Make typedef private and rename it so older versions of msvc don't erroneously treat the typedef like it's in scope when doing template instantiation

This reverts commit 9bc471310e.

.appveyor.yml

@@ -40,52 +40,16 @@ environment:
       APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2015
       B2_TOOLSET: msvc-12.0,msvc-14.0
 
-    - FLAVOR: Visual Studio 2017 C++14/17
+    - FLAVOR: Visual Studio 2017
       APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2017
       B2_CXXSTD: 14,17
       B2_TOOLSET: msvc-14.1
 
-    - FLAVOR: Visual Studio 2017 C++2a Strict
+    - FLAVOR: Visual Studio 2017
       APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2017
-      B2_CXXFLAGS: -permissive-
-      B2_CXXSTD: 2a
+      B2_CXXSTD: latest
       B2_TOOLSET: msvc-14.1
 
-    - FLAVOR: Visual Studio 2019
-      APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2019
-      B2_CXXFLAGS: -permissive-
-      B2_CXXSTD: 14,17
-      B2_TOOLSET: msvc-14.2
-
-    - FLAVOR: Visual Studio 2022
-      APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2022
-      B2_CXXFLAGS: -permissive-
-      B2_CXXSTD: 14,17
-      B2_TOOLSET: msvc-14.3
-
-    # C++20 Jobs split out from above due to build timeout
-    - FLAVOR: Visual Studio 2019 C++2a
-      APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2019
-      B2_CXXFLAGS: -permissive-
-      B2_CXXSTD: 2a
-      B2_TOOLSET: msvc-14.2
-
-    - FLAVOR: Visual Studio 2022 C++20
-      APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2022
-      B2_CXXFLAGS: -permissive-
-      B2_CXXSTD: 20
-      B2_TOOLSET: msvc-14.3
-
-    - FLAVOR: clang-cl C++11, C++14
-      APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2019
-      B2_CXXSTD: 11,14
-      B2_TOOLSET: clang-win
-    # Extra job as compilation takes to long
-    - FLAVOR: clang-cl C++17, C++latest
-      APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2019
-      B2_CXXSTD: 17,latest
-      B2_TOOLSET: clang-win
-
     - FLAVOR: cygwin (32-bit)
       APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2017
       ADDPATH: C:\cygwin\bin;
@@ -100,30 +64,65 @@ environment:
       B2_CXXSTD: 03,11,14,1z
       B2_TOOLSET: gcc
 
-    # (Currently) the images up to 2017 use an older Cygwin
-    # This tests that the library works with more recent versions
     - FLAVOR: cygwin (64-bit, latest)
       APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2022
       ADDPATH: C:\cygwin64\bin;
       B2_ADDRESS_MODEL: 64
-      B2_CXXSTD: 03,11,14,1z
+      B2_CXXSTD: 03
       B2_TOOLSET: gcc
-      MAYFAIL: true
+      B2_FLAGS: "include=libs/unordered/test/unordered include=libs/unordered/test/exception"
 
-    - FLAVOR: mingw32
-      APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2015
+    - FLAVOR: cygwin (64-bit, latest)
+      APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2022
+      ADDPATH: C:\cygwin64\bin;
+      B2_ADDRESS_MODEL: 64
+      B2_CXXSTD: 11
+      B2_TOOLSET: gcc
+      B2_FLAGS: "include=libs/unordered/test/unordered include=libs/unordered/test/exception"
+
+    - FLAVOR: cygwin (64-bit, latest)
+      APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2022
+      ADDPATH: C:\cygwin64\bin;
+      B2_ADDRESS_MODEL: 64
+      B2_CXXSTD: 14
+      B2_TOOLSET: gcc
+      B2_FLAGS: "include=libs/unordered/test/unordered include=libs/unordered/test/exception"
+
+    - FLAVOR: cygwin (64-bit, latest)
+      APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2022
+      ADDPATH: C:\cygwin64\bin;
+      B2_ADDRESS_MODEL: 64
+      B2_CXXSTD: 1z
+      B2_TOOLSET: gcc
+      B2_FLAGS: "include=libs/unordered/test/unordered include=libs/unordered/test/exception"
+
+    - FLAVOR: mingw-w64, 32 bit
+      APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2019
+      ADDPATH: C:\mingw-w64\i686-8.1.0-posix-dwarf-rt_v6-rev0\mingw32\bin;
+      B2_CXXSTD: 03,11,14
+      B2_TOOLSET: gcc
       B2_ADDRESS_MODEL: 32
-      ADDPATH: C:\mingw\bin;
-      B2_CXXSTD: 03,11,14,1z
-      B2_TOOLSET: gcc
-      MAYFAIL: true
 
-    - FLAVOR: mingw64
+    - FLAVOR: mingw-w64, 32 bit
+      APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2019
+      ADDPATH: C:\mingw-w64\i686-8.1.0-posix-dwarf-rt_v6-rev0\mingw32\bin;
+      B2_CXXSTD: 17,2a
+      B2_TOOLSET: gcc
+      B2_ADDRESS_MODEL: 32
+
+    - FLAVOR: mingw-w64, 64 bit
       APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2019
       ADDPATH: C:\mingw-w64\x86_64-8.1.0-posix-seh-rt_v6-rev0\mingw64\bin;
-      B2_ADDRESS_MODEL: 64
-      B2_CXXSTD: 03,11,14,17,2a
+      B2_CXXSTD: 03,11,14
       B2_TOOLSET: gcc
+      B2_ADDRESS_MODEL: 64
+
+    - FLAVOR: mingw-w64, 64 bit
+      APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2019
+      ADDPATH: C:\mingw-w64\x86_64-8.1.0-posix-seh-rt_v6-rev0\mingw64\bin;
+      B2_CXXSTD: 17,2a
+      B2_TOOLSET: gcc
+      B2_ADDRESS_MODEL: 64
 
     #- FLAVOR: CodeCov (VS 2019)
     #  APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2019

.drone.jsonnet

@@ -0,0 +1,388 @@
+# Copyright 2022 Peter Dimov
+# Distributed under the Boost Software License, Version 1.0.
+# https://www.boost.org/LICENSE_1_0.txt
+
+local library = "unordered";
+
+local triggers =
+{
+    branch: [ "master", "develop", "feature/*", "bugfix/*" ]
+};
+
+local ubsan = { UBSAN: '1', UBSAN_OPTIONS: 'print_stacktrace=1' };
+local asan = { ASAN: '1' };
+
+local linux_pipeline(name, image, environment, packages = "", sources = [], arch = "amd64") =
+{
+    name: name,
+    kind: "pipeline",
+    type: "docker",
+    trigger: triggers,
+    platform:
+    {
+        os: "linux",
+        arch: arch
+    },
+    steps:
+    [
+        {
+            name: "everything",
+            image: image,
+            environment: environment,
+            commands:
+            [
+                'set -e',
+                'uname -a',
+                'wget -O - https://apt.llvm.org/llvm-snapshot.gpg.key | apt-key add -',
+            ] +
+            (if sources != [] then [ ('apt-add-repository "' + source + '"') for source in sources ] else []) +
+            (if packages != "" then [ 'apt-get update', 'apt-get -y install ' + packages ] else []) +
+            [
+                'export LIBRARY=' + library,
+                './.drone/drone.sh',
+            ]
+        }
+    ]
+};
+
+local macos_pipeline(name, environment, xcode_version = "12.2", osx_version = "catalina", arch = "amd64") =
+{
+    name: name,
+    kind: "pipeline",
+    type: "exec",
+    trigger: triggers,
+    platform: {
+        "os": "darwin",
+        "arch": arch
+    },
+    node: {
+        "os": osx_version
+    },
+    steps: [
+        {
+            name: "everything",
+            environment: environment + { "DEVELOPER_DIR": "/Applications/Xcode-" + xcode_version + ".app/Contents/Developer" },
+            commands:
+            [
+                'uname -a',
+                'export LIBRARY=' + library,
+                './.drone/drone.sh',
+            ]
+        }
+    ]
+};
+
+local windows_pipeline(name, image, environment, arch = "amd64") =
+{
+    name: name,
+    kind: "pipeline",
+    type: "docker",
+    trigger: triggers,
+    platform:
+    {
+        os: "windows",
+        arch: arch
+    },
+    "steps":
+    [
+        {
+            name: "everything",
+            image: image,
+            environment: environment,
+            commands:
+            [
+                'echo $env:DRONE_STAGE_MACHINE',
+                'cmd /C .drone\\\\drone.bat ' + library,
+            ]
+        }
+    ]
+};
+
+[
+    linux_pipeline(
+        "Linux 14.04 GCC 4.4 32/64",
+        "cppalliance/droneubuntu1404:1",
+        { TOOLSET: 'gcc', COMPILER: 'g++-4.4', CXXSTD: '98,0x', ADDRMD: '32,64' },
+        "g++-4.4-multilib",
+        [ "ppa:ubuntu-toolchain-r/test" ],
+    ),
+
+    linux_pipeline(
+        "Linux 14.04 GCC 4.6 32/64",
+        "cppalliance/droneubuntu1404:1",
+        { TOOLSET: 'gcc', COMPILER: 'g++-4.6', CXXSTD: '98,0x', ADDRMD: '32,64' },
+        "g++-4.6-multilib",
+        [ "ppa:ubuntu-toolchain-r/test" ],
+    ),
+
+    linux_pipeline(
+        "Linux 14.04 GCC 4.7 32/64",
+        "cppalliance/droneubuntu1404:1",
+        { TOOLSET: 'gcc', COMPILER: 'g++-4.7', CXXSTD: '98,0x', ADDRMD: '32,64' },
+        "g++-4.7-multilib",
+        [ "ppa:ubuntu-toolchain-r/test" ],
+    ),
+
+    linux_pipeline(
+        "Linux 14.04 GCC 4.8* 32/64",
+        "cppalliance/droneubuntu1404:1",
+        { TOOLSET: 'gcc', COMPILER: 'g++', CXXSTD: '03,11', ADDRMD: '32,64' },
+    ),
+
+    linux_pipeline(
+        "Linux 14.04 GCC 4.9 32/64",
+        "cppalliance/droneubuntu1404:1",
+        { TOOLSET: 'gcc', COMPILER: 'g++-4.9', CXXSTD: '03,11', ADDRMD: '32,64' },
+        "g++-4.9-multilib",
+        [ "ppa:ubuntu-toolchain-r/test" ],
+    ),
+
+    linux_pipeline(
+        "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",
+        "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 (03,11,14)",
+        "cppalliance/droneubuntu2204:1",
+        { TOOLSET: 'gcc', COMPILER: 'g++-12', CXXSTD: '03,11,14', ADDRMD: '32' } + asan,
+        "g++-12-multilib",
+    ),
+
+    linux_pipeline(
+        "Linux 22.04 GCC 12 32 ASAN (17,20,2b)",
+        "cppalliance/droneubuntu2204:1",
+        { TOOLSET: 'gcc', COMPILER: 'g++-12', CXXSTD: '17,20,2b', ADDRMD: '32' } + asan,
+        "g++-12-multilib",
+    ),
+
+    linux_pipeline(
+        "Linux 22.04 GCC 12 64 ASAN (03,11,14)",
+        "cppalliance/droneubuntu2204:1",
+        { TOOLSET: 'gcc', COMPILER: 'g++-12', CXXSTD: '03,11,14', ADDRMD: '64' } + asan,
+        "g++-12-multilib",
+    ),
+
+    linux_pipeline(
+        "Linux 22.04 GCC 12 64 ASAN (17,20,2b)",
+        "cppalliance/droneubuntu2204:1",
+        { TOOLSET: 'gcc', COMPILER: 'g++-12', CXXSTD: '17,20,2b', ADDRMD: '64' } + asan,
+        "g++-12-multilib",
+    ),
+
+    linux_pipeline(
+        "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++-13', CXXSTD: '03,11,14,17,20' },
+        "clang-13",
+    ),
+
+    linux_pipeline(
+        "Linux 22.04 Clang 14 UBSAN",
+        "cppalliance/droneubuntu2204:1",
+        { TOOLSET: 'clang', COMPILER: 'clang++-14', CXXSTD: '03,11,14,17,20' } + ubsan,
+        "clang-14",
+    ),
+
+    linux_pipeline(
+        "Linux 22.04 Clang 14 ASAN",
+        "cppalliance/droneubuntu2204:1",
+        { TOOLSET: 'clang', COMPILER: 'clang++-14', CXXSTD: '03,11,14,17,20' } + asan,
+        "clang-14",
+    ),
+
+    linux_pipeline(
+        "Linux 22.04 Clang 15",
+        "cppalliance/droneubuntu2204:1",
+        { TOOLSET: 'clang', COMPILER: 'clang++-15', CXXSTD: '03,11,14,17,20,2b' },
+        "clang-15",
+        ["deb http://apt.llvm.org/jammy/ llvm-toolchain-jammy-15 main"],
+    ),
+
+    macos_pipeline(
+        "MacOS 10.15 Xcode 12.2 UBSAN",
+        { TOOLSET: 'clang', COMPILER: 'clang++', CXXSTD: '03,11,14,1z' } + ubsan,
+    ),
+
+    macos_pipeline(
+        "MacOS 12.4 Xcode 13.4.1 ASAN",
+        { TOOLSET: 'clang', COMPILER: 'clang++', CXXSTD: '03,11,14,1z' } + 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(
+        "Windows VS2017 msvc-14.1",
+        "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.bat

@@ -0,0 +1,23 @@
+@REM Copyright 2022 Peter Dimov
+@REM Distributed under the Boost Software License, Version 1.0.
+@REM https://www.boost.org/LICENSE_1_0.txt
+
+@ECHO ON
+
+set LIBRARY=%1
+set DRONE_BUILD_DIR=%CD%
+
+set BOOST_BRANCH=develop
+if "%DRONE_BRANCH%" == "master" set BOOST_BRANCH=master
+cd ..
+git clone -b %BOOST_BRANCH% --depth 1 https://github.com/boostorg/boost.git boost-root
+cd boost-root
+git submodule update --init tools/boostdep
+xcopy /s /e /q %DRONE_BUILD_DIR% libs\%LIBRARY%\
+python tools/boostdep/depinst/depinst.py %LIBRARY%
+cmd /c bootstrap
+b2 -d0 headers
+
+if not "%CXXSTD%" == "" set CXXSTD=cxxstd=%CXXSTD%
+if not "%ADDRMD%" == "" set ADDRMD=address-model=%ADDRMD%
+b2 -j3 libs/%LIBRARY%/test toolset=%TOOLSET% %CXXSTD% %ADDRMD% variant=debug,release embed-manifest-via=linker

.drone/drone.sh

@@ -0,0 +1,25 @@
+#!/bin/bash
+
+# Copyright 2022 Peter Dimov
+# Distributed under the Boost Software License, Version 1.0.
+# https://www.boost.org/LICENSE_1_0.txt
+
+set -ex
+export PATH=~/.local/bin:/usr/local/bin:$PATH
+
+DRONE_BUILD_DIR=$(pwd)
+
+BOOST_BRANCH=develop
+if [ "$DRONE_BRANCH" = "master" ]; then BOOST_BRANCH=master; fi
+
+cd ..
+git clone -b $BOOST_BRANCH --depth 1 https://github.com/boostorg/boost.git boost-root
+cd boost-root
+git submodule update --init tools/boostdep
+cp -r $DRONE_BUILD_DIR/* libs/$LIBRARY
+python tools/boostdep/depinst/depinst.py $LIBRARY
+./bootstrap.sh
+./b2 -d0 headers
+
+echo "using $TOOLSET : : $COMPILER ;" > ~/user-config.jam
+./b2 -j3 libs/$LIBRARY/test toolset=$TOOLSET cxxstd=$CXXSTD variant=debug,release ${ADDRMD:+address-model=$ADDRMD} ${UBSAN:+undefined-sanitizer=norecover debug-symbols=on} ${ASAN:+address-sanitizer=norecover debug-symbols=on} ${LINKFLAGS:+linkflags=$LINKFLAGS}

.github/workflows/ci.yml

@@ -42,46 +42,38 @@ jobs:
       matrix:
         include:
           # Linux, gcc
-          - { compiler: gcc-4.8,   cxxstd: '03,11',          os: ubuntu-18.04 }
-          - { compiler: gcc-4.9,   cxxstd: '03,11',          os: ubuntu-20.04, container: 'ubuntu:16.04' }
-          - { compiler: gcc-5,     cxxstd: '03,11,14,1z',    os: ubuntu-18.04 }
-          - { compiler: gcc-6,     cxxstd: '03,11,14,17',    os: ubuntu-18.04 }
-          - { compiler: gcc-7,     cxxstd: '03,11,14,17',    os: ubuntu-18.04 }
-          - { compiler: gcc-8,     cxxstd: '03,11,14,17,2a', os: ubuntu-18.04 }
-          - { compiler: gcc-9,     cxxstd: '03,11,14,17,2a', os: ubuntu-18.04 }
-          - { compiler: gcc-10,    cxxstd: '03,11,14,17,20', os: ubuntu-20.04 }
-          - { compiler: gcc-11,    cxxstd: '03,11,14,17,20', os: ubuntu-20.04 }
-          - { compiler: gcc-12,    cxxstd: '03,11,14,17,20', os: ubuntu-22.04 }
-          - { name: GCC w/ sanitizers, sanitize: yes,
-              compiler: gcc-12,    cxxstd: '03,11,14,17,20', os: ubuntu-22.04 }
+          - { compiler: gcc-7,     cxxstd: '03,11,14,17',    os: ubuntu-20.04, install: 'g++-7' }
+          - { compiler: gcc-8,     cxxstd: '03,11,14,17',    os: ubuntu-20.04, install: 'g++-8' }
+          - { compiler: gcc-9,     cxxstd: '03,11,14,17',    os: ubuntu-20.04, install: 'g++-9' }
+          - { compiler: gcc-10,    cxxstd: '03,11,14,17,20', os: ubuntu-22.04, install: 'g++-10' }
+          - { compiler: gcc-11,    cxxstd: '03,11,14,17,20', os: ubuntu-22.04, install: 'g++-11' }
+          - { name: "gcc-12 w/ sanitizers (03,11,14)", sanitize: yes,
+              compiler: gcc-12,    cxxstd: '03,11,14',       os: ubuntu-22.04, ccache_key: "san1" }
+          - { name: "gcc-12 w/ sanitizers (17,20,2b)", sanitize: yes,
+              compiler: gcc-12,    cxxstd: '17,20,2b',       os: ubuntu-22.04, ccache_key: "san2" }
           - { name: Collect coverage, coverage: yes,
-              compiler: gcc-8,     cxxstd: '03,11',          os: ubuntu-20.04, install: 'g++-8-multilib', address-model: '32,64' }
+              compiler: gcc-8,     cxxstd: '03,11',          os: ubuntu-20.04, install: 'g++-8-multilib', address-model: '32,64', ccache_key: "cov" }
 
-          # Linux, clang
-          - { compiler: clang-3.7, cxxstd: '03,11,14',       os: ubuntu-20.04, container: 'ubuntu:16.04' }
-          - { compiler: clang-3.8, cxxstd: '03,11,14',       os: ubuntu-20.04, container: 'ubuntu:16.04' }
-          - { compiler: clang-3.9, cxxstd: '03,11,14',       os: ubuntu-18.04 }
-          - { compiler: clang-4.0, cxxstd: '03,11,14',       os: ubuntu-18.04 }
-          - { compiler: clang-5.0, cxxstd: '03,11,14,1z',    os: ubuntu-18.04 }
-          - { compiler: clang-6.0, cxxstd: '03,11,14,17',    os: ubuntu-18.04 }
-          - { compiler: clang-7,   cxxstd: '03,11,14,17',    os: ubuntu-18.04 }
-          # Note: clang-8 does not fully support C++20, so it is not compatible with some libstdc++ versions in this mode
-          - { compiler: clang-8,   cxxstd: '03,11,14,17,2a', os: ubuntu-18.04, install: 'clang-8 g++-7', gcc_toolchain: 7 }
-          - { compiler: clang-9,   cxxstd: '03,11,14,17,2a', os: ubuntu-20.04 }
-          - { compiler: clang-10,  cxxstd: '03,11,14,17,20', os: ubuntu-20.04 }
-          - { compiler: clang-11,  cxxstd: '03,11,14,17,20', os: ubuntu-20.04 }
-          - { compiler: clang-12,  cxxstd: '03,11,14,17,20', os: ubuntu-20.04 }
-          - { compiler: clang-13,  cxxstd: '03,11,14,17,20', os: ubuntu-22.04 }
-          - { compiler: clang-14,  cxxstd: '03,11,14,17,20', os: ubuntu-22.04 }
-
-          # libc++
-          - { compiler: clang-6.0, cxxstd: '03,11,14',       os: ubuntu-18.04, stdlib: libc++, install: 'clang-6.0 libc++-dev libc++abi-dev' }
-          - { compiler: clang-12,  cxxstd: '03,11,14,17,20', os: ubuntu-20.04, stdlib: libc++, install: 'clang-12 libc++-12-dev libc++abi-12-dev' }
-          - { name: Clang w/ sanitizers, sanitize: yes,
-              compiler: clang-12,  cxxstd: '03,11,14,17,20', os: ubuntu-20.04, stdlib: libc++, install: 'clang-12 libc++-12-dev libc++abi-12-dev' }
+          # Linux, clang, libc++
+          - { compiler: clang-7,   cxxstd: '03,11,14,17',       os: ubuntu-20.04, stdlib: libc++, install: 'clang-7 libc++-7-dev libc++abi-7-dev' }
+          - { compiler: clang-10,  cxxstd: '03,11,14,17,20',    os: ubuntu-20.04, stdlib: libc++, install: 'clang-10 libc++-10-dev libc++abi-10-dev' }
+          - { compiler: clang-11,  cxxstd: '03,11,14,17,20',    os: ubuntu-22.04, stdlib: libc++, install: 'clang-11 libc++-11-dev libc++abi-11-dev' }
+          # clang-12 doesn't work on ubuntu-22.04, the linker can't find -lunwind for some reason
+          - { name: "clang-12 w/ sanitizers (03,11,14)", sanitize: yes,
+              compiler: clang-12,  cxxstd: '03,11,14',          os: ubuntu-20.04, stdlib: libc++, install: 'clang-12 libc++-12-dev libc++abi-12-dev', ccache_key: "san1" }
+          - { name: "clang-12 w/ sanitizers (17,20,2b)", sanitize: yes,
+              compiler: clang-12,  cxxstd: '17,20,2b',          os: ubuntu-20.04, stdlib: libc++, install: 'clang-12 libc++-12-dev libc++abi-12-dev', ccache_key: "san2" }
+          - { compiler: clang-13,  cxxstd: '03,11,14,17,20,2b', os: ubuntu-22.04, stdlib: libc++, install: 'clang-13 libc++-13-dev libc++abi-13-dev' }
+          - { compiler: clang-14,  cxxstd: '03,11,14,17,20,2b', os: ubuntu-22.04, stdlib: libc++, install: 'clang-14 libc++-14-dev libc++abi-14-dev' }
+          # not using libc++ because of https://github.com/llvm/llvm-project/issues/52771
+          - { name: "clang-14 w/ sanitizers (03,11,14)", sanitize: yes,
+              compiler: clang-14,  cxxstd: '03,11,14',          os: ubuntu-22.04, ccache_key: "san1" }
+          - { name: "clang-14 w/ sanitizers (17,20,2b)", sanitize: yes,
+              compiler: clang-14,  cxxstd: '17,20,2b',          os: ubuntu-22.04, ccache_key: "san2" }
 
           # OSX, clang
-          - { compiler: clang,     cxxstd: '03,11,14,17,2a', os: macos-10.15, sanitize: yes }
+          - { compiler: clang,     cxxstd: '03,11,14,17,2a',    os: macos-11, }
+          - { compiler: clang,     cxxstd: '03,11,14,17,2a',    os: macos-12, sanitize: yes }
 
     timeout-minutes: 120
     runs-on: ${{matrix.os}}
@@ -120,8 +112,8 @@ jobs:
         if: env.B2_USE_CCACHE
         with:
           path: ~/.ccache
-          key: ${{matrix.os}}-${{matrix.container}}-${{matrix.compiler}}-${{github.sha}}
-          restore-keys: ${{matrix.os}}-${{matrix.container}}-${{matrix.compiler}}-
+          key: ${{matrix.os}}-${{matrix.container}}-${{matrix.compiler}}-${{matrix.ccache_key}}-${{github.sha}}
+          restore-keys: ${{matrix.os}}-${{matrix.container}}-${{matrix.compiler}}-${{matrix.ccache_key}}-
 
       - name: Fetch Boost.CI
         uses: actions/checkout@v3
@@ -226,11 +218,13 @@ jobs:
       fail-fast: false
       matrix:
         include:
-          - { toolset: msvc-14.0, cxxstd: '14,latest',      addrmd: '32,64', os: windows-2019 }
-          - { toolset: msvc-14.2, cxxstd: '14,17,20',       addrmd: '32,64', os: windows-2019 }
-          - { toolset: msvc-14.3, cxxstd: '14,17,20,latest',addrmd: '32,64', os: windows-2022 }
-          - { toolset: clang-win, cxxstd: '14,17,latest',   addrmd: '32,64', os: windows-2022 }
-          - { toolset: gcc,       cxxstd: '03,11,14,17,2a', addrmd: '64',    os: windows-2019 }
+          - { toolset: msvc-14.0, cxxstd: '14,latest',       addrmd: '32,64', os: windows-2019, variant: 'debug,release' }
+          - { toolset: msvc-14.2, cxxstd: '14,17,20,latest', addrmd: '32,64', os: windows-2019, variant: 'debug,release' }
+          - { toolset: msvc-14.3, cxxstd: '14,17,20,latest', addrmd: '32,64', os: windows-2022, variant: 'debug,release' }
+          - { toolset: msvc-14.3, cxxstd: '14',              addrmd: '64',    os: windows-2022, variant: 'debug', defines: '_ALLOW_RTCc_IN_STL', cxxflags: '/RTCc'              }
+          - { toolset: msvc-14.3, cxxstd: '14',              addrmd: '32',    os: windows-2022, variant: 'debug', defines: '_ALLOW_RTCc_IN_STL', cxxflags: '"/RTCc /arch:IA32"' }
+          - { toolset: clang-win, cxxstd: '14,17,latest',    addrmd: '32,64', os: windows-2022, variant: 'debug,release' }
+          - { toolset: gcc,       cxxstd: '03,11,14,17,2a',  addrmd: '64',    os: windows-2019, variant: 'debug,release' }
 
     runs-on: ${{matrix.os}}
 
@@ -259,6 +253,9 @@ jobs:
           B2_TOOLSET: ${{matrix.toolset}}
           B2_CXXSTD: ${{matrix.cxxstd}}
           B2_ADDRESS_MODEL: ${{matrix.addrmd}}
+          B2_DEFINES: ${{matrix.defines}}
+          B2_VARIANT: ${{matrix.variant}}
+          B2_CXXFLAGS: ${{matrix.cxxflags}}
 
       - name: Collect coverage
         shell: powershell

.gitignore

@@ -1 +1,2 @@
 /doc/html/
+/doc/pdf/

CMakeLists.txt

@@ -18,7 +18,6 @@ target_link_libraries(boost_unordered
     Boost::config
     Boost::container_hash
     Boost::core
-    Boost::iterator
     Boost::move
     Boost::mp11
     Boost::predef

benchmark/.gitignore

@@ -0,0 +1,3 @@
+enwik8
+enwik9
+*.exe

benchmark/string.cpp

@@ -3,17 +3,19 @@
 // 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_map.hpp>
-#include <boost/multi_index_container.hpp>
-#include <boost/multi_index/hashed_index.hpp>
-#include <boost/multi_index/member.hpp>
+#include <boost/unordered/unordered_flat_map.hpp>
 #include <boost/core/detail/splitmix64.hpp>
 #include <boost/config.hpp>
 #ifdef HAVE_ABSEIL
 # include "absl/container/node_hash_map.h"
 # include "absl/container/flat_hash_map.h"
 #endif
+#ifdef HAVE_ANKERL_UNORDERED_DENSE
+# include "ankerl/unordered_dense.h"
+#endif
 #include <unordered_map>
 #include <vector>
 #include <memory>
@@ -137,7 +139,14 @@ template<class Map> BOOST_NOINLINE void test_iteration( Map& map, std::chrono::s
     {
         if( it->second & 1 )
         {
-            map.erase( it++ );
+            if constexpr( std::is_void_v< decltype( map.erase( it ) ) > )
+            {
+                map.erase( it++ );
+            }
+            else
+            {
+                it = map.erase( it );
+            }
         }
         else
         {
@@ -159,13 +168,9 @@ template<class Map> BOOST_NOINLINE void test_erase( Map& map, std::chrono::stead
 
     print_time( t1, "Consecutive erase",  0, map.size() );
 
+    for( unsigned i = 1; i <= N; ++i )
     {
-        boost::detail::splitmix64 rng;
-
-        for( unsigned i = 1; i <= N; ++i )
-        {
-            map.erase( indices2[ i ] );
-        }
+        map.erase( indices2[ i ] );
     }
 
     print_time( t1, "Random erase",  0, map.size() );
@@ -257,24 +262,6 @@ template<template<class...> class Map> BOOST_NOINLINE void test( char const* lab
     times.push_back( rec );
 }
 
-// multi_index emulation of unordered_map
-
-template<class K, class V> struct pair
-{
-    K first;
-    mutable V second;
-};
-
-using namespace boost::multi_index;
-
-template<class K, class V> using multi_index_map = multi_index_container<
-  pair<K, V>,
-  indexed_by<
-    hashed_unique< member<pair<K, V>, K, &pair<K, V>::first> >
-  >,
-  ::allocator< pair<K, V> >
->;
-
 // aliases using the counting allocator
 
 template<class K, class V> using allocator_for = ::allocator< std::pair<K const, V> >;
@@ -285,6 +272,9 @@ template<class K, class V> using std_unordered_map =
 template<class K, class V> using boost_unordered_map =
     boost::unordered_map<K, V, boost::hash<K>, std::equal_to<K>, allocator_for<K, V>>;
 
+template<class K, class V> using boost_unordered_flat_map =
+    boost::unordered_flat_map<K, V, boost::hash<K>, std::equal_to<K>, allocator_for<K, V>>;
+
 #ifdef HAVE_ABSEIL
 
 template<class K, class V> using absl_node_hash_map =
@@ -295,6 +285,13 @@ template<class K, class V> using absl_flat_hash_map =
 
 #endif
 
+#ifdef HAVE_ANKERL_UNORDERED_DENSE
+
+template<class K, class V> using ankerl_unordered_dense_map =
+    ankerl::unordered_dense::map<K, V, ankerl::unordered_dense::hash<K>, std::equal_to<K>, ::allocator< std::pair<K, V> >>;
+
+#endif
+
 // fnv1a_hash
 
 template<int Bits> struct fnv1a_hash_impl;
@@ -337,7 +334,10 @@ template<> struct fnv1a_hash_impl<64>
     }
 };
 
-struct fnv1a_hash: fnv1a_hash_impl< std::numeric_limits<std::size_t>::digits > {};
+struct fnv1a_hash: fnv1a_hash_impl< std::numeric_limits<std::size_t>::digits >
+{
+    using is_avalanching = void;
+};
 
 template<class K, class V> using std_unordered_map_fnv1a =
 std::unordered_map<K, V, fnv1a_hash, std::equal_to<K>, allocator_for<K, V>>;
@@ -345,13 +345,8 @@ std::unordered_map<K, V, fnv1a_hash, std::equal_to<K>, allocator_for<K, V>>;
 template<class K, class V> using boost_unordered_map_fnv1a =
     boost::unordered_map<K, V, fnv1a_hash, std::equal_to<K>, allocator_for<K, V>>;
 
-template<class K, class V> using multi_index_map_fnv1a = multi_index_container<
-  pair<K, V>,
-  indexed_by<
-    hashed_unique< member<pair<K, V>, K, &pair<K, V>::first>, fnv1a_hash >
-  >,
-  ::allocator< pair<K, V> >
->;
+template<class K, class V> using boost_unordered_flat_map_fnv1a =
+    boost::unordered_flat_map<K, V, fnv1a_hash, std::equal_to<K>, allocator_for<K, V>>;
 
 #ifdef HAVE_ABSEIL
 
@@ -363,30 +358,45 @@ template<class K, class V> using absl_flat_hash_map_fnv1a =
 
 #endif
 
+#ifdef HAVE_ANKERL_UNORDERED_DENSE
+
+template<class K, class V> using ankerl_unordered_dense_map_fnv1a =
+    ankerl::unordered_dense::map<K, V, fnv1a_hash, std::equal_to<K>, ::allocator< std::pair<K, V> >>;
+
+#endif
+
 //
 
 int main()
 {
     init_indices();
 
-#if 0
-
     test<std_unordered_map>( "std::unordered_map" );
     test<boost_unordered_map>( "boost::unordered_map" );
-    test<multi_index_map>( "multi_index_map" );
+    test<boost_unordered_flat_map>( "boost::unordered_flat_map" );
+
+#ifdef HAVE_ANKERL_UNORDERED_DENSE
+
+    test<ankerl_unordered_dense_map>( "ankerl::unordered_dense::map" );
+
+#endif
 
 #ifdef HAVE_ABSEIL
 
     test<absl_node_hash_map>( "absl::node_hash_map" );
     test<absl_flat_hash_map>( "absl::flat_hash_map" );
 
-#endif
-
 #endif
 
     test<std_unordered_map_fnv1a>( "std::unordered_map, FNV-1a" );
     test<boost_unordered_map_fnv1a>( "boost::unordered_map, FNV-1a" );
-    test<multi_index_map_fnv1a>( "multi_index_map, FNV-1a" );
+    test<boost_unordered_flat_map_fnv1a>( "boost::unordered_flat_map, FNV-1a" );
+
+#ifdef HAVE_ANKERL_UNORDERED_DENSE
+
+    test<ankerl_unordered_dense_map_fnv1a>( "ankerl::unordered_dense::map, FNV-1a" );
+
+#endif
 
 #ifdef HAVE_ABSEIL
 
@@ -399,7 +409,7 @@ int main()
 
     for( auto const& x: times )
     {
-        std::cout << std::setw( 30 ) << ( x.label_ + ": " ) << std::setw( 5 ) << x.time_ << " ms, " << std::setw( 9 ) << x.bytes_ << " bytes in " << x.count_ << " allocations\n";
+        std::cout << std::setw( 38 ) << ( x.label_ + ": " ) << std::setw( 5 ) << x.time_ << " ms, " << std::setw( 9 ) << x.bytes_ << " bytes in " << x.count_ << " allocations\n";
     }
 }
 

benchmark/string_view.cpp

@@ -3,17 +3,19 @@
 // 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_map.hpp>
-#include <boost/multi_index_container.hpp>
-#include <boost/multi_index/hashed_index.hpp>
-#include <boost/multi_index/member.hpp>
+#include <boost/unordered/unordered_flat_map.hpp>
 #include <boost/core/detail/splitmix64.hpp>
 #include <boost/config.hpp>
 #ifdef HAVE_ABSEIL
 # include "absl/container/node_hash_map.h"
 # include "absl/container/flat_hash_map.h"
 #endif
+#ifdef HAVE_ANKERL_UNORDERED_DENSE
+# include "ankerl/unordered_dense.h"
+#endif
 #include <unordered_map>
 #include <string_view>
 #include <vector>
@@ -138,7 +140,14 @@ template<class Map> BOOST_NOINLINE void test_iteration( Map& map, std::chrono::s
     {
         if( it->second & 1 )
         {
-            map.erase( it++ );
+            if constexpr( std::is_void_v< decltype( map.erase( it ) ) > )
+            {
+                map.erase( it++ );
+            }
+            else
+            {
+                it = map.erase( it );
+            }
         }
         else
         {
@@ -160,13 +169,9 @@ template<class Map> BOOST_NOINLINE void test_erase( Map& map, std::chrono::stead
 
     print_time( t1, "Consecutive erase",  0, map.size() );
 
+    for( unsigned i = 1; i <= N; ++i )
     {
-        boost::detail::splitmix64 rng;
-
-        for( unsigned i = 1; i <= N; ++i )
-        {
-            map.erase( indices2[ i ] );
-        }
+        map.erase( indices2[ i ] );
     }
 
     print_time( t1, "Random erase",  0, map.size() );
@@ -258,24 +263,6 @@ template<template<class...> class Map> BOOST_NOINLINE void test( char const* lab
     times.push_back( rec );
 }
 
-// multi_index emulation of unordered_map
-
-template<class K, class V> struct pair
-{
-    K first;
-    mutable V second;
-};
-
-using namespace boost::multi_index;
-
-template<class K, class V> using multi_index_map = multi_index_container<
-  pair<K, V>,
-  indexed_by<
-    hashed_unique< member<pair<K, V>, K, &pair<K, V>::first> >
-  >,
-  ::allocator< pair<K, V> >
->;
-
 // aliases using the counting allocator
 
 template<class K, class V> using allocator_for = ::allocator< std::pair<K const, V> >;
@@ -286,6 +273,9 @@ template<class K, class V> using std_unordered_map =
 template<class K, class V> using boost_unordered_map =
     boost::unordered_map<K, V, boost::hash<K>, std::equal_to<K>, allocator_for<K, V>>;
 
+template<class K, class V> using boost_unordered_flat_map =
+    boost::unordered_flat_map<K, V, boost::hash<K>, std::equal_to<K>, allocator_for<K, V>>;
+
 #ifdef HAVE_ABSEIL
 
 template<class K, class V> using absl_node_hash_map =
@@ -296,6 +286,13 @@ template<class K, class V> using absl_flat_hash_map =
 
 #endif
 
+#ifdef HAVE_ANKERL_UNORDERED_DENSE
+
+template<class K, class V> using ankerl_unordered_dense_map =
+    ankerl::unordered_dense::map<K, V, ankerl::unordered_dense::hash<K>, std::equal_to<K>, ::allocator< std::pair<K, V> >>;
+
+#endif
+
 // fnv1a_hash
 
 template<int Bits> struct fnv1a_hash_impl;
@@ -338,7 +335,10 @@ template<> struct fnv1a_hash_impl<64>
     }
 };
 
-struct fnv1a_hash: fnv1a_hash_impl< std::numeric_limits<std::size_t>::digits > {};
+struct fnv1a_hash: fnv1a_hash_impl< std::numeric_limits<std::size_t>::digits >
+{
+    using is_avalanching = void;
+};
 
 template<class K, class V> using std_unordered_map_fnv1a =
 std::unordered_map<K, V, fnv1a_hash, std::equal_to<K>, allocator_for<K, V>>;
@@ -346,13 +346,8 @@ std::unordered_map<K, V, fnv1a_hash, std::equal_to<K>, allocator_for<K, V>>;
 template<class K, class V> using boost_unordered_map_fnv1a =
     boost::unordered_map<K, V, fnv1a_hash, std::equal_to<K>, allocator_for<K, V>>;
 
-template<class K, class V> using multi_index_map_fnv1a = multi_index_container<
-  pair<K, V>,
-  indexed_by<
-    hashed_unique< member<pair<K, V>, K, &pair<K, V>::first>, fnv1a_hash >
-  >,
-  ::allocator< pair<K, V> >
->;
+template<class K, class V> using boost_unordered_flat_map_fnv1a =
+    boost::unordered_flat_map<K, V, fnv1a_hash, std::equal_to<K>, allocator_for<K, V>>;
 
 #ifdef HAVE_ABSEIL
 
@@ -364,30 +359,45 @@ template<class K, class V> using absl_flat_hash_map_fnv1a =
 
 #endif
 
+#ifdef HAVE_ANKERL_UNORDERED_DENSE
+
+template<class K, class V> using ankerl_unordered_dense_map_fnv1a =
+    ankerl::unordered_dense::map<K, V, fnv1a_hash, std::equal_to<K>, ::allocator< std::pair<K, V> >>;
+
+#endif
+
 //
 
 int main()
 {
     init_indices();
 
-#if 0
-
     test<std_unordered_map>( "std::unordered_map" );
     test<boost_unordered_map>( "boost::unordered_map" );
-    test<multi_index_map>( "multi_index_map" );
+    test<boost_unordered_flat_map>( "boost::unordered_flat_map" );
+
+#ifdef HAVE_ANKERL_UNORDERED_DENSE
+
+    test<ankerl_unordered_dense_map>( "ankerl::unordered_dense::map" );
+
+#endif
 
 #ifdef HAVE_ABSEIL
 
     test<absl_node_hash_map>( "absl::node_hash_map" );
     test<absl_flat_hash_map>( "absl::flat_hash_map" );
 
-#endif
-
 #endif
 
     test<std_unordered_map_fnv1a>( "std::unordered_map, FNV-1a" );
     test<boost_unordered_map_fnv1a>( "boost::unordered_map, FNV-1a" );
-    test<multi_index_map_fnv1a>( "multi_index_map, FNV-1a" );
+    test<boost_unordered_flat_map_fnv1a>( "boost::unordered_flat_map, FNV-1a" );
+
+#ifdef HAVE_ANKERL_UNORDERED_DENSE
+
+    test<ankerl_unordered_dense_map_fnv1a>( "ankerl::unordered_dense::map, FNV-1a" );
+
+#endif
 
 #ifdef HAVE_ABSEIL
 
@@ -400,7 +410,7 @@ int main()
 
     for( auto const& x: times )
     {
-        std::cout << std::setw( 30 ) << ( x.label_ + ": " ) << std::setw( 5 ) << x.time_ << " ms, " << std::setw( 9 ) << x.bytes_ << " bytes in " << x.count_ << " allocations\n";
+        std::cout << std::setw( 38 ) << ( x.label_ + ": " ) << std::setw( 5 ) << x.time_ << " ms, " << std::setw( 9 ) << x.bytes_ << " bytes in " << x.count_ << " allocations\n";
     }
 }
 

benchmark/uint32.cpp

@@ -3,17 +3,20 @@
 // 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_map.hpp>
-#include <boost/multi_index_container.hpp>
-#include <boost/multi_index/hashed_index.hpp>
-#include <boost/multi_index/member.hpp>
+#include <boost/unordered/unordered_flat_map.hpp>
+#include <boost/endian/conversion.hpp>
 #include <boost/core/detail/splitmix64.hpp>
 #include <boost/config.hpp>
 #ifdef HAVE_ABSEIL
 # include "absl/container/node_hash_map.h"
 # include "absl/container/flat_hash_map.h"
 #endif
+#ifdef HAVE_ANKERL_UNORDERED_DENSE
+# include "ankerl/unordered_dense.h"
+#endif
 #include <unordered_map>
 #include <vector>
 #include <memory>
@@ -62,7 +65,7 @@ static void init_indices()
 
     for( unsigned i = 1; i <= N*2; ++i )
     {
-        indices3.push_back( (std::uint32_t)i << 11 );
+        indices3.push_back( boost::endian::endian_reverse( static_cast<std::uint32_t>( i ) ) );
     }
 }
 
@@ -87,7 +90,7 @@ template<class Map> BOOST_NOINLINE void test_insert( Map& map, std::chrono::stea
         map.insert( { indices3[ i ], i } );
     }
 
-    print_time( t1, "Consecutive shifted insert",  0, map.size() );
+    print_time( t1, "Consecutive reversed insert",  0, map.size() );
 
     std::cout << std::endl;
 }
@@ -133,7 +136,7 @@ template<class Map> BOOST_NOINLINE void test_lookup( Map& map, std::chrono::stea
         }
     }
 
-    print_time( t1, "Consecutive shifted lookup",  s, map.size() );
+    print_time( t1, "Consecutive reversed lookup",  s, map.size() );
 
     std::cout << std::endl;
 }
@@ -146,7 +149,14 @@ template<class Map> BOOST_NOINLINE void test_iteration( Map& map, std::chrono::s
     {
         if( it->second & 1 )
         {
-            map.erase( it++ );
+            if constexpr( std::is_void_v< decltype( map.erase( it ) ) > )
+            {
+                map.erase( it++ );
+            }
+            else
+            {
+                it = map.erase( it );
+            }
         }
         else
         {
@@ -168,13 +178,9 @@ template<class Map> BOOST_NOINLINE void test_erase( Map& map, std::chrono::stead
 
     print_time( t1, "Consecutive erase",  0, map.size() );
 
+    for( unsigned i = 1; i <= N; ++i )
     {
-        boost::detail::splitmix64 rng;
-
-        for( unsigned i = 1; i <= N; ++i )
-        {
-            map.erase( indices2[ i ] );
-        }
+        map.erase( indices2[ i ] );
     }
 
     print_time( t1, "Random erase",  0, map.size() );
@@ -184,7 +190,7 @@ template<class Map> BOOST_NOINLINE void test_erase( Map& map, std::chrono::stead
         map.erase( indices3[ i ] );
     }
 
-    print_time( t1, "Consecutive shifted erase",  0, map.size() );
+    print_time( t1, "Consecutive reversed erase",  0, map.size() );
 
     std::cout << std::endl;
 }
@@ -273,24 +279,6 @@ template<template<class...> class Map> BOOST_NOINLINE void test( char const* lab
     times.push_back( rec );
 }
 
-// multi_index emulation of unordered_map
-
-template<class K, class V> struct pair
-{
-    K first;
-    mutable V second;
-};
-
-using namespace boost::multi_index;
-
-template<class K, class V> using multi_index_map = multi_index_container<
-  pair<K, V>,
-  indexed_by<
-    hashed_unique< member<pair<K, V>, K, &pair<K, V>::first> >
-  >,
-  ::allocator< pair<K, V> >
->;
-
 // aliases using the counting allocator
 
 template<class K, class V> using allocator_for = ::allocator< std::pair<K const, V> >;
@@ -301,6 +289,9 @@ template<class K, class V> using std_unordered_map =
 template<class K, class V> using boost_unordered_map =
     boost::unordered_map<K, V, boost::hash<K>, std::equal_to<K>, allocator_for<K, V>>;
 
+template<class K, class V> using boost_unordered_flat_map =
+    boost::unordered_flat_map<K, V, boost::hash<K>, std::equal_to<K>, allocator_for<K, V>>;
+
 #ifdef HAVE_ABSEIL
 
 template<class K, class V> using absl_node_hash_map =
@@ -311,13 +302,26 @@ template<class K, class V> using absl_flat_hash_map =
 
 #endif
 
+#ifdef HAVE_ANKERL_UNORDERED_DENSE
+
+template<class K, class V> using ankerl_unordered_dense_map =
+    ankerl::unordered_dense::map<K, V, ankerl::unordered_dense::hash<K>, std::equal_to<K>, ::allocator< std::pair<K, V> >>;
+
+#endif
+
 int main()
 {
     init_indices();
 
     test<std_unordered_map>( "std::unordered_map" );
     test<boost_unordered_map>( "boost::unordered_map" );
-    test<multi_index_map>( "multi_index_map" );
+    test<boost_unordered_flat_map>( "boost::unordered_flat_map" );
+
+#ifdef HAVE_ANKERL_UNORDERED_DENSE
+
+    test<ankerl_unordered_dense_map>( "ankerl::unordered_dense::map" );
+
+#endif
 
 #ifdef HAVE_ABSEIL
 
@@ -330,7 +334,7 @@ int main()
 
     for( auto const& x: times )
     {
-        std::cout << std::setw( 25 ) << ( x.label_ + ": " ) << std::setw( 5 ) << x.time_ << " ms, " << std::setw( 9 ) << x.bytes_ << " bytes in " << x.count_ << " allocations\n";
+        std::cout << std::setw( 30 ) << ( x.label_ + ": " ) << std::setw( 5 ) << x.time_ << " ms, " << std::setw( 9 ) << x.bytes_ << " bytes in " << x.count_ << " allocations\n";
     }
 }
 

benchmark/uint64.cpp

@@ -3,17 +3,20 @@
 // 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_map.hpp>
-#include <boost/multi_index_container.hpp>
-#include <boost/multi_index/hashed_index.hpp>
-#include <boost/multi_index/member.hpp>
+#include <boost/unordered/unordered_flat_map.hpp>
+#include <boost/endian/conversion.hpp>
 #include <boost/core/detail/splitmix64.hpp>
 #include <boost/config.hpp>
 #ifdef HAVE_ABSEIL
 # include "absl/container/node_hash_map.h"
 # include "absl/container/flat_hash_map.h"
 #endif
+#ifdef HAVE_ANKERL_UNORDERED_DENSE
+# include "ankerl/unordered_dense.h"
+#endif
 #include <unordered_map>
 #include <vector>
 #include <memory>
@@ -62,7 +65,7 @@ static void init_indices()
 
     for( unsigned i = 1; i <= N*2; ++i )
     {
-        indices3.push_back( (std::uint64_t)i << 40 );
+        indices3.push_back( boost::endian::endian_reverse( static_cast<std::uint64_t>( i ) ) );
     }
 }
 
@@ -87,7 +90,7 @@ template<class Map> BOOST_NOINLINE void test_insert( Map& map, std::chrono::stea
         map.insert( { indices3[ i ], i } );
     }
 
-    print_time( t1, "Consecutive shifted insert",  0, map.size() );
+    print_time( t1, "Consecutive reversed insert",  0, map.size() );
 
     std::cout << std::endl;
 }
@@ -133,7 +136,7 @@ template<class Map> BOOST_NOINLINE void test_lookup( Map& map, std::chrono::stea
         }
     }
 
-    print_time( t1, "Consecutive shifted lookup",  s, map.size() );
+    print_time( t1, "Consecutive reversed lookup",  s, map.size() );
 
     std::cout << std::endl;
 }
@@ -146,7 +149,14 @@ template<class Map> BOOST_NOINLINE void test_iteration( Map& map, std::chrono::s
     {
         if( it->second & 1 )
         {
-            map.erase( it++ );
+            if constexpr( std::is_void_v< decltype( map.erase( it ) ) > )
+            {
+                map.erase( it++ );
+            }
+            else
+            {
+                it = map.erase( it );
+            }
         }
         else
         {
@@ -168,13 +178,9 @@ template<class Map> BOOST_NOINLINE void test_erase( Map& map, std::chrono::stead
 
     print_time( t1, "Consecutive erase",  0, map.size() );
 
+    for( unsigned i = 1; i <= N; ++i )
     {
-        boost::detail::splitmix64 rng;
-
-        for( unsigned i = 1; i <= N; ++i )
-        {
-            map.erase( indices2[ i ] );
-        }
+        map.erase( indices2[ i ] );
     }
 
     print_time( t1, "Random erase",  0, map.size() );
@@ -184,7 +190,7 @@ template<class Map> BOOST_NOINLINE void test_erase( Map& map, std::chrono::stead
         map.erase( indices3[ i ] );
     }
 
-    print_time( t1, "Consecutive shifted erase",  0, map.size() );
+    print_time( t1, "Consecutive reversed erase",  0, map.size() );
 
     std::cout << std::endl;
 }
@@ -273,24 +279,6 @@ template<template<class...> class Map> BOOST_NOINLINE void test( char const* lab
     times.push_back( rec );
 }
 
-// multi_index emulation of unordered_map
-
-template<class K, class V> struct pair
-{
-    K first;
-    mutable V second;
-};
-
-using namespace boost::multi_index;
-
-template<class K, class V> using multi_index_map = multi_index_container<
-  pair<K, V>,
-  indexed_by<
-    hashed_unique< member<pair<K, V>, K, &pair<K, V>::first> >
-  >,
-  ::allocator< pair<K, V> >
->;
-
 // aliases using the counting allocator
 
 template<class K, class V> using allocator_for = ::allocator< std::pair<K const, V> >;
@@ -301,6 +289,9 @@ template<class K, class V> using std_unordered_map =
 template<class K, class V> using boost_unordered_map =
     boost::unordered_map<K, V, boost::hash<K>, std::equal_to<K>, allocator_for<K, V>>;
 
+template<class K, class V> using boost_unordered_flat_map =
+    boost::unordered_flat_map<K, V, boost::hash<K>, std::equal_to<K>, allocator_for<K, V>>;
+
 #ifdef HAVE_ABSEIL
 
 template<class K, class V> using absl_node_hash_map =
@@ -311,13 +302,36 @@ template<class K, class V> using absl_flat_hash_map =
 
 #endif
 
+#ifdef HAVE_ANKERL_UNORDERED_DENSE
+
+template<class K, class V> using ankerl_unordered_dense_map =
+    ankerl::unordered_dense::map<K, V, ankerl::unordered_dense::hash<K>, std::equal_to<K>, ::allocator< std::pair<K, V> >>;
+
+#endif
+
 int main()
 {
     init_indices();
 
+#if defined(BOOST_LIBSTDCXX_VERSION) && __SIZE_WIDTH__ == 32
+
+    // Pathological behavior:
+    // https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104945
+
+#else
+
     test<std_unordered_map>( "std::unordered_map" );
+
+#endif
+
     test<boost_unordered_map>( "boost::unordered_map" );
-    test<multi_index_map>( "multi_index_map" );
+    test<boost_unordered_flat_map>( "boost::unordered_flat_map" );
+
+#ifdef HAVE_ANKERL_UNORDERED_DENSE
+
+    test<ankerl_unordered_dense_map>( "ankerl::unordered_dense::map" );
+
+#endif
 
 #ifdef HAVE_ABSEIL
 
@@ -330,7 +344,7 @@ int main()
 
     for( auto const& x: times )
     {
-        std::cout << std::setw( 25 ) << ( x.label_ + ": " ) << std::setw( 5 ) << x.time_ << " ms, " << std::setw( 9 ) << x.bytes_ << " bytes in " << x.count_ << " allocations\n";
+        std::cout << std::setw( 30 ) << ( x.label_ + ": " ) << std::setw( 5 ) << x.time_ << " ms, " << std::setw( 9 ) << x.bytes_ << " bytes in " << x.count_ << " allocations\n";
     }
 }
 

benchmark/uuid.cpp

@@ -0,0 +1,397 @@
+// Copyright 2021, 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_map.hpp>
+#include <boost/unordered/unordered_flat_map.hpp>
+#include <boost/endian/conversion.hpp>
+#include <boost/core/detail/splitmix64.hpp>
+#include <boost/container_hash/hash.hpp>
+#include <boost/config.hpp>
+#ifdef HAVE_ABSEIL
+# include "absl/container/node_hash_map.h"
+# include "absl/container/flat_hash_map.h"
+#endif
+#ifdef HAVE_ANKERL_UNORDERED_DENSE
+# include "ankerl/unordered_dense.h"
+#endif
+#include <unordered_map>
+#include <vector>
+#include <memory>
+#include <cstdint>
+#include <iostream>
+#include <iomanip>
+#include <chrono>
+#include <cstring>
+
+using namespace std::chrono_literals;
+
+static void print_time( std::chrono::steady_clock::time_point & t1, char const* label, std::uint64_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;
+
+struct uuid
+{
+    unsigned char data[ 16 ];
+
+    uuid(): data()
+    {
+    }
+
+    uuid( std::uint64_t low, std::uint64_t high ) noexcept
+    {
+        boost::endian::store_little_u64( data + 0, low );
+        boost::endian::store_little_u64( data + 8, high );
+    }
+
+    inline friend std::size_t hash_value( uuid const& u ) noexcept
+    {
+        std::uint64_t low  = boost::endian::load_little_u64( u.data + 0 );
+        std::uint64_t high = boost::endian::load_little_u64( u.data + 8 );
+
+        std::size_t r = 0;
+
+        boost::hash_combine( r, low );
+        boost::hash_combine( r, high );
+
+        return r;
+    }
+
+    inline friend bool operator==( uuid const& u1, uuid const& u2 ) noexcept
+    {
+        return std::memcmp( u1.data, u2.data, 16 ) == 0;
+    }
+};
+
+namespace std
+{
+
+template<> struct hash< ::uuid >
+{
+    std::size_t operator()( uuid const& u ) const noexcept
+    {
+        return hash_value( u );
+    }
+};
+
+} // namespace std
+
+static std::vector< uuid > indices1, indices2, indices3;
+
+static void init_indices()
+{
+    indices1.push_back( {} );
+
+    for( unsigned i = 1; i <= N*2; ++i )
+    {
+        indices1.push_back( { i, 0 } );
+    }
+
+    indices2.push_back( {} );
+
+    {
+        boost::detail::splitmix64 rng;
+
+        for( unsigned i = 1; i <= N*2; ++i )
+        {
+            indices2.push_back( { rng(), rng() } );
+        }
+    }
+
+    indices3.push_back( {} );
+
+    for( unsigned i = 1; i <= N*2; ++i )
+    {
+        uuid k( i, 0 );
+        std::reverse( k.data + 0, k.data + 16 );
+
+        indices3.push_back( k );
+    }
+}
+
+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() );
+
+    for( unsigned i = 1; i <= N; ++i )
+    {
+        map.insert( { indices3[ i ], i } );
+    }
+
+    print_time( t1, "Consecutive reversed 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::uint64_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() );
+
+    s = 0;
+
+    for( int j = 0; j < K; ++j )
+    {
+        for( unsigned i = 1; i <= N * 2; ++i )
+        {
+            auto it = map.find( indices3[ i ] );
+            if( it != map.end() ) s += it->second;
+        }
+    }
+
+    print_time( t1, "Consecutive reversed 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() );
+
+    for( unsigned i = 1; i <= N; ++i )
+    {
+        map.erase( indices3[ i ] );
+    }
+
+    print_time( t1, "Consecutive reversed erase",  0, map.size() );
+
+    std::cout << std::endl;
+}
+
+// counting allocator
+
+static std::size_t s_alloc_bytes = 0;
+static std::size_t s_alloc_count = 0;
+
+template<class T> struct allocator
+{
+    using value_type = T;
+
+    allocator() = default;
+
+    template<class U> allocator( allocator<U> const & ) noexcept
+    {
+    }
+
+    template<class U> bool operator==( allocator<U> const & ) const noexcept
+    {
+        return true;
+    }
+
+    template<class U> bool operator!=( allocator<U> const& ) const noexcept
+    {
+        return false;
+    }
+
+    T* allocate( std::size_t n ) const
+    {
+        s_alloc_bytes += n * sizeof(T);
+        s_alloc_count++;
+
+        return std::allocator<T>().allocate( n );
+    }
+
+    void deallocate( T* p, std::size_t n ) const noexcept
+    {
+        s_alloc_bytes -= n * sizeof(T);
+        s_alloc_count--;
+
+        std::allocator<T>().deallocate( p, n );
+    }
+};
+
+//
+
+struct record
+{
+    std::string label_;
+    long long time_;
+    std::size_t bytes_;
+    std::size_t count_;
+};
+
+static std::vector<record> times;
+
+template<template<class...> class Map> BOOST_NOINLINE void test( char const* label )
+{
+    std::cout << label << ":\n\n";
+
+    s_alloc_bytes = 0;
+    s_alloc_count = 0;
+
+    Map<uuid, std::uint64_t> map;
+
+    auto t0 = std::chrono::steady_clock::now();
+    auto t1 = t0;
+
+    test_insert( map, t1 );
+
+    std::cout << "Memory: " << s_alloc_bytes << " bytes in " << s_alloc_count << " allocations\n\n";
+
+    record rec = { label, 0, s_alloc_bytes, s_alloc_count };
+
+    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 );
+}
+
+// aliases using the counting allocator
+
+template<class K, class V> using allocator_for = ::allocator< std::pair<K const, V> >;
+
+template<class K, class V> using std_unordered_map =
+    std::unordered_map<K, V, std::hash<K>, std::equal_to<K>, allocator_for<K, V>>;
+
+template<class K, class V> using boost_unordered_map =
+    boost::unordered_map<K, V, boost::hash<K>, std::equal_to<K>, allocator_for<K, V>>;
+
+template<class K, class V> using boost_unordered_flat_map =
+    boost::unordered_flat_map<K, V, boost::hash<K>, std::equal_to<K>, allocator_for<K, V>>;
+
+#ifdef HAVE_ABSEIL
+
+template<class K, class V> using absl_node_hash_map =
+    absl::node_hash_map<K, V, absl::container_internal::hash_default_hash<K>, absl::container_internal::hash_default_eq<K>, allocator_for<K, V>>;
+
+template<class K, class V> using absl_flat_hash_map =
+    absl::flat_hash_map<K, V, absl::container_internal::hash_default_hash<K>, absl::container_internal::hash_default_eq<K>, allocator_for<K, V>>;
+
+#endif
+
+#ifdef HAVE_ANKERL_UNORDERED_DENSE
+
+template<class K, class V> using ankerl_unordered_dense_map =
+    ankerl::unordered_dense::map<K, V, ankerl::unordered_dense::hash<K>, std::equal_to<K>, ::allocator< std::pair<K, V> >>;
+
+#endif
+
+int main()
+{
+    init_indices();
+
+    test<std_unordered_map>( "std::unordered_map" );
+    test<boost_unordered_map>( "boost::unordered_map" );
+    test<boost_unordered_flat_map>( "boost::unordered_flat_map" );
+
+#ifdef HAVE_ANKERL_UNORDERED_DENSE
+
+    test<ankerl_unordered_dense_map>( "ankerl::unordered_dense::map" );
+
+#endif
+
+#ifdef HAVE_ABSEIL
+
+    test<absl_node_hash_map>( "absl::node_hash_map" );
+    test<absl_flat_hash_map>( "absl::flat_hash_map" );
+
+#endif
+
+    std::cout << "---\n\n";
+
+    for( auto const& x: times )
+    {
+        std::cout << std::setw( 30 ) << ( x.label_ + ": " ) << std::setw( 5 ) << x.time_ << " ms, " << std::setw( 9 ) << x.bytes_ << " bytes in " << x.count_ << " allocations\n";
+    }
+}
+
+#ifdef HAVE_ABSEIL
+# include "absl/container/internal/raw_hash_set.cc"
+# 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 +1,376 @@
+// Copyright 2021, 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_map.hpp>
+#include <boost/unordered/unordered_flat_map.hpp>
+#include <boost/regex.hpp>
+#ifdef HAVE_ABSEIL
+# include "absl/container/node_hash_map.h"
+# include "absl/container/flat_hash_map.h"
+#endif
+#ifdef HAVE_ANKERL_UNORDERED_DENSE
+# include "ankerl/unordered_dense.h"
+#endif
+#include <unordered_map>
+#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::size_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;
+}
+
+template<class Map> BOOST_NOINLINE void test_iteration( Map& map, std::chrono::steady_clock::time_point & t1 )
+{
+    std::size_t max = 0;
+    std::string_view word;
+
+    for( auto const& x: map )
+    {
+        if( x.second > max )
+        {
+            word = x.first;
+            max = x.second;
+        }
+    }
+
+    print_time( t1, "Iterate and find max element",  max, map.size() );
+
+    std::cout << std::endl;
+}
+
+// counting allocator
+
+static std::size_t s_alloc_bytes = 0;
+static std::size_t s_alloc_count = 0;
+
+template<class T> struct allocator
+{
+    using value_type = T;
+
+    allocator() = default;
+
+    template<class U> allocator( allocator<U> const & ) noexcept
+    {
+    }
+
+    template<class U> bool operator==( allocator<U> const & ) const noexcept
+    {
+        return true;
+    }
+
+    template<class U> bool operator!=( allocator<U> const& ) const noexcept
+    {
+        return false;
+    }
+
+    T* allocate( std::size_t n ) const
+    {
+        s_alloc_bytes += n * sizeof(T);
+        s_alloc_count++;
+
+        return std::allocator<T>().allocate( n );
+    }
+
+    void deallocate( T* p, std::size_t n ) const noexcept
+    {
+        s_alloc_bytes -= n * sizeof(T);
+        s_alloc_count--;
+
+        std::allocator<T>().deallocate( p, n );
+    }
+};
+
+//
+
+struct record
+{
+    std::string label_;
+    long long time_;
+    std::size_t bytes_;
+    std::size_t count_;
+};
+
+static std::vector<record> times;
+
+template<template<class...> class Map> BOOST_NOINLINE void test( char const* label )
+{
+    std::cout << label << ":\n\n";
+
+    s_alloc_bytes = 0;
+    s_alloc_count = 0;
+
+    Map<std::string_view, std::size_t> map;
+
+    auto t0 = std::chrono::steady_clock::now();
+    auto t1 = t0;
+
+    test_word_count( map, t1 );
+
+    std::cout << "Memory: " << s_alloc_bytes << " bytes in " << s_alloc_count << " allocations\n\n";
+
+    record rec = { label, 0, s_alloc_bytes, s_alloc_count };
+
+    test_contains( map, t1 );
+    test_count( map, t1 );
+    test_iteration( 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 );
+}
+
+// aliases using the counting allocator
+
+template<class K, class V> using allocator_for = ::allocator< std::pair<K const, V> >;
+
+template<class K, class V> using std_unordered_map =
+    std::unordered_map<K, V, std::hash<K>, std::equal_to<K>, allocator_for<K, V>>;
+
+template<class K, class V> using boost_unordered_map =
+    boost::unordered_map<K, V, boost::hash<K>, std::equal_to<K>, allocator_for<K, V>>;
+
+template<class K, class V> using boost_unordered_flat_map =
+    boost::unordered_flat_map<K, V, boost::hash<K>, std::equal_to<K>, allocator_for<K, V>>;
+
+#ifdef HAVE_ABSEIL
+
+template<class K, class V> using absl_node_hash_map =
+    absl::node_hash_map<K, V, absl::container_internal::hash_default_hash<K>, absl::container_internal::hash_default_eq<K>, allocator_for<K, V>>;
+
+template<class K, class V> using absl_flat_hash_map =
+    absl::flat_hash_map<K, V, absl::container_internal::hash_default_hash<K>, absl::container_internal::hash_default_eq<K>, allocator_for<K, V>>;
+
+#endif
+
+#ifdef HAVE_ANKERL_UNORDERED_DENSE
+
+template<class K, class V> using ankerl_unordered_dense_map =
+    ankerl::unordered_dense::map<K, V, ankerl::unordered_dense::hash<K>, std::equal_to<K>, ::allocator< std::pair<K, V> >>;
+
+#endif
+
+// 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;
+};
+
+template<class K, class V> using std_unordered_map_fnv1a =
+std::unordered_map<K, V, fnv1a_hash, std::equal_to<K>, allocator_for<K, V>>;
+
+template<class K, class V> using boost_unordered_map_fnv1a =
+    boost::unordered_map<K, V, fnv1a_hash, std::equal_to<K>, allocator_for<K, V>>;
+
+template<class K, class V> using boost_unordered_flat_map_fnv1a =
+    boost::unordered_flat_map<K, V, fnv1a_hash, std::equal_to<K>, allocator_for<K, V>>;
+
+#ifdef HAVE_ABSEIL
+
+template<class K, class V> using absl_node_hash_map_fnv1a =
+    absl::node_hash_map<K, V, fnv1a_hash, absl::container_internal::hash_default_eq<K>, allocator_for<K, V>>;
+
+template<class K, class V> using absl_flat_hash_map_fnv1a =
+    absl::flat_hash_map<K, V, fnv1a_hash, absl::container_internal::hash_default_eq<K>, allocator_for<K, V>>;
+
+#endif
+
+#ifdef HAVE_ANKERL_UNORDERED_DENSE
+
+template<class K, class V> using ankerl_unordered_dense_map_fnv1a =
+    ankerl::unordered_dense::map<K, V, fnv1a_hash, std::equal_to<K>, ::allocator< std::pair<K, V> >>;
+
+#endif
+
+//
+
+int main()
+{
+    init_words();
+
+    test<std_unordered_map>( "std::unordered_map" );
+    test<boost_unordered_map>( "boost::unordered_map" );
+    test<boost_unordered_flat_map>( "boost::unordered_flat_map" );
+
+#ifdef HAVE_ANKERL_UNORDERED_DENSE
+
+    test<ankerl_unordered_dense_map>( "ankerl::unordered_dense::map" );
+
+#endif
+
+#ifdef HAVE_ABSEIL
+
+    test<absl_node_hash_map>( "absl::node_hash_map" );
+    test<absl_flat_hash_map>( "absl::flat_hash_map" );
+
+#endif
+
+    test<std_unordered_map_fnv1a>( "std::unordered_map, FNV-1a" );
+    test<boost_unordered_map_fnv1a>( "boost::unordered_map, FNV-1a" );
+    test<boost_unordered_flat_map_fnv1a>( "boost::unordered_flat_map, FNV-1a" );
+
+#ifdef HAVE_ANKERL_UNORDERED_DENSE
+
+    test<ankerl_unordered_dense_map_fnv1a>( "ankerl::unordered_dense::map, FNV-1a" );
+
+#endif
+
+#ifdef HAVE_ABSEIL
+
+    test<absl_node_hash_map_fnv1a>( "absl::node_hash_map, FNV-1a" );
+    test<absl_flat_hash_map_fnv1a>( "absl::flat_hash_map, FNV-1a" );
+
+#endif
+
+    std::cout << "---\n\n";
+
+    for( auto const& x: times )
+    {
+        std::cout << std::setw( 38 ) << ( x.label_ + ": " ) << std::setw( 5 ) << x.time_ << " ms, " << std::setw( 9 ) << x.bytes_ << " bytes in " << x.count_ << " allocations\n";
+    }
+}
+
+#ifdef HAVE_ABSEIL
+# include "absl/container/internal/raw_hash_set.cc"
+# include "absl/hash/internal/hash.cc"
+# include "absl/hash/internal/low_level_hash.cc"
+# include "absl/hash/internal/city.cc"
+#endif

benchmark/word_size.cpp

@@ -0,0 +1,238 @@
+// Copyright 2021, 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_map.hpp>
+#include <boost/unordered/unordered_flat_map.hpp>
+#include <boost/regex.hpp>
+#ifdef HAVE_ABSEIL
+# include "absl/container/node_hash_map.h"
+# include "absl/container/flat_hash_map.h"
+#endif
+#ifdef HAVE_ANKERL_UNORDERED_DENSE
+# include "ankerl/unordered_dense.h"
+#endif
+#include <unordered_map>
+#include <vector>
+#include <memory>
+#include <cstdint>
+#include <iostream>
+#include <iomanip>
+#include <chrono>
+#include <fstream>
+
+using namespace std::chrono_literals;
+
+static void print_time( std::chrono::steady_clock::time_point & t1, char const* label, std::size_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_size( Map& map, std::chrono::steady_clock::time_point & t1 )
+{
+    for( auto const& word: words )
+    {
+        ++map[ word.size() ];
+    }
+
+    print_time( t1, "Word size count",  0, map.size() );
+
+    std::cout << std::endl;
+}
+
+template<class Map> BOOST_NOINLINE void test_iteration( Map& map, std::chrono::steady_clock::time_point & t1 )
+{
+    std::size_t s = 0;
+
+    for( auto const& x: map )
+    {
+        s += x.second;
+    }
+
+    print_time( t1, "Iterate and sum counts",  s, map.size() );
+
+    std::cout << std::endl;
+}
+
+// counting allocator
+
+static std::size_t s_alloc_bytes = 0;
+static std::size_t s_alloc_count = 0;
+
+template<class T> struct allocator
+{
+    using value_type = T;
+
+    allocator() = default;
+
+    template<class U> allocator( allocator<U> const & ) noexcept
+    {
+    }
+
+    template<class U> bool operator==( allocator<U> const & ) const noexcept
+    {
+        return true;
+    }
+
+    template<class U> bool operator!=( allocator<U> const& ) const noexcept
+    {
+        return false;
+    }
+
+    T* allocate( std::size_t n ) const
+    {
+        s_alloc_bytes += n * sizeof(T);
+        s_alloc_count++;
+
+        return std::allocator<T>().allocate( n );
+    }
+
+    void deallocate( T* p, std::size_t n ) const noexcept
+    {
+        s_alloc_bytes -= n * sizeof(T);
+        s_alloc_count--;
+
+        std::allocator<T>().deallocate( p, n );
+    }
+};
+
+//
+
+struct record
+{
+    std::string label_;
+    long long time_;
+    std::size_t bytes_;
+    std::size_t count_;
+};
+
+static std::vector<record> times;
+
+template<template<class...> class Map> BOOST_NOINLINE void test( char const* label )
+{
+    std::cout << label << ":\n\n";
+
+    s_alloc_bytes = 0;
+    s_alloc_count = 0;
+
+    Map<std::size_t, std::size_t> map;
+
+    auto t0 = std::chrono::steady_clock::now();
+    auto t1 = t0;
+
+    test_word_size( map, t1 );
+
+    std::cout << "Memory: " << s_alloc_bytes << " bytes in " << s_alloc_count << " allocations\n\n";
+
+    record rec = { label, 0, s_alloc_bytes, s_alloc_count };
+
+    test_iteration( 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 );
+}
+
+// aliases using the counting allocator
+
+template<class K, class V> using allocator_for = ::allocator< std::pair<K const, V> >;
+
+template<class K, class V> using std_unordered_map =
+    std::unordered_map<K, V, std::hash<K>, std::equal_to<K>, allocator_for<K, V>>;
+
+template<class K, class V> using boost_unordered_map =
+    boost::unordered_map<K, V, boost::hash<K>, std::equal_to<K>, allocator_for<K, V>>;
+
+template<class K, class V> using boost_unordered_flat_map =
+    boost::unordered_flat_map<K, V, boost::hash<K>, std::equal_to<K>, allocator_for<K, V>>;
+
+#ifdef HAVE_ABSEIL
+
+template<class K, class V> using absl_node_hash_map =
+    absl::node_hash_map<K, V, absl::container_internal::hash_default_hash<K>, absl::container_internal::hash_default_eq<K>, allocator_for<K, V>>;
+
+template<class K, class V> using absl_flat_hash_map =
+    absl::flat_hash_map<K, V, absl::container_internal::hash_default_hash<K>, absl::container_internal::hash_default_eq<K>, allocator_for<K, V>>;
+
+#endif
+
+#ifdef HAVE_ANKERL_UNORDERED_DENSE
+
+template<class K, class V> using ankerl_unordered_dense_map =
+    ankerl::unordered_dense::map<K, V, ankerl::unordered_dense::hash<K>, std::equal_to<K>, ::allocator< std::pair<K, V> >>;
+
+#endif
+
+int main()
+{
+    init_words();
+
+    test<std_unordered_map>( "std::unordered_map" );
+    test<boost_unordered_map>( "boost::unordered_map" );
+    test<boost_unordered_flat_map>( "boost::unordered_flat_map" );
+
+#ifdef HAVE_ANKERL_UNORDERED_DENSE
+
+    test<ankerl_unordered_dense_map>( "ankerl::unordered_dense::map" );
+
+#endif
+
+#ifdef HAVE_ABSEIL
+
+    test<absl_node_hash_map>( "absl::node_hash_map" );
+    test<absl_flat_hash_map>( "absl::flat_hash_map" );
+
+#endif
+
+    std::cout << "---\n\n";
+
+    for( auto const& x: times )
+    {
+        std::cout << std::setw( 30 ) << ( x.label_ + ": " ) << std::setw( 5 ) << x.time_ << " ms, " << std::setw( 9 ) << x.bytes_ << " bytes in " << x.count_ << " allocations\n";
+    }
+}
+
+#ifdef HAVE_ABSEIL
+# include "absl/container/internal/raw_hash_set.cc"
+# include "absl/hash/internal/hash.cc"
+# include "absl/hash/internal/low_level_hash.cc"
+# include "absl/hash/internal/city.cc"
+#endif