From 8b77644ea005ace9ee5af08a6f82aa8e235e2710 Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Sat, 20 Jan 2018 17:30:33 +0000
Subject: [PATCH 01/20] Support std::string_view

---
 include/boost/container_hash/hash/hash.hpp | 55 ++++++++++++++++++++++
 test/hash_string_test.cpp                  | 37 +++++++++++++++
 2 files changed, 92 insertions(+)

diff --git a/include/boost/container_hash/hash/hash.hpp b/include/boost/container_hash/hash/hash.hpp
index 21296f3..c1b873e 100644
--- a/include/boost/container_hash/hash/hash.hpp
+++ b/include/boost/container_hash/hash/hash.hpp
@@ -58,6 +58,33 @@
 #   define BOOST_FUNCTIONAL_HASH_ROTL32(x, r) (x << r) | (x >> (32 - r))
 #endif
 
+// Detect whether standard library has <string_view>.
+
+#if !defined(BOOST_HASH_HAS_STRING_VIEW) && defined(__has_include)
+#   if __has_include(<string_view>)
+#       if defined(BOOST_MSVC)
+            // On Visual C++ the header exists, but causes an
+            // error if it isn't in C++17 mode.
+#           if defined(_HAS_CXX17) && _HAS_CXX17
+#               define BOOST_HASH_HAS_STRING_VIEW 1
+#               include <string_view>
+#           endif
+#       else
+#           include <string_view>
+#           if defined(__cpp_lib_string_view) && __cpp_lib_string_view >= 201603
+#               define BOOST_HASH_HAS_STRING_VIEW 1
+#           endif
+#       endif
+#   endif
+#endif
+
+#if !defined(BOOST_HASH_HAS_STRING_VIEW)
+#   define BOOST_HASH_HAS_STRING_VIEW 0
+#endif
+
+#if BOOST_HASH_HAS_STRING_VIEW
+#endif
+
 namespace boost
 {
     namespace hash_detail
@@ -176,6 +203,12 @@ namespace boost
     std::size_t hash_value(
         std::basic_string<Ch, std::BOOST_HASH_CHAR_TRAITS<Ch>, A> const&);
 
+#if BOOST_HASH_HAS_STRING_VIEW
+    template <class Ch>
+    std::size_t hash_value(
+        std::basic_string_view<Ch, std::BOOST_HASH_CHAR_TRAITS<Ch> > const&);
+#endif
+
     template <typename T>
     typename boost::hash_detail::float_numbers<T>::type hash_value(T);
 
@@ -410,6 +443,15 @@ namespace boost
         return hash_range(v.begin(), v.end());
     }
 
+#if BOOST_HASH_HAS_STRING_VIEW
+    template <class Ch>
+    inline std::size_t hash_value(
+        std::basic_string_view<Ch, std::BOOST_HASH_CHAR_TRAITS<Ch> > const& v)
+    {
+        return hash_range(v.begin(), v.end());
+    }
+#endif
+
     template <typename T>
     typename boost::hash_detail::float_numbers<T>::type hash_value(T v)
     {
@@ -494,6 +536,19 @@ namespace boost
     BOOST_HASH_SPECIALIZE_REF(std::basic_string<char32_t>)
 #endif
 
+#if BOOST_HASH_HAS_STRING_VIEW
+    BOOST_HASH_SPECIALIZE_REF(std::string_view)
+#   if !defined(BOOST_NO_STD_WSTRING) && !defined(BOOST_NO_INTRINSIC_WCHAR_T)
+    BOOST_HASH_SPECIALIZE_REF(std::wstring_view)
+#   endif
+#   if !defined(BOOST_NO_CXX11_CHAR16_T)
+    BOOST_HASH_SPECIALIZE_REF(std::basic_string_view<char16_t>)
+#   endif
+#   if !defined(BOOST_NO_CXX11_CHAR32_T)
+    BOOST_HASH_SPECIALIZE_REF(std::basic_string_view<char32_t>)
+#   endif
+#endif
+
 #if !defined(BOOST_NO_LONG_LONG)
     BOOST_HASH_SPECIALIZE(boost::long_long_type)
     BOOST_HASH_SPECIALIZE(boost::ulong_long_type)
diff --git a/test/hash_string_test.cpp b/test/hash_string_test.cpp
index f84eb74..712c639 100644
--- a/test/hash_string_test.cpp
+++ b/test/hash_string_test.cpp
@@ -130,6 +130,37 @@ void u32string_tests()
 }
 #endif
 
+template <typename StringType>
+void generic_string_tests(StringType*)
+{
+    std::string x1(1, '\0');
+    std::string x2(2, '\0');
+    std::string x3(3, '\0');
+    std::string x4(10, '\0');
+    std::string x5 = x2 + "hello" + x2;
+
+    StringType strings[] = {
+        "",
+        "hello",
+        x1,
+        x2,
+        x3,
+        x4,
+        x5
+    };
+
+    std::size_t const strings_length = sizeof(strings) / sizeof(StringType);
+    boost::hash<StringType> hash;
+
+    for (std::size_t i = 0; i < strings_length; ++i) {
+        std::size_t hash_i = hash(strings[i]);
+        for (std::size_t j = 0; j < strings_length; ++j) {
+            std::size_t hash_j = hash(strings[j]);
+            BOOST_TEST((hash_i == hash_j) == (i == j));
+        }
+    }
+}
+
 int main()
 {
     string_tests();
@@ -143,5 +174,11 @@ int main()
 #if !defined(BOOST_NO_CXX11_CHAR32_T)
     u32string_tests();
 #endif
+
+    generic_string_tests((std::string*) 0);
+#if BOOST_HASH_HAS_STRING_VIEW
+    generic_string_tests((std::string_view*) 0);
+#endif
+
     return boost::report_errors();
 }

From 3521c417b59b657e9f845f41b4f844fd0d462e3a Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Sat, 20 Jan 2018 17:30:58 +0000
Subject: [PATCH 02/20] Small program to write out hash config info

---
 test/Jamfile.v2    |  1 +
 test/hash_info.cpp | 15 +++++++++++++++
 2 files changed, 16 insertions(+)
 create mode 100644 test/hash_info.cpp

diff --git a/test/Jamfile.v2 b/test/Jamfile.v2
index dd2b977..ed2fc49 100644
--- a/test/Jamfile.v2
+++ b/test/Jamfile.v2
@@ -20,6 +20,7 @@ project hash-tests
 
 test-suite container_hash/hash
     :
+        [ run hash_info.cpp : : : <test-info>always_show_run_output ]
         [ compile check_float_funcs.cpp ]
         [ run hash_fwd_test_1.cpp ]
         [ run hash_fwd_test_2.cpp ]
diff --git a/test/hash_info.cpp b/test/hash_info.cpp
new file mode 100644
index 0000000..25b942a
--- /dev/null
+++ b/test/hash_info.cpp
@@ -0,0 +1,15 @@
+
+// Copyright 2017 Daniel James.
+// 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)
+
+// Not a test, just a small program to write out configuration info
+
+#include <boost/container_hash/hash.hpp>
+#include <iostream>
+
+int main() {
+    std::cout << "BOOST_HASH_HAS_STRING_VIEW: "
+        << BOOST_HASH_HAS_STRING_VIEW
+        << std::endl;
+}

From def7a785a546e25600c90782b8984e1adde9709b Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Sat, 20 Jan 2018 18:39:46 +0000
Subject: [PATCH 03/20] Remove some pointless code

---
 include/boost/container_hash/hash/hash.hpp | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/include/boost/container_hash/hash/hash.hpp b/include/boost/container_hash/hash/hash.hpp
index c1b873e..961dda9 100644
--- a/include/boost/container_hash/hash/hash.hpp
+++ b/include/boost/container_hash/hash/hash.hpp
@@ -82,9 +82,6 @@
 #   define BOOST_HASH_HAS_STRING_VIEW 0
 #endif
 
-#if BOOST_HASH_HAS_STRING_VIEW
-#endif
-
 namespace boost
 {
     namespace hash_detail

From b5c3b5d00afcae83db1b669591caeeecc109eff6 Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Sat, 20 Jan 2018 21:53:03 +0000
Subject: [PATCH 04/20] Write out __cplusplus in hash_info

---
 test/hash_info.cpp | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/test/hash_info.cpp b/test/hash_info.cpp
index 25b942a..83f74a1 100644
--- a/test/hash_info.cpp
+++ b/test/hash_info.cpp
@@ -9,6 +9,11 @@
 #include <iostream>
 
 int main() {
+#if defined(__cplusplus)
+    std::cout << "__cplusplus: "
+        << __cplusplus
+        << std::endl;
+#endif
     std::cout << "BOOST_HASH_HAS_STRING_VIEW: "
         << BOOST_HASH_HAS_STRING_VIEW
         << std::endl;

From 5c4edf4d7d6dc36917a150298499158a4c20ae99 Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Sat, 20 Jan 2018 21:53:36 +0000
Subject: [PATCH 05/20] Fix string_view include on gcc 7.2

If it's included in anything earlier than c++-1z it errors.
---
 include/boost/container_hash/hash/hash.hpp | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/include/boost/container_hash/hash/hash.hpp b/include/boost/container_hash/hash/hash.hpp
index 961dda9..f648205 100644
--- a/include/boost/container_hash/hash/hash.hpp
+++ b/include/boost/container_hash/hash/hash.hpp
@@ -69,11 +69,9 @@
 #               define BOOST_HASH_HAS_STRING_VIEW 1
 #               include <string_view>
 #           endif
-#       else
+#       elif defined(__cplusplus) && __cplusplus >= 201703
 #           include <string_view>
-#           if defined(__cpp_lib_string_view) && __cpp_lib_string_view >= 201603
-#               define BOOST_HASH_HAS_STRING_VIEW 1
-#           endif
+#           define BOOST_HASH_HAS_STRING_VIEW 1
 #       endif
 #   endif
 #endif

From f81ee167c5c10d418cdefcf10e4f43ea69be32e4 Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Sun, 21 Jan 2018 11:10:03 +0000
Subject: [PATCH 06/20] Add Visual C++ info to hash_info

---
 test/hash_info.cpp | 61 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 61 insertions(+)

diff --git a/test/hash_info.cpp b/test/hash_info.cpp
index 83f74a1..21425c3 100644
--- a/test/hash_info.cpp
+++ b/test/hash_info.cpp
@@ -7,8 +7,69 @@
 
 #include <boost/container_hash/hash.hpp>
 #include <iostream>
+#include <algorithm>
+
+#if defined(BOOST_MSVC)
+
+struct msvc_version {
+    std::size_t version;
+    char const* description;
+
+    bool operator<(std::size_t v) const {
+        return version < v;
+    }
+    friend bool operator<(std::size_t v1, msvc_version const& v2) {
+        return v1 < v2.version;
+    }
+};
+
+void write_compiler_info() {
+    // From:
+    // https://en.wikipedia.org/wiki/Microsoft_Visual_C%2B%2B
+    // https://blogs.msdn.microsoft.com/vcblog/2017/11/15/side-by-side-minor-version-msvc-toolsets-in-visual-studio-2017/
+    msvc_version versions[] = {
+        {0, "Old Visual C++"},
+        {1000, "Visual C++ 4.x, VS4.0?"},
+        {1100, "Visual C++ 5.0, VS97"},
+        {1200, "Visual C++ 6.0, VS6.0"},
+        {1300, "Visual C++ 7.0, VS.NET 2002"},
+        {1310, "Visual C++ 7.1, VS.NET 2003"},
+        {1400, "Visual C++ 8.0, VS2005"},
+        {1500, "Visual C++ 9.0, VS2008"},
+        {1600, "Visual C++ 10.0, VS2010"},
+        {1700, "Visual C++ 11.0, VS2012"},
+        {1800, "Visual C++ 12.0, VS2013"},
+        {1900, "Visual C++ 14.00, VS2015"},
+        {1910, "Visual C++ 14.10, VS2017 15.1/2"},
+        {1911, "Visual C++ 14.11, VS2017 15.3/4"},
+        {1912, "Visual C++ 14.12, VS2017 15.5"}
+    };
+
+    std::size_t msvc = BOOST_MSVC;
+    msvc_version* v = std::upper_bound(versions,
+        versions + sizeof(versions) / sizeof(*versions),
+        msvc) - 1;
+    std::size_t difference = BOOST_MSVC - v->version;
+
+    std::cout << v->description << std::endl;
+    if (difference) {
+        std::cout << "+" << difference << std::endl;
+    }
+#if defined(_HAS_CXX17) && _HAS_CXX17
+    std::cout << "C++17 mode" << std::endl;
+#endif
+}
+
+#else
+
+void write_compiler_info() {
+}
+
+#endif
 
 int main() {
+    write_compiler_info();
+
 #if defined(__cplusplus)
     std::cout << "__cplusplus: "
         << __cplusplus

From 42bb81befac23361240e74b4857c98f635112bab Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Sun, 21 Jan 2018 13:44:50 +0000
Subject: [PATCH 07/20] Support std::error_code and std::error_condition

---
 include/boost/container_hash/hash/hash.hpp | 31 ++++++++++--
 test/Jamfile.v2                            |  1 +
 test/hash_info.cpp                         | 13 +++++
 test/hash_system_error_test.cpp            | 55 ++++++++++++++++++++++
 4 files changed, 97 insertions(+), 3 deletions(-)
 create mode 100644 test/hash_system_error_test.cpp

diff --git a/include/boost/container_hash/hash/hash.hpp b/include/boost/container_hash/hash/hash.hpp
index f648205..f7cd21d 100644
--- a/include/boost/container_hash/hash/hash.hpp
+++ b/include/boost/container_hash/hash/hash.hpp
@@ -5,7 +5,7 @@
 
 //  Based on Peter Dimov's proposal
 //  http://www.open-std.org/JTC1/SC22/WG21/docs/papers/2005/n1756.pdf
-//  issue 6.18. 
+//  issue 6.18.
 //
 //  This also contains public domain code from MurmurHash. From the
 //  MurmurHash header:
@@ -34,6 +34,10 @@
 #include <typeindex>
 #endif
 
+#if !defined(BOOST_NO_CXX11_HDR_SYSTEM_ERROR)
+#include <system_error>
+#endif
+
 #if defined(BOOST_MSVC)
 #pragma warning(push)
 
@@ -211,6 +215,11 @@ namespace boost
     std::size_t hash_value(std::type_index);
 #endif
 
+#if !defined(BOOST_NO_CXX11_HDR_SYSTEM_ERROR)
+    std::size_t hash_value(std::error_code const&);
+    std::size_t hash_value(std::error_condition const&);
+#endif
+
     // Implementation
 
     namespace hash_detail
@@ -460,14 +469,30 @@ namespace boost
     }
 #endif
 
+#if !defined(BOOST_NO_CXX11_HDR_SYSTEM_ERROR)
+    inline std::size_t hash_value(std::error_code const& v) {
+        std::size_t seed = 0;
+        hash_combine(seed, v.value());
+        hash_combine(seed, &v.category());
+        return seed;
+    }
+
+    inline std::size_t hash_value(std::error_condition const& v) {
+        std::size_t seed = 0;
+        hash_combine(seed, v.value());
+        hash_combine(seed, &v.category());
+        return seed;
+    }
+#endif
+
     //
     // boost::hash
     //
-    
+
     // Define the specializations required by the standard. The general purpose
     // boost::hash is defined later in extensions.hpp if
     // BOOST_HASH_NO_EXTENSIONS is not defined.
-    
+
     // BOOST_HASH_SPECIALIZE - define a specialization for a type which is
     // passed by copy.
     //
diff --git a/test/Jamfile.v2 b/test/Jamfile.v2
index ed2fc49..6b11b7f 100644
--- a/test/Jamfile.v2
+++ b/test/Jamfile.v2
@@ -44,6 +44,7 @@ test-suite container_hash/hash
         [ run hash_map_test.cpp ]
         [ run hash_complex_test.cpp ]
         [ run hash_type_index_test.cpp ]
+        [ run hash_system_error_test.cpp ]
         [ run hash_std_array_test.cpp ]
         [ run hash_std_tuple_test.cpp ]
         [ run hash_std_smart_ptr_test.cpp ]
diff --git a/test/hash_info.cpp b/test/hash_info.cpp
index 21425c3..8a906c3 100644
--- a/test/hash_info.cpp
+++ b/test/hash_info.cpp
@@ -78,4 +78,17 @@ int main() {
     std::cout << "BOOST_HASH_HAS_STRING_VIEW: "
         << BOOST_HASH_HAS_STRING_VIEW
         << std::endl;
+
+#if defined(BOOST_NO_CXX11_HDR_TYPEINDEX)
+    std::cout << "No <typeindex>" << std::endl;
+#else
+    std::cout << "<typeindex>" << std::endl;
+#endif
+
+#if defined(BOOST_NO_CXX11_HDR_SYSTEM_ERROR)
+    std::cout << "No <system_error>" << std::endl;
+#else
+    std::cout << "<system_error>" << std::endl;
+#endif
+
 }
diff --git a/test/hash_system_error_test.cpp b/test/hash_system_error_test.cpp
new file mode 100644
index 0000000..71eb714
--- /dev/null
+++ b/test/hash_system_error_test.cpp
@@ -0,0 +1,55 @@
+
+// Copyright 2018 Daniel James
+// 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)
+
+#include "./config.hpp"
+
+#ifndef BOOST_HASH_TEST_STD_INCLUDES
+#  include <boost/container_hash/hash.hpp>
+#endif
+#include <boost/config.hpp>
+#include <boost/core/lightweight_test.hpp>
+
+#if !defined(BOOST_NO_CXX11_HDR_SYSTEM_ERROR)
+
+#include <system_error>
+
+void test_error_code()
+{
+    std::error_code err1a = std::make_error_code(std::errc::address_family_not_supported);
+    std::error_code err1b = std::make_error_code(std::errc::address_family_not_supported);
+    std::error_code err2 = std::make_error_code(std::errc::address_in_use);
+
+    boost::hash<std::error_code> hasher;
+
+    BOOST_TEST(hasher(err1a) == hasher(err1a));
+    BOOST_TEST(hasher(err1a) == hasher(err1b));
+    BOOST_TEST(hasher(err1a) != hasher(err2));
+}
+
+void test_error_condition()
+{
+    std::error_condition err1a = std::make_error_condition(std::errc::address_family_not_supported);
+    std::error_condition err1b = std::make_error_condition(std::errc::address_family_not_supported);
+    std::error_condition err2 = std::make_error_condition(std::errc::address_in_use);
+
+    boost::hash<std::error_condition> hasher;
+
+    BOOST_TEST(hasher(err1a) == hasher(err1a));
+    BOOST_TEST(hasher(err1a) == hasher(err1b));
+    BOOST_TEST(hasher(err1a) != hasher(err2));
+}
+
+#endif
+
+int main()
+{
+#if !defined(BOOST_NO_CXX11_HDR_SYSTEM_ERROR)
+    test_error_code();
+    test_error_condition();
+#else
+    BOOST_LIGHTWEIGHT_TEST_OSTREAM << "<system_error> not available." << std::endl;
+#endif
+    return boost::report_errors();
+}

From b9ae7e7fb67e4c68ee9e106b517e16972cde5869 Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Sun, 21 Jan 2018 18:21:46 +0000
Subject: [PATCH 08/20] Clean up header detection for more headers + add
 optional

---
 include/boost/container_hash/hash/hash.hpp | 45 +++++++++++++++-------
 test/hash_info.cpp                         | 12 ++++--
 2 files changed, 41 insertions(+), 16 deletions(-)

diff --git a/include/boost/container_hash/hash/hash.hpp b/include/boost/container_hash/hash/hash.hpp
index f7cd21d..41cab8a 100644
--- a/include/boost/container_hash/hash/hash.hpp
+++ b/include/boost/container_hash/hash/hash.hpp
@@ -62,21 +62,28 @@
 #   define BOOST_FUNCTIONAL_HASH_ROTL32(x, r) (x << r) | (x >> (32 - r))
 #endif
 
-// Detect whether standard library has <string_view>.
+// Detect whether standard library has C++17 headers
 
-#if !defined(BOOST_HASH_HAS_STRING_VIEW) && defined(__has_include)
-#   if __has_include(<string_view>)
-#       if defined(BOOST_MSVC)
-            // On Visual C++ the header exists, but causes an
-            // error if it isn't in C++17 mode.
-#           if defined(_HAS_CXX17) && _HAS_CXX17
-#               define BOOST_HASH_HAS_STRING_VIEW 1
-#               include <string_view>
-#           endif
-#       elif defined(__cplusplus) && __cplusplus >= 201703
-#           include <string_view>
-#           define BOOST_HASH_HAS_STRING_VIEW 1
+#if !defined(BOOST_HASH_CXX17)
+#   if defined(BOOST_MSVC)
+#       if defined(_HAS_CXX17) && _HAS_CXX17
+#           define BOOST_HASH_CXX17 1
 #       endif
+#   elif defined(__cplusplus) && __cplusplus >= 201703
+#       define BOOST_HASH_CXX17 1
+#   endif
+#endif
+
+#if !defined(BOOST_HASH_CXX17)
+#   define BOOST_HASH_CXX17 0
+#endif
+
+#if BOOST_HASH_CXX17 && defined(__has_include)
+#   if !defined(BOOST_HASH_HAS_STRING_VIEW) && __has_include(<string_view>)
+#       define BOOST_HASH_HAS_STRING_VIEW 1
+#   endif
+#   if !defined(BOOST_HASH_HAS_OPTIONAL) && __has_include(<optional>)
+#       define BOOST_HASH_HAS_OPTIONAL 1
 #   endif
 #endif
 
@@ -84,6 +91,18 @@
 #   define BOOST_HASH_HAS_STRING_VIEW 0
 #endif
 
+#if !defined(BOOST_HASH_HAS_OPTIONAL)
+#   define BOOST_HASH_HAS_OPTIONAL 0
+#endif
+
+#if BOOST_HASH_HAS_STRING_VIEW
+#   include <string_view>
+#endif
+
+#if BOOST_HASH_HAS_OPTIONAL
+#   include <optional>
+#endif
+
 namespace boost
 {
     namespace hash_detail
diff --git a/test/hash_info.cpp b/test/hash_info.cpp
index 8a906c3..c7b8ec8 100644
--- a/test/hash_info.cpp
+++ b/test/hash_info.cpp
@@ -55,9 +55,6 @@ void write_compiler_info() {
     if (difference) {
         std::cout << "+" << difference << std::endl;
     }
-#if defined(_HAS_CXX17) && _HAS_CXX17
-    std::cout << "C++17 mode" << std::endl;
-#endif
 }
 
 #else
@@ -75,10 +72,19 @@ int main() {
         << __cplusplus
         << std::endl;
 #endif
+
+    std::cout << "BOOST_HASH_CXX17: "
+        << BOOST_HASH_CXX17
+        << std::endl;
+
     std::cout << "BOOST_HASH_HAS_STRING_VIEW: "
         << BOOST_HASH_HAS_STRING_VIEW
         << std::endl;
 
+    std::cout << "BOOST_HASH_HAS_OPTIONAL: "
+        << BOOST_HASH_HAS_OPTIONAL
+        << std::endl;
+
 #if defined(BOOST_NO_CXX11_HDR_TYPEINDEX)
     std::cout << "No <typeindex>" << std::endl;
 #else

From ddc05d17dff6cab3edac55ddd965853242c46868 Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Sun, 21 Jan 2018 18:38:35 +0000
Subject: [PATCH 09/20] std::optional support

---
 include/boost/container_hash/hash/hash.hpp | 34 +++++++++++
 test/Jamfile.v2                            |  1 +
 test/hash_optional_test.cpp                | 70 ++++++++++++++++++++++
 3 files changed, 105 insertions(+)
 create mode 100644 test/hash_optional_test.cpp

diff --git a/include/boost/container_hash/hash/hash.hpp b/include/boost/container_hash/hash/hash.hpp
index 41cab8a..a524aa2 100644
--- a/include/boost/container_hash/hash/hash.hpp
+++ b/include/boost/container_hash/hash/hash.hpp
@@ -230,6 +230,11 @@ namespace boost
     template <typename T>
     typename boost::hash_detail::float_numbers<T>::type hash_value(T);
 
+#if BOOST_HASH_HAS_OPTIONAL
+    template <typename T>
+    std::size_t hash_value(std::optional<T> const&);
+#endif
+
 #if !defined(BOOST_NO_CXX11_HDR_TYPEINDEX)
     std::size_t hash_value(std::type_index);
 #endif
@@ -481,6 +486,19 @@ namespace boost
         return boost::hash_detail::float_hash_value(v);
     }
 
+#if BOOST_HASH_HAS_OPTIONAL
+    template <typename T>
+    inline std::size_t hash_value(std::optional<T> const& v) {
+        if (!v) {
+            // Arbitray value for empty optional.
+            return 0x12345678;
+        } else {
+            boost::hash<T> hf;
+            return hf(*v);
+        }
+    }
+#endif
+
 #if !defined(BOOST_NO_CXX11_HDR_TYPEINDEX)
     inline std::size_t hash_value(std::type_index v)
     {
@@ -540,6 +558,16 @@ namespace boost
         } \
     };
 
+#define BOOST_HASH_SPECIALIZE_TEMPLATE_REF(type) \
+    struct hash<type> \
+         : public boost::hash_detail::hash_base<type> \
+    { \
+        std::size_t operator()(type const& v) const \
+        { \
+            return boost::hash_value(v); \
+        } \
+    };
+
     BOOST_HASH_SPECIALIZE(bool)
     BOOST_HASH_SPECIALIZE(char)
     BOOST_HASH_SPECIALIZE(signed char)
@@ -598,12 +626,18 @@ namespace boost
     BOOST_HASH_SPECIALIZE(boost::uint128_type)
 #endif
 
+#if BOOST_HASH_HAS_OPTIONAL
+    template <typename T>
+    BOOST_HASH_SPECIALIZE_TEMPLATE_REF(std::optional<T>)
+#endif
+
 #if !defined(BOOST_NO_CXX11_HDR_TYPEINDEX)
     BOOST_HASH_SPECIALIZE(std::type_index)
 #endif
 
 #undef BOOST_HASH_SPECIALIZE
 #undef BOOST_HASH_SPECIALIZE_REF
+#undef BOOST_HASH_SPECIALIZE_TEMPLATE_REF
 
 // Specializing boost::hash for pointers.
 
diff --git a/test/Jamfile.v2 b/test/Jamfile.v2
index 6b11b7f..96c3b67 100644
--- a/test/Jamfile.v2
+++ b/test/Jamfile.v2
@@ -43,6 +43,7 @@ test-suite container_hash/hash
         [ run hash_set_test.cpp ]
         [ run hash_map_test.cpp ]
         [ run hash_complex_test.cpp ]
+        [ run hash_optional_test.cpp ]
         [ run hash_type_index_test.cpp ]
         [ run hash_system_error_test.cpp ]
         [ run hash_std_array_test.cpp ]
diff --git a/test/hash_optional_test.cpp b/test/hash_optional_test.cpp
new file mode 100644
index 0000000..4469395
--- /dev/null
+++ b/test/hash_optional_test.cpp
@@ -0,0 +1,70 @@
+
+// Copyright 2018 Daniel James
+// 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)
+
+#include "./config.hpp"
+
+#ifndef BOOST_HASH_TEST_STD_INCLUDES
+#  include <boost/container_hash/hash.hpp>
+#endif
+#include <boost/config.hpp>
+#include <boost/core/lightweight_test.hpp>
+
+#if BOOST_HASH_HAS_OPTIONAL
+
+#include <optional>
+#include <string>
+
+void test_optional_int()
+{
+    std::optional<int> x1a;
+    std::optional<int> x1b;
+    std::optional<int> x2a(10);
+    std::optional<int> x2b(x2a);
+    std::optional<int> x3(20);
+
+    boost::hash<std::optional<int> > hasher;
+
+    BOOST_TEST(hasher(x1a) == hasher(x1a));
+    BOOST_TEST(hasher(x1a) == hasher(x1b));
+    BOOST_TEST(hasher(x1a) != hasher(x2a));
+    BOOST_TEST(hasher(x1a) != hasher(x3));
+    BOOST_TEST(hasher(x2a) == hasher(x2a));
+    BOOST_TEST(hasher(x2b) == hasher(x2b));
+    BOOST_TEST(hasher(x2a) != hasher(x3));
+    BOOST_TEST(hasher(x3) == hasher(x3));
+}
+
+void test_optional_string()
+{
+    std::optional<std::string> x1a;
+    std::optional<std::string> x1b;
+    std::optional<std::string> x2a("10");
+    std::optional<std::string> x2b(x2a);
+    std::optional<std::string> x3("20");
+
+    boost::hash<std::optional<std::string> > hasher;
+
+    BOOST_TEST(hasher(x1a) == hasher(x1a));
+    BOOST_TEST(hasher(x1a) == hasher(x1b));
+    BOOST_TEST(hasher(x1a) != hasher(x2a));
+    BOOST_TEST(hasher(x1a) != hasher(x3));
+    BOOST_TEST(hasher(x2a) == hasher(x2a));
+    BOOST_TEST(hasher(x2b) == hasher(x2b));
+    BOOST_TEST(hasher(x2a) != hasher(x3));
+    BOOST_TEST(hasher(x3) == hasher(x3));
+}
+
+#endif
+
+int main()
+{
+#if BOOST_HASH_HAS_OPTIONAL
+    test_optional_int();
+    test_optional_string();
+#else
+    BOOST_LIGHTWEIGHT_TEST_OSTREAM << "<optional> not available." << std::endl;
+#endif
+    return boost::report_errors();
+}

From 4d9f4388239f768fae1a6224c6541af7ec05c9d5 Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Sun, 21 Jan 2018 19:18:58 +0000
Subject: [PATCH 10/20] std::variant, std::monostate support

---
 include/boost/container_hash/hash/hash.hpp |  38 ++++++++
 test/Jamfile.v2                            |   1 +
 test/hash_info.cpp                         |   4 +
 test/hash_variant_test.cpp                 | 100 +++++++++++++++++++++
 4 files changed, 143 insertions(+)
 create mode 100644 test/hash_variant_test.cpp

diff --git a/include/boost/container_hash/hash/hash.hpp b/include/boost/container_hash/hash/hash.hpp
index a524aa2..4b10870 100644
--- a/include/boost/container_hash/hash/hash.hpp
+++ b/include/boost/container_hash/hash/hash.hpp
@@ -85,6 +85,9 @@
 #   if !defined(BOOST_HASH_HAS_OPTIONAL) && __has_include(<optional>)
 #       define BOOST_HASH_HAS_OPTIONAL 1
 #   endif
+#   if !defined(BOOST_HASH_HAS_VARIANT) && __has_include(<variant>)
+#       define BOOST_HASH_HAS_VARIANT 1
+#   endif
 #endif
 
 #if !defined(BOOST_HASH_HAS_STRING_VIEW)
@@ -95,6 +98,10 @@
 #   define BOOST_HASH_HAS_OPTIONAL 0
 #endif
 
+#if !defined(BOOST_HASH_HAS_VARIANT)
+#   define BOOST_HASH_HAS_VARIANT 0
+#endif
+
 #if BOOST_HASH_HAS_STRING_VIEW
 #   include <string_view>
 #endif
@@ -103,6 +110,10 @@
 #   include <optional>
 #endif
 
+#if BOOST_HASH_HAS_VARIANT
+#   include <variant>
+#endif
+
 namespace boost
 {
     namespace hash_detail
@@ -235,6 +246,12 @@ namespace boost
     std::size_t hash_value(std::optional<T> const&);
 #endif
 
+#if BOOST_HASH_HAS_VARIANT
+    std::size_t hash_value(std::monostate);
+    template <typename... Types>
+    std::size_t hash_value(std::variant<Types...> const&);
+#endif
+
 #if !defined(BOOST_NO_CXX11_HDR_TYPEINDEX)
     std::size_t hash_value(std::type_index);
 #endif
@@ -499,6 +516,21 @@ namespace boost
     }
 #endif
 
+#if BOOST_HASH_HAS_VARIANT
+    std::size_t hash_value(std::monostate) {
+        return 0x87654321;
+    }
+
+    template <typename... Types>
+    inline std::size_t hash_value(std::variant<Types...> const& v) {
+        std::size_t seed = 0;
+        hash_combine(seed, v.index());
+        std::visit([&seed](auto&& x) { hash_combine(seed, x); }, v);
+        return seed;
+    }
+#endif
+
+
 #if !defined(BOOST_NO_CXX11_HDR_TYPEINDEX)
     inline std::size_t hash_value(std::type_index v)
     {
@@ -631,6 +663,12 @@ namespace boost
     BOOST_HASH_SPECIALIZE_TEMPLATE_REF(std::optional<T>)
 #endif
 
+#if !defined(BOOST_HASH_HAS_VARIANT)
+    template <typename... T>
+    BOOST_HASH_SPECIALIZE_TEMPLATE_REF(std::variant<T...>)
+    BOOST_HASH_SPECIALIZE(std::monostate)
+#endif
+
 #if !defined(BOOST_NO_CXX11_HDR_TYPEINDEX)
     BOOST_HASH_SPECIALIZE(std::type_index)
 #endif
diff --git a/test/Jamfile.v2 b/test/Jamfile.v2
index 96c3b67..a9dddfb 100644
--- a/test/Jamfile.v2
+++ b/test/Jamfile.v2
@@ -44,6 +44,7 @@ test-suite container_hash/hash
         [ run hash_map_test.cpp ]
         [ run hash_complex_test.cpp ]
         [ run hash_optional_test.cpp ]
+        [ run hash_variant_test.cpp ]
         [ run hash_type_index_test.cpp ]
         [ run hash_system_error_test.cpp ]
         [ run hash_std_array_test.cpp ]
diff --git a/test/hash_info.cpp b/test/hash_info.cpp
index c7b8ec8..7159d1f 100644
--- a/test/hash_info.cpp
+++ b/test/hash_info.cpp
@@ -85,6 +85,10 @@ int main() {
         << BOOST_HASH_HAS_OPTIONAL
         << std::endl;
 
+    std::cout << "BOOST_HASH_HAS_VARIANT: "
+        << BOOST_HASH_HAS_VARIANT
+        << std::endl;
+
 #if defined(BOOST_NO_CXX11_HDR_TYPEINDEX)
     std::cout << "No <typeindex>" << std::endl;
 #else
diff --git a/test/hash_variant_test.cpp b/test/hash_variant_test.cpp
new file mode 100644
index 0000000..80f317a
--- /dev/null
+++ b/test/hash_variant_test.cpp
@@ -0,0 +1,100 @@
+
+// Copyright 2018 Daniel James
+// 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)
+
+#include "./config.hpp"
+
+#ifndef BOOST_HASH_TEST_STD_INCLUDES
+#  include <boost/container_hash/hash.hpp>
+#endif
+#include <boost/config.hpp>
+#include <boost/core/lightweight_test.hpp>
+
+#if BOOST_HASH_HAS_VARIANT
+
+#include <variant>
+#include <string>
+
+void test_monostate()
+{
+    std::monostate x1;
+    std::monostate x2;
+
+    boost::hash<std::monostate> hasher;
+
+    BOOST_TEST(hasher(x1) == hasher(x2));
+}
+
+void test_variant_int()
+{
+    std::variant<std::monostate, int> x1a;
+    std::variant<std::monostate, int> x1b;
+    std::variant<std::monostate, int> x2a(10);
+    std::variant<std::monostate, int> x2b(x2a);
+    std::variant<std::monostate, int> x3(20);
+
+    boost::hash<std::variant<std::monostate, int> > hasher;
+
+    BOOST_TEST(hasher(x1a) == hasher(x1a));
+    BOOST_TEST(hasher(x1a) == hasher(x1b));
+    BOOST_TEST(hasher(x1a) != hasher(x2a));
+    BOOST_TEST(hasher(x1a) != hasher(x3));
+    BOOST_TEST(hasher(x2a) == hasher(x2a));
+    BOOST_TEST(hasher(x2b) == hasher(x2b));
+    BOOST_TEST(hasher(x2a) != hasher(x3));
+    BOOST_TEST(hasher(x3) == hasher(x3));
+}
+
+struct custom1 {
+    int value;
+    friend std::size_t hash_value(custom1 v) { return v.value; }
+};
+
+struct custom2 {
+    int value;
+    friend std::size_t hash_value(custom2 v) { return v.value; }
+};
+
+void test_variant_unique_types()
+{
+    custom1 x11 = { 0 };
+    custom1 x12 = { 1 };
+    custom2 x21 = { 0 };
+    custom2 x22 = { 1 };
+
+    boost::hash<custom1> hasher1;
+    boost::hash<custom2> hasher2;
+
+    BOOST_TEST(hasher1(x11) == hasher2(x21));
+    BOOST_TEST(hasher1(x11) != hasher2(x22));
+    BOOST_TEST(hasher1(x12) != hasher2(x21));
+    BOOST_TEST(hasher1(x12) == hasher2(x22));
+
+    typedef std::variant<custom1, custom2> variant_type;
+
+    variant_type y11(x11);
+    variant_type y12(x12);
+    variant_type y21(x21);
+    variant_type y22(x22);
+
+    boost::hash<variant_type> hasher;
+
+    BOOST_TEST(hasher(y11) != hasher(y21));
+    BOOST_TEST(hasher(y11) != hasher(y22));
+    BOOST_TEST(hasher(y12) != hasher(y21));
+    BOOST_TEST(hasher(y12) != hasher(y22));
+}
+
+#endif
+
+int main()
+{
+#if BOOST_HASH_HAS_VARIANT
+    test_variant_int();
+    test_variant_unique_types();
+#else
+    BOOST_LIGHTWEIGHT_TEST_OSTREAM << "<variant> not available." << std::endl;
+#endif
+    return boost::report_errors();
+}

From 27b2732916ba73178ce58ab8fa5e0c9600b327fe Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Sun, 21 Jan 2018 21:09:50 +0000
Subject: [PATCH 11/20] Make hash_value(monostate) inline

---
 include/boost/container_hash/hash/hash.hpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/boost/container_hash/hash/hash.hpp b/include/boost/container_hash/hash/hash.hpp
index 4b10870..1165977 100644
--- a/include/boost/container_hash/hash/hash.hpp
+++ b/include/boost/container_hash/hash/hash.hpp
@@ -517,7 +517,7 @@ namespace boost
 #endif
 
 #if BOOST_HASH_HAS_VARIANT
-    std::size_t hash_value(std::monostate) {
+    inline std::size_t hash_value(std::monostate) {
         return 0x87654321;
     }
 

From cb6a0246dfa8de20f938dcd3320df54e83d1b059 Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Sun, 21 Jan 2018 21:09:50 +0000
Subject: [PATCH 12/20] Test members in compile_test, rather than inheritance

Inheritance from unary_function is deprecated in recent C++. Better to
check the member types. Could probably drop test altogether.
---
 test/compile_time.hpp | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/test/compile_time.hpp b/test/compile_time.hpp
index db6bc59..d7631b8 100644
--- a/test/compile_time.hpp
+++ b/test/compile_time.hpp
@@ -5,14 +5,16 @@
 
 #include <boost/config.hpp>
 #include <boost/static_assert.hpp>
-#include <boost/type_traits/is_base_and_derived.hpp>
+#include <boost/type_traits/is_same.hpp>
 
 template <class T>
 void compile_time_tests(T*)
 {
-#if !defined(_HAS_AUTO_PTR_ETC) || _HAS_AUTO_PTR_ETC
-    BOOST_STATIC_ASSERT((boost::is_base_and_derived<
-        std::unary_function<T, std::size_t>, BOOST_HASH_TEST_NAMESPACE::hash<T> >::value));
-#endif
+    BOOST_STATIC_ASSERT((boost::is_same<T,
+        typename BOOST_HASH_TEST_NAMESPACE::hash<T>::argument_type
+    >::value));
+    BOOST_STATIC_ASSERT((boost::is_same<std::size_t,
+        typename BOOST_HASH_TEST_NAMESPACE::hash<T>::result_type
+    >::value));
 }
 

From 0ad83592af44d8bd793500f7570de83c7825a96f Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Sun, 21 Jan 2018 21:09:50 +0000
Subject: [PATCH 13/20] Test g++-7, and display output from hash_info

---
 .travis.yml | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/.travis.yml b/.travis.yml
index 21f9e8f..644cb20 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -14,6 +14,16 @@ matrix:
         env: |
             USER_CONFIG="using gcc : : g++-4.8 -Werror ;"
             CXXSTD=03,11
+      - compiler: g++-7
+        env: |
+            USER_CONFIG="using gcc : : g++-7 -Werror ;"
+            CXXSTD=11,14,17
+        addons:
+          apt:
+            packages:
+              - g++-7
+            sources:
+              - ubuntu-toolchain-r-test
       - compiler: clang
         env: |
             USER_CONFIG="using clang : : clang++ -Werror ;"
@@ -64,4 +74,5 @@ before_script:
 
 script:
     - cd ${TRAVIS_BUILD_DIR}/test
+    - ${HOME}/opt/bin/b2 --verbose-test -j 3 cxxstd=$CXXSTD -q ${BJAM_TOOLSET} include=${BOOST_ROOT} include=${TRAVIS_BUILD_DIR}/include hash_info
     - ${HOME}/opt/bin/b2 -j 3 cxxstd=$CXXSTD -q ${BJAM_TOOLSET} include=${BOOST_ROOT} include=${TRAVIS_BUILD_DIR}/include

From 8963c38770484d87574eee5a6cc46f1c926275b0 Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Mon, 22 Jan 2018 11:56:43 +0000
Subject: [PATCH 14/20] Fix hash_info for older Visual C++

---
 test/hash_info.cpp | 11 ++++-------
 1 file changed, 4 insertions(+), 7 deletions(-)

diff --git a/test/hash_info.cpp b/test/hash_info.cpp
index 7159d1f..db63df9 100644
--- a/test/hash_info.cpp
+++ b/test/hash_info.cpp
@@ -15,11 +15,8 @@ struct msvc_version {
     std::size_t version;
     char const* description;
 
-    bool operator<(std::size_t v) const {
-        return version < v;
-    }
-    friend bool operator<(std::size_t v1, msvc_version const& v2) {
-        return v1 < v2.version;
+    friend bool operator<(msvc_version const& v1, msvc_version const& v2) {
+        return v1.version < v2.version;
     }
 };
 
@@ -45,11 +42,11 @@ void write_compiler_info() {
         {1912, "Visual C++ 14.12, VS2017 15.5"}
     };
 
-    std::size_t msvc = BOOST_MSVC;
+    msvc_version msvc = { BOOST_MSVC, "" };
     msvc_version* v = std::upper_bound(versions,
         versions + sizeof(versions) / sizeof(*versions),
         msvc) - 1;
-    std::size_t difference = BOOST_MSVC - v->version;
+    std::size_t difference = msvc.version - v->version;
 
     std::cout << v->description << std::endl;
     if (difference) {

From 17809c3cbc5cf1e5287574baa69108de74af11f0 Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Mon, 22 Jan 2018 12:18:05 +0000
Subject: [PATCH 15/20] Add appveyor tests

---
 .appveyor.yml | 33 +++++++++++++++++++++++++++++++++
 1 file changed, 33 insertions(+)
 create mode 100644 .appveyor.yml

diff --git a/.appveyor.yml b/.appveyor.yml
new file mode 100644
index 0000000..76189c2
--- /dev/null
+++ b/.appveyor.yml
@@ -0,0 +1,33 @@
+# Copyright 2017 Daniel James
+# Distributed under the Boost Software License, Version 1.0.
+# (See accompanying file LICENSE_1_0.txt or copy at http://boost.org/LICENSE_1_0.txt)
+
+version: 1.0.{build}-{branch}
+
+shallow_clone: true
+
+environment:
+  matrix:
+    - APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2013
+      TOOLSET: msvc-10.0,msvc-11.0,msvc-12.0
+    - APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2015
+      TOOLSET: msvc-14.0
+    - APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2017
+      TOOLSET: msvc-14.1
+
+install:
+  - cd c:\projects
+  - curl -sSL -o boost.7z https://dl.bintray.com/boostorg/release/1.66.0/source/boost_1_66_0.7z
+  - 7z x boost.7z
+  - set BOOST_ROOT=c:\projects\boost_1_66_0
+  - rd /s /q %BOOST_ROOT%\boost\functional\hash
+  - cd %BOOST_ROOT%\tools\build
+  - cmd /c bootstrap
+  - cd %APPVEYOR_BUILD_FOLDER%
+  - echo. 2>Jamroot.jam
+
+build: off
+
+test_script:
+  - cd %APPVEYOR_BUILD_FOLDER%\test
+  - cmd /c %BOOST_ROOT%\tools\build\b2 -j 3 toolset=%TOOLSET% include=%APPVEYOR_BUILD_FOLDER%\include include=%BOOST_ROOT%

From e01239286c87c5d14635be4b0e39cd6f4f7b7323 Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Wed, 24 Jan 2018 12:56:14 +0000
Subject: [PATCH 16/20] Avoid conversion warning

---
 test/hash_variant_test.cpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/hash_variant_test.cpp b/test/hash_variant_test.cpp
index 80f317a..31520f4 100644
--- a/test/hash_variant_test.cpp
+++ b/test/hash_variant_test.cpp
@@ -48,12 +48,12 @@ void test_variant_int()
 
 struct custom1 {
     int value;
-    friend std::size_t hash_value(custom1 v) { return v.value; }
+    friend std::size_t hash_value(custom1 v) { return boost::hash_value(v.value); }
 };
 
 struct custom2 {
     int value;
-    friend std::size_t hash_value(custom2 v) { return v.value; }
+    friend std::size_t hash_value(custom2 v) { return boost::hash_value(v.value); }
 };
 
 void test_variant_unique_types()

From 8ea85f5ad21e486206e6e4223013fd6753ed41aa Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Wed, 24 Jan 2018 13:29:52 +0000
Subject: [PATCH 17/20] Use error codes that are hopefully present on mingw

---
 test/hash_system_error_test.cpp | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/test/hash_system_error_test.cpp b/test/hash_system_error_test.cpp
index 71eb714..14228d1 100644
--- a/test/hash_system_error_test.cpp
+++ b/test/hash_system_error_test.cpp
@@ -17,9 +17,9 @@
 
 void test_error_code()
 {
-    std::error_code err1a = std::make_error_code(std::errc::address_family_not_supported);
-    std::error_code err1b = std::make_error_code(std::errc::address_family_not_supported);
-    std::error_code err2 = std::make_error_code(std::errc::address_in_use);
+    std::error_code err1a = std::make_error_code(std::errc::argument_list_too_long);
+    std::error_code err1b = std::make_error_code(std::errc::argument_list_too_long);
+    std::error_code err2 = std::make_error_code(std::errc::bad_file_descriptor);
 
     boost::hash<std::error_code> hasher;
 
@@ -30,9 +30,9 @@ void test_error_code()
 
 void test_error_condition()
 {
-    std::error_condition err1a = std::make_error_condition(std::errc::address_family_not_supported);
-    std::error_condition err1b = std::make_error_condition(std::errc::address_family_not_supported);
-    std::error_condition err2 = std::make_error_condition(std::errc::address_in_use);
+    std::error_condition err1a = std::make_error_condition(std::errc::directory_not_empty);
+    std::error_condition err1b = std::make_error_condition(std::errc::directory_not_empty);
+    std::error_condition err2 = std::make_error_condition(std::errc::filename_too_long);
 
     boost::hash<std::error_condition> hasher;
 

From 1e263669cbb3989379eb460b89742f7e5e2a56d6 Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Wed, 24 Jan 2018 13:37:35 +0000
Subject: [PATCH 18/20] Use `unsigned` for version number in hash_info.cpp

Was getting a `size_t` to `unsigned int` conversion when writing to stream, so
just use `unsigned` from the start.
---
 test/hash_info.cpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/hash_info.cpp b/test/hash_info.cpp
index db63df9..34378f5 100644
--- a/test/hash_info.cpp
+++ b/test/hash_info.cpp
@@ -12,7 +12,7 @@
 #if defined(BOOST_MSVC)
 
 struct msvc_version {
-    std::size_t version;
+    unsigned version;
     char const* description;
 
     friend bool operator<(msvc_version const& v1, msvc_version const& v2) {
@@ -46,7 +46,7 @@ void write_compiler_info() {
     msvc_version* v = std::upper_bound(versions,
         versions + sizeof(versions) / sizeof(*versions),
         msvc) - 1;
-    std::size_t difference = msvc.version - v->version;
+    unsigned difference = msvc.version - v->version;
 
     std::cout << v->description << std::endl;
     if (difference) {

From d45e3986f3d8706ee19da7a8b3283cd3a9af1983 Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Sat, 27 Jan 2018 11:47:09 +0000
Subject: [PATCH 19/20] Remove forwarding headers in container_hash

---
 include/boost/container_hash/hash.hpp     |  7 -------
 include/boost/container_hash/hash_fwd.hpp | 11 -----------
 2 files changed, 18 deletions(-)
 delete mode 100644 include/boost/container_hash/hash.hpp
 delete mode 100644 include/boost/container_hash/hash_fwd.hpp

diff --git a/include/boost/container_hash/hash.hpp b/include/boost/container_hash/hash.hpp
deleted file mode 100644
index 4a06833..0000000
--- a/include/boost/container_hash/hash.hpp
+++ /dev/null
@@ -1,7 +0,0 @@
-
-// Copyright 2005-2009 Daniel James.
-// 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)
-
-#include <boost/container_hash/hash/hash.hpp>
-
diff --git a/include/boost/container_hash/hash_fwd.hpp b/include/boost/container_hash/hash_fwd.hpp
deleted file mode 100644
index 5ff4801..0000000
--- a/include/boost/container_hash/hash_fwd.hpp
+++ /dev/null
@@ -1,11 +0,0 @@
-
-// Copyright 2005-2009 Daniel James.
-// 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)
-
-#include <boost/config.hpp>
-#if defined(BOOST_HAS_PRAGMA_ONCE)
-#pragma once
-#endif
-
-#include <boost/container_hash/hash/hash_fwd.hpp>

From d20a68efdb13df9461321047766798ffa265e194 Mon Sep 17 00:00:00 2001
From: Daniel James <daniel@calamity.org.uk>
Date: Sat, 27 Jan 2018 11:48:59 +0000
Subject: [PATCH 20/20] Move headers into top level of container_hash directory

---
 .../container_hash/{hash => }/detail/float_functions.hpp    | 0
 .../boost/container_hash/{hash => }/detail/hash_float.hpp   | 4 ++--
 include/boost/container_hash/{hash => }/detail/limits.hpp   | 0
 include/boost/container_hash/{hash => }/extensions.hpp      | 2 +-
 include/boost/container_hash/{hash => }/hash.hpp            | 6 +++---
 include/boost/container_hash/{hash => }/hash_fwd.hpp        | 0
 include/boost/functional/hash.hpp                           | 2 +-
 include/boost/functional/hash/extensions.hpp                | 2 +-
 include/boost/functional/hash/hash.hpp                      | 2 +-
 include/boost/functional/hash/hash_fwd.hpp                  | 2 +-
 include/boost/functional/hash_fwd.hpp                       | 2 +-
 test/extensions_hpp_test.cpp                                | 6 +++---
 test/hash_float_test.hpp                                    | 4 ++--
 test/hash_number_test.cpp                                   | 2 +-
 14 files changed, 17 insertions(+), 17 deletions(-)
 rename include/boost/container_hash/{hash => }/detail/float_functions.hpp (100%)
 rename include/boost/container_hash/{hash => }/detail/hash_float.hpp (98%)
 rename include/boost/container_hash/{hash => }/detail/limits.hpp (100%)
 rename include/boost/container_hash/{hash => }/extensions.hpp (99%)
 rename include/boost/container_hash/{hash => }/hash.hpp (99%)
 rename include/boost/container_hash/{hash => }/hash_fwd.hpp (100%)

diff --git a/include/boost/container_hash/hash/detail/float_functions.hpp b/include/boost/container_hash/detail/float_functions.hpp
similarity index 100%
rename from include/boost/container_hash/hash/detail/float_functions.hpp
rename to include/boost/container_hash/detail/float_functions.hpp
diff --git a/include/boost/container_hash/hash/detail/hash_float.hpp b/include/boost/container_hash/detail/hash_float.hpp
similarity index 98%
rename from include/boost/container_hash/hash/detail/hash_float.hpp
rename to include/boost/container_hash/detail/hash_float.hpp
index d0f7f55..f763428 100644
--- a/include/boost/container_hash/hash/detail/hash_float.hpp
+++ b/include/boost/container_hash/detail/hash_float.hpp
@@ -11,8 +11,8 @@
 #pragma once
 #endif
 
-#include <boost/container_hash/hash/detail/float_functions.hpp>
-#include <boost/container_hash/hash/detail/limits.hpp>
+#include <boost/container_hash/detail/float_functions.hpp>
+#include <boost/container_hash/detail/limits.hpp>
 #include <boost/core/enable_if.hpp>
 #include <boost/integer/static_log2.hpp>
 #include <boost/cstdint.hpp>
diff --git a/include/boost/container_hash/hash/detail/limits.hpp b/include/boost/container_hash/detail/limits.hpp
similarity index 100%
rename from include/boost/container_hash/hash/detail/limits.hpp
rename to include/boost/container_hash/detail/limits.hpp
diff --git a/include/boost/container_hash/hash/extensions.hpp b/include/boost/container_hash/extensions.hpp
similarity index 99%
rename from include/boost/container_hash/hash/extensions.hpp
rename to include/boost/container_hash/extensions.hpp
index d8e34db..393b702 100644
--- a/include/boost/container_hash/hash/extensions.hpp
+++ b/include/boost/container_hash/extensions.hpp
@@ -18,7 +18,7 @@
 #pragma once
 #endif
 
-#include <boost/container_hash/hash/hash.hpp>
+#include <boost/container_hash/hash.hpp>
 #include <boost/detail/container_fwd.hpp>
 #include <boost/core/enable_if.hpp>
 #include <boost/static_assert.hpp>
diff --git a/include/boost/container_hash/hash/hash.hpp b/include/boost/container_hash/hash.hpp
similarity index 99%
rename from include/boost/container_hash/hash/hash.hpp
rename to include/boost/container_hash/hash.hpp
index 1165977..76de793 100644
--- a/include/boost/container_hash/hash/hash.hpp
+++ b/include/boost/container_hash/hash.hpp
@@ -16,9 +16,9 @@
 #if !defined(BOOST_FUNCTIONAL_HASH_HASH_HPP)
 #define BOOST_FUNCTIONAL_HASH_HASH_HPP
 
-#include <boost/container_hash/hash/hash_fwd.hpp>
+#include <boost/container_hash/hash_fwd.hpp>
 #include <functional>
-#include <boost/container_hash/hash/detail/hash_float.hpp>
+#include <boost/container_hash/detail/hash_float.hpp>
 #include <string>
 #include <boost/limits.hpp>
 #include <boost/type_traits/is_enum.hpp>
@@ -757,5 +757,5 @@ namespace boost
 
 #if !defined(BOOST_HASH_NO_EXTENSIONS) \
     && !defined(BOOST_FUNCTIONAL_HASH_EXTENSIONS_HPP)
-#include <boost/container_hash/hash/extensions.hpp>
+#include <boost/container_hash/extensions.hpp>
 #endif
diff --git a/include/boost/container_hash/hash/hash_fwd.hpp b/include/boost/container_hash/hash_fwd.hpp
similarity index 100%
rename from include/boost/container_hash/hash/hash_fwd.hpp
rename to include/boost/container_hash/hash_fwd.hpp
diff --git a/include/boost/functional/hash.hpp b/include/boost/functional/hash.hpp
index 6122b35..327a3ec 100644
--- a/include/boost/functional/hash.hpp
+++ b/include/boost/functional/hash.hpp
@@ -3,4 +3,4 @@
 // 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)
 
-#include <boost/container_hash/hash/hash.hpp>
+#include <boost/container_hash/hash.hpp>
diff --git a/include/boost/functional/hash/extensions.hpp b/include/boost/functional/hash/extensions.hpp
index bd436fb..ab14211 100644
--- a/include/boost/functional/hash/extensions.hpp
+++ b/include/boost/functional/hash/extensions.hpp
@@ -3,4 +3,4 @@
 // 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)
 
-#include <boost/container_hash/hash/extensions.hpp>
+#include <boost/container_hash/extensions.hpp>
diff --git a/include/boost/functional/hash/hash.hpp b/include/boost/functional/hash/hash.hpp
index 6122b35..327a3ec 100644
--- a/include/boost/functional/hash/hash.hpp
+++ b/include/boost/functional/hash/hash.hpp
@@ -3,4 +3,4 @@
 // 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)
 
-#include <boost/container_hash/hash/hash.hpp>
+#include <boost/container_hash/hash.hpp>
diff --git a/include/boost/functional/hash/hash_fwd.hpp b/include/boost/functional/hash/hash_fwd.hpp
index aeffad0..62bc23c 100644
--- a/include/boost/functional/hash/hash_fwd.hpp
+++ b/include/boost/functional/hash/hash_fwd.hpp
@@ -3,4 +3,4 @@
 // 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)
 
-#include <boost/container_hash/hash/hash_fwd.hpp>
+#include <boost/container_hash/hash_fwd.hpp>
diff --git a/include/boost/functional/hash_fwd.hpp b/include/boost/functional/hash_fwd.hpp
index aeffad0..62bc23c 100644
--- a/include/boost/functional/hash_fwd.hpp
+++ b/include/boost/functional/hash_fwd.hpp
@@ -3,4 +3,4 @@
 // 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)
 
-#include <boost/container_hash/hash/hash_fwd.hpp>
+#include <boost/container_hash/hash_fwd.hpp>
diff --git a/test/extensions_hpp_test.cpp b/test/extensions_hpp_test.cpp
index 54d1054..a388c23 100644
--- a/test/extensions_hpp_test.cpp
+++ b/test/extensions_hpp_test.cpp
@@ -3,14 +3,14 @@
 // 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)
 
-// Check that boost/container_hash/hash/extensions.hpp works okay.
+// Check that boost/container_hash/extensions.hpp works okay.
 //
-// It probably should be in boost/container_hash/hash/detail, but since it isn't it
+// It probably should be in boost/container_hash/detail, but since it isn't it
 // should work.
 
 #include "./config.hpp"
 
-#include <boost/container_hash/hash/extensions.hpp>
+#include <boost/container_hash/extensions.hpp>
 
 int main() {
     int x[2] = { 2, 3 };
diff --git a/test/hash_float_test.hpp b/test/hash_float_test.hpp
index a73c31f..ab79a12 100644
--- a/test/hash_float_test.hpp
+++ b/test/hash_float_test.hpp
@@ -14,8 +14,8 @@
 #include <boost/core/lightweight_test.hpp>
 
 #include <cmath>
-#include <boost/container_hash/hash/detail/limits.hpp>
-#include <boost/container_hash/hash/detail/float_functions.hpp>
+#include <boost/container_hash/detail/limits.hpp>
+#include <boost/container_hash/detail/float_functions.hpp>
 #include <boost/config/workaround.hpp>
 
 #include <iostream>
diff --git a/test/hash_number_test.cpp b/test/hash_number_test.cpp
index c78783e..72ab626 100644
--- a/test/hash_number_test.cpp
+++ b/test/hash_number_test.cpp
@@ -14,7 +14,7 @@
 #include <iostream>
 #include <boost/core/lightweight_test.hpp>
 
-#include <boost/container_hash/hash/detail/limits.hpp>
+#include <boost/container_hash/detail/limits.hpp>
 #include <boost/core/enable_if.hpp>
 
 #include "./compile_time.hpp"