( it, end );
+
+    auto t2 = std::chrono::steady_clock::now();
+
+    std::cout << fn << ": " << words.size() << " words, " << ( t2 - t1 ) / 1ms << " ms\n\n";
+}
+
+template<class Map> BOOST_NOINLINE void test_word_count( Map& map, std::chrono::steady_clock::time_point & t1 )
+{
+    std::size_t s = 0;
+
+    for( auto const& word: words )
+    {
+        ++map[ word ];
+        ++s;
+    }
+
+    print_time( t1, "Word count", s, map.size() );
+
+    std::cout << std::endl;
+}
+
+template<class Map> BOOST_NOINLINE void test_contains( Map& map, std::chrono::steady_clock::time_point & t1 )
+{
+    std::size_t s = 0;
+
+    for( auto const& word: words )
+    {
+        std::string_view w2( word );
+        w2.remove_prefix( 1 );
+
+        s += map.contains( w2 );
+    }
+
+    print_time( t1, "Contains", s, map.size() );
+
+    std::cout << std::endl;
+}
+
+template<class Map> BOOST_NOINLINE void test_count( Map& map, std::chrono::steady_clock::time_point & t1 )
+{
+    std::size_t s = 0;
+
+    for( auto const& word: words )
+    {
+        std::string_view w2( word );
+        w2.remove_prefix( 1 );
+
+        s += map.count( w2 );
+    }
+
+    print_time( t1, "Count", s, map.size() );
+
+    std::cout << std::endl;
+}
+
+//
+
+struct record
+{
+    std::string label_;
+    long long time_;
+};
+
+static std::vector<record> times;
+
+template<class Hash> BOOST_NOINLINE void test( char const* label )
+{
+    std::cout << label << ":\n\n";
+
+    boost::unordered_flat_map<std::string_view, std::size_t, Hash> map;
+
+    auto t0 = std::chrono::steady_clock::now();
+    auto t1 = t0;
+
+    test_word_count( map, t1 );
+
+    record rec = { label, 0 };
+
+    test_contains( map, t1 );
+    test_count( map, t1 );
+
+    auto tN = std::chrono::steady_clock::now();
+    std::cout << "Total: " << ( tN - t0 ) / 1ms << " ms\n\n";
+
+    rec.time_ = ( tN - t0 ) / 1ms;
+    times.push_back( rec );
+}
+
+// fnv1a_hash
+
+template<int Bits> struct fnv1a_hash_impl;
+
+template<> struct fnv1a_hash_impl<32>
+{
+    std::size_t operator()( std::string_view const& s ) const
+    {
+        std::size_t h = 0x811C9DC5u;
+
+        char const * first = s.data();
+        char const * last = first + s.size();
+
+        for( ; first != last; ++first )
+        {
+            h ^= static_cast<unsigned char>( *first );
+            h *= 0x01000193ul;
+        }
+
+        return h;
+    }
+};
+
+template<> struct fnv1a_hash_impl<64>
+{
+    std::size_t operator()( std::string_view const& s ) const
+    {
+        std::size_t h = 0xCBF29CE484222325ull;
+
+        char const * first = s.data();
+        char const * last = first + s.size();
+
+        for( ; first != last; ++first )
+        {
+            h ^= static_cast<unsigned char>( *first );
+            h *= 0x00000100000001B3ull;
+        }
+
+        return h;
+    }
+};
+
+struct fnv1a_hash: fnv1a_hash_impl< std::numeric_limits<std::size_t>::digits >
+{
+    using is_avalanching = void;
+};
+
+// std_hash
+
+struct std_hash: std::hash<std::string_view>
+{
+    using is_avalanching = void;
+};
+
+// absl_hash
+
+#ifdef HAVE_ABSEIL
+
+struct absl_hash: absl::Hash<std::string_view>
+{
+    using is_avalanching = void;
+};
+
+#endif
+
+#ifdef HAVE_MULXP_HASH
+
+struct mulxp1_hash_
+{
+    using is_avalanching = void;
+
+    std::size_t operator()( std::string_view const& st ) const BOOST_NOEXCEPT
+    {
+        return mulxp1_hash( (unsigned char const*)st.data(), st.size(), 0 );
+    }
+};
+
+struct mulxp3_hash_
+{
+    using is_avalanching = void;
+
+    std::size_t operator()( std::string_view const& st ) const BOOST_NOEXCEPT
+    {
+        return mulxp3_hash( (unsigned char const*)st.data(), st.size(), 0 );
+    }
+};
+
+struct mulxp3_hash32_
+{
+    using is_avalanching = void;
+
+    std::size_t operator()( std::string_view const& st ) const BOOST_NOEXCEPT
+    {
+        std::size_t r = mulxp3_hash32( (unsigned char const*)st.data(), st.size(), 0 );
+
+#if SIZE_MAX > UINT32_MAX
+
+        r |= r << 32;
+
+#endif
+
+        return r;
+    }
+};
+
+struct mulxp1_hash32_
+{
+    using is_avalanching = void;
+
+    std::size_t operator()( std::string_view const& st ) const BOOST_NOEXCEPT
+    {
+        std::size_t r = mulxp1_hash32( (unsigned char const*)st.data(), st.size(), 0 );
+
+#if SIZE_MAX > UINT32_MAX
+
+        r |= r << 32;
+
+#endif
+
+        return r;
+    }
+};
+
+#endif
+
+//
+
+int main()
+{
+    init_words();
+
+    test< boost::hash<std::string_view> >( "boost::hash" );
+    test< std_hash >( "std::hash" );
+    test< fnv1a_hash >( "fnv1a_hash" );
+
+#ifdef HAVE_ABSEIL
+
+    test< absl_hash >( "absl::Hash" );
+
+#endif
+
+#ifdef HAVE_ANKERL_UNORDERED_DENSE
+
+    test< ankerl::unordered_dense::hash<std::string_view> >( "ankerl::unordered_dense::hash" );
+
+#endif
+
+#ifdef HAVE_MULXP_HASH
+
+    test< mulxp1_hash_ >( "mulxp1_hash" );
+    test< mulxp3_hash_ >( "mulxp3_hash" );
+    test< mulxp1_hash32_ >( "mulxp1_hash32" );
+    test< mulxp3_hash32_ >( "mulxp3_hash32" );
+
+#endif
+
+    std::cout << "---\n\n";
+
+    for( auto const& x: times )
+    {
+        std::cout << std::setw( 32 ) << ( x.label_ + ": " ) << std::setw( 5 ) << x.time_ << " ms\n";
+    }
+}
+
+#ifdef HAVE_ABSEIL
+# include "absl/hash/internal/hash.cc"
+# include "absl/hash/internal/low_level_hash.cc"
+# include "absl/hash/internal/city.cc"
+#endif

doc/hash.adoc

@@ -22,6 +22,7 @@ include::hash/recent.adoc[]
 include::hash/tutorial.adoc[]
 include::hash/user.adoc[]
 include::hash/combine.adoc[]
+include::hash/describe.adoc[]
 include::hash/reference.adoc[]
 include::hash/notes.adoc[]
 include::hash/links.adoc[]

doc/hash/describe.adoc

@@ -0,0 +1,61 @@
+////
+Copyright 2022 Peter Dimov
+Distributed under the Boost Software License, Version 1.0.
+https://www.boost.org/LICENSE_1_0.txt
+////
+
+[#describe]
+= Hashing User Types with Boost.Describe
+:idprefix: describe_
+
+Let's look at our `point` class again:
+
+[source]
+----
+class point
+{
+    int x;
+    int y;
+
+public:
+
+    point() : x(0), y(0) {}
+    point(int x, int y) : x(x), y(y) {}
+};
+----
+
+If you're using {cpp}14 or above, a much easier way to add
+support for `boost::hash` to `point` is by using
+link:../../../describe/index.html[Boost.Describe] (and
+get an automatic definition of `operator==` for free):
+
+[source]
+----
+
+#include <boost/describe/class.hpp>
+#include <boost/describe/operators.hpp>
+
+class point
+{
+    int x;
+    int y;
+
+    BOOST_DESCRIBE_CLASS(point, (), (), (), (x, y))
+
+public:
+
+    point() : x(0), y(0) {}
+    point(int x, int y) : x(x), y(y) {}
+};
+
+using boost::describe::operators::operator==;
+using boost::describe::operators::operator!=;
+----
+
+(Full code for this example is at
+link:../../examples/point2.cpp[examples/point2.cpp].)
+
+Since the `point` class has been annotated with `BOOST_DESCRIBE_CLASS`,
+the library can enumerate its members (and base classes) and automatically
+synthesize the appropriate `hash_value` overload for it, without us needing
+to do so.

doc/hash/intro.adoc

@@ -22,16 +22,21 @@ Out of the box, `boost::hash` supports
 
 * standard integral types (integers, character types, and `bool`);
 * standard floating point types (`float`, `double`, `long double`);
-* pointers (to objects and to functions, but not pointers to members);
+* pointers (to objects and to functions, but not pointers to members)
+  and `nullptr`;
 * enumeration types;
 * C arrays;
 * `std::complex`;
-* `std::pair`, `std::tuple`;
+* tuple-like types, such as `std::pair`, `std::tuple`, and user-defined
+  types that specialize `std::tuple_size` and provide `get<I>`;
 * sequence-like types, both standard and user-defined (sequence-like types
   have `begin()` and `end()` member functions returning iterators);
 * unordered sequences, standard or user-defined (sequences for which the hash
   value does not depend on the element order, such as `std::unordered_set` and
   `std::unordered_map`);
+* described structs and classes -- ones that have been annotated with the
+  `BOOST_DESCRIBE_STRUCT` or `BOOST_DESCRIBE_CLASS` macros from
+  link:../../../describe/index.html[Boost.Describe];
 * `std::unique_ptr`, `std::shared_ptr`;
 * `std::type_index`;
 * `std::error_code`, `std::error_condition`;

doc/hash/notes.adoc

@@ -10,6 +10,26 @@ https://www.boost.org/LICENSE_1_0.txt
 = Design and Implementation Notes
 :idprefix: notes_
 
+== Quality of the Hash Function
+
+Many hash functions strive to have little correlation between the input and
+output values. They attempt to uniformally distribute the output values for
+very similar inputs. This hash function makes no such attempt. In fact, for
+integers, the result of the hash function is often just the input value. So
+similar but different input values will often result in similar but different
+output values. This means that it is not appropriate as a general hash
+function. For example, a hash table may discard bits from the hash function
+resulting in likely collisions, or might have poor collision resolution when
+hash values are clustered together. In such cases this hash function will
+perform poorly.
+
+But the standard has no such requirement for the hash function, it just
+requires that the hashes of two different values are unlikely to collide.
+Containers or algorithms designed to work with the standard hash function will
+have to be implemented to work well when the hash function's output is
+correlated to its input. Since they are paying that cost a higher quality hash
+function would be wasteful.
+
 == The hash_value Customization Point
 
 The way one customizes the standard `std::hash` function object for user
@@ -35,6 +55,22 @@ to be templates constrained on e.g. `std::is_integral` or its moral
 equivalent. This causes types convertible to an integral to no longer
 match, avoiding the problem.
 
+== Hash Value Stability
+
+In general, the library does not promise that the hash values will stay
+the same from release to release (otherwise improvements would be
+impossible). However, historically values have been quite stable. Before
+release 1.81, the previous changes have been in 1.56 (a better
+`hash_combine`) and 1.78 (macOS-specific change to `hash_combine`.)
+
+Code should generally not depend on specific hash values, but for those
+willing to take the risk of occasional breaks due to hash value changes,
+the library now has a test that checks hash values for a number of types
+against reference values (`test/hash_reference_values.cpp`),
+whose https://github.com/boostorg/container_hash/commits/develop/test/hash_reference_values.cpp[version history]
+can be used as a rough guide to when hash values have changed, and for what
+types.
+
 == hash_combine
 
 The initial implementation of the library was based on Issue 6.18 of the
@@ -154,22 +190,39 @@ With this improved `hash_combine`, `boost::hash` for strings now passes the
 https://github.com/aappleby/smhasher[SMHasher test suite] by Austin Appleby
 (for a 64 bit `size_t`).
 
-== Quality of the Hash Function
+== hash_range
 
-Many hash functions strive to have little correlation between the input and
-output values. They attempt to uniformally distribute the output values for
-very similar inputs. This hash function makes no such attempt. In fact, for
-integers, the result of the hash function is often just the input value. So
-similar but different input values will often result in similar but different
-output values. This means that it is not appropriate as a general hash
-function. For example, a hash table may discard bits from the hash function
-resulting in likely collisions, or might have poor collision resolution when
-hash values are clustered together. In such cases this hash function will
-perform poorly.
+The traditional implementation of `hash_range(seed, first, last)` has been
 
-But the standard has no such requirement for the hash function, it just
-requires that the hashes of two different values are unlikely to collide.
-Containers or algorithms designed to work with the standard hash function will
-have to be implemented to work well when the hash function's output is
-correlated to its input. Since they are paying that cost a higher quality hash
-function would be wasteful.
+[source]
+----
+for( ; first != last; ++first )
+{
+    boost::hash_combine<typename std::iterator_traits<It>::value_type>( seed, *first );
+}
+----
+
+(the explicit template parameter is needed to support iterators with proxy
+return types such as `std::vector<bool>::iterator`.)
+
+This is logical, consistent and straightforward. In the common case where
+`typename std::iterator_traits<It>::value_type` is `char` -- which it is
+in the common case of `boost::hash<std::string>` -- this however leaves a
+lot of performance on the table, because processing each `char` individually
+is much less efficient than processing several in bulk.
+
+In Boost 1.81, `hash_range` was changed to process elements of type `char`,
+`signed char`, `unsigned char`, `std::byte`, or `char8_t`, four of a time.
+A `uint32_t` is composed from `first[0]` to `first[3]`, and that `uint32_t`
+is fed to `hash_combine`.
+
+In Boost 1.82, `hash_range` for these types was changed to use
+https://github.com/pdimov/mulxp_hash[`mulxp1_hash`]. This improves both
+quality and speed of string hashing.
+
+Note that `hash_range` has also traditionally guaranteed that the same element
+sequence yields the same hash value regardless of the iterator type. This
+property remains valid after the changes to `char` range hashing. `hash_range`,
+applied to the `char` sequence `{ 'a', 'b', 'c' }`, results in the same value
+whether the sequence comes from `char[3]`, `std::string`, `std::deque<char>`,
+or `std::list<char>`.

doc/hash/recent.adoc

@@ -8,6 +8,17 @@ https://www.boost.org/LICENSE_1_0.txt
 = Recent Changes
 :idprefix: recent_
 
+== Boost 1.82.0
+
+* Added an overload of `hash_value` for `std::nullptr_t`.
+* Added `is_tuple_like` and an overload of `hash_value` for
+  tuple-like types.
+* Changed string hashing to use
+  https://github.com/pdimov/mulxp_hash[`mulxp1_hash`],
+  improving both quality and speed. This changes the hash values
+  for string-like types (ranges of `char`, `signed char`,
+  `unsigned char`, `std::byte`, `char8_t`).
+
 == Boost 1.81.0
 
 Major update.
@@ -21,9 +32,21 @@ Major update.
 * User-defined containers (types that have `begin()` and `end()`
   member functions that return iterators) are now supported out
   of the box.
-* `hash_combine` has been improved.
+* Described structs and classes (those annotated with
+  `BOOST_DESCRIBE_STRUCT` or `BOOST_DESCRIBE_CLASS`) are now
+  supported out of the box.
+* `hash_combine` has been improved. This changes the hash values
+  of composite (container and tuple) types and of scalar types
+  bigger than `size_t`.
 * The performance (and quality, as a result of the above change)
   of string hashing has been improved. `boost::hash` for strings
   now passes SMHasher in 64 bit mode.
 * The documentation has been substantially revised to reflect
   the changes.
+
+== Boost 1.78.0
+
+* Fixed `hash_combine` so that its behavior no longer depends
+  on whether `size_t` is the exact same type as `boost::uint64_t`
+  (which wasn't the case on macOS). This changes the hash values
+  of composite (container and tuple) types on macOS.

doc/hash/reference.adoc

@@ -29,6 +29,8 @@ namespace container_hash
 template<class T> struct is_range;
 template<class T> struct is_contiguous_range;
 template<class T> struct is_unordered_range;
+template<class T> struct is_described_class;
+template<class T> struct is_tuple_like;
 
 } // namespace container_hash
 
@@ -88,8 +90,9 @@ template<class T>
 template<class A, class B>
   std::size_t hash_value( std::pair<A, B> const& v );
 
-template<class... T>
-  std::size_t hash_value( std::tuple<T...> const& v );
+// Enabled only when container_hash::is_tuple_like<T>::value is true
+template<class T>
+  std::size_t hash_value( T const& v );
 
 // Enabled only when container_hash::is_range<T>::value is true
 template<class T>
@@ -103,6 +106,10 @@ template<class T>
 template<class T>
   std::size_t hash_value( T const& v );
 
+// Enabled only when container_hash::is_described_class<T>::value is true
+template<class T>
+  std::size_t hash_value( T const& v );
+
 template<class T>
   std::size_t hash_value( std::shared_ptr<T> const& v );
 
@@ -225,7 +232,7 @@ Effects: ::
 +
 --
 When `typename std::iterator_traits<It>::value_type` is not `char`, `signed char`,
-`unsigned char`,
+`unsigned char`, `std::byte`, or `char8_t`,
 
 [source]
 ----
@@ -235,11 +242,16 @@ for( ; first != last; ++first )
 }
 ----
 
-Otherwise, bytes from `[first, last)` are coalesced in an unspecified manner
-and then passed to `hash_combine`, more than one at a time. This is done in
-order to improve performance when hashing strings.
+Otherwise, bytes from `[first, last)` are coalesced and hashed in an
+unspecified manner. This is done in order to improve performance when hashing
+strings.
 --
 
+Remarks: ::
+  For chars, the current implementation uses
+  https://github.com/pdimov/mulxp_hash[`mulxp1_hash`] when `std::size_t` is
+  64 bit, and `mulxp1_hash32` when it's 32 bit.
+
 [source]
 ----
 template<class It> std::size_t hash_range( It first, It last );
@@ -380,8 +392,9 @@ return seed;
 
 [source]
 ----
-template<class... T>
-  std::size_t hash_value( std::tuple<T...> const& v );
+// Enabled only when container_hash::is_tuple_like<T>::value is true
+template<class T>
+  std::size_t hash_value( T const& v );
 ----
 
 Effects: ::
@@ -390,15 +403,21 @@ Effects: ::
 ----
 std::size_t seed = 0;
 
-boost::hash_combine( seed, std::get<0>(v) );
-boost::hash_combine( seed, std::get<1>(v) );
+using std::get;
+
+boost::hash_combine( seed, get<0>(v) );
+boost::hash_combine( seed, get<1>(v) );
 // ...
-boost::hash_combine( seed, std::get<N-1>(v) );
+boost::hash_combine( seed, get<N-1>(v) );
 
 return seed;
 ----
 +
-where `N` is `sizeof...(T)`.
+where `N` is `std::tuple_size<T>::value`.
+
+Remarks: ::
+This overload is only enabled when
+`container_hash::is_range<T>::value` is `false`.
 
 [source]
 ----
@@ -446,6 +465,34 @@ Remarks: ::
 This overload handles the standard unordered containers, such as
 `std::unordered_set` and `std::unordered_map`.
 
+[source]
+----
+// Enabled only when container_hash::is_described_class<T>::value is true
+template<class T>
+  std::size_t hash_value( T const& v );
+----
+
+Effects: ::
++
+[source]
+----
+std::size_t seed = 0;
+
+boost::hash_combine( seed, b1 );
+boost::hash_combine( seed, b2 );
+// ...
+boost::hash_combine( seed, bM );
+
+boost::hash_combine( seed, m1 );
+boost::hash_combine( seed, m2 );
+// ...
+boost::hash_combine( seed, mN );
+
+return seed;
+----
++
+where `bi` are the bases of `v` and `mi` are its members.
+
 [source]
 ----
 template<class T>
@@ -633,3 +680,75 @@ template<class T> struct is_unordered_range
 
 Users are allowed to specialize `is_unordered_range` for their types
 if the default behavior does not deduce the correct value.
+
+== <boost/container_hash/{zwsp}is_described_class.hpp>
+
+Defines the trait `boost::container_hash::is_described_class`.
+
+[source]
+----
+namespace boost
+{
+
+namespace container_hash
+{
+
+template<class T> struct is_described_class;
+
+} // namespace container_hash
+
+} // namespace boost
+----
+
+=== is_described_class<T>
+
+[source]
+----
+template<class T> struct is_described_class
+{
+    static constexpr bool value = /* see below */;
+};
+----
+
+`is_described_class<T>::value` is `true` when
+`boost::describe::has_describe_bases<T>::value` is `true`,
+`boost::describe::has_describe_members<T>::value` is `true`, and
+`T` is not a union.
+
+Users are allowed to specialize `is_described_class` for their types
+if the default behavior does not deduce the correct value.
+
+== <boost/container_hash/{zwsp}is_tuple_like.hpp>
+
+Defines the trait `boost::container_hash::is_tuple_like`.
+
+[source]
+----
+namespace boost
+{
+
+namespace container_hash
+{
+
+template<class T> struct is_tuple_like;
+
+} // namespace container_hash
+
+} // namespace boost
+----
+
+=== is_tuple_like<T>
+
+[source]
+----
+template<class T> struct is_tuple_like
+{
+    static constexpr bool value = /* see below */;
+};
+----
+
+`is_tuple_like<T>::value` is `true` when `std::tuple_size<T>::value`
+is valid.
+
+Users are allowed to specialize `is_tuple_like` for their types
+if the default behavior does not deduce the correct value.

doc/hash/thanks.adoc

@@ -1,6 +1,13 @@
+////
+Copyright 2005-2008 Daniel James
+Copyright 2022 Christian Mazakas
+Copyright 2022 Peter Dimov
+Distributed under the Boost Software License, Version 1.0.
+https://www.boost.org/LICENSE_1_0.txt
+////
+
 [#thanks]
 = Acknowledgements
-
 :idprefix: thanks_
 
 This library is based on the design by Peter Dimov. During the initial development Joaquín M López Muñoz made many useful suggestions and contributed fixes.
@@ -12,3 +19,5 @@ The implementation of the hash function for pointers is based on suggestions mad
 Some useful improvements to the floating point hash algorithm were suggested by Daniel Krügler.
 
 The original implementation came from Jeremy B. Maitin-Shepard's hash table library, although this is a complete rewrite.
+
+The documentation was converted from Quickbook to AsciiDoc by Christian Mazakas.

doc/hash/user.adoc

@@ -74,7 +74,7 @@ assert(books.find(knife) != books.end());
 assert(books.find(dandelion) == books.end());
 ----
 
-The full example can be found in:
+The full example can be found in
 link:../../examples/books.hpp[examples/books.hpp] and
 link:../../examples/books.cpp[examples/books.cpp].
 

examples/Jamfile.v2

@@ -7,3 +7,4 @@ run books.cpp ;
 run point.cpp ;
 run portable.cpp ;
 run template.cpp : : : <toolset>msvc-8.0:<build>no ;
+run point2.cpp ;

examples/point2.cpp

@@ -0,0 +1,65 @@
+
+// Copyright 2005 Daniel James.
+// Copyright 2022 Peter Dimov.
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+// Force use of assert.
+#if defined(NDEBUG)
+#undef NDEBUG
+#endif
+
+#include <boost/container_hash/hash.hpp>
+#include <boost/describe/class.hpp>
+#include <boost/describe/operators.hpp>
+#include <cassert>
+
+// This example illustrates how to use Boost.Describe to obtain
+// automatic boost::hash support. For full details see the hash
+// tutorial.
+
+#if defined(BOOST_DESCRIBE_CXX14)
+
+class point
+{
+    int x;
+    int y;
+
+    BOOST_DESCRIBE_CLASS(point, (), (), (), (x, y))
+
+public:
+
+    point() : x(0), y(0) {}
+    point(int x, int y) : x(x), y(y) {}
+};
+
+using boost::describe::operators::operator==;
+using boost::describe::operators::operator!=;
+
+int main()
+{
+    boost::hash<point> point_hasher;
+
+    point p1(0, 0);
+    point p2(1, 2);
+    point p3(4, 1);
+    point p4 = p1;
+
+    assert(point_hasher(p1) == point_hasher(p4));
+
+    // These tests could legally fail, but if they did it'd be a pretty bad
+    // hash function.
+    assert(point_hasher(p1) != point_hasher(p2));
+    assert(point_hasher(p1) != point_hasher(p3));
+}
+
+#else
+
+#include <cstdio>
+
+int main()
+{
+    std::puts( "This example requires C++14." );
+}
+
+#endif

include/boost/container_hash/detail/hash_range.hpp

@@ -6,13 +6,16 @@
 #define BOOST_HASH_DETAIL_HASH_RANGE_HPP
 
 #include <boost/container_hash/hash_fwd.hpp>
+#include <boost/container_hash/detail/mulx.hpp>
 #include <boost/type_traits/integral_constant.hpp>
 #include <boost/type_traits/enable_if.hpp>
 #include <boost/type_traits/is_same.hpp>
 #include <boost/cstdint.hpp>
+#include <iterator>
+#include <limits>
 #include <cstddef>
 #include <climits>
-#include <iterator>
+#include <cstring>
 
 namespace boost
 {
@@ -27,8 +30,18 @@ template<> struct is_char_type<char>: public boost::true_type {};
 template<> struct is_char_type<signed char>: public boost::true_type {};
 template<> struct is_char_type<unsigned char>: public boost::true_type {};
 
+#if defined(__cpp_char8_t) && __cpp_char8_t >= 201811L
+template<> struct is_char_type<char8_t>: public boost::true_type {};
 #endif
 
+#if defined(__cpp_lib_byte) && __cpp_lib_byte >= 201603L
+template<> struct is_char_type<std::byte>: public boost::true_type {};
+#endif
+
+#endif
+
+// generic version
+
 template<class It>
 inline typename boost::enable_if_<
     !is_char_type<typename std::iterator_traits<It>::value_type>::value,
@@ -43,120 +56,352 @@ std::size_t >::type
     return seed;
 }
 
-template<class It>
-inline typename boost::enable_if_<
-    is_char_type<typename std::iterator_traits<It>::value_type>::value &&
-    is_same<typename std::iterator_traits<It>::iterator_category, std::random_access_iterator_tag>::value,
-std::size_t>::type
-    hash_range( std::size_t seed, It first, It last )
+// specialized char[] version, 32 bit
+
+template<class It> inline boost::uint32_t read32le( It p )
 {
-    std::size_t n = static_cast<std::size_t>( last - first );
+    // clang 5+, gcc 5+ figure out this pattern and use a single mov on x86
+    // gcc on s390x and power BE even knows how to use load-reverse
 
-    for( ; n >= 4; first += 4, n -= 4 )
-    {
-        // clang 5+, gcc 5+ figure out this pattern and use a single mov on x86
-        // gcc on s390x and power BE even knows how to use load-reverse
+    boost::uint32_t w =
+        static_cast<boost::uint32_t>( static_cast<unsigned char>( p[0] ) ) |
+        static_cast<boost::uint32_t>( static_cast<unsigned char>( p[1] ) ) <<  8 |
+        static_cast<boost::uint32_t>( static_cast<unsigned char>( p[2] ) ) << 16 |
+        static_cast<boost::uint32_t>( static_cast<unsigned char>( p[3] ) ) << 24;
 
-        boost::uint32_t w =
-            static_cast<boost::uint32_t>( static_cast<unsigned char>( first[0] ) ) |
-            static_cast<boost::uint32_t>( static_cast<unsigned char>( first[1] ) ) <<  8 |
-            static_cast<boost::uint32_t>( static_cast<unsigned char>( first[2] ) ) << 16 |
-            static_cast<boost::uint32_t>( static_cast<unsigned char>( first[3] ) ) << 24;
+    return w;
+}
 
-        hash_combine( seed, w );
-    }
+#if defined(_MSC_VER) && !defined(__clang__)
 
-    {
-        // add a trailing suffix byte of 0x01 because otherwise sequences of
-        // trailing zeroes are indistinguishable from end of string
+template<class T> inline boost::uint32_t read32le( T* p )
+{
+    boost::uint32_t w;
 
-        boost::uint32_t w = 0x01u;
+    std::memcpy( &w, p, 4 );
+    return w;
+}
 
-        switch( n )
-        {
-        case 1:
+#endif
 
-            w =
-                static_cast<boost::uint32_t>( static_cast<unsigned char>( first[0] ) ) |
-                0x0100u;
-
-            break;
-
-        case 2:
-
-            w =
-                static_cast<boost::uint32_t>( static_cast<unsigned char>( first[0] ) ) |
-                static_cast<boost::uint32_t>( static_cast<unsigned char>( first[1] ) ) <<  8 |
-                0x010000u;
-
-            break;
-
-        case 3:
-
-            w =
-                static_cast<boost::uint32_t>( static_cast<unsigned char>( first[0] ) ) |
-                static_cast<boost::uint32_t>( static_cast<unsigned char>( first[1] ) ) <<  8 |
-                static_cast<boost::uint32_t>( static_cast<unsigned char>( first[2] ) ) << 16 |
-                0x01000000u;
-
-            break;
-        }
-
-        hash_combine( seed, w );
-    }
-
-    return seed;
+inline boost::uint64_t mul32( boost::uint32_t x, boost::uint32_t y )
+{
+    return static_cast<boost::uint64_t>( x ) * y;
 }
 
 template<class It>
 inline typename boost::enable_if_<
     is_char_type<typename std::iterator_traits<It>::value_type>::value &&
-    !is_same<typename std::iterator_traits<It>::iterator_category, std::random_access_iterator_tag>::value,
+    is_same<typename std::iterator_traits<It>::iterator_category, std::random_access_iterator_tag>::value &&
+    std::numeric_limits<std::size_t>::digits <= 32,
 std::size_t>::type
     hash_range( std::size_t seed, It first, It last )
 {
+    It p = first;
+    std::size_t n = static_cast<std::size_t>( last - first );
+
+    boost::uint32_t const q = 0x9e3779b9U;
+    boost::uint32_t const k = 0xe35e67b1U; // q * q
+
+    boost::uint64_t h = mul32( static_cast<boost::uint32_t>( seed ) + q, k );
+    boost::uint32_t w = static_cast<boost::uint32_t>( h & 0xFFFFFFFF );
+
+    h ^= n;
+
+    while( n >= 4 )
+    {
+        boost::uint32_t v1 = read32le( p );
+
+        w += q;
+        h ^= mul32( v1 + w, k );
+
+        p += 4;
+        n -= 4;
+    }
+
+    {
+        boost::uint32_t v1 = 0;
+
+        if( n >= 1 )
+        {
+            std::size_t const x1 = ( n - 1 ) & 2; // 1: 0, 2: 0, 3: 2
+            std::size_t const x2 = n >> 1;        // 1: 0, 2: 1, 3: 1
+
+            v1 =
+                static_cast<boost::uint32_t>( static_cast<unsigned char>( p[ static_cast<std::ptrdiff_t>( x1 ) ] ) ) << x1 * 8 |
+                static_cast<boost::uint32_t>( static_cast<unsigned char>( p[ static_cast<std::ptrdiff_t>( x2 ) ] ) ) << x2 * 8 |
+                static_cast<boost::uint32_t>( static_cast<unsigned char>( p[ 0 ] ) );
+        }
+
+        w += q;
+        h ^= mul32( v1 + w, k );
+    }
+
+    w += q;
+    h ^= mul32( static_cast<boost::uint32_t>( h & 0xFFFFFFFF ) + w, static_cast<boost::uint32_t>( h >> 32 ) + w + k );
+
+    return static_cast<boost::uint32_t>( h & 0xFFFFFFFF ) ^ static_cast<boost::uint32_t>( h >> 32 );
+}
+
+template<class It>
+inline typename boost::enable_if_<
+    is_char_type<typename std::iterator_traits<It>::value_type>::value &&
+    !is_same<typename std::iterator_traits<It>::iterator_category, std::random_access_iterator_tag>::value &&
+    std::numeric_limits<std::size_t>::digits <= 32,
+std::size_t>::type
+    hash_range( std::size_t seed, It first, It last )
+{
+    std::size_t n = 0;
+
+    boost::uint32_t const q = 0x9e3779b9U;
+    boost::uint32_t const k = 0xe35e67b1U; // q * q
+
+    boost::uint64_t h = mul32( static_cast<boost::uint32_t>( seed ) + q, k );
+    boost::uint32_t w = static_cast<boost::uint32_t>( h & 0xFFFFFFFF );
+
+    boost::uint32_t v1 = 0;
+
     for( ;; )
     {
-        boost::uint32_t w = 0;
+        v1 = 0;
 
         if( first == last )
         {
-            hash_combine( seed, w | 0x01u );
-            return seed;
+            break;
         }
 
-        w |= static_cast<boost::uint32_t>( static_cast<unsigned char>( *first ) );
+        v1 |= static_cast<boost::uint32_t>( static_cast<unsigned char>( *first ) );
         ++first;
+        ++n;
 
         if( first == last )
         {
-            hash_combine( seed, w | 0x0100u );
-            return seed;
+            break;
         }
 
-        w |= static_cast<boost::uint32_t>( static_cast<unsigned char>( *first ) ) << 8;
+        v1 |= static_cast<boost::uint32_t>( static_cast<unsigned char>( *first ) ) << 8;
         ++first;
+        ++n;
 
         if( first == last )
         {
-            hash_combine( seed, w | 0x010000u );
-            return seed;
+            break;
         }
 
-        w |= static_cast<boost::uint32_t>( static_cast<unsigned char>( *first ) ) << 16;
+        v1 |= static_cast<boost::uint32_t>( static_cast<unsigned char>( *first ) ) << 16;
         ++first;
+        ++n;
 
         if( first == last )
         {
-            hash_combine( seed, w | 0x01000000u );
-            return seed;
+            break;
         }
 
-        w |= static_cast<boost::uint32_t>( static_cast<unsigned char>( *first ) ) << 24;
+        v1 |= static_cast<boost::uint32_t>( static_cast<unsigned char>( *first ) ) << 24;
         ++first;
+        ++n;
 
-        hash_combine( seed, w );
+        w += q;
+        h ^= mul32( v1 + w, k );
     }
+
+    h ^= n;
+
+    w += q;
+    h ^= mul32( v1 + w, k );
+
+    w += q;
+    h ^= mul32( static_cast<boost::uint32_t>( h & 0xFFFFFFFF ) + w, static_cast<boost::uint32_t>( h >> 32 ) + w + k );
+
+    return static_cast<boost::uint32_t>( h & 0xFFFFFFFF ) ^ static_cast<boost::uint32_t>( h >> 32 );
+}
+
+// specialized char[] version, 64 bit
+
+template<class It> inline boost::uint64_t read64le( It p )
+{
+    boost::uint64_t w =
+        static_cast<boost::uint64_t>( static_cast<unsigned char>( p[0] ) ) |
+        static_cast<boost::uint64_t>( static_cast<unsigned char>( p[1] ) ) <<  8 |
+        static_cast<boost::uint64_t>( static_cast<unsigned char>( p[2] ) ) << 16 |
+        static_cast<boost::uint64_t>( static_cast<unsigned char>( p[3] ) ) << 24 |
+        static_cast<boost::uint64_t>( static_cast<unsigned char>( p[4] ) ) << 32 |
+        static_cast<boost::uint64_t>( static_cast<unsigned char>( p[5] ) ) << 40 |
+        static_cast<boost::uint64_t>( static_cast<unsigned char>( p[6] ) ) << 48 |
+        static_cast<boost::uint64_t>( static_cast<unsigned char>( p[7] ) ) << 56;
+
+    return w;
+}
+
+#if defined(_MSC_VER) && !defined(__clang__)
+
+template<class T> inline boost::uint64_t read64le( T* p )
+{
+    boost::uint64_t w;
+
+    std::memcpy( &w, p, 8 );
+    return w;
+}
+
+#endif
+
+template<class It>
+inline typename boost::enable_if_<
+    is_char_type<typename std::iterator_traits<It>::value_type>::value &&
+    is_same<typename std::iterator_traits<It>::iterator_category, std::random_access_iterator_tag>::value &&
+    (std::numeric_limits<std::size_t>::digits > 32),
+std::size_t>::type
+    hash_range( std::size_t seed, It first, It last )
+{
+    It p = first;
+    std::size_t n = static_cast<std::size_t>( last - first );
+
+    boost::uint64_t const q = static_cast<boost::uint64_t>( 0x9e3779b9 ) << 32 | 0x7f4a7c15;
+    boost::uint64_t const k = static_cast<boost::uint64_t>( 0xdf442d22 ) << 32 | 0xce4859b9; // q * q
+
+    boost::uint64_t w = mulx( seed + q, k );
+    boost::uint64_t h = w ^ n;
+
+    while( n >= 8 )
+    {
+        boost::uint64_t v1 = read64le( p );
+
+        w += q;
+        h ^= mulx( v1 + w, k );
+
+        p += 8;
+        n -= 8;
+    }
+
+    {
+        boost::uint64_t v1 = 0;
+
+        if( n >= 4 )
+        {
+            v1 = static_cast<boost::uint64_t>( read32le( p + static_cast<std::ptrdiff_t>( n - 4 ) ) ) << ( n - 4 ) * 8 | read32le( p );
+        }
+        else if( n >= 1 )
+        {
+            std::size_t const x1 = ( n - 1 ) & 2; // 1: 0, 2: 0, 3: 2
+            std::size_t const x2 = n >> 1;        // 1: 0, 2: 1, 3: 1
+
+            v1 =
+                static_cast<boost::uint64_t>( static_cast<unsigned char>( p[ static_cast<std::ptrdiff_t>( x1 ) ] ) ) << x1 * 8 |
+                static_cast<boost::uint64_t>( static_cast<unsigned char>( p[ static_cast<std::ptrdiff_t>( x2 ) ] ) ) << x2 * 8 |
+                static_cast<boost::uint64_t>( static_cast<unsigned char>( p[ 0 ] ) );
+        }
+
+        w += q;
+        h ^= mulx( v1 + w, k );
+    }
+
+    return mulx( h + w, k );
+}
+
+template<class It>
+inline typename boost::enable_if_<
+    is_char_type<typename std::iterator_traits<It>::value_type>::value &&
+    !is_same<typename std::iterator_traits<It>::iterator_category, std::random_access_iterator_tag>::value &&
+    (std::numeric_limits<std::size_t>::digits > 32),
+std::size_t>::type
+    hash_range( std::size_t seed, It first, It last )
+{
+    std::size_t n = 0;
+
+    boost::uint64_t const q = static_cast<boost::uint64_t>( 0x9e3779b9 ) << 32 | 0x7f4a7c15;
+    boost::uint64_t const k = static_cast<boost::uint64_t>( 0xdf442d22 ) << 32 | 0xce4859b9; // q * q
+
+    boost::uint64_t w = mulx( seed + q, k );
+    boost::uint64_t h = w;
+
+    boost::uint64_t v1 = 0;
+
+    for( ;; )
+    {
+        v1 = 0;
+
+        if( first == last )
+        {
+            break;
+        }
+
+        v1 |= static_cast<boost::uint64_t>( static_cast<unsigned char>( *first ) );
+        ++first;
+        ++n;
+
+        if( first == last )
+        {
+            break;
+        }
+
+        v1 |= static_cast<boost::uint64_t>( static_cast<unsigned char>( *first ) ) << 8;
+        ++first;
+        ++n;
+
+        if( first == last )
+        {
+            break;
+        }
+
+        v1 |= static_cast<boost::uint64_t>( static_cast<unsigned char>( *first ) ) << 16;
+        ++first;
+        ++n;
+
+        if( first == last )
+        {
+            break;
+        }
+
+        v1 |= static_cast<boost::uint64_t>( static_cast<unsigned char>( *first ) ) << 24;
+        ++first;
+        ++n;
+
+        if( first == last )
+        {
+            break;
+        }
+
+        v1 |= static_cast<boost::uint64_t>( static_cast<unsigned char>( *first ) ) << 32;
+        ++first;
+        ++n;
+
+        if( first == last )
+        {
+            break;
+        }
+
+        v1 |= static_cast<boost::uint64_t>( static_cast<unsigned char>( *first ) ) << 40;
+        ++first;
+        ++n;
+
+        if( first == last )
+        {
+            break;
+        }
+
+        v1 |= static_cast<boost::uint64_t>( static_cast<unsigned char>( *first ) ) << 48;
+        ++first;
+        ++n;
+
+        if( first == last )
+        {
+            break;
+        }
+
+        v1 |= static_cast<boost::uint64_t>( static_cast<unsigned char>( *first ) ) << 56;
+        ++first;
+        ++n;
+
+        w += q;
+        h ^= mulx( v1 + w, k );
+    }
+
+    h ^= n;
+
+    w += q;
+    h ^= mulx( v1 + w, k );
+
+    return mulx( h + w, k );
 }
 
 } // namespace hash_detail

include/boost/container_hash/detail/hash_tuple.hpp

@@ -1,133 +0,0 @@
-// Copyright 2005-2009 Daniel James.
-// Copyright 2021 Peter Dimov.
-// Distributed under the Boost Software License, Version 1.0.
-// https://www.boost.org/LICENSE_1_0.txt
-
-#ifndef BOOST_HASH_DETAIL_HASH_TUPLE_LIKE_HPP
-#define BOOST_HASH_DETAIL_HASH_TUPLE_LIKE_HPP
-
-#include <boost/container_hash/hash_fwd.hpp>
-#include <boost/type_traits/enable_if.hpp>
-#include <boost/config.hpp>
-
-#if defined(BOOST_NO_CXX11_HDR_TUPLE)
-
-// no support
-
-#else
-
-#include <tuple>
-
-namespace boost
-{
-namespace hash_detail
-{
-
-template <std::size_t I, typename T>
-inline typename boost::enable_if_<(I == std::tuple_size<T>::value),
-        void>::type
-    hash_combine_tuple(std::size_t&, T const&)
-{
-}
-
-template <std::size_t I, typename T>
-inline typename boost::enable_if_<(I < std::tuple_size<T>::value),
-        void>::type
-    hash_combine_tuple(std::size_t& seed, T const& v)
-{
-    boost::hash_combine(seed, std::get<I>(v));
-    boost::hash_detail::hash_combine_tuple<I + 1>(seed, v);
-}
-
-template <typename T>
-inline std::size_t hash_tuple(T const& v)
-{
-    std::size_t seed = 0;
-    boost::hash_detail::hash_combine_tuple<0>(seed, v);
-    return seed;
-}
-
-} // namespace hash_detail
-
-#if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES)
-
-template <typename... T>
-inline std::size_t hash_value(std::tuple<T...> const& v)
-{
-    return boost::hash_detail::hash_tuple(v);
-}
-
-#else
-
-inline std::size_t hash_value(std::tuple<> const& v)
-{
-    return boost::hash_detail::hash_tuple(v);
-}
-
-template<typename A0>
-inline std::size_t hash_value(std::tuple<A0> const& v)
-{
-    return boost::hash_detail::hash_tuple(v);
-}
-
-template<typename A0, typename A1>
-inline std::size_t hash_value(std::tuple<A0, A1> const& v)
-{
-    return boost::hash_detail::hash_tuple(v);
-}
-
-template<typename A0, typename A1, typename A2>
-inline std::size_t hash_value(std::tuple<A0, A1, A2> const& v)
-{
-    return boost::hash_detail::hash_tuple(v);
-}
-
-template<typename A0, typename A1, typename A2, typename A3>
-inline std::size_t hash_value(std::tuple<A0, A1, A2, A3> const& v)
-{
-    return boost::hash_detail::hash_tuple(v);
-}
-
-template<typename A0, typename A1, typename A2, typename A3, typename A4>
-inline std::size_t hash_value(std::tuple<A0, A1, A2, A3, A4> const& v)
-{
-    return boost::hash_detail::hash_tuple(v);
-}
-
-template<typename A0, typename A1, typename A2, typename A3, typename A4, typename A5>
-inline std::size_t hash_value(std::tuple<A0, A1, A2, A3, A4, A5> const& v)
-{
-    return boost::hash_detail::hash_tuple(v);
-}
-
-template<typename A0, typename A1, typename A2, typename A3, typename A4, typename A5, typename A6>
-inline std::size_t hash_value(std::tuple<A0, A1, A2, A3, A4, A5, A6> const& v)
-{
-    return boost::hash_detail::hash_tuple(v);
-}
-
-template<typename A0, typename A1, typename A2, typename A3, typename A4, typename A5, typename A6, typename A7>
-inline std::size_t hash_value(std::tuple<A0, A1, A2, A3, A4, A5, A6, A7> const& v)
-{
-    return boost::hash_detail::hash_tuple(v);
-}
-
-template<typename A0, typename A1, typename A2, typename A3, typename A4, typename A5, typename A6, typename A7, typename A8>
-inline std::size_t hash_value(std::tuple<A0, A1, A2, A3, A4, A5, A6, A7, A8> const& v)
-{
-    return boost::hash_detail::hash_tuple(v);
-}
-
-template<typename A0, typename A1, typename A2, typename A3, typename A4, typename A5, typename A6, typename A7, typename A8, typename A9>
-inline std::size_t hash_value(std::tuple<A0, A1, A2, A3, A4, A5, A6, A7, A8, A9> const& v)
-{
-    return boost::hash_detail::hash_tuple(v);
-}
-
-#endif // #if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES)
-
-} // namespace boost
-
-#endif // #if defined(BOOST_NO_CXX11_HDR_TUPLE)
-
-#endif // #ifndef BOOST_HASH_DETAIL_HASH_TUPLE_LIKE_HPP

include/boost/container_hash/detail/hash_tuple_like.hpp

@@ -0,0 +1,156 @@
+// Copyright 2005-2009 Daniel James.
+// Copyright 2021 Peter Dimov.
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#ifndef BOOST_HASH_DETAIL_HASH_TUPLE_LIKE_HPP
+#define BOOST_HASH_DETAIL_HASH_TUPLE_LIKE_HPP
+
+#include <boost/container_hash/hash_fwd.hpp>
+#include <boost/container_hash/is_tuple_like.hpp>
+#include <boost/container_hash/is_range.hpp>
+#include <boost/type_traits/enable_if.hpp>
+#include <boost/config.hpp>
+#include <boost/config/workaround.hpp>
+
+#if defined(BOOST_NO_CXX11_HDR_TUPLE)
+
+// no support for tuple-likes
+
+#else
+
+#include <tuple>
+
+namespace boost
+{
+namespace hash_detail
+{
+
+template <std::size_t I, typename T>
+inline
+typename boost::enable_if_<(I == std::tuple_size<T>::value), void>::type
+    hash_combine_tuple_like( std::size_t&, T const& )
+{
+}
+
+template <std::size_t I, typename T>
+inline
+typename boost::enable_if_<(I < std::tuple_size<T>::value), void>::type
+    hash_combine_tuple_like( std::size_t& seed, T const& v )
+{
+    using std::get;
+    boost::hash_combine( seed, get<I>( v ) );
+
+    boost::hash_detail::hash_combine_tuple_like<I + 1>( seed, v );
+}
+
+template <typename T>
+inline std::size_t hash_tuple_like( T const& v )
+{
+    std::size_t seed = 0;
+
+    boost::hash_detail::hash_combine_tuple_like<0>( seed, v );
+
+    return seed;
+}
+
+} // namespace hash_detail
+
+#if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES)
+
+#if !BOOST_WORKAROUND(BOOST_MSVC, <= 1800)
+
+template <class T>
+inline
+typename boost::enable_if_<
+    container_hash::is_tuple_like<T>::value && !container_hash::is_range<T>::value,
+std::size_t>::type
+    hash_value( T const& v )
+{
+    return boost::hash_detail::hash_tuple_like( v );
+}
+
+#else
+
+template <typename... T>
+inline std::size_t hash_value( std::tuple<T...> const& v )
+{
+    return boost::hash_detail::hash_tuple_like( v );
+}
+
+#endif
+
+#else
+
+inline std::size_t hash_value( std::tuple<> const& v )
+{
+    return boost::hash_detail::hash_tuple_like( v );
+}
+
+template<typename A0>
+inline std::size_t hash_value( std::tuple<A0> const& v )
+{
+    return boost::hash_detail::hash_tuple_like( v );
+}
+
+template<typename A0, typename A1>
+inline std::size_t hash_value( std::tuple<A0, A1> const& v )
+{
+    return boost::hash_detail::hash_tuple_like( v );
+}
+
+template<typename A0, typename A1, typename A2>
+inline std::size_t hash_value( std::tuple<A0, A1, A2> const& v )
+{
+    return boost::hash_detail::hash_tuple_like( v );
+}
+
+template<typename A0, typename A1, typename A2, typename A3>
+inline std::size_t hash_value( std::tuple<A0, A1, A2, A3> const& v )
+{
+    return boost::hash_detail::hash_tuple_like( v );
+}
+
+template<typename A0, typename A1, typename A2, typename A3, typename A4>
+inline std::size_t hash_value( std::tuple<A0, A1, A2, A3, A4> const& v )
+{
+    return boost::hash_detail::hash_tuple_like( v );
+}
+
+template<typename A0, typename A1, typename A2, typename A3, typename A4, typename A5>
+inline std::size_t hash_value( std::tuple<A0, A1, A2, A3, A4, A5> const& v )
+{
+    return boost::hash_detail::hash_tuple_like( v );
+}
+
+template<typename A0, typename A1, typename A2, typename A3, typename A4, typename A5, typename A6>
+inline std::size_t hash_value( std::tuple<A0, A1, A2, A3, A4, A5, A6> const& v )
+{
+    return boost::hash_detail::hash_tuple_like( v );
+}
+
+template<typename A0, typename A1, typename A2, typename A3, typename A4, typename A5, typename A6, typename A7>
+inline std::size_t hash_value( std::tuple<A0, A1, A2, A3, A4, A5, A6, A7> const& v )
+{
+    return boost::hash_detail::hash_tuple_like( v );
+}
+
+template<typename A0, typename A1, typename A2, typename A3, typename A4, typename A5, typename A6, typename A7, typename A8>
+inline std::size_t hash_value( std::tuple<A0, A1, A2, A3, A4, A5, A6, A7, A8> const& v )
+{
+    return boost::hash_detail::hash_tuple_like( v );
+}
+
+template<typename A0, typename A1, typename A2, typename A3, typename A4, typename A5, typename A6, typename A7, typename A8, typename A9>
+inline std::size_t hash_value( std::tuple<A0, A1, A2, A3, A4, A5, A6, A7, A8, A9> const& v )
+{
+    return boost::hash_detail::hash_tuple_like( v );
+}
+
+#endif // #if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES)
+
+} // namespace boost
+
+#endif // #if defined(BOOST_NO_CXX11_HDR_TUPLE)
+
+#endif // #ifndef BOOST_HASH_DETAIL_HASH_TUPLE_LIKE_HPP

include/boost/container_hash/detail/mulx.hpp

@@ -0,0 +1,79 @@
+// Copyright 2022, 2023 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#ifndef BOOST_HASH_DETAIL_MULX_HPP
+#define BOOST_HASH_DETAIL_MULX_HPP
+
+#include <boost/cstdint.hpp>
+#if defined(_MSC_VER)
+# include <intrin.h>
+#endif
+
+namespace boost
+{
+namespace hash_detail
+{
+
+#if defined(_MSC_VER) && defined(_M_X64) && !defined(__clang__)
+
+__forceinline boost::uint64_t mulx( boost::uint64_t x, boost::uint64_t y )
+{
+    boost::uint64_t r2;
+    boost::uint64_t r = _umul128( x, y, &r2 );
+    return r ^ r2;
+}
+
+#elif defined(_MSC_VER) && defined(_M_ARM64) && !defined(__clang__)
+
+__forceinline boost::uint64_t mulx( boost::uint64_t x, boost::uint64_t y )
+{
+    boost::uint64_t r = x * y;
+    boost::uint64_t r2 = __umulh( x, y );
+    return r ^ r2;
+}
+
+#elif defined(__SIZEOF_INT128__)
+
+inline boost::uint64_t mulx( boost::uint64_t x, boost::uint64_t y )
+{
+    __uint128_t r = static_cast<__uint128_t>( x ) * y;
+    return static_cast<boost::uint64_t>( r ) ^ static_cast<boost::uint64_t>( r >> 64 );
+}
+
+#else
+
+inline boost::uint64_t mulx( boost::uint64_t x, boost::uint64_t y )
+{
+    boost::uint64_t x1 = static_cast<boost::uint32_t>( x );
+    boost::uint64_t x2 = x >> 32;
+
+    boost::uint64_t y1 = static_cast<boost::uint32_t>( y );
+    boost::uint64_t y2 = y >> 32;
+
+    boost::uint64_t r3 = x2 * y2;
+
+    boost::uint64_t r2a = x1 * y2;
+
+    r3 += r2a >> 32;
+
+    boost::uint64_t r2b = x2 * y1;
+
+    r3 += r2b >> 32;
+
+    boost::uint64_t r1 = x1 * y1;
+
+    boost::uint64_t r2 = (r1 >> 32) + static_cast<boost::uint32_t>( r2a ) + static_cast<boost::uint32_t>( r2b );
+
+    r1 = (r2 << 32) + static_cast<boost::uint32_t>( r1 );
+    r3 += r2 >> 32;
+
+    return r1 ^ r3;
+}
+
+#endif
+
+} // namespace hash_detail
+} // namespace boost
+
+#endif // #ifndef BOOST_HASH_DETAIL_MULX_HPP

include/boost/container_hash/detail/requires_cxx11.hpp

@@ -0,0 +1,22 @@
+#ifndef BOOST_HASH_DETAIL_REQUIRES_CXX11_HPP_INCLUDED
+#define BOOST_HASH_DETAIL_REQUIRES_CXX11_HPP_INCLUDED
+
+// 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_CXX11_VARIADIC_TEMPLATES) || \
+    defined(BOOST_NO_CXX11_RVALUE_REFERENCES) || \
+    defined(BOOST_NO_CXX11_DECLTYPE) || \
+    defined(BOOST_NO_CXX11_CONSTEXPR) || \
+    defined(BOOST_NO_CXX11_NOEXCEPT) || \
+    defined(BOOST_NO_CXX11_HDR_TUPLE)
+
+BOOST_PRAGMA_MESSAGE("C++03 support is deprecated in Boost.ContainerHash 1.82 and will be removed in Boost.ContainerHash 1.84.")
+
+#endif
+
+#endif // #ifndef BOOST_HASH_DETAIL_REQUIRES_CXX11_HPP_INCLUDED

include/boost/container_hash/hash.hpp

@@ -11,10 +11,12 @@
 #define BOOST_FUNCTIONAL_HASH_HASH_HPP
 
 #include <boost/container_hash/hash_fwd.hpp>
+#include <boost/container_hash/detail/requires_cxx11.hpp>
 #include <boost/container_hash/is_range.hpp>
 #include <boost/container_hash/is_contiguous_range.hpp>
 #include <boost/container_hash/is_unordered_range.hpp>
-#include <boost/container_hash/detail/hash_tuple.hpp>
+#include <boost/container_hash/is_described_class.hpp>
+#include <boost/container_hash/detail/hash_tuple_like.hpp>
 #include <boost/container_hash/detail/hash_mix.hpp>
 #include <boost/container_hash/detail/hash_range.hpp>
 #include <boost/type_traits/is_enum.hpp>
@@ -25,7 +27,16 @@
 #include <boost/type_traits/make_unsigned.hpp>
 #include <boost/type_traits/enable_if.hpp>
 #include <boost/type_traits/conjunction.hpp>
+#include <boost/type_traits/is_union.hpp>
+#include <boost/type_traits/is_same.hpp>
+#include <boost/describe/bases.hpp>
+#include <boost/describe/members.hpp>
 #include <boost/cstdint.hpp>
+
+#if defined(BOOST_DESCRIBE_CXX14)
+# include <boost/mp11/algorithm.hpp>
+#endif
+
 #include <string>
 #include <iterator>
 #include <complex>
@@ -54,6 +65,10 @@
 #include <variant>
 #endif
 
+#if !defined(BOOST_NO_CXX17_HDR_STRING_VIEW)
+# include <string_view>
+#endif
+
 namespace boost
 {
 
@@ -104,7 +119,7 @@ namespace boost
                 std::size_t seed = 0;
 
                 seed = static_cast<std::size_t>( v >> 32 ) + hash_detail::hash_mix( seed );
-                seed = static_cast<std::size_t>( v ) + hash_detail::hash_mix( seed );
+                seed = static_cast<std::size_t>( v  & 0xFFFFFFFF ) + hash_detail::hash_mix( seed );
 
                 return seed;
             }
@@ -176,12 +191,11 @@ namespace boost
     {
         template<class T,
             std::size_t Bits = sizeof(T) * CHAR_BIT,
-            int Digits = std::numeric_limits<T>::digits,
-            std::size_t size_t_bits = sizeof(std::size_t) * CHAR_BIT>
+            int Digits = std::numeric_limits<T>::digits>
         struct hash_float_impl;
 
         // float
-        template<class T, int Digits, std::size_t size_t_bits> struct hash_float_impl<T, 32, Digits, size_t_bits>
+        template<class T, int Digits> struct hash_float_impl<T, 32, Digits>
         {
             static std::size_t fn( T v )
             {
@@ -193,35 +207,19 @@ namespace boost
         };
 
         // double
-        template<class T, int Digits> struct hash_float_impl<T, 64, Digits, 64>
+        template<class T, int Digits> struct hash_float_impl<T, 64, Digits>
         {
             static std::size_t fn( T v )
             {
                 boost::uint64_t w;
                 std::memcpy( &w, &v, sizeof( v ) );
 
-                return w;
-            }
-        };
-
-        template<class T, int Digits> struct hash_float_impl<T, 64, Digits, 32>
-        {
-            static std::size_t fn( T v )
-            {
-                boost::uint32_t w[ 2 ];
-                std::memcpy( &w, &v, sizeof( v ) );
-
-                std::size_t seed = 0;
-
-                seed = static_cast<std::size_t>( w[0] ) + hash_detail::hash_mix( seed );
-                seed = static_cast<std::size_t>( w[1] ) + hash_detail::hash_mix( seed );
-
-                return seed;
+                return hash_value( w );
             }
         };
 
         // 80 bit long double in 12 bytes
-        template<class T> struct hash_float_impl<T, 96, 64, 64>
+        template<class T> struct hash_float_impl<T, 96, 64>
         {
             static std::size_t fn( T v )
             {
@@ -230,32 +228,15 @@ namespace boost
 
                 std::size_t seed = 0;
 
-                seed = static_cast<std::size_t>( w[0] ) + hash_detail::hash_mix( seed );
-                seed = static_cast<std::size_t>( w[1] ) + hash_detail::hash_mix( seed );
-
-                return seed;
-            }
-        };
-
-        template<class T> struct hash_float_impl<T, 96, 64, 32>
-        {
-            static std::size_t fn( T v )
-            {
-                boost::uint32_t w[ 3 ] = {};
-                std::memcpy( &w, &v, 80 / CHAR_BIT );
-
-                std::size_t seed = 0;
-
-                seed = static_cast<std::size_t>( w[0] ) + hash_detail::hash_mix( seed );
-                seed = static_cast<std::size_t>( w[1] ) + hash_detail::hash_mix( seed );
-                seed = static_cast<std::size_t>( w[2] ) + hash_detail::hash_mix( seed );
+                seed = hash_value( w[0] ) + hash_detail::hash_mix( seed );
+                seed = hash_value( w[1] ) + hash_detail::hash_mix( seed );
 
                 return seed;
             }
         };
 
         // 80 bit long double in 16 bytes
-        template<class T> struct hash_float_impl<T, 128, 64, 64>
+        template<class T> struct hash_float_impl<T, 128, 64>
         {
             static std::size_t fn( T v )
             {
@@ -264,32 +245,15 @@ namespace boost
 
                 std::size_t seed = 0;
 
-                seed = static_cast<std::size_t>( w[0] ) + hash_detail::hash_mix( seed );
-                seed = static_cast<std::size_t>( w[1] ) + hash_detail::hash_mix( seed );
-
-                return seed;
-            }
-        };
-
-        template<class T> struct hash_float_impl<T, 128, 64, 32>
-        {
-            static std::size_t fn( T v )
-            {
-                boost::uint32_t w[ 3 ] = {};
-                std::memcpy( &w, &v, 80 / CHAR_BIT );
-
-                std::size_t seed = 0;
-
-                seed = static_cast<std::size_t>( w[0] ) + hash_detail::hash_mix( seed );
-                seed = static_cast<std::size_t>( w[1] ) + hash_detail::hash_mix( seed );
-                seed = static_cast<std::size_t>( w[2] ) + hash_detail::hash_mix( seed );
+                seed = hash_value( w[0] ) + hash_detail::hash_mix( seed );
+                seed = hash_value( w[1] ) + hash_detail::hash_mix( seed );
 
                 return seed;
             }
         };
 
         // 128 bit long double
-        template<class T, int Digits, std::size_t size_t_bits> struct hash_float_impl<T, 128, Digits, size_t_bits>
+        template<class T, int Digits> struct hash_float_impl<T, 128, Digits>
         {
             static std::size_t fn( T v )
             {
@@ -434,6 +398,49 @@ namespace boost
         return boost::hash_unordered_range( v.begin(), v.end() );
     }
 
+#endif
+
+    // described classes
+
+#if defined(BOOST_DESCRIBE_CXX14)
+
+#if defined(_MSC_VER) && _MSC_VER == 1900
+# pragma warning(push)
+# pragma warning(disable: 4100) // unreferenced formal parameter
+#endif
+
+    template <typename T>
+    typename boost::enable_if_<container_hash::is_described_class<T>::value, std::size_t>::type
+        hash_value( T const& v )
+    {
+        static_assert( !boost::is_union<T>::value, "described unions are not supported" );
+
+        std::size_t r = 0;
+
+        using Bd = describe::describe_bases<T, describe::mod_any_access>;
+
+        mp11::mp_for_each<Bd>([&](auto D){
+
+            using B = typename decltype(D)::type;
+            boost::hash_combine( r, (B const&)v );
+
+        });
+
+        using Md = describe::describe_members<T, describe::mod_any_access>;
+
+        mp11::mp_for_each<Md>([&](auto D){
+
+            boost::hash_combine( r, v.*D.pointer );
+
+        });
+
+        return r;
+    }
+
+#if defined(_MSC_VER) && _MSC_VER == 1900
+# pragma warning(pop)
+#endif
+
 #endif
 
     // std::unique_ptr, std::shared_ptr
@@ -489,6 +496,19 @@ namespace boost
         return seed;
     }
 
+#endif
+
+    // std::nullptr_t
+
+#if !defined(BOOST_NO_CXX11_NULLPTR)
+
+    template <typename T>
+    typename boost::enable_if_<boost::is_same<T, std::nullptr_t>::value, std::size_t>::type
+        hash_value( T const& /*v*/ )
+    {
+        return boost::hash_value( static_cast<void*>( nullptr ) );
+    }
+
 #endif
 
     // std::optional
@@ -628,8 +648,30 @@ namespace boost
     };
 
 #endif
-}
 
-#undef BOOST_FUNCTIONAL_HASH_ROTL32
+    // boost::unordered::hash_is_avalanching
+
+    namespace unordered
+    {
+        template<class T> struct hash_is_avalanching;
+        template<class Ch> struct hash_is_avalanching< boost::hash< std::basic_string<Ch> > >: boost::is_integral<Ch> {};
+
+        // boost::is_integral<char8_t> is false, but should be true (https://github.com/boostorg/type_traits/issues/175)
+#if defined(__cpp_char8_t) && __cpp_char8_t >= 201811L
+        template<> struct hash_is_avalanching< boost::hash< std::basic_string<char8_t> > >: boost::true_type {};
+#endif
+
+#if !defined(BOOST_NO_CXX17_HDR_STRING_VIEW)
+
+        template<class Ch> struct hash_is_avalanching< boost::hash< std::basic_string_view<Ch> > >: boost::is_integral<Ch> {};
+
+#if defined(__cpp_char8_t) && __cpp_char8_t >= 201811L
+        template<> struct hash_is_avalanching< boost::hash< std::basic_string_view<char8_t> > >: boost::true_type {};
+#endif
+
+#endif
+    } // namespace unordered
+
+} // namespace boost
 
 #endif // #ifndef BOOST_FUNCTIONAL_HASH_HASH_HPP

include/boost/container_hash/hash_fwd.hpp

@@ -1,5 +1,5 @@
 // Copyright 2005-2009 Daniel James.
-// Copyright 2021 Peter Dimov.
+// Copyright 2021, 2022 Peter Dimov.
 // Distributed under the Boost Software License, Version 1.0.
 // https://www.boost.org/LICENSE_1_0.txt
 
@@ -17,6 +17,8 @@ namespace container_hash
 template<class T> struct is_range;
 template<class T> struct is_contiguous_range;
 template<class T> struct is_unordered_range;
+template<class T> struct is_described_class;
+template<class T> struct is_tuple_like;
 
 } // namespace container_hash
 

include/boost/container_hash/is_contiguous_range.hpp

@@ -5,12 +5,13 @@
 #ifndef BOOST_HASH_IS_CONTIGUOUS_RANGE_HPP_INCLUDED
 #define BOOST_HASH_IS_CONTIGUOUS_RANGE_HPP_INCLUDED
 
+#include <boost/container_hash/detail/requires_cxx11.hpp>
 #include <boost/container_hash/is_range.hpp>
 #include <boost/type_traits/integral_constant.hpp>
 #include <boost/config.hpp>
 #include <boost/config/workaround.hpp>
 
-#if !defined(BOOST_NO_CXX11_DECLTYPE) && !defined(BOOST_NO_SFINAE_EXPR) && !BOOST_WORKAROUND(BOOST_GCC, < 40700)
+#if !defined(BOOST_NO_CXX11_DECLTYPE) && !defined(BOOST_NO_SFINAE_EXPR) && !BOOST_WORKAROUND(BOOST_GCC, < 40700) && !BOOST_WORKAROUND(BOOST_MSVC, < 1910)
 
 #include <boost/type_traits/is_integral.hpp>
 #include <boost/type_traits/declval.hpp>

include/boost/container_hash/is_described_class.hpp

@@ -0,0 +1,38 @@
+// Copyright 2022 Peter Dimov.
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#ifndef BOOST_HASH_IS_DESCRIBED_CLASS_HPP_INCLUDED
+#define BOOST_HASH_IS_DESCRIBED_CLASS_HPP_INCLUDED
+
+#include <boost/type_traits/integral_constant.hpp>
+#include <boost/type_traits/is_union.hpp>
+#include <boost/describe/bases.hpp>
+#include <boost/describe/members.hpp>
+
+namespace boost
+{
+namespace container_hash
+{
+
+#if defined(BOOST_DESCRIBE_CXX11)
+
+template<class T> struct is_described_class: boost::integral_constant<bool,
+    describe::has_describe_bases<T>::value &&
+    describe::has_describe_members<T>::value &&
+    !boost::is_union<T>::value>
+{
+};
+
+#else
+
+template<class T> struct is_described_class: boost::false_type
+{
+};
+
+#endif
+
+} // namespace container_hash
+} // namespace boost
+
+#endif // #ifndef BOOST_HASH_IS_DESCRIBED_CLASS_HPP_INCLUDED

include/boost/container_hash/is_range.hpp

@@ -5,6 +5,7 @@
 #ifndef BOOST_HASH_IS_RANGE_HPP_INCLUDED
 #define BOOST_HASH_IS_RANGE_HPP_INCLUDED
 
+#include <boost/container_hash/detail/requires_cxx11.hpp>
 #include <boost/type_traits/integral_constant.hpp>
 #include <boost/type_traits/is_integral.hpp>
 #include <boost/type_traits/declval.hpp>

include/boost/container_hash/is_tuple_like.hpp

@@ -0,0 +1,42 @@
+#ifndef BOOST_HASH_IS_TUPLE_LIKE_HPP_INCLUDED
+#define BOOST_HASH_IS_TUPLE_LIKE_HPP_INCLUDED
+
+// Copyright 2017, 2022 Peter Dimov.
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/type_traits/integral_constant.hpp>
+#include <boost/config.hpp>
+#include <boost/config/workaround.hpp>
+#include <utility>
+
+namespace boost
+{
+namespace hash_detail
+{
+
+template<class T, class E = true_type> struct is_tuple_like_: false_type
+{
+};
+
+#if !defined(BOOST_NO_CXX11_HDR_TUPLE) && !BOOST_WORKAROUND(BOOST_MSVC, <= 1800)
+
+template<class T> struct is_tuple_like_<T, integral_constant<bool, std::tuple_size<T>::value == std::tuple_size<T>::value> >: true_type
+{
+};
+
+#endif
+
+} // namespace hash_detail
+
+namespace container_hash
+{
+
+template<class T> struct is_tuple_like: hash_detail::is_tuple_like_<T>
+{
+};
+
+} // namespace container_hash
+} // namespace boost
+
+#endif // #ifndef BOOST_HASH_IS_TUPLE_LIKE_HPP_INCLUDED

test/CMakeLists.txt

@@ -1,4 +1,4 @@
-# Copyright 2018, 2019, 2021 Peter Dimov
+# Copyright 2018, 2019, 2021, 2022 Peter Dimov
 # Distributed under the Boost Software License, Version 1.0.
 # See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt
 
@@ -6,6 +6,7 @@ include(BoostTestJamfile OPTIONAL RESULT_VARIABLE HAVE_BOOST_TEST)
 
 if(HAVE_BOOST_TEST)
 
-boost_test_jamfile(FILE Jamfile.v2 LINK_LIBRARIES Boost::container_hash Boost::core Boost::utility)
+boost_test_jamfile(FILE Jamfile.v2
+  LINK_LIBRARIES Boost::container_hash Boost::core Boost::utility Boost::unordered)
 
 endif()

test/Jamfile.v2

@@ -77,7 +77,7 @@ run hash_string_test2.cpp ;
 # for gcc-4.8
 local fs-path-req = "-<toolset>gcc:<cxxflags>-Wshadow" "-<toolset>gcc:<cxxflags>-Wconversion" ;
 
-run hash_fs_path_test.cpp /boost//filesystem/<warnings>off : : : $(fs-path-req) <toolset>msvc-14.0,<cxxstd>latest:<build>no <toolset>msvc-8.0:<build>no ;
+run hash_fs_path_test.cpp /boost//filesystem/<warnings>off : : : $(fs-path-req) <toolset>msvc-14.0,<cxxstd>latest:<build>no <toolset>msvc-8.0:<build>no <undefined-sanitizer>norecover:<link>static ;
 run is_range_test2.cpp : : : $(fs-path-req) <toolset>msvc-8.0:<build>no ;
 
 run hash_container_test.cpp ;
@@ -101,3 +101,27 @@ run hash_unordered_map_test.cpp ;
 run is_range_test3.cpp ;
 run is_contiguous_range_test2.cpp ;
 run is_unordered_range_test2.cpp ;
+run is_contiguous_range_test3.cpp ;
+
+run is_described_class_test.cpp
+  : : : <warnings>extra ;
+run is_described_class_test2.cpp
+  : : : <warnings>extra ;
+run is_described_class_test3.cpp
+  : : : <warnings>extra ;
+
+run described_class_test.cpp
+  : : : <warnings>extra ;
+
+run hash_is_avalanching_test.cpp ;
+run hash_is_avalanching_test2.cpp ;
+
+run hash_integral_test2.cpp ;
+
+run hash_nullptr_test.cpp ;
+
+run is_tuple_like_test.cpp ;
+
+run hash_tuple_like_test.cpp ;
+run hash_tuple_like_test2.cpp
+  : : : <warnings>extra ;

test/cmake_subdir_test/CMakeLists.txt

@@ -11,6 +11,8 @@ add_subdirectory(../.. boostorg/container_hash)
 add_subdirectory(../../../config boostorg/config)
 add_subdirectory(../../../type_traits boostorg/type_traits)
 add_subdirectory(../../../static_assert boostorg/static_assert)
+add_subdirectory(../../../describe boostorg/describe)
+add_subdirectory(../../../mp11 boostorg/mp11)
 
 add_executable(quick ../quick.cpp)
 target_link_libraries(quick Boost::container_hash)

test/described_class_test.cpp

@@ -0,0 +1,159 @@
+// Copyright 2022 Peter Dimov.
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#if defined(__clang__)
+# pragma clang diagnostic ignored "-Wunused-private-field"
+#endif
+
+#include <boost/container_hash/hash.hpp>
+#include <boost/describe/class.hpp>
+#include <boost/describe/operators.hpp>
+#include <boost/core/lightweight_test_trait.hpp>
+
+#if !defined(BOOST_DESCRIBE_CXX14)
+
+#include <boost/config/pragma_message.hpp>
+
+BOOST_PRAGMA_MESSAGE( "Skipping test because BOOST_DESCRIBE_CXX14 is not defined" )
+
+int main() {}
+
+#else
+
+struct X1
+{
+    int m;
+    explicit X1( int m_ ): m( m_ ) {}
+};
+
+BOOST_DESCRIBE_STRUCT( X1, (), (m) )
+
+struct X2
+{
+    int m;
+    explicit X2( int m_ ): m( m_ ) {}
+};
+
+BOOST_DESCRIBE_STRUCT( X2, (), (m) )
+
+struct X3
+{
+    int m;
+    explicit X3( int m_ ): m( m_ ) {}
+};
+
+BOOST_DESCRIBE_STRUCT( X3, (), (m) )
+
+class Y: public X1, protected X2, private X3
+{
+public:
+
+    int m1;
+
+protected:
+
+    int m2;
+
+private:
+
+    int m3;
+
+public:
+
+    Y( int x1, int x2, int x3, int m1_, int m2_, int m3_ ):
+      X1( x1 ), X2( x2 ), X3( x3 ), m1( m1_ ), m2( m2_ ), m3( m3_ ) {}
+
+    BOOST_DESCRIBE_CLASS( Y, (X1, X2, X3), (m1), (m2), (m3) )
+};
+
+using boost::describe::operators::operator==;
+using boost::describe::operators::operator!=;
+using boost::describe::operators::operator<<;
+
+int main()
+{
+    Y y1( 0, 0, 0, 0, 0, 0 );
+
+    BOOST_TEST_EQ( y1, y1 );
+    BOOST_TEST_EQ( boost::hash<Y>()(y1), boost::hash<Y>()(y1) );
+
+    Y y2( 1, 0, 0, 0, 0, 0 );
+
+    BOOST_TEST_NE( y1, y2 );
+    BOOST_TEST_NE( boost::hash<Y>()(y1), boost::hash<Y>()(y2) );
+
+    Y y3( 0, 1, 0, 0, 0, 0 );
+
+    BOOST_TEST_NE( y1, y3 );
+    BOOST_TEST_NE( boost::hash<Y>()(y1), boost::hash<Y>()(y3) );
+
+    BOOST_TEST_NE( y2, y3 );
+    BOOST_TEST_NE( boost::hash<Y>()(y2), boost::hash<Y>()(y3) );
+
+    Y y4( 0, 0, 1, 0, 0, 0 );
+
+    BOOST_TEST_NE( y1, y4 );
+    BOOST_TEST_NE( boost::hash<Y>()(y1), boost::hash<Y>()(y4) );
+
+    BOOST_TEST_NE( y2, y4 );
+    BOOST_TEST_NE( boost::hash<Y>()(y2), boost::hash<Y>()(y4) );
+
+    BOOST_TEST_NE( y3, y4 );
+    BOOST_TEST_NE( boost::hash<Y>()(y3), boost::hash<Y>()(y4) );
+
+    Y y5( 0, 0, 0, 1, 0, 0 );
+
+    BOOST_TEST_NE( y1, y5 );
+    BOOST_TEST_NE( boost::hash<Y>()(y1), boost::hash<Y>()(y5) );
+
+    BOOST_TEST_NE( y2, y5 );
+    BOOST_TEST_NE( boost::hash<Y>()(y2), boost::hash<Y>()(y5) );
+
+    BOOST_TEST_NE( y3, y5 );
+    BOOST_TEST_NE( boost::hash<Y>()(y3), boost::hash<Y>()(y5) );
+
+    BOOST_TEST_NE( y4, y5 );
+    BOOST_TEST_NE( boost::hash<Y>()(y4), boost::hash<Y>()(y5) );
+
+    Y y6( 0, 0, 0, 0, 1, 0 );
+
+    BOOST_TEST_NE( y1, y6 );
+    BOOST_TEST_NE( boost::hash<Y>()(y1), boost::hash<Y>()(y6) );
+
+    BOOST_TEST_NE( y2, y6 );
+    BOOST_TEST_NE( boost::hash<Y>()(y2), boost::hash<Y>()(y6) );
+
+    BOOST_TEST_NE( y3, y6 );
+    BOOST_TEST_NE( boost::hash<Y>()(y3), boost::hash<Y>()(y6) );
+
+    BOOST_TEST_NE( y4, y6 );
+    BOOST_TEST_NE( boost::hash<Y>()(y4), boost::hash<Y>()(y6) );
+
+    BOOST_TEST_NE( y5, y6 );
+    BOOST_TEST_NE( boost::hash<Y>()(y5), boost::hash<Y>()(y6) );
+
+    Y y7( 0, 0, 0, 0, 0, 1 );
+
+    BOOST_TEST_NE( y1, y7 );
+    BOOST_TEST_NE( boost::hash<Y>()(y1), boost::hash<Y>()(y7) );
+
+    BOOST_TEST_NE( y2, y7 );
+    BOOST_TEST_NE( boost::hash<Y>()(y2), boost::hash<Y>()(y7) );
+
+    BOOST_TEST_NE( y3, y7 );
+    BOOST_TEST_NE( boost::hash<Y>()(y3), boost::hash<Y>()(y7) );
+
+    BOOST_TEST_NE( y4, y7 );
+    BOOST_TEST_NE( boost::hash<Y>()(y4), boost::hash<Y>()(y7) );
+
+    BOOST_TEST_NE( y5, y7 );
+    BOOST_TEST_NE( boost::hash<Y>()(y5), boost::hash<Y>()(y7) );
+
+    BOOST_TEST_NE( y6, y7 );
+    BOOST_TEST_NE( boost::hash<Y>()(y6), boost::hash<Y>()(y7) );
+
+    return boost::report_errors();
+}
+
+#endif

test/hash_complex_test.cpp

@@ -3,6 +3,8 @@
 // Distributed under the Boost Software License, Version 1.0. (See accompanying
 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
 
+#define _SILENCE_NONFLOATING_COMPLEX_DEPRECATION_WARNING
+
 #include "./config.hpp"
 
 #if !defined(BOOST_HASH_TEST_EXTENSIONS)

test/hash_container_test.cpp

@@ -48,5 +48,13 @@ int main()
     test<float>();
     test<double>();
 
+#if defined(__cpp_char8_t) && __cpp_char8_t >= 201811L
+    test<char8_t>();
+#endif
+
+#if defined(__cpp_lib_byte) && __cpp_lib_byte >= 201603L
+    test<std::byte>();
+#endif
+
     return boost::report_errors();
 }

test/hash_function_pointer_test.cpp

@@ -14,8 +14,8 @@
 #include <boost/core/lightweight_test.hpp>
 #include "./compile_time.hpp"
 
-void void_func1() { static int x = 1; ++x; }
-void void_func2() { static int x = 2; --x; }
+void void_func1() { static int x = 1; ++x; (void)x; }
+void void_func2() { static int x = 2; --x; (void)x; }
 int int_func1(int) { return 0; }
 int int_func2(int) { return 1; }
 

test/hash_integral_test.cpp

@@ -7,7 +7,7 @@
 #include <boost/core/lightweight_test.hpp>
 #include <boost/core/type_name.hpp>
 #include <boost/type_traits/is_signed.hpp>
-#include <set>
+#include <boost/config.hpp>
 
 #if defined(BOOST_MSVC)
 #pragma warning(disable: 4127) // conditional expression is constant

test/hash_integral_test2.cpp

@@ -0,0 +1,52 @@
+// Copyright 2005-2009 Daniel James.
+// Copyright 2021 Peter Dimov.
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/container_hash/hash.hpp>
+#include <boost/core/lightweight_test.hpp>
+#include <boost/core/type_name.hpp>
+#include <boost/type_traits/is_signed.hpp>
+#include <boost/type_traits/make_unsigned.hpp>
+#include <boost/static_assert.hpp>
+#include <boost/config.hpp>
+
+// This test checks that values representable in a signed
+// and the corresponding unsigned type hash to the same value
+
+template<class T>
+void signed_unsigned_test()
+{
+    BOOST_STATIC_ASSERT( boost::is_signed<T>::value );
+
+    typedef typename boost::make_unsigned<T>::type U;
+
+    T x = std::numeric_limits<T>::max();
+
+    do
+    {
+        BOOST_TEST_EQ( boost::hash<T>()( x ), boost::hash<U>()( static_cast<U>( x ) ) );
+        x /= 3;
+    }
+    while( x > 0 );
+}
+
+#define TEST(type) std::cerr << "Testing: " #type " (" << boost::core::type_name<type>() << ")\n"; signed_unsigned_test<type>();
+
+int main()
+{
+    TEST(signed char)
+    TEST(short)
+    TEST(int)
+    TEST(long)
+
+#if !defined(BOOST_NO_LONG_LONG)
+    TEST(boost::long_long_type)
+#endif
+
+#if defined(BOOST_HAS_INT128)
+    TEST(boost::int128_type)
+#endif
+
+    return boost::report_errors();
+}

test/hash_is_avalanching_test.cpp

@@ -0,0 +1,41 @@
+// Copyright 2022 Peter Dimov.
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/container_hash/hash.hpp>
+#include <boost/core/lightweight_test_trait.hpp>
+#include <boost/unordered/hash_traits.hpp>
+#include <boost/config.hpp>
+#include <string>
+
+enum my_char { min = 0, max = 255 };
+
+int main()
+{
+    using boost::unordered::hash_is_avalanching;
+
+    BOOST_TEST_TRAIT_TRUE(( hash_is_avalanching< boost::hash<std::string> > ));
+    BOOST_TEST_TRAIT_TRUE(( hash_is_avalanching< boost::hash<std::wstring> > ));
+
+#if !defined(BOOST_NO_CXX11_CHAR16_T)
+
+    BOOST_TEST_TRAIT_TRUE(( hash_is_avalanching< boost::hash<std::u16string> > ));
+
+#endif
+
+#if !defined(BOOST_NO_CXX11_CHAR32_T)
+
+    BOOST_TEST_TRAIT_TRUE(( hash_is_avalanching< boost::hash<std::u32string> > ));
+
+#endif
+
+#if defined(__cpp_char8_t) && __cpp_char8_t >= 201811L
+
+    BOOST_TEST_TRAIT_TRUE(( hash_is_avalanching< boost::hash< std::basic_string<char8_t> > > ));
+
+#endif
+
+    BOOST_TEST_TRAIT_FALSE(( hash_is_avalanching< boost::hash<std::basic_string<my_char> > > ));
+
+    return boost::report_errors();
+}

test/hash_is_avalanching_test2.cpp

@@ -0,0 +1,52 @@
+// Copyright 2022 Peter Dimov.
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/container_hash/hash.hpp>
+#include <boost/core/lightweight_test_trait.hpp>
+#include <boost/config.hpp>
+#include <boost/config/pragma_message.hpp>
+
+#if defined(BOOST_NO_CXX17_HDR_STRING_VIEW)
+
+BOOST_PRAGMA_MESSAGE( "Test skipped, BOOST_NO_CXX17_HDR_STRING_VIEW is defined" )
+int main() {}
+
+#else
+
+#include <boost/unordered/hash_traits.hpp>
+#include <string_view>
+
+enum my_char { min = 0, max = 255 };
+
+int main()
+{
+    using boost::unordered::hash_is_avalanching;
+
+    BOOST_TEST_TRAIT_TRUE(( hash_is_avalanching< boost::hash<std::string_view> > ));
+    BOOST_TEST_TRAIT_TRUE(( hash_is_avalanching< boost::hash<std::wstring_view> > ));
+
+#if !defined(BOOST_NO_CXX11_CHAR16_T)
+
+    BOOST_TEST_TRAIT_TRUE(( hash_is_avalanching< boost::hash<std::u16string_view> > ));
+
+#endif
+
+#if !defined(BOOST_NO_CXX11_CHAR32_T)
+
+    BOOST_TEST_TRAIT_TRUE(( hash_is_avalanching< boost::hash<std::u32string_view> > ));
+
+#endif
+
+#if defined(__cpp_char8_t) && __cpp_char8_t >= 201811L
+
+    BOOST_TEST_TRAIT_TRUE(( hash_is_avalanching< boost::hash< std::basic_string_view<char8_t> > > ));
+
+#endif
+
+    BOOST_TEST_TRAIT_FALSE(( hash_is_avalanching< boost::hash<std::basic_string_view<my_char> > > ));
+
+    return boost::report_errors();
+}
+
+#endif

test/hash_nullptr_test.cpp

@@ -0,0 +1,41 @@
+// Copyright 2022 Peter Dimov.
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/container_hash/hash.hpp>
+#include <boost/core/lightweight_test.hpp>
+#include <boost/config.hpp>
+#include <boost/config/pragma_message.hpp>
+#include <cstddef>
+
+#if defined(BOOST_NO_CXX11_NULLPTR)
+
+BOOST_PRAGMA_MESSAGE( "Test skipped, BOOST_NO_CXX11_NULLPTR is defined" )
+int main() {}
+
+#else
+
+template<class T> std::size_t hv( T const& x )
+{
+    return boost::hash<T>()( x );
+}
+
+int main()
+{
+    {
+        BOOST_TEST_EQ( hv((void*)0), hv(nullptr) );
+    }
+
+    {
+        int x = 0;
+
+        BOOST_TEST_EQ( hv((int*)0), hv(nullptr) );
+        BOOST_TEST_NE( hv(&x), hv(nullptr) );
+
+        (void)x;
+    }
+
+    return boost::report_errors();
+}
+
+#endif

test/hash_reference_values.cpp

@@ -171,16 +171,16 @@ int main()
 
 #if SIZE_MAX == 4294967295U
 
-    BOOST_TEST_EQ( hv(1.0), 1072693248U );
-    BOOST_TEST_EQ( hv(-1.0), 3220176896U );
-    BOOST_TEST_EQ( hv(3.14), 3972386992U );
-    BOOST_TEST_EQ( hv(-3.14), 1824903344U );
-    BOOST_TEST_EQ( hv(1e-308), 2213556530U );
-    BOOST_TEST_EQ( hv(-1e-308), 66072882U );
-    BOOST_TEST_EQ( hv(1e+308), 2623678890U );
-    BOOST_TEST_EQ( hv(-1e+308), 476195242U );
-    BOOST_TEST_EQ( hv(std::numeric_limits<double>::infinity()), 2146435072U );
-    BOOST_TEST_EQ( hv(-std::numeric_limits<double>::infinity()), 4293918720U );
+    BOOST_TEST_EQ( hv(1.0), 2619008688U );
+    BOOST_TEST_EQ( hv(-1.0), 146497060U );
+    BOOST_TEST_EQ( hv(3.14), 101651732U );
+    BOOST_TEST_EQ( hv(-3.14), 210858151U );
+    BOOST_TEST_EQ( hv(1e-308), 3911789313U );
+    BOOST_TEST_EQ( hv(-1e-308), 1812507313U );
+    BOOST_TEST_EQ( hv(1e+308), 987802568U );
+    BOOST_TEST_EQ( hv(-1e+308), 1639042439U );
+    BOOST_TEST_EQ( hv(std::numeric_limits<double>::infinity()), 3227645345U );
+    BOOST_TEST_EQ( hv(-std::numeric_limits<double>::infinity()), 2247339177U );
 
 #else
 
@@ -207,21 +207,23 @@ int main()
 
     if( ldbits == 64 )
     {
-        BOOST_TEST_EQ( hv(1.0L), 1072693248U );
-        BOOST_TEST_EQ( hv(-1.0L), 3220176896U );
-        BOOST_TEST_EQ( hv(3.14L), 3972386992U );
-        BOOST_TEST_EQ( hv(-3.14L), 1824903344U );
-        BOOST_TEST_EQ( hv(std::numeric_limits<long double>::infinity()), 2146435072U );
-        BOOST_TEST_EQ( hv(-std::numeric_limits<long double>::infinity()), 4293918720U );
+        BOOST_TEST_EQ( hv(1.0L), hv(1.0) );
+        BOOST_TEST_EQ( hv(-1.0L), hv(-1.0) );
+        BOOST_TEST_EQ( hv(3.14L), hv(3.14) );
+        BOOST_TEST_EQ( hv(-3.14L), hv(-3.14) );
+        BOOST_TEST_EQ( hv(std::numeric_limits<long double>::infinity()), hv(std::numeric_limits<double>::infinity()) );
+        BOOST_TEST_EQ( hv(-std::numeric_limits<long double>::infinity()), hv(-std::numeric_limits<double>::infinity()) );
     }
     else
     {
-        BOOST_TEST_EQ( hv(1.0L), 3770520689U );
-        BOOST_TEST_EQ( hv(-1.0L), 3770553457U );
-        BOOST_TEST_EQ( hv(3.14L), 1150018772U );
-        BOOST_TEST_EQ( hv(-3.14L), 1150051540U );
-        BOOST_TEST_EQ( hv(std::numeric_limits<long double>::infinity()), 3770537073U );
-        BOOST_TEST_EQ( hv(-std::numeric_limits<long double>::infinity()), 3770569841U );
+        // ldbits == 96
+
+        BOOST_TEST_EQ( hv(1.0L), 3632050780U );
+        BOOST_TEST_EQ( hv(-1.0L), 3632083548U );
+        BOOST_TEST_EQ( hv(3.14L), 1742026549U );
+        BOOST_TEST_EQ( hv(-3.14L), 1742059317U );
+        BOOST_TEST_EQ( hv(std::numeric_limits<long double>::infinity()), 3632067164U );
+        BOOST_TEST_EQ( hv(-std::numeric_limits<long double>::infinity()), 3632099932U );
     }
 
 #else
@@ -246,9 +248,7 @@ int main()
     }
     else
     {
-        // ldbits == 128  && std::numeric_limits<long double>::digits == 113
-        // under ARM64 and S390x, but the values differ presumably because of
-        // __FLOAT_WORD_ORDER__
+        // ldbits == 128 && std::numeric_limits<long double>::digits == 113
 
         BOOST_TEST_EQ( hv(1.0L), 4611404543450677248ULL );
         BOOST_TEST_EQ( hv(-1.0L), 13834776580305453056ULL );
@@ -284,19 +284,19 @@ int main()
     // string
 #if SIZE_MAX == 4294967295U
 
-    BOOST_TEST_EQ( hv(std::string()), 1580013426U );
-    BOOST_TEST_EQ( hv(std::string("abc")), 469308065U );
-    BOOST_TEST_EQ( hv(std::string("\0", 1)), 165258820U );
-    BOOST_TEST_EQ( hv(std::string("\0\0", 2)), 4017288109U );
-    BOOST_TEST_EQ( hv(std::string("\0\0\0", 3)), 1352445396U );
+    BOOST_TEST_EQ( hv(std::string()), 1868390524U );
+    BOOST_TEST_EQ( hv(std::string("abc")), 3674866719U );
+    BOOST_TEST_EQ( hv(std::string("\0", 1)), 1965885047U );
+    BOOST_TEST_EQ( hv(std::string("\0\0", 2)), 54340706U );
+    BOOST_TEST_EQ( hv(std::string("\0\0\0", 3)), 688730713U );
 
 #else
 
-    BOOST_TEST_EQ( hv(std::string()), 2220755840493918647ULL );
-    BOOST_TEST_EQ( hv(std::string("abc")), 7565583854499162206ULL );
-    BOOST_TEST_EQ( hv(std::string("\0", 1)), 1241131678047372712ULL );
-    BOOST_TEST_EQ( hv(std::string("\0\0", 2)), 152341731040131640ULL );
-    BOOST_TEST_EQ( hv(std::string("\0\0\0", 3)), 12957252994983528908ULL );
+    BOOST_TEST_EQ( hv(std::string()), 2060355526954642342ULL );
+    BOOST_TEST_EQ( hv(std::string("abc")), 2539195663733406973ULL );
+    BOOST_TEST_EQ( hv(std::string("\0", 1)), 18432168439372857722ULL );
+    BOOST_TEST_EQ( hv(std::string("\0\0", 2)), 6494115972580589074ULL );
+    BOOST_TEST_EQ( hv(std::string("\0\0\0", 3)), 4419026507380069870ULL );
 
 #endif
 
@@ -344,10 +344,10 @@ int main()
 
 #if SIZE_MAX == 4294967295U
 
-    BOOST_TEST_EQ( hv(std::complex<double>(+1.0, 0.0)), 1072693248U );
-    BOOST_TEST_EQ( hv(std::complex<double>(-1.0, 0.0)), 3220176896U );
-    BOOST_TEST_EQ( hv(std::complex<double>(0.0, +1.0)), 2619008688U );
-    BOOST_TEST_EQ( hv(std::complex<double>(0.0, -1.0)), 146497060U );
+    BOOST_TEST_EQ( hv(std::complex<double>(+1.0, 0.0)), 2619008688U );
+    BOOST_TEST_EQ( hv(std::complex<double>(-1.0, 0.0)), 146497060U );
+    BOOST_TEST_EQ( hv(std::complex<double>(0.0, +1.0)), 22395692U );
+    BOOST_TEST_EQ( hv(std::complex<double>(0.0, -1.0)), 1449221192U );
 
 #else
 
@@ -376,17 +376,17 @@ int main()
     // vector<char>
 #if SIZE_MAX == 4294967295U
 
-    BOOST_TEST_EQ( hv(std::vector<char>(0)), 1580013426U );
-    BOOST_TEST_EQ( hv(std::vector<char>(1)), 165258820U );
-    BOOST_TEST_EQ( hv(std::vector<char>(2)), 4017288109U );
-    BOOST_TEST_EQ( hv(std::vector<char>(3)), 1352445396U );
+    BOOST_TEST_EQ( hv(std::vector<char>(0)), 1868390524U );
+    BOOST_TEST_EQ( hv(std::vector<char>(1)), 1965885047U );
+    BOOST_TEST_EQ( hv(std::vector<char>(2)), 54340706U );
+    BOOST_TEST_EQ( hv(std::vector<char>(3)), 688730713U );
 
 #else
 
-    BOOST_TEST_EQ( hv(std::vector<char>(0)), 2220755840493918647ULL );
-    BOOST_TEST_EQ( hv(std::vector<char>(1)), 1241131678047372712ULL );
-    BOOST_TEST_EQ( hv(std::vector<char>(2)), 152341731040131640ULL );
-    BOOST_TEST_EQ( hv(std::vector<char>(3)), 12957252994983528908ULL );
+    BOOST_TEST_EQ( hv(std::vector<char>(0)), 2060355526954642342ULL );
+    BOOST_TEST_EQ( hv(std::vector<char>(1)), 18432168439372857722ULL );
+    BOOST_TEST_EQ( hv(std::vector<char>(2)), 6494115972580589074ULL );
+    BOOST_TEST_EQ( hv(std::vector<char>(3)), 4419026507380069870ULL );
 
 #endif
 
@@ -427,17 +427,17 @@ int main()
     // list<char>
 #if SIZE_MAX == 4294967295U
 
-    BOOST_TEST_EQ( hv(std::list<char>(0)), 1580013426U );
-    BOOST_TEST_EQ( hv(std::list<char>(1)), 165258820U );
-    BOOST_TEST_EQ( hv(std::list<char>(2)), 4017288109U );
-    BOOST_TEST_EQ( hv(std::list<char>(3)), 1352445396U );
+    BOOST_TEST_EQ( hv(std::list<char>(0)), 1868390524U );
+    BOOST_TEST_EQ( hv(std::list<char>(1)), 1965885047U );
+    BOOST_TEST_EQ( hv(std::list<char>(2)), 54340706U );
+    BOOST_TEST_EQ( hv(std::list<char>(3)), 688730713U );
 
 #else
 
-    BOOST_TEST_EQ( hv(std::list<char>(0)), 2220755840493918647ULL );
-    BOOST_TEST_EQ( hv(std::list<char>(1)), 1241131678047372712ULL );
-    BOOST_TEST_EQ( hv(std::list<char>(2)), 152341731040131640ULL );
-    BOOST_TEST_EQ( hv(std::list<char>(3)), 12957252994983528908ULL );
+    BOOST_TEST_EQ( hv(std::list<char>(0)), 2060355526954642342ULL );
+    BOOST_TEST_EQ( hv(std::list<char>(1)), 18432168439372857722ULL );
+    BOOST_TEST_EQ( hv(std::list<char>(2)), 6494115972580589074ULL );
+    BOOST_TEST_EQ( hv(std::list<char>(3)), 4419026507380069870ULL );
 
 #endif
 

test/hash_tuple_like_test.cpp

@@ -0,0 +1,204 @@
+// Copyright 2022 Peter Dimov.
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#if defined(__clang__)
+# pragma clang diagnostic ignored "-Wmismatched-tags"
+#endif
+
+#include <boost/container_hash/hash.hpp>
+#include <boost/core/lightweight_test.hpp>
+#include <boost/type_traits/enable_if.hpp>
+#include <boost/type_traits/is_same.hpp>
+#include <boost/type_traits/integral_constant.hpp>
+#include <boost/config.hpp>
+#include <utility>
+
+#if !defined(BOOST_NO_CXX11_HDR_TUPLE)
+
+#include <tuple>
+
+namespace user
+{
+
+struct Y1
+{
+    int a;
+    int b;
+};
+
+template<std::size_t I> int& get( Y1& v );
+template<std::size_t I> int const& get( Y1 const& v );
+
+template<> int& get<0>( Y1& v )
+{
+    return v.a;
+}
+
+template<> int const& get<0>( Y1 const& v )
+{
+    return v.a;
+}
+
+template<> int& get<1>( Y1& v )
+{
+    return v.b;
+}
+
+template<> int const& get<1>( Y1 const& v )
+{
+    return v.b;
+}
+
+struct Y2
+{
+    int a;
+    int b;
+
+    template<class T> friend
+        typename boost::enable_if_<boost::is_same<T, Y2>::value, std::size_t>::type
+        hash_value( T const& v )
+    {
+        std::size_t seed = 0;
+
+        boost::hash_combine( seed, v.a );
+        boost::hash_combine( seed, v.b );
+
+        return seed;
+    }
+};
+
+} // namespace user
+
+namespace std
+{
+
+template<> struct tuple_size<user::Y1>: std::integral_constant<std::size_t, 2>
+{
+};
+
+template<> struct tuple_size<user::Y2>: std::integral_constant<std::size_t, 2>
+{
+};
+
+} // namespace std
+
+namespace boost
+{
+namespace container_hash
+{
+
+    template<> struct is_tuple_like<user::Y2>: boost::false_type {};
+
+} // namespace container_hash
+} // namespace boost
+
+#endif
+
+template<class T> std::size_t hv( T const& t )
+{
+    return boost::hash<T>()( t );
+}
+
+int main()
+{
+    {
+        std::pair<int, int> tp( 1, 2 );
+        int const a[] = { 1, 2 };
+
+        BOOST_TEST_EQ( hv(tp), hv(a) );
+    }
+
+#if !defined(BOOST_NO_CXX11_HDR_TUPLE)
+
+    {
+        std::tuple<> tp;
+
+        BOOST_TEST_EQ( hv(tp), 0u );
+    }
+
+    {
+        std::tuple<int> tp( 1 );
+        int const a[] = { 1 };
+
+        BOOST_TEST_EQ( hv(tp), hv(a) );
+    }
+
+    {
+        std::tuple<int, int> tp( 1, 2 );
+        int const a[] = { 1, 2 };
+
+        BOOST_TEST_EQ( hv(tp), hv(a) );
+    }
+
+    {
+        std::tuple<int, int, int> tp( 1, 2, 3 );
+        int const a[] = { 1, 2, 3 };
+
+        BOOST_TEST_EQ( hv(tp), hv(a) );
+    }
+
+    {
+        std::tuple<int, int, int, int> tp( 1, 2, 3, 4 );
+        int const a[] = { 1, 2, 3, 4 };
+
+        BOOST_TEST_EQ( hv(tp), hv(a) );
+    }
+
+    {
+        std::tuple<int, int, int, int, int> tp( 1, 2, 3, 4, 5 );
+        int const a[] = { 1, 2, 3, 4, 5 };
+
+        BOOST_TEST_EQ( hv(tp), hv(a) );
+    }
+
+    {
+        std::tuple<int, int, int, int, int, int> tp( 1, 2, 3, 4, 5, 6 );
+        int const a[] = { 1, 2, 3, 4, 5, 6 };
+
+        BOOST_TEST_EQ( hv(tp), hv(a) );
+    }
+
+    {
+        std::tuple<int, int, int, int, int, int, int> tp( 1, 2, 3, 4, 5, 6, 7 );
+        int const a[] = { 1, 2, 3, 4, 5, 6, 7 };
+
+        BOOST_TEST_EQ( hv(tp), hv(a) );
+    }
+
+    {
+        std::tuple<int, int, int, int, int, int, int, int> tp( 1, 2, 3, 4, 5, 6, 7, 8 );
+        int const a[] = { 1, 2, 3, 4, 5, 6, 7, 8 };
+
+        BOOST_TEST_EQ( hv(tp), hv(a) );
+    }
+
+    {
+        std::tuple<int, int, int, int, int, int, int, int, int> tp( 1, 2, 3, 4, 5, 6, 7, 8, 9 );
+        int const a[] = { 1, 2, 3, 4, 5, 6, 7, 8, 9 };
+
+        BOOST_TEST_EQ( hv(tp), hv(a) );
+    }
+
+#if !BOOST_WORKAROUND(BOOST_MSVC, <= 1800)
+
+    {
+        user::Y1 tp = { 1, 2 };
+        int const a[] = { 1, 2 };
+
+        BOOST_TEST_EQ( hv(tp), hv(a) );
+    }
+
+#endif
+
+    {
+        user::Y2 tp = { 1, 2 };
+        int const a[] = { 1, 2 };
+
+        BOOST_TEST_EQ( hv(tp), hv(a) );
+    }
+
+#endif
+
+    return boost::report_errors();
+}

test/hash_tuple_like_test2.cpp

@@ -0,0 +1,78 @@
+// Copyright 2022 Peter Dimov.
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#if defined(__clang__)
+# pragma clang diagnostic ignored "-Wmismatched-tags"
+#endif
+
+#include <boost/container_hash/hash.hpp>
+#include <boost/core/lightweight_test.hpp>
+#include <boost/type_traits/integral_constant.hpp>
+#include <boost/describe/class.hpp>
+#include <boost/config.hpp>
+#include <boost/config/pragma_message.hpp>
+#include <utility>
+
+#if defined(BOOST_NO_CXX11_HDR_TUPLE)
+
+BOOST_PRAGMA_MESSAGE( "Skipping test because BOOST_NO_CXX11_HDR_TUPLE is defined" )
+int main() {}
+
+#elif !defined(BOOST_DESCRIBE_CXX14)
+
+BOOST_PRAGMA_MESSAGE( "Skipping test because BOOST_DESCRIBE_CXX14 is not defined" )
+int main() {}
+
+#else
+
+namespace user
+{
+
+struct Y3
+{
+    int a;
+    int b;
+};
+
+BOOST_DESCRIBE_STRUCT(Y3, (), (a, b))
+
+} // namespace user
+
+namespace std
+{
+
+template<> struct tuple_size<user::Y3>: std::integral_constant<std::size_t, 2>
+{
+};
+
+} // namespace std
+
+namespace boost
+{
+namespace container_hash
+{
+
+    template<> struct is_tuple_like<user::Y3>: boost::false_type {};
+
+} // namespace container_hash
+} // namespace boost
+
+template<class T> std::size_t hv( T const& t )
+{
+    return boost::hash<T>()( t );
+}
+
+int main()
+{
+    {
+        user::Y3 tp = { 1, 2 };
+        int const a[] = { 1, 2 };
+
+        BOOST_TEST_EQ( hv(tp), hv(a) );
+    }
+
+    return boost::report_errors();
+}
+
+#endif

test/is_contiguous_range_test.cpp

@@ -51,7 +51,7 @@ int main()
     BOOST_TEST_TRAIT_TRUE((is_contiguous_range<std::wstring const>));
 
 // std::vector doesn't have data() in C++03
-#if !defined(BOOST_NO_CXX11_DECLTYPE) && !defined(BOOST_NO_SFINAE_EXPR) && !BOOST_WORKAROUND(BOOST_GCC, < 40700)
+#if !defined(BOOST_NO_CXX11_DECLTYPE) && !defined(BOOST_NO_SFINAE_EXPR) && !BOOST_WORKAROUND(BOOST_GCC, < 40700) && !BOOST_WORKAROUND(BOOST_MSVC, < 1910)
     BOOST_TEST_TRAIT_TRUE((is_contiguous_range< std::vector<X> >));
     BOOST_TEST_TRAIT_TRUE((is_contiguous_range< std::vector<X> const >));
 #endif

test/is_contiguous_range_test2.cpp

@@ -50,7 +50,7 @@ int main()
 {
     using boost::container_hash::is_contiguous_range;
 
-#if !defined(BOOST_NO_CXX11_DECLTYPE) && !defined(BOOST_NO_SFINAE_EXPR) && !BOOST_WORKAROUND(BOOST_GCC, < 40700)
+#if !defined(BOOST_NO_CXX11_DECLTYPE) && !defined(BOOST_NO_SFINAE_EXPR) && !BOOST_WORKAROUND(BOOST_GCC, < 40700) && !BOOST_WORKAROUND(BOOST_MSVC, < 1910)
 
     BOOST_TEST_TRAIT_TRUE((is_contiguous_range<X1>));
 

test/is_contiguous_range_test3.cpp

@@ -0,0 +1,25 @@
+// Copyright 2022 Peter Dimov.
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/container_hash/is_contiguous_range.hpp>
+#include <boost/core/lightweight_test_trait.hpp>
+#include <cstddef>
+
+struct X1
+{
+    char const* begin() const;
+    char const* end() const;
+    std::size_t size() const;
+
+    char data[16];
+};
+
+int main()
+{
+    using boost::container_hash::is_contiguous_range;
+
+    BOOST_TEST_TRAIT_FALSE((is_contiguous_range<X1>));
+
+    return boost::report_errors();
+}

test/is_described_class_test.cpp

@@ -0,0 +1,56 @@
+// Copyright 2022 Peter Dimov.
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/container_hash/is_described_class.hpp>
+#include <boost/describe/class.hpp>
+#include <boost/core/lightweight_test_trait.hpp>
+#include <string>
+
+struct X1
+{
+};
+
+struct X2
+{
+    int m;
+};
+
+struct Y1
+{
+};
+
+BOOST_DESCRIBE_STRUCT( Y1, (), () )
+
+struct Y2: Y1
+{
+    int m;
+};
+
+BOOST_DESCRIBE_STRUCT( Y2, (Y1), (m) )
+
+int main()
+{
+    using boost::container_hash::is_described_class;
+
+    BOOST_TEST_TRAIT_FALSE((is_described_class<void>));
+    BOOST_TEST_TRAIT_FALSE((is_described_class<int>));
+    BOOST_TEST_TRAIT_FALSE((is_described_class<X1>));
+    BOOST_TEST_TRAIT_FALSE((is_described_class<X2>));
+    BOOST_TEST_TRAIT_FALSE((is_described_class<int[2]>));
+    BOOST_TEST_TRAIT_FALSE((is_described_class<std::string>));
+
+#if defined(BOOST_DESCRIBE_CXX14)
+
+    BOOST_TEST_TRAIT_TRUE((is_described_class<Y1>));
+    BOOST_TEST_TRAIT_TRUE((is_described_class<Y2>));
+
+#else
+
+    BOOST_TEST_TRAIT_FALSE((is_described_class<Y1>));
+    BOOST_TEST_TRAIT_FALSE((is_described_class<Y2>));
+
+#endif
+
+    return boost::report_errors();
+}

test/is_described_class_test2.cpp

@@ -0,0 +1,35 @@
+// Copyright 2022 Peter Dimov.
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/type_traits/integral_constant.hpp>
+#include <boost/describe/class.hpp>
+
+struct X
+{
+};
+
+BOOST_DESCRIBE_STRUCT( X, (), () )
+
+namespace boost
+{
+namespace container_hash
+{
+
+template<class T> struct is_described_class;
+template<> struct is_described_class<X>: boost::false_type {};
+
+} // namespace container_hash
+} // namespace boost
+
+#include <boost/container_hash/is_described_class.hpp>
+#include <boost/core/lightweight_test_trait.hpp>
+
+int main()
+{
+    using boost::container_hash::is_described_class;
+
+    BOOST_TEST_TRAIT_FALSE((is_described_class<X>));
+
+    return boost::report_errors();
+}

test/is_described_class_test3.cpp

@@ -0,0 +1,31 @@
+// Copyright 2022 Peter Dimov.
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/container_hash/is_described_class.hpp>
+#include <boost/describe/class.hpp>
+#include <boost/core/lightweight_test_trait.hpp>
+
+union Y1
+{
+};
+
+BOOST_DESCRIBE_STRUCT( Y1, (), () )
+
+union Y2
+{
+    int m1;
+    float m2;
+};
+
+BOOST_DESCRIBE_STRUCT( Y2, (), (m1, m2) )
+
+int main()
+{
+    using boost::container_hash::is_described_class;
+
+    BOOST_TEST_TRAIT_FALSE((is_described_class<Y1>));
+    BOOST_TEST_TRAIT_FALSE((is_described_class<Y2>));
+
+    return boost::report_errors();
+}

test/is_tuple_like_test.cpp

@@ -0,0 +1,91 @@
+// Copyright 2017, 2022 Peter Dimov.
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#if defined(__clang__)
+# pragma clang diagnostic ignored "-Wmismatched-tags"
+#endif
+
+#include <boost/container_hash/is_tuple_like.hpp>
+#include <boost/core/lightweight_test_trait.hpp>
+#include <boost/config.hpp>
+#include <boost/config/workaround.hpp>
+#include <utility>
+
+struct X
+{
+};
+
+#if !defined(BOOST_NO_CXX11_HDR_TUPLE)
+
+#include <tuple>
+
+namespace user
+{
+
+struct Y
+{
+    int a;
+    int b;
+};
+
+template<std::size_t I> int& get( Y& v );
+template<std::size_t I> int const& get( Y const& v );
+
+template<> int& get<0>( Y& v )
+{
+    return v.a;
+}
+
+template<> int const& get<0>( Y const& v )
+{
+    return v.a;
+}
+
+template<> int& get<1>( Y& v )
+{
+    return v.b;
+}
+
+template<> int const& get<1>( Y const& v )
+{
+    return v.b;
+}
+
+} // namespace user
+
+namespace std
+{
+
+template<> struct tuple_size<user::Y>: std::integral_constant<std::size_t, 2>
+{
+};
+
+} // namespace std
+
+#endif // #if !defined(BOOST_NO_CXX11_HDR_TUPLE)
+
+int main()
+{
+    using boost::container_hash::is_tuple_like;
+
+    BOOST_TEST_TRAIT_FALSE((is_tuple_like<void>));
+    BOOST_TEST_TRAIT_FALSE((is_tuple_like<int>));
+    BOOST_TEST_TRAIT_FALSE((is_tuple_like<X>));
+    BOOST_TEST_TRAIT_FALSE((is_tuple_like<int[2]>));
+
+#if !defined(BOOST_NO_CXX11_HDR_TUPLE) && !BOOST_WORKAROUND(BOOST_MSVC, <= 1800)
+
+    BOOST_TEST_TRAIT_TRUE((is_tuple_like< std::pair<int, X> >));
+
+    BOOST_TEST_TRAIT_TRUE((is_tuple_like< std::tuple<> >));
+    BOOST_TEST_TRAIT_TRUE((is_tuple_like< std::tuple<X> >));
+    BOOST_TEST_TRAIT_TRUE((is_tuple_like< std::tuple<X, X> >));
+    BOOST_TEST_TRAIT_TRUE((is_tuple_like< std::tuple<X, X, X> >));
+
+    BOOST_TEST_TRAIT_TRUE((is_tuple_like<user::Y>));
+
+#endif
+
+    return boost::report_errors();
+}