docs: updated copyright notice

Merge branch 'develop'
Merge pull request #91 from sdarwin/githubactions
2025-07-15 13:26:37 +02:00 · 2021-03-10 23:07:18 +01:00 · 2021-03-10 23:01:22 +01:00 · 2021-03-03 16:13:06 +01:00 · 2021-03-03 14:56:21 +00:00 · 2021-01-21 21:18:22 +01:00
102 changed files with 844 additions and 191 deletions
--- a/.drone.star
+++ b/.drone.star
@ -0,0 +1,36 @@
+# Use, modification, and distribution are
+# subject to the Boost Software License, Version 1.0. (See accompanying
+# file LICENSE.txt)
+#
+# Copyright Rene Rivera 2020.
+
+# For Drone CI we use the Starlark scripting language to reduce duplication.
+# As the yaml syntax for Drone CI is rather limited.
+#
+#
+globalenv={}
+linuxglobalimage="cppalliance/droneubuntu1604:1"
+windowsglobalimage="cppalliance/dronevs2019"
+
+def main(ctx):
+  return [
+  linux_cxx("TOOLSET=gcc COMPILER=g++ CXXSTD=03,11 Job 0", "g++", packages="", buildtype="boost", buildscript="drone", image=linuxglobalimage, environment={'TOOLSET': 'gcc', 'COMPILER': 'g++', 'CXXSTD': '03,11', 'DRONE_JOB_UUID': 'b6589fc6ab'}, globalenv=globalenv),
+  linux_cxx("TOOLSET=gcc COMPILER=g++-4.7 CXXSTD=03,11 Job 1", "g++-4.7", packages="g++-4.7", buildtype="boost", buildscript="drone", image=linuxglobalimage, environment={'TOOLSET': 'gcc', 'COMPILER': 'g++-4.7', 'CXXSTD': '03,11', 'DRONE_JOB_UUID': '356a192b79'}, globalenv=globalenv),
+  linux_cxx("TOOLSET=gcc COMPILER=g++-4.8 CXXSTD=03,11 Job 2", "g++-4.8", packages="g++-4.8", buildtype="boost", buildscript="drone", image=linuxglobalimage, environment={'TOOLSET': 'gcc', 'COMPILER': 'g++-4.8', 'CXXSTD': '03,11', 'DRONE_JOB_UUID': 'da4b9237ba'}, globalenv=globalenv),
+  linux_cxx("TOOLSET=gcc COMPILER=g++-4.9 CXXSTD=03,11 Job 3", "g++-4.9", packages="g++-4.9", buildtype="boost", buildscript="drone", image=linuxglobalimage, environment={'TOOLSET': 'gcc', 'COMPILER': 'g++-4.9', 'CXXSTD': '03,11', 'DRONE_JOB_UUID': '77de68daec'}, globalenv=globalenv),
+  linux_cxx("TOOLSET=gcc COMPILER=g++-5 CXXSTD=03,11,14,1z Job 4", "g++-5", packages="g++-5", buildtype="boost", buildscript="drone", image=linuxglobalimage, environment={'TOOLSET': 'gcc', 'COMPILER': 'g++-5', 'CXXSTD': '03,11,14,1z', 'DRONE_JOB_UUID': '1b64538924'}, globalenv=globalenv),
+  linux_cxx("TOOLSET=gcc COMPILER=g++-6 CXXSTD=03,11,14,1z Job 5", "g++-6", packages="g++-6", buildtype="boost", buildscript="drone", image=linuxglobalimage, environment={'TOOLSET': 'gcc', 'COMPILER': 'g++-6', 'CXXSTD': '03,11,14,1z', 'DRONE_JOB_UUID': 'ac3478d69a'}, globalenv=globalenv),
+  linux_cxx("TOOLSET=gcc COMPILER=g++-7 CXXSTD=03,11,14,17 Job 6", "g++-7", packages="g++-7", buildtype="boost", buildscript="drone", image="cppalliance/droneubuntu1404:1", environment={'TOOLSET': 'gcc', 'COMPILER': 'g++-7', 'CXXSTD': '03,11,14,17', 'DRONE_JOB_UUID': 'c1dfd96eea'}, globalenv=globalenv),
+  linux_cxx("TOOLSET=clang COMPILER=clang++ CXXSTD=03,11 Job 7", "clang++", packages="", buildtype="boost", buildscript="drone", image=linuxglobalimage, environment={'TOOLSET': 'clang', 'COMPILER': 'clang++', 'CXXSTD': '03,11', 'DRONE_JOB_UUID': '902ba3cda1'}, globalenv=globalenv),
+  linux_cxx("TOOLSET=clang COMPILER=clang++-3.5 CXXSTD=03, Job 8", "clang++-3.5", packages="clang-3.5 libstdc++-4.9-dev", llvm_os="precise", llvm_ver="3.5", buildtype="boost", buildscript="drone", image=linuxglobalimage, environment={'TOOLSET': 'clang', 'COMPILER': 'clang++-3.5', 'CXXSTD': '03,11,14,1z', 'DRONE_JOB_UUID': 'fe5dbbcea5'}, globalenv=globalenv),
+  linux_cxx("TOOLSET=clang COMPILER=clang++-3.6 CXXSTD=03, Job 9", "clang++-3.6", packages="clang-3.6", llvm_os="precise", llvm_ver="3.6", buildtype="boost", buildscript="drone", image=linuxglobalimage, environment={'TOOLSET': 'clang', 'COMPILER': 'clang++-3.6', 'CXXSTD': '03,11,14,1z', 'DRONE_JOB_UUID': '0ade7c2cf9'}, globalenv=globalenv),
+  linux_cxx("TOOLSET=clang COMPILER=clang++-3.7 CXXSTD=03, Job 10", "clang++-3.7", packages="clang-3.7", llvm_os="precise", llvm_ver="3.7", buildtype="boost", buildscript="drone", image=linuxglobalimage, environment={'TOOLSET': 'clang', 'COMPILER': 'clang++-3.7', 'CXXSTD': '03,11,14,1z', 'DRONE_JOB_UUID': 'b1d5781111'}, globalenv=globalenv),
+  linux_cxx("TOOLSET=clang COMPILER=clang++-3.8 CXXSTD=03, Job 11", "clang++-3.8", packages="clang-3.8 libstdc++-4.9-dev", llvm_os="precise", llvm_ver="3.8", buildtype="boost", buildscript="drone", image=linuxglobalimage, environment={'TOOLSET': 'clang', 'COMPILER': 'clang++-3.8', 'CXXSTD': '03,11,14,1z', 'DRONE_JOB_UUID': '17ba079149'}, globalenv=globalenv),
+  linux_cxx("TOOLSET=clang COMPILER=clang++-3.9 CXXSTD=03, Job 12", "clang++-3.9", packages="clang-3.9 libstdc++-4.9-dev", llvm_os="precise", llvm_ver="3.9", buildtype="boost", buildscript="drone", image=linuxglobalimage, environment={'TOOLSET': 'clang', 'COMPILER': 'clang++-3.9', 'CXXSTD': '03,11,14,1z', 'DRONE_JOB_UUID': '7b52009b64'}, globalenv=globalenv),
+  linux_cxx("TOOLSET=clang COMPILER=clang++-4.0 CXXSTD=03, Job 13", "clang++-4.0", packages="clang-4.0", llvm_os="trusty", llvm_ver="4.0", buildtype="boost", buildscript="drone", image="cppalliance/droneubuntu1404:1", environment={'TOOLSET': 'clang', 'COMPILER': 'clang++-4.0', 'CXXSTD': '03,11,14,1z', 'DRONE_JOB_UUID': 'bd307a3ec3'}, globalenv=globalenv),
+  linux_cxx("TOOLSET=clang COMPILER=clang++-5.0 CXXSTD=03, Job 14", "clang++-5.0", packages="clang-5.0", llvm_os="trusty", llvm_ver="5.0", buildtype="boost", buildscript="drone", image="cppalliance/droneubuntu1404:1", environment={'TOOLSET': 'clang', 'COMPILER': 'clang++-5.0', 'CXXSTD': '03,11,14,1z', 'DRONE_JOB_UUID': 'fa35e19212'}, globalenv=globalenv),
+  osx_cxx("TOOLSET=clang COMPILER=clang++ CXXSTD=03,11,1 Job 15", "clang++", packages="", buildtype="boost", buildscript="drone", environment={'TOOLSET': 'clang', 'COMPILER': 'clang++', 'CXXSTD': '03,11,14,1z', 'DRONE_JOB_UUID': 'f1abd67035'}, globalenv=globalenv),
+    ]
+
+# from https://github.com/boostorg/boost-ci
+load("@boost_ci//ci/drone/:functions.star", "linux_cxx","windows_cxx","osx_cxx","freebsd_cxx")
--- a/.drone/drone.sh
+++ b/.drone/drone.sh
@ -0,0 +1,37 @@
+#!/bin/bash
+
+# Copyright 2020 Rene Rivera, Sam Darwin
+# Distributed under the Boost Software License, Version 1.0.
+# (See accompanying file LICENSE.txt or copy at http://boost.org/LICENSE_1_0.txt)
+
+set -e
+export TRAVIS_BUILD_DIR=$(pwd)
+export DRONE_BUILD_DIR=$(pwd)
+export TRAVIS_BRANCH=$DRONE_BRANCH
+export VCS_COMMIT_ID=$DRONE_COMMIT
+export GIT_COMMIT=$DRONE_COMMIT
+export REPO_NAME=$DRONE_REPO
+export PATH=~/.local/bin:/usr/local/bin:$PATH
+
+if [ "$DRONE_JOB_BUILDTYPE" == "boost" ]; then
+
+echo '==================================> INSTALL'
+
+BOOST_BRANCH=develop && [ "$TRAVIS_BRANCH" == "master" ] && BOOST_BRANCH=master || true
+cd ..
+git clone -b $BOOST_BRANCH --depth 1 https://github.com/boostorg/boost.git boost-root
+cd boost-root
+git submodule update --init tools/build
+git submodule update --init libs/config
+git submodule update --init tools/boostdep
+cp -r $TRAVIS_BUILD_DIR/* libs/optional
+python tools/boostdep/depinst/depinst.py optional
+./bootstrap.sh
+./b2 headers
+
+echo '==================================> SCRIPT'
+
+echo "using $TOOLSET : : $COMPILER ;" > ~/user-config.jam
+./b2 libs/optional/test toolset=$TOOLSET cxxstd=$CXXSTD
+
+fi
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@ -0,0 +1,377 @@
+name: GitHub Actions CI
+
+on:
+  pull_request:
+  push:
+    branches:
+      - master
+      - develop
+      - githubactions*
+      - feature/**
+      - fix/**
+      - pr/**
+
+jobs:
+  posix:
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - name: "TOOLSET=gcc COMPILER=g++ CXXSTD=03,11 Job 0"
+            buildtype: "boost"
+            packages: ""
+            packages_to_remove: ""
+            os: "ubuntu-16.04"
+            cxx: "g++"
+            sources: ""
+            llvm_os: ""
+            llvm_ver: ""
+            toolset: "gcc"
+            compiler: "g++"
+            cxxstd: "03,11"
+          - name: "TOOLSET=gcc COMPILER=g++-4.7 CXXSTD=03,11 Job 1"
+            buildtype: "boost"
+            packages: "g++-4.7"
+            packages_to_remove: ""
+            os: "ubuntu-16.04"
+            cxx: "g++-4.7"
+            sources: ""
+            llvm_os: ""
+            llvm_ver: ""
+            toolset: "gcc"
+            compiler: "g++-4.7"
+            cxxstd: "03,11"
+          - name: "TOOLSET=gcc COMPILER=g++-4.8 CXXSTD=03,11 Job 2"
+            buildtype: "boost"
+            packages: "g++-4.8"
+            packages_to_remove: ""
+            os: "ubuntu-16.04"
+            cxx: "g++-4.8"
+            sources: ""
+            llvm_os: ""
+            llvm_ver: ""
+            toolset: "gcc"
+            compiler: "g++-4.8"
+            cxxstd: "03,11"
+          - name: "TOOLSET=gcc COMPILER=g++-4.9 CXXSTD=03,11 Job 3"
+            buildtype: "boost"
+            packages: "g++-4.9"
+            packages_to_remove: ""
+            os: "ubuntu-16.04"
+            cxx: "g++-4.9"
+            sources: ""
+            llvm_os: ""
+            llvm_ver: ""
+            toolset: "gcc"
+            compiler: "g++-4.9"
+            cxxstd: "03,11"
+          - name: "TOOLSET=gcc COMPILER=g++-5 CXXSTD=03,11,14,1z Job 4"
+            buildtype: "boost"
+            packages: "g++-5"
+            packages_to_remove: ""
+            os: "ubuntu-16.04"
+            cxx: "g++-5"
+            sources: ""
+            llvm_os: ""
+            llvm_ver: ""
+            toolset: "gcc"
+            compiler: "g++-5"
+            cxxstd: "03,11,14,1z"
+          - name: "TOOLSET=gcc COMPILER=g++-6 CXXSTD=03,11,14,1z Job 5"
+            buildtype: "boost"
+            packages: "g++-6"
+            packages_to_remove: ""
+            os: "ubuntu-16.04"
+            cxx: "g++-6"
+            sources: ""
+            llvm_os: ""
+            llvm_ver: ""
+            toolset: "gcc"
+            compiler: "g++-6"
+            cxxstd: "03,11,14,1z"
+          - name: "TOOLSET=gcc COMPILER=g++-7 CXXSTD=03,11,14,17 Job 6"
+            buildtype: "boost"
+            packages: "g++-7"
+            packages_to_remove: ""
+            os: "ubuntu-16.04"
+            cxx: "g++-7"
+            sources: ""
+            llvm_os: ""
+            llvm_ver: ""
+            toolset: "gcc"
+            compiler: "g++-7"
+            cxxstd: "03,11,14,17"
+          - name: "TOOLSET=clang COMPILER=clang++ CXXSTD=03,11 Job 7"
+            buildtype: "boost"
+            packages: ""
+            packages_to_remove: ""
+            os: "ubuntu-16.04"
+            cxx: "clang++"
+            sources: ""
+            llvm_os: ""
+            llvm_ver: ""
+            toolset: "clang"
+            compiler: "clang++"
+            cxxstd: "03,11"
+          - name: "TOOLSET=clang COMPILER=clang++-3.5 CXXSTD=03, Job 8"
+            buildtype: "boost"
+            packages: "clang-3.5 libstdc++-4.9-dev"
+            packages_to_remove: ""
+            os: "ubuntu-16.04"
+            cxx: "clang++-3.5"
+            sources: ""
+            llvm_os: "precise"
+            llvm_ver: "3.5"
+            toolset: "clang"
+            compiler: "clang++-3.5"
+            cxxstd: "03,11,14"
+          - name: "TOOLSET=clang COMPILER=clang++-3.6 CXXSTD=03, Job 9"
+            buildtype: "boost"
+            packages: "clang-3.6"
+            packages_to_remove: ""
+            os: "ubuntu-16.04"
+            cxx: "clang++-3.6"
+            sources: ""
+            llvm_os: "precise"
+            llvm_ver: "3.6"
+            toolset: "clang"
+            compiler: "clang++-3.6"
+            cxxstd: "03,11,14"
+          - name: "TOOLSET=clang COMPILER=clang++-3.7 CXXSTD=03, Job 10"
+            buildtype: "boost"
+            packages: "clang-3.7"
+            packages_to_remove: ""
+            os: "ubuntu-16.04"
+            cxx: "clang++-3.7"
+            sources: ""
+            llvm_os: "precise"
+            llvm_ver: "3.7"
+            toolset: "clang"
+            compiler: "clang++-3.7"
+            cxxstd: "03,11,14"
+          - name: "TOOLSET=clang COMPILER=clang++-3.8 CXXSTD=03, Job 11"
+            buildtype: "boost"
+            packages: "clang-3.8 libstdc++-4.9-dev"
+            packages_to_remove: ""
+            os: "ubuntu-16.04"
+            cxx: "clang++-3.8"
+            sources: ""
+            llvm_os: "precise"
+            llvm_ver: "3.8"
+            toolset: "clang"
+            compiler: "clang++-3.8"
+            cxxstd: "03,11,14"
+          - name: "TOOLSET=clang COMPILER=clang++-3.9 CXXSTD=03, Job 12"
+            buildtype: "boost"
+            packages: "clang-3.9 libstdc++-4.9-dev"
+            packages_to_remove: ""
+            os: "ubuntu-16.04"
+            cxx: "clang++-3.9"
+            sources: ""
+            llvm_os: "precise"
+            llvm_ver: "3.9"
+            toolset: "clang"
+            compiler: "clang++-3.9"
+            cxxstd: "03,11,14"
+          - name: "TOOLSET=clang COMPILER=clang++-4.0 CXXSTD=03, Job 13"
+            buildtype: "boost"
+            packages: "clang-4.0"
+            packages_to_remove: ""
+            os: "ubuntu-16.04"
+            container: "ubuntu:14.04"
+            cxx: "clang++-4.0"
+            sources: ""
+            llvm_os: "trusty"
+            llvm_ver: "4.0"
+            toolset: "clang"
+            compiler: "clang++-4.0"
+            cxxstd: "03,11,14"
+          - name: "TOOLSET=clang COMPILER=clang++-5.0 CXXSTD=03, Job 14"
+            buildtype: "boost"
+            packages: "clang-5.0"
+            packages_to_remove: ""
+            os: "ubuntu-16.04"
+            container: "ubuntu:14.04"
+            cxx: "clang++-5.0"
+            sources: ""
+            llvm_os: "trusty"
+            llvm_ver: "5.0"
+            toolset: "clang"
+            compiler: "clang++-5.0"
+            cxxstd: "03,11,14,1z"
+
+    runs-on: ${{ matrix.os }}
+    container: ${{ matrix.container }}
+
+    steps:
+      - name: Check if running in container
+        if: matrix.container != ''
+        run: echo "GHA_CONTAINER=${{ matrix.container }}" >> $GITHUB_ENV
+      - name: If running in container, upgrade packages
+        if: matrix.container != ''
+        run: |
+            sudo apt-get -o Acquire::Retries=3 update && DEBIAN_FRONTEND=noninteractive apt-get -y install tzdata && apt-get -o Acquire::Retries=3 install -y sudo software-properties-common wget curl apt-transport-https make apt-file sudo unzip libssl-dev build-essential autotools-dev autoconf automake g++ libc++-helpers python python-pip ruby cpio gcc-multilib g++-multilib pkgconf python3 python3-pip ccache libpython-dev
+            sudo apt-add-repository ppa:git-core/ppa
+            sudo apt-get -o Acquire::Retries=3 update && apt-get -o Acquire::Retries=3 -y install git
+            sudo python -m pip install --upgrade pip==20.3.4
+            sudo /usr/local/bin/pip install cmake
+
+      - uses: actions/checkout@v2
+
+      - name: linux
+        shell: bash
+        env:
+          CXX: ${{ matrix.cxx }}
+          SOURCES: ${{ matrix.sources }}
+          LLVM_OS: ${{ matrix.llvm_os }}
+          LLVM_VER: ${{ matrix.llvm_ver }}
+          PACKAGES: ${{ matrix.packages }}
+          PACKAGES_TO_REMOVE: ${{ matrix.packages_to_remove }}
+          JOB_BUILDTYPE: ${{ matrix.buildtype }}
+          TOOLSET: ${{ matrix.toolset }}
+          COMPILER: ${{ matrix.compiler }}
+          CXXSTD: ${{ matrix.cxxstd }}
+          TRAVIS_BRANCH: ${{ github.base_ref }}
+          TRAVIS_OS_NAME: "linux"
+        run: |
+          echo '==================================> SETUP'
+          echo '==================================> PACKAGES'
+          set -e
+          if [ -n "$PACKAGES_TO_REMOVE" ]; then sudo apt-get purge -y $PACKAGES_TO_REMOVE; fi
+          echo ">>>>> APT: REPO.."
+          for i in {1..3}; do sudo -E apt-add-repository -y "ppa:ubuntu-toolchain-r/test" && break || sleep 2; done
+          
+          if test -n "${LLVM_OS}" ; then
+              wget -O - https://apt.llvm.org/llvm-snapshot.gpg.key | sudo apt-key add -
+              if test -n "${LLVM_VER}" ; then
+                  sudo -E apt-add-repository "deb http://apt.llvm.org/${LLVM_OS}/ llvm-toolchain-${LLVM_OS}-${LLVM_VER} main"
+              else
+                  # Snapshot (i.e. trunk) build of clang
+                  sudo -E apt-add-repository "deb http://apt.llvm.org/${LLVM_OS}/ llvm-toolchain-${LLVM_OS} main"
+              fi
+          fi
+          echo ">>>>> APT: UPDATE.."
+          sudo -E apt-get -o Acquire::Retries=3 update
+          if test -n "${SOURCES}" ; then
+              echo ">>>>> APT: INSTALL SOURCES.."
+              for SOURCE in $SOURCES; do
+                  sudo -E apt-add-repository ppa:$SOURCE
+              done
+          fi
+          echo ">>>>> APT: INSTALL ${PACKAGES}.."
+          sudo -E DEBIAN_FRONTEND=noninteractive apt-get -o Acquire::Retries=3 -y --no-install-suggests --no-install-recommends install ${PACKAGES}
+
+          echo '==================================> INSTALL AND COMPILE'
+          set -e
+          export TRAVIS_BUILD_DIR=$(pwd)
+          export TRAVIS_BRANCH=${TRAVIS_BRANCH:-$(echo $GITHUB_REF | awk 'BEGIN { FS = "/" } ; { print $3 }')}
+          export VCS_COMMIT_ID=$GITHUB_SHA
+          export GIT_COMMIT=$GITHUB_SHA
+          export REPO_NAME=$(basename $GITHUB_REPOSITORY)
+          export USER=$(whoami)
+          export CC=${CC:-gcc}
+          export PATH=~/.local/bin:/usr/local/bin:$PATH
+
+          if [ "$JOB_BUILDTYPE" == "boost" ]; then
+
+          echo '==================================> INSTALL'
+
+          BOOST_BRANCH=develop && [ "$TRAVIS_BRANCH" == "master" ] && BOOST_BRANCH=master || true
+          cd ..
+          git clone -b $BOOST_BRANCH --depth 1 https://github.com/boostorg/boost.git boost-root
+          cd boost-root
+          git submodule update --init tools/build
+          git submodule update --init libs/config
+          git submodule update --init tools/boostdep
+          cp -r $TRAVIS_BUILD_DIR/* libs/optional
+          python tools/boostdep/depinst/depinst.py optional
+          ./bootstrap.sh
+          ./b2 headers
+
+          echo '==================================> SCRIPT'
+
+          echo "using $TOOLSET : : $COMPILER ;" > ~/user-config.jam
+          ./b2 libs/optional/test toolset=$TOOLSET cxxstd=$CXXSTD
+
+          fi
+  osx:
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - name: "TOOLSET=clang COMPILER=clang++ CXXSTD=03,11,1 Job 15"
+            buildtype: "boost"
+            packages: ""
+            os: "macos-10.15"
+            cxx: "clang++"
+            sources: ""
+            llvm_os: ""
+            llvm_ver: ""
+            xcode_version: 11.7
+            toolset: "clang"
+            compiler: "clang++"
+            cxxstd: "03,11,14,1z"
+
+    runs-on: ${{ matrix.os }}
+
+    steps:
+      - uses: actions/checkout@v2
+
+      - name: Set DEVELOPER_DIR
+        if: matrix.xcode_version != ''
+        run: echo "DEVELOPER_DIR=/Applications/Xcode_${{ matrix.xcode_version }}.app/Contents/Developer" >> $GITHUB_ENV
+      - name: Test DEVELOPER_DIR
+        run: echo $DEVELOPER_DIR
+
+      - name: "osx"
+        shell: bash
+        env:
+          CXX: ${{ matrix.cxx }}
+          SOURCES: ${{ matrix.sources }}
+          LLVM_OS: ${{ matrix.llvm_os }}
+          LLVM_VER: ${{ matrix.llvm_ver }}
+          PACKAGES: ${{ matrix.packages }}
+          JOB_BUILDTYPE: ${{ matrix.buildtype }}
+          TOOLSET: ${{ matrix.toolset }}
+          COMPILER: ${{ matrix.compiler }}
+          CXXSTD: ${{ matrix.cxxstd }}
+          TRAVIS_BRANCH: ${{ github.base_ref }}
+          TRAVIS_OS_NAME: "osx"
+        run: |
+          echo '==================================> SETUP'
+          set -e
+          sudo mv /Library/Developer/CommandLineTools /Library/Developer/CommandLineTools.bck
+          echo '==================================> PACKAGES'
+          echo '==================================> INSTALL AND COMPILE'
+          set -e
+          export TRAVIS_BUILD_DIR=$(pwd)
+          export TRAVIS_BRANCH=${TRAVIS_BRANCH:-$(echo $GITHUB_REF | awk 'BEGIN { FS = "/" } ; { print $3 }')}
+          export VCS_COMMIT_ID=$GITHUB_SHA
+          export GIT_COMMIT=$GITHUB_SHA
+          export REPO_NAME=$(basename $GITHUB_REPOSITORY)
+          export USER=$(whoami)
+          export CC=${CC:-gcc}
+          export PATH=~/.local/bin:/usr/local/bin:$PATH
+
+          if [ "$JOB_BUILDTYPE" == "boost" ]; then
+
+          echo '==================================> INSTALL'
+
+          BOOST_BRANCH=develop && [ "$TRAVIS_BRANCH" == "master" ] && BOOST_BRANCH=master || true
+          cd ..
+          git clone -b $BOOST_BRANCH --depth 1 https://github.com/boostorg/boost.git boost-root
+          cd boost-root
+          git submodule update --init tools/build
+          git submodule update --init libs/config
+          git submodule update --init tools/boostdep
+          cp -r $TRAVIS_BUILD_DIR/* libs/optional
+          python tools/boostdep/depinst/depinst.py optional
+          ./bootstrap.sh
+          ./b2 headers
+
+          echo '==================================> SCRIPT'
+
+          echo "using $TOOLSET : : $COMPILER ;" > ~/user-config.jam
+          ./b2 libs/optional/test toolset=$TOOLSET cxxstd=$CXXSTD
+
+          fi
--- a/.travis.yml
+++ b/.travis.yml
@ -151,6 +151,7 @@ matrix:
            - llvm-toolchain-precise-3.9

    - os: linux
+      dist: trusty
      compiler: clang++-4.0
      env: TOOLSET=clang COMPILER=clang++-4.0 CXXSTD=03,11,14,1z
      addons:
@ -162,6 +163,7 @@ matrix:
            - llvm-toolchain-trusty-4.0

    - os: linux
+      dist: trusty
      compiler: clang++-5.0
      env: TOOLSET=clang COMPILER=clang++-5.0 CXXSTD=03,11,14,1z
      addons:
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@ -0,0 +1,28 @@
+# Copyright 2019 Mike Dev
+# Distributed under the Boost Software License, Version 1.0.
+# See accompanying file LICENSE_1_0.txt or copy at https://www.boost.org/LICENSE_1_0.txt
+#
+# NOTE: CMake support for Boost.Optional is currently experimental at best
+#       and the interface is likely to change in the future
+
+cmake_minimum_required( VERSION 3.5 )
+project( BoostOptional )
+
+add_library( boost_optional INTERFACE )
+add_library( Boost::optional ALIAS boost_optional )
+
+target_include_directories( boost_optional INTERFACE include )
+
+target_link_libraries( boost_optional
+    INTERFACE
+        Boost::assert
+        Boost::config
+        Boost::core
+        Boost::detail
+        Boost::move
+        Boost::predef
+        Boost::static_assert
+        Boost::throw_exception
+        Boost::type_traits
+        Boost::utility
+)
--- a/doc/00_optional.qbk
+++ b/doc/00_optional.qbk
@ -2,7 +2,7 @@
    [quickbook 1.4]
    [authors [Cacciola Carballal, Fernando Luis]]
    [copyright 2003-2007 Fernando Luis Cacciola Carballal]
-    [copyright 2014-2018 Andrzej Krzemie&#324;ski]
+    [copyright 2014-2021 Andrzej Krzemie&#324;ski]
    [category miscellaneous]
    [id optional]
    [dirname optional]
@ -61,7 +61,7 @@ Suppose we want to read a parameter form a config file which represents some int
 This is how you solve it with `boost::optional`:

    #include <boost/optional.hpp>
-    
+
    boost::optional<int> getConfigParam(std::string name);  // return either an int or a `not-an-int`

    int main()
@ -71,7 +71,7 @@ This is how you solve it with `boost::optional`:
      else
        runWithNoMax();
    }
- 
+
 [endsect]

 [include 01_quick_start.qbk]
@ -102,5 +102,3 @@ This is how you solve it with `boost::optional`:
 [include 90_dependencies.qbk]
 [include 91_relnotes.qbk]
 [include 92_acknowledgments.qbk]
-
-
--- a/doc/21_ref_none.qbk
+++ b/doc/21_ref_none.qbk
@ -17,8 +17,8 @@ namespace boost {

 class none_t {/* see below */};

-const none_t none (/* see below */); 
-    
+inline constexpr none_t none (/* see below */);
+
 } // namespace boost
 ```

--- a/doc/91_relnotes.qbk
+++ b/doc/91_relnotes.qbk
@ -11,11 +11,28 @@

 [section:relnotes Release Notes]

+[heading Boost Release 1.76]
+
+* Fixed MSVC warning C4702.
+
+[heading Boost Release 1.75]
+
+* `boost::none` is `constexpr`-declared.
+
+* Fixed [@https://github.com/boostorg/optional/issues/78 issue #78].
+
+[heading Boost Release 1.73]
+
+* Fixed [@https://github.com/boostorg/optional/issues/78 issue #78].
+* `boost::none` is now declared as an inline variable (on compilers that support it): there is only one instance of `boost::none` across all translation units.
+* Fixed a number of compilation errors in GCC 4.4.7 in `optional<T>` for trivial `T`s. Thanks to Robert Leahy for the fix. For details see [@https://github.com/boostorg/optional/pull/80 pr #78].
+* Now surpressing warning `-Wweak-vtables`.
+
 [heading Boost Release 1.69]

 * Remove deprecation mark from `reset()` method (without arguments).
 * Fixed [@https://github.com/boostorg/optional/issues/59 issue #59].
-* Fixed bug with initialization of certain wrapper types in clang with -std=c++03. See [@https://github.com/boostorg/optional/pull/64 pr #64]. 
+* Fixed bug with initialization of certain wrapper types in clang with -std=c++03. See [@https://github.com/boostorg/optional/pull/64 pr #64].

 [heading Boost Release 1.68]

--- a/doc/html/boost_optional/acknowledgements.html
+++ b/doc/html/boost_optional/acknowledgements.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>Acknowledgements</title>
 <link rel="stylesheet" href="../../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -116,7 +116,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
--- a/doc/html/boost_optional/dependencies_and_portability.html
+++ b/doc/html/boost_optional/dependencies_and_portability.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>Dependencies and Portability</title>
 <link rel="stylesheet" href="../../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -77,7 +77,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
--- a/doc/html/boost_optional/dependencies_and_portability/emplace_operations_in_older_compilers.html
+++ b/doc/html/boost_optional/dependencies_and_portability/emplace_operations_in_older_compilers.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>Emplace operations in older compilers</title>
 <link rel="stylesheet" href="../../../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -76,7 +76,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
--- a/doc/html/boost_optional/dependencies_and_portability/optional_reference_binding.html
+++ b/doc/html/boost_optional/dependencies_and_portability/optional_reference_binding.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>Optional Reference Binding</title>
 <link rel="stylesheet" href="../../../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -93,7 +93,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
--- a/doc/html/boost_optional/quick_start.html
+++ b/doc/html/boost_optional/quick_start.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>Quick Start</title>
 <link rel="stylesheet" href="../../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -155,7 +155,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
--- a/doc/html/boost_optional/quick_start/bypassing_unnecessary_default_construction.html
+++ b/doc/html/boost_optional/quick_start/bypassing_unnecessary_default_construction.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>Bypassing unnecessary default construction</title>
 <link rel="stylesheet" href="../../../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -61,7 +61,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
--- a/doc/html/boost_optional/quick_start/optional_automatic_variables.html
+++ b/doc/html/boost_optional/quick_start/optional_automatic_variables.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>Optional automatic variables</title>
 <link rel="stylesheet" href="../../../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -61,7 +61,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
--- a/doc/html/boost_optional/quick_start/optional_data_members.html
+++ b/doc/html/boost_optional/quick_start/optional_data_members.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>Optional data members</title>
 <link rel="stylesheet" href="../../../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -80,7 +80,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
--- a/doc/html/boost_optional/quick_start/storage_in_containers.html
+++ b/doc/html/boost_optional/quick_start/storage_in_containers.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>Storage in containers</title>
 <link rel="stylesheet" href="../../../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -50,7 +50,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
--- a/doc/html/boost_optional/reference/header__boost_optional_bad_optional_access_hpp_.html
+++ b/doc/html/boost_optional/reference/header__boost_optional_bad_optional_access_hpp_.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>Header &lt;boost/optional/bad_optional_access.hpp&gt;</title>
 <link rel="stylesheet" href="../../../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -49,7 +49,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
--- a/doc/html/boost_optional/reference/header__boost_optional_bad_optional_access_hpp_/detailed_semantics.html
+++ b/doc/html/boost_optional/reference/header__boost_optional_bad_optional_access_hpp_/detailed_semantics.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>Detailed semantics</title>
 <link rel="stylesheet" href="../../../../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -46,7 +46,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
--- a/doc/html/boost_optional/reference/header__boost_optional_hpp_.html
+++ b/doc/html/boost_optional/reference/header__boost_optional_hpp_.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>Header &lt;boost/optional.hpp&gt;</title>
 <link rel="stylesheet" href="../../../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -33,7 +33,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
--- a/doc/html/boost_optional/reference/header__boost_optional_optional_fwd_hpp_.html
+++ b/doc/html/boost_optional/reference/header__boost_optional_optional_fwd_hpp_.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>Header &lt;boost/optional/optional_fwd.hpp&gt;</title>
 <link rel="stylesheet" href="../../../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -52,7 +52,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
--- a/doc/html/boost_optional/reference/header__boost_optional_optional_hpp_/detailed_semantics___free_functions.html
+++ b/doc/html/boost_optional/reference/header__boost_optional_optional_hpp_/detailed_semantics___free_functions.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>Detailed Semantics - Free Functions</title>
 <link rel="stylesheet" href="../../../../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -507,7 +507,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
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--- a/doc/html/boost_optional/reference/header__boost_optional_optional_hpp_/detailed_semantics___optional_references.html
+++ b/doc/html/boost_optional/reference/header__boost_optional_optional_hpp_/detailed_semantics___optional_references.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>Detailed Semantics - Optional References</title>
 <link rel="stylesheet" href="../../../../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -538,7 +538,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
--- a/doc/html/boost_optional/reference/header__boost_optional_optional_hpp_/detailed_semantics___optional_values.html
+++ b/doc/html/boost_optional/reference/header__boost_optional_optional_hpp_/detailed_semantics___optional_values.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>Detailed Semantics - Optional Values</title>
 <link rel="stylesheet" href="../../../../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -1774,7 +1774,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
--- a/doc/html/boost_optional/reference/header__boost_optional_optional_hpp_/header_optional_in_place_init.html
+++ b/doc/html/boost_optional/reference/header__boost_optional_optional_hpp_/header_optional_in_place_init.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>Initialization tags</title>
 <link rel="stylesheet" href="../../../../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -47,7 +47,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
--- a/doc/html/boost_optional/reference/header__boost_optional_optional_hpp_/header_optional_optional_refs.html
+++ b/doc/html/boost_optional/reference/header__boost_optional_optional_hpp_/header_optional_optional_refs.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>Optional References</title>
 <link rel="stylesheet" href="../../../../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -104,7 +104,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
--- a/doc/html/boost_optional/reference/header__boost_optional_optional_hpp_/header_optional_optional_values.html
+++ b/doc/html/boost_optional/reference/header__boost_optional_optional_hpp_/header_optional_optional_values.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>Optional Values</title>
 <link rel="stylesheet" href="../../../../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -139,7 +139,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
--- a/doc/html/boost_optional/reference/io_header.html
+++ b/doc/html/boost_optional/reference/io_header.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>Header &lt;boost/optional/optional_io.hpp&gt;</title>
 <link rel="stylesheet" href="../../../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -58,7 +58,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
--- a/doc/html/boost_optional/reference/io_header/io_semantics.html
+++ b/doc/html/boost_optional/reference/io_header/io_semantics.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>Detailed semantics</title>
 <link rel="stylesheet" href="../../../../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -32,7 +32,7 @@
          <span class="special">&lt;</span><span class="keyword">class</span>
          <span class="identifier">CharType</span><span class="special">,</span>
          <span class="keyword">class</span> <span class="identifier">CharTrait</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span></code>
-          <br> &#160;&#160;&#160;&#160;<code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">basic_ostream</span><span class="special">&lt;</span><span class="identifier">CharType</span><span class="special">,</span> <span class="identifier">CharTrait</span><span class="special">&gt;&amp;</span></code> <br> &#160;&#160;&#160;&#160;<code class="computeroutput"><span class="keyword">operator</span><span class="special">&lt;&lt;(</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">basic_ostream</span><span class="special">&lt;</span><span class="identifier">CharType</span><span class="special">,</span> <span class="identifier">CharTrait</span><span class="special">&gt;&amp;</span>
+          <br>     <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">basic_ostream</span><span class="special">&lt;</span><span class="identifier">CharType</span><span class="special">,</span> <span class="identifier">CharTrait</span><span class="special">&gt;&amp;</span></code> <br>     <code class="computeroutput"><span class="keyword">operator</span><span class="special">&lt;&lt;(</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">basic_ostream</span><span class="special">&lt;</span><span class="identifier">CharType</span><span class="special">,</span> <span class="identifier">CharTrait</span><span class="special">&gt;&amp;</span>
          <span class="identifier">out</span><span class="special">,</span>
          <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">v</span><span class="special">);</span></code>
        </p>
@ -53,8 +53,8 @@
        </p>
 <p>
          <code class="computeroutput"><span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">CharType</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">CharTrait</span><span class="special">,</span>
-          <span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span></code> <br> &#160;&#160;&#160;&#160;<code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">basic_ostream</span><span class="special">&lt;</span><span class="identifier">CharType</span><span class="special">,</span> <span class="identifier">CharTrait</span><span class="special">&gt;&amp;</span></code>
-          <br> &#160;&#160;&#160;&#160;<code class="computeroutput"><span class="keyword">operator</span><span class="special">&lt;&lt;(</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">basic_ostream</span><span class="special">&lt;</span><span class="identifier">CharType</span><span class="special">,</span> <span class="identifier">CharTrait</span><span class="special">&gt;&amp;</span> <span class="identifier">out</span><span class="special">,</span> <span class="identifier">none_t</span><span class="special">);</span></code>
+          <span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span></code> <br>     <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">basic_ostream</span><span class="special">&lt;</span><span class="identifier">CharType</span><span class="special">,</span> <span class="identifier">CharTrait</span><span class="special">&gt;&amp;</span></code>
+          <br>     <code class="computeroutput"><span class="keyword">operator</span><span class="special">&lt;&lt;(</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">basic_ostream</span><span class="special">&lt;</span><span class="identifier">CharType</span><span class="special">,</span> <span class="identifier">CharTrait</span><span class="special">&gt;&amp;</span> <span class="identifier">out</span><span class="special">,</span> <span class="identifier">none_t</span><span class="special">);</span></code>
        </p>
 <div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
 <li class="listitem">
@ -70,8 +70,8 @@
        </p>
 <p>
          <code class="computeroutput"><span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">CharType</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">CharTrait</span><span class="special">,</span>
-          <span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span></code> <br> &#160;&#160;&#160;&#160;<code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">basic_ostream</span><span class="special">&lt;</span><span class="identifier">CharType</span><span class="special">,</span> <span class="identifier">CharTrait</span><span class="special">&gt;&amp;</span></code>
-          <br> &#160;&#160;&#160;&#160;<code class="computeroutput"><span class="keyword">operator</span><span class="special">&gt;&gt;(</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">basic_istream</span><span class="special">&lt;</span><span class="identifier">CharType</span><span class="special">,</span> <span class="identifier">CharTrait</span><span class="special">&gt;&amp;</span> <span class="identifier">in</span><span class="special">,</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;&amp;</span> <span class="identifier">v</span><span class="special">);</span></code>
+          <span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span></code> <br>     <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">basic_ostream</span><span class="special">&lt;</span><span class="identifier">CharType</span><span class="special">,</span> <span class="identifier">CharTrait</span><span class="special">&gt;&amp;</span></code>
+          <br>     <code class="computeroutput"><span class="keyword">operator</span><span class="special">&gt;&gt;(</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">basic_istream</span><span class="special">&lt;</span><span class="identifier">CharType</span><span class="special">,</span> <span class="identifier">CharTrait</span><span class="special">&gt;&amp;</span> <span class="identifier">in</span><span class="special">,</span> <span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;&amp;</span> <span class="identifier">v</span><span class="special">);</span></code>
        </p>
 <div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
 <li class="listitem">
@ -98,7 +98,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
--- a/doc/html/boost_optional/relnotes.html
+++ b/doc/html/boost_optional/relnotes.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>Release Notes</title>
 <link rel="stylesheet" href="../../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -28,6 +28,51 @@
 </h2></div></div></div>
 <h4>
 <a name="boost_optional.relnotes.h0"></a>
+      <span class="phrase"><a name="boost_optional.relnotes.boost_release_1_76"></a></span><a class="link" href="relnotes.html#boost_optional.relnotes.boost_release_1_76">Boost
+      Release 1.76</a>
+    </h4>
+<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
+          Fixed MSVC warning C4702.
+        </li></ul></div>
+<h4>
+<a name="boost_optional.relnotes.h1"></a>
+      <span class="phrase"><a name="boost_optional.relnotes.boost_release_1_75"></a></span><a class="link" href="relnotes.html#boost_optional.relnotes.boost_release_1_75">Boost
+      Release 1.75</a>
+    </h4>
+<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
+<li class="listitem">
+          <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">none</span></code> is <code class="computeroutput"><span class="keyword">constexpr</span></code>-declared.
+        </li>
+<li class="listitem">
+          Fixed <a href="https://github.com/boostorg/optional/issues/78" target="_top">issue
+          #78</a>.
+        </li>
+</ul></div>
+<h4>
+<a name="boost_optional.relnotes.h2"></a>
+      <span class="phrase"><a name="boost_optional.relnotes.boost_release_1_73"></a></span><a class="link" href="relnotes.html#boost_optional.relnotes.boost_release_1_73">Boost
+      Release 1.73</a>
+    </h4>
+<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
+<li class="listitem">
+          Fixed <a href="https://github.com/boostorg/optional/issues/78" target="_top">issue
+          #78</a>.
+        </li>
+<li class="listitem">
+          <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">none</span></code> is now declared as an inline variable
+          (on compilers that support it): there is only one instance of <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">none</span></code> across all translation units.
+        </li>
+<li class="listitem">
+          Fixed a number of compilation errors in GCC 4.4.7 in <code class="computeroutput"><span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span></code> for trivial <code class="computeroutput"><span class="identifier">T</span></code>s.
+          Thanks to Robert Leahy for the fix. For details see <a href="https://github.com/boostorg/optional/pull/80" target="_top">pr
+          #78</a>.
+        </li>
+<li class="listitem">
+          Now surpressing warning <code class="computeroutput"><span class="special">-</span><span class="identifier">Wweak</span><span class="special">-</span><span class="identifier">vtables</span></code>.
+        </li>
+</ul></div>
+<h4>
+<a name="boost_optional.relnotes.h3"></a>
      <span class="phrase"><a name="boost_optional.relnotes.boost_release_1_69"></a></span><a class="link" href="relnotes.html#boost_optional.relnotes.boost_release_1_69">Boost
      Release 1.69</a>
    </h4>
@ -45,7 +90,7 @@
        </li>
 </ul></div>
 <h4>
-<a name="boost_optional.relnotes.h1"></a>
+<a name="boost_optional.relnotes.h4"></a>
      <span class="phrase"><a name="boost_optional.relnotes.boost_release_1_68"></a></span><a class="link" href="relnotes.html#boost_optional.relnotes.boost_release_1_68">Boost
      Release 1.68</a>
    </h4>
@ -62,7 +107,7 @@
        </li>
 </ul></div>
 <h4>
-<a name="boost_optional.relnotes.h2"></a>
+<a name="boost_optional.relnotes.h5"></a>
      <span class="phrase"><a name="boost_optional.relnotes.boost_release_1_67"></a></span><a class="link" href="relnotes.html#boost_optional.relnotes.boost_release_1_67">Boost
      Release 1.67</a>
    </h4>
@ -76,7 +121,7 @@
        </li>
 </ul></div>
 <h4>
-<a name="boost_optional.relnotes.h3"></a>
+<a name="boost_optional.relnotes.h6"></a>
      <span class="phrase"><a name="boost_optional.relnotes.boost_release_1_66"></a></span><a class="link" href="relnotes.html#boost_optional.relnotes.boost_release_1_66">Boost
      Release 1.66</a>
    </h4>
@ -94,7 +139,7 @@
        </li>
 </ul></div>
 <h4>
-<a name="boost_optional.relnotes.h4"></a>
+<a name="boost_optional.relnotes.h7"></a>
      <span class="phrase"><a name="boost_optional.relnotes.boost_release_1_63"></a></span><a class="link" href="relnotes.html#boost_optional.relnotes.boost_release_1_63">Boost
      Release 1.63</a>
    </h4>
@ -118,7 +163,7 @@
        </li>
 </ul></div>
 <h4>
-<a name="boost_optional.relnotes.h5"></a>
+<a name="boost_optional.relnotes.h8"></a>
      <span class="phrase"><a name="boost_optional.relnotes.boost_release_1_62"></a></span><a class="link" href="relnotes.html#boost_optional.relnotes.boost_release_1_62">Boost
      Release 1.62</a>
    </h4>
@ -126,7 +171,7 @@
          Fixed <a href="https://svn.boost.org/trac/boost/ticket/12179" target="_top">Trac #12179</a>.
        </li></ul></div>
 <h4>
-<a name="boost_optional.relnotes.h6"></a>
+<a name="boost_optional.relnotes.h9"></a>
      <span class="phrase"><a name="boost_optional.relnotes.boost_release_1_61"></a></span><a class="link" href="relnotes.html#boost_optional.relnotes.boost_release_1_61">Boost
      Release 1.61</a>
    </h4>
@ -169,7 +214,7 @@
        </li>
 </ul></div>
 <h4>
-<a name="boost_optional.relnotes.h7"></a>
+<a name="boost_optional.relnotes.h10"></a>
      <span class="phrase"><a name="boost_optional.relnotes.boost_release_1_60"></a></span><a class="link" href="relnotes.html#boost_optional.relnotes.boost_release_1_60">Boost
      Release 1.60</a>
    </h4>
@ -180,7 +225,7 @@
          #11203</a>.
        </li></ul></div>
 <h4>
-<a name="boost_optional.relnotes.h8"></a>
+<a name="boost_optional.relnotes.h11"></a>
      <span class="phrase"><a name="boost_optional.relnotes.boost_release_1_59"></a></span><a class="link" href="relnotes.html#boost_optional.relnotes.boost_release_1_59">Boost
      Release 1.59</a>
    </h4>
@ -194,7 +239,7 @@
        </li>
 </ul></div>
 <h4>
-<a name="boost_optional.relnotes.h9"></a>
+<a name="boost_optional.relnotes.h12"></a>
      <span class="phrase"><a name="boost_optional.relnotes.boost_release_1_58"></a></span><a class="link" href="relnotes.html#boost_optional.relnotes.boost_release_1_58">Boost
      Release 1.58</a>
    </h4>
@ -230,7 +275,7 @@
        </li>
 </ul></div>
 <h4>
-<a name="boost_optional.relnotes.h10"></a>
+<a name="boost_optional.relnotes.h13"></a>
      <span class="phrase"><a name="boost_optional.relnotes.boost_release_1_57"></a></span><a class="link" href="relnotes.html#boost_optional.relnotes.boost_release_1_57">Boost
      Release 1.57</a>
    </h4>
@ -240,7 +285,7 @@
          to fix C++03 compile error on <code class="computeroutput"><span class="identifier">logic_error</span><span class="special">(</span><span class="string">"..."</span><span class="special">)</span></code>"</em></span>.
        </li></ul></div>
 <h4>
-<a name="boost_optional.relnotes.h11"></a>
+<a name="boost_optional.relnotes.h14"></a>
      <span class="phrase"><a name="boost_optional.relnotes.boost_release_1_56"></a></span><a class="link" href="relnotes.html#boost_optional.relnotes.boost_release_1_56">Boost
      Release 1.56</a>
    </h4>
@ -297,7 +342,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
--- a/doc/html/boost_optional/tutorial/design_overview.html
+++ b/doc/html/boost_optional/tutorial/design_overview.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>Design Overview</title>
 <link rel="stylesheet" href="../../../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -65,8 +65,8 @@
          <code class="computeroutput"><span class="identifier">npos</span></code>, -1, etc... This is
          equivalent to adding the special value to the set of possible values of
          a given type. This super set of <code class="computeroutput"><span class="identifier">T</span></code>
-          plus some <span class="emphasis"><em>nil_t</em></span>&#8212;where <code class="computeroutput"><span class="identifier">nil_t</span></code>
-          is some stateless POD&#8212;can be modeled in modern languages as a <span class="bold"><strong>discriminated union</strong></span> of T and nil_t. Discriminated
+          plus some <span class="emphasis"><em>nil_t</em></span>—where <code class="computeroutput"><span class="identifier">nil_t</span></code>
+          is some stateless POD—can be modeled in modern languages as a <span class="bold"><strong>discriminated union</strong></span> of T and nil_t. Discriminated
          unions are often called <span class="emphasis"><em>variants</em></span>. A variant has a
          <span class="emphasis"><em>current type</em></span>, which in our case is either <code class="computeroutput"><span class="identifier">T</span></code> or <code class="computeroutput"><span class="identifier">nil_t</span></code>.
          Using the <a href="../../../../../variant/index.html" target="_top">Boost.Variant</a>
@ -100,8 +100,8 @@
        </p>
 <p>
          In any event, both the discriminated-union or the single-element container
-          models serve as a conceptual ground for a class representing optional&#8212;i.e.
-          possibly uninitialized&#8212;objects. For instance, these models show the
+          models serve as a conceptual ground for a class representing optional—i.e.
+          possibly uninitialized—objects. For instance, these models show the
          <span class="emphasis"><em>exact</em></span> semantics required for a wrapper of optional
          values:
        </p>
@ -170,7 +170,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
--- a/doc/html/boost_optional/tutorial/design_overview/the_interface.html
+++ b/doc/html/boost_optional/tutorial/design_overview/the_interface.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>The Interface</title>
 <link rel="stylesheet" href="../../../../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -79,7 +79,7 @@
          facto</em></span> standard for handling optional objects because all you
          have to do to refer to a value which you don't really have is to use a
          null pointer value of the appropriate type. Pointers have been used for
-          decades&#8212;from the days of C APIs to modern C++ libraries&#8212;to <span class="emphasis"><em>refer</em></span>
+          decades—from the days of C APIs to modern C++ libraries—to <span class="emphasis"><em>refer</em></span>
          to optional (that is, possibly nonexistent) objects; particularly as optional
          arguments to a function, but also quite often as optional data members.
        </p>
@ -93,7 +93,7 @@
          and this information is tied to the <span class="emphasis"><em>syntax</em></span> of the
          expressions. That is, the presence of operators <code class="computeroutput"><span class="special">*</span></code>
          and <code class="computeroutput"><span class="special">-&gt;</span></code> tell by themselves
-          &#8212;without any additional context&#8212; that the expression will be undefined
+          —without any additional context— that the expression will be undefined
          unless the implied pointee actually exist.
        </p>
 <p>
@ -173,7 +173,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
--- a/doc/html/boost_optional/tutorial/design_overview/the_semantics.html
+++ b/doc/html/boost_optional/tutorial/design_overview/the_semantics.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>The semantics</title>
 <link rel="stylesheet" href="../../../../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -107,7 +107,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
--- a/doc/html/boost_optional/tutorial/exception_safety_guarantees.html
+++ b/doc/html/boost_optional/tutorial/exception_safety_guarantees.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>Exception Safety Guarantees</title>
 <link rel="stylesheet" href="../../../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -161,7 +161,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
--- a/doc/html/boost_optional/tutorial/gotchas.html
+++ b/doc/html/boost_optional/tutorial/gotchas.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>Gotchas</title>
 <link rel="stylesheet" href="../../../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -37,7 +37,7 @@
        </p>
 <p>
          First, it is functionally similar to a tristate boolean (false, maybe,
-          true) &#8212;such as <a href="../../../../../../doc/html/tribool.html" target="_top">boost::tribool</a>&#8212;
+          true) —such as <a href="../../../../../../doc/html/tribool.html" target="_top">boost::tribool</a>—
          except that in a tristate boolean, the maybe state <span class="underline">represents
          a valid value</span>, unlike the corresponding state of an uninitialized
          <code class="computeroutput"><span class="identifier">optional</span><span class="special">&lt;</span><span class="keyword">bool</span><span class="special">&gt;</span></code>.
@ -98,7 +98,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
--- a/doc/html/boost_optional/tutorial/gotchas/false_positive_with__wmaybe_uninitialized.html
+++ b/doc/html/boost_optional/tutorial/gotchas/false_positive_with__wmaybe_uninitialized.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>False positive with -Wmaybe-uninitialized</title>
 <link rel="stylesheet" href="../../../../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -63,7 +63,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
--- a/doc/html/boost_optional/tutorial/gotchas/mixed_relational_comparisons.html
+++ b/doc/html/boost_optional/tutorial/gotchas/mixed_relational_comparisons.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>Mixed relational comparisons</title>
 <link rel="stylesheet" href="../../../../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -45,7 +45,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
--- a/doc/html/boost_optional/tutorial/gotchas/moved_from__optional_.html
+++ b/doc/html/boost_optional/tutorial/gotchas/moved_from__optional_.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>Moved-from optional</title>
 <link rel="stylesheet" href="../../../../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -49,7 +49,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
--- a/doc/html/boost_optional/tutorial/in_place_factories.html
+++ b/doc/html/boost_optional/tutorial/in_place_factories.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>In-Place Factories</title>
 <link rel="stylesheet" href="../../../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -183,7 +183,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
--- a/doc/html/boost_optional/tutorial/io_operators.html
+++ b/doc/html/boost_optional/tutorial/io_operators.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>IO operators</title>
 <link rel="stylesheet" href="../../../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -73,7 +73,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
--- a/doc/html/boost_optional/tutorial/optional_references.html
+++ b/doc/html/boost_optional/tutorial/optional_references.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>Optional references</title>
 <link rel="stylesheet" href="../../../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -103,7 +103,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
--- a/doc/html/boost_optional/tutorial/optional_references/rebinding_semantics_for_assignment_of_optional_references.html
+++ b/doc/html/boost_optional/tutorial/optional_references/rebinding_semantics_for_assignment_of_optional_references.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>Rebinding semantics for assignment of optional references</title>
 <link rel="stylesheet" href="../../../../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -133,7 +133,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
--- a/doc/html/boost_optional/tutorial/performance_considerations.html
+++ b/doc/html/boost_optional/tutorial/performance_considerations.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>Performance considerations</title>
 <link rel="stylesheet" href="../../../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -251,7 +251,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
--- a/doc/html/boost_optional/tutorial/relational_operators.html
+++ b/doc/html/boost_optional/tutorial/relational_operators.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>Relational operators</title>
 <link rel="stylesheet" href="../../../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -99,7 +99,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
--- a/doc/html/boost_optional/tutorial/type_requirements.html
+++ b/doc/html/boost_optional/tutorial/type_requirements.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>Type requirements</title>
 <link rel="stylesheet" href="../../../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -95,7 +95,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
--- a/doc/html/boost_optional/tutorial/when_to_use_optional.html
+++ b/doc/html/boost_optional/tutorial/when_to_use_optional.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>When to use Optional</title>
 <link rel="stylesheet" href="../../../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -128,7 +128,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
--- a/doc/html/index.html
+++ b/doc/html/index.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>Boost.Optional</title>
 <link rel="stylesheet" href="../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -25,8 +25,8 @@
 <div><div class="author"><h3 class="author">
 <span class="firstname">Fernando Luis</span> <span class="surname">Cacciola Carballal</span>
 </h3></div></div>
-<div><p class="copyright">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal</p></div>
-<div><p class="copyright">Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski</p></div>
+<div><p class="copyright">Copyright © 2003-2007 Fernando Luis Cacciola Carballal</p></div>
+<div><p class="copyright">Copyright © 2014-2021 Andrzej Krzemieński</p></div>
 <div><div class="legalnotice">
 <a name="optional.legal"></a><p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
@ -145,7 +145,7 @@
 </div>
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
-<td align="left"><p><small>Last revised: November 08, 2018 at 17:44:53 GMT</small></p></td>
+<td align="left"><p><small>Last revised: March 10, 2021 at 22:06:01 GMT</small></p></td>
 <td align="right"><div class="copyright-footer"></div></td>
 </tr></table>
 <hr>
--- a/doc/html/optional/reference.html
+++ b/doc/html/optional/reference.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>Reference</title>
 <link rel="stylesheet" href="../../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -54,7 +54,7 @@

 <span class="keyword">class</span> <span class="identifier">none_t</span> <span class="special">{/*</span> <span class="identifier">see</span> <span class="identifier">below</span> <span class="special">*/};</span>

-<span class="keyword">const</span> <span class="identifier">none_t</span> <span class="identifier">none</span> <span class="special">(/*</span> <span class="identifier">see</span> <span class="identifier">below</span> <span class="special">*/);</span>
+<span class="keyword">inline</span> <span class="keyword">constexpr</span> <span class="identifier">none_t</span> <span class="identifier">none</span> <span class="special">(/*</span> <span class="identifier">see</span> <span class="identifier">below</span> <span class="special">*/);</span>

 <span class="special">}</span> <span class="comment">// namespace boost</span>
 </pre>
@ -75,7 +75,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
--- a/doc/html/optional/reference/header__boost_optional_optional_hpp_.html
+++ b/doc/html/optional/reference/header__boost_optional_optional_hpp_.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>Header &lt;boost/optional/optional.hpp&gt;</title>
 <link rel="stylesheet" href="../../../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -97,7 +97,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
--- a/doc/html/optional/tutorial.html
+++ b/doc/html/optional/tutorial.html
@ -1,6 +1,6 @@
 <html>
 <head>
-<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
+<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>Tutorial</title>
 <link rel="stylesheet" href="../../../../../doc/src/boostbook.css" type="text/css">
 <meta name="generator" content="DocBook XSL Stylesheets Vsnapshot">
@ -139,7 +139,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright &#169; 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright &#169; 2014-2018 Andrzej Krzemie&#324;ski<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
--- a/include/boost/none.hpp
+++ b/include/boost/none.hpp
@ -13,6 +13,7 @@
 #ifndef BOOST_NONE_17SEP2003_HPP
 #define BOOST_NONE_17SEP2003_HPP

+#include "boost/config.hpp"
 #include "boost/none_t.hpp"

 // NOTE: Borland users have to include this header outside any precompiled headers
@ -23,7 +24,7 @@ namespace boost {

 #ifdef BOOST_OPTIONAL_USE_OLD_DEFINITION_OF_NONE

-none_t const none = (static_cast<none_t>(0)) ;
+BOOST_INLINE_VARIABLE none_t BOOST_CONSTEXPR_OR_CONST none = (static_cast<none_t>(0)) ;

 #elif defined BOOST_OPTIONAL_USE_SINGLETON_DEFINITION_OF_NONE

@ -35,7 +36,7 @@ namespace detail { namespace optional_detail {
  {
    static const T instance;
  };
-  
+
  template <typename T>
  const T none_instance<T>::instance = T(); // global, but because 'tis a template, no cpp file required

@ -44,16 +45,15 @@ namespace detail { namespace optional_detail {

 namespace {
  // TU-local
-  const none_t& none = detail::optional_detail::none_instance<none_t>::instance; 
+  const none_t& none = detail::optional_detail::none_instance<none_t>::instance;
 }

 #else

-const none_t none ((none_t::init_tag()));
+BOOST_INLINE_VARIABLE BOOST_CONSTEXPR_OR_CONST none_t none ((none_t::init_tag()));

 #endif // older definitions

 } // namespace boost

 #endif // header guard
-
--- a/include/boost/none_t.hpp
+++ b/include/boost/none_t.hpp
@ -13,6 +13,8 @@
 #ifndef BOOST_NONE_T_17SEP2003_HPP
 #define BOOST_NONE_T_17SEP2003_HPP

+#include <boost/config.hpp>
+
 namespace boost {

 #ifdef BOOST_OPTIONAL_USE_OLD_DEFINITION_OF_NONE
@ -29,7 +31,7 @@ class none_t {};
 struct none_t
 {
  struct init_tag{};
-  explicit none_t(init_tag){} // to disable default constructor
+  explicit BOOST_CONSTEXPR none_t(init_tag){} // to disable default constructor
 };

 #endif // old implementation workarounds
--- a/include/boost/optional/bad_optional_access.hpp
+++ b/include/boost/optional/bad_optional_access.hpp
@ -19,6 +19,11 @@

 namespace boost {

+#if defined(__clang__)
+# pragma clang diagnostic push
+# pragma clang diagnostic ignored "-Wweak-vtables"
+#endif
+
 class bad_optional_access : public std::logic_error
 {
 public:
@ -27,6 +32,10 @@ public:
    {}
 };

+#if defined(__clang__)
+# pragma clang diagnostic pop
+#endif
+
 } // namespace boost

 #endif
--- a/include/boost/optional/detail/old_optional_implementation.hpp
+++ b/include/boost/optional/detail/old_optional_implementation.hpp
@ -79,7 +79,7 @@ class optional_base : public optional_tag
  private :

    typedef
-#if !BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x564))
+#if !BOOST_WORKAROUND(BOOST_BORLANDC, BOOST_TESTED_AT(0x564))
    BOOST_DEDUCED_TYPENAME
 #endif
    ::boost::detail::make_reference_content<T>::type internal_type ;
@ -619,7 +619,7 @@ class optional_base : public optional_tag
    reference_const_type dereference( internal_type const* p, is_reference_tag     ) const { return p->get() ; }
    reference_type       dereference( internal_type*       p, is_reference_tag     )       { return p->get() ; }

-#if BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x581))
+#if BOOST_WORKAROUND(BOOST_BORLANDC, BOOST_TESTED_AT(0x581))
    void destroy_impl ( is_not_reference_tag ) { get_ptr_impl()->internal_type::~internal_type() ; m_initialized = false ; }
 #else
    void destroy_impl ( is_not_reference_tag ) { get_ptr_impl()->~T() ; m_initialized = false ; }
--- a/include/boost/optional/detail/optional_config.hpp
+++ b/include/boost/optional/detail/optional_config.hpp
@ -28,7 +28,7 @@
 # define BOOST_OPTIONAL_NO_INPLACE_FACTORY_SUPPORT
 #endif

-#if BOOST_WORKAROUND(__BORLANDC__, <= 0x551)
+#if BOOST_WORKAROUND(BOOST_BORLANDC, <= 0x551)
 // BCB (5.5.1) cannot parse the nested template struct in an inplace factory.
 # define BOOST_OPTIONAL_NO_INPLACE_FACTORY_SUPPORT
 #endif
--- a/include/boost/optional/detail/optional_reference_spec.hpp
+++ b/include/boost/optional/detail/optional_reference_spec.hpp
@ -151,7 +151,14 @@ public:
    T* get_ptr() const BOOST_NOEXCEPT { return ptr_; }
    T* operator->() const { BOOST_ASSERT(ptr_); return ptr_; }
    T& operator*() const { BOOST_ASSERT(ptr_); return *ptr_; }
-    T& value() const { return ptr_ ? *ptr_ : (throw_exception(bad_optional_access()), *ptr_); }
+    
+    T& value() const
+    {
+      if (this->is_initialized())
+        return this->get();
+      else
+        throw_exception(bad_optional_access());
+    }
    
    bool operator!() const BOOST_NOEXCEPT { return ptr_ == 0; }  
    BOOST_EXPLICIT_OPERATOR_BOOL_NOEXCEPT()
--- a/include/boost/optional/detail/optional_trivially_copyable_base.hpp
+++ b/include/boost/optional/detail/optional_trivially_copyable_base.hpp
@ -359,7 +359,7 @@ class tc_optional_base : public optional_tag
    template<class Expr>
    void construct ( Expr const& factory, in_place_factory_base const* )
     {
-       boost_optional_detail::construct<value_type>(factory, m_storage.address());
+       boost_optional_detail::construct<value_type>(factory, boost::addressof(m_storage));
       m_initialized = true ;
     }

--- a/include/boost/optional/optional.hpp
+++ b/include/boost/optional/optional.hpp
@ -777,7 +777,7 @@ class optional_base : public optional_tag

 #include <boost/optional/detail/optional_trivially_copyable_base.hpp>

-// definition of metafunciton is_optional_val_init_candidate
+// definition of metafunction is_optional_val_init_candidate
 template <typename U>
 struct is_optional_related
  : boost::conditional< boost::is_base_of<optional_detail::optional_tag, BOOST_DEDUCED_TYPENAME boost::decay<U>::type>::value
@ -813,9 +813,14 @@ struct is_optional_constructible : boost::true_type

 #endif // is_convertible condition

-template <typename T, typename U>
+template <typename T, typename U, bool = is_optional_related<U>::value>
 struct is_optional_val_init_candidate
-  : boost::conditional< !is_optional_related<U>::value && is_convertible_to_T_or_factory<T, U>::value
+  : boost::false_type
+{};
+
+template <typename T, typename U>
+struct is_optional_val_init_candidate<T, U, false>
+  : boost::conditional< is_convertible_to_T_or_factory<T, U>::value
                      , boost::true_type, boost::false_type>::type
 {};

@ -967,7 +972,7 @@ class optional
    // Can throw if T::T(T&&) does

 #ifndef BOOST_OPTIONAL_DETAIL_NO_DEFAULTED_MOVE_FUNCTIONS
-    optional ( optional && rhs ) = default;
+    optional ( optional && ) = default;
 #else
    optional ( optional && rhs )
      BOOST_NOEXCEPT_IF(::boost::is_nothrow_move_constructible<T>::value)
--- a/meta/libraries.json
+++ b/meta/libraries.json
@ -12,5 +12,6 @@
    "maintainers": [
        "Fernando Cacciola <fernando_cacciola -at- ciudad.com.ar>",
        "Andrzej Krzemienski <akrzemi1 -at- gmail.com>"
-    ]
+    ],
+    "cxxstd": "03"
 }
--- a/test/Jamfile.v2
+++ b/test/Jamfile.v2
@ -50,6 +50,7 @@ import testing ;
    [ run optional_test_member_T.cpp ]
    [ run optional_test_tc_base.cpp ]
    [ compile optional_test_sfinae_friendly_ctor.cpp ]
+    [ compile optional_test_path_assignment.cpp ]
    [ compile-fail optional_test_fail_const_swap.cpp ]
    [ compile-fail optional_test_ref_convert_assign_const_int_prevented.cpp ]
    [ compile-fail optional_test_fail1.cpp ]
--- a/test/optional_ref_assign_test_defs.hpp
+++ b/test/optional_ref_assign_test_defs.hpp
@ -13,7 +13,7 @@

 #include "boost/optional/optional.hpp"

-#ifdef __BORLANDC__
+#ifdef BOOST_BORLANDC
 #pragma hdrstop
 #endif

--- a/test/optional_test.cpp
+++ b/test/optional_test.cpp
@ -24,7 +24,7 @@

 #include "boost/optional/optional.hpp"

-#ifdef __BORLANDC__
+#ifdef BOOST_BORLANDC
 #pragma hdrstop
 #endif

--- a/test/optional_test_constructible_from_other.cpp
+++ b/test/optional_test_constructible_from_other.cpp
@ -26,12 +26,14 @@ struct size_tag {};
 template< typename T, typename U >
 struct is_constructible
 {
-    template< typename T1, typename U1 >
-    static yes_type check_helper(size_tag< sizeof(static_cast< T1 >(U1())) >*);
-    template< typename T1, typename U1 >
+    static U& get();
+
+    template< typename T1 >
+    static yes_type check_helper(size_tag< sizeof(static_cast< T1 >(get())) >*);
+    template< typename T1 >
    static no_type check_helper(...);

-    static const bool value = sizeof(check_helper< T, U >(0)) == sizeof(yes_type);
+    static const bool value = sizeof(check_helper< T >(0)) == sizeof(yes_type);
 };

 template< typename T >
--- a/test/optional_test_conversions_from_U.cpp
+++ b/test/optional_test_conversions_from_U.cpp
@ -11,7 +11,7 @@

 #include "boost/optional/optional.hpp"

-#ifdef __BORLANDC__
+#ifdef BOOST_BORLANDC
 #pragma hdrstop
 #endif

--- a/test/optional_test_convert_from_T.cpp
+++ b/test/optional_test_convert_from_T.cpp
@ -11,7 +11,7 @@

 #include "boost/optional/optional.hpp"

-#ifdef __BORLANDC__
+#ifdef BOOST_BORLANDC
 #pragma hdrstop
 #endif

--- a/test/optional_test_deleted_default_ctor.cpp
+++ b/test/optional_test_deleted_default_ctor.cpp
@ -1,5 +1,5 @@
 // Copyright 2017 Peter Dimov
-// Copyright 2017 Vinnie NotDefaultConstructible
+// Copyright 2017 Vinnie Falco
 // Copyright 2018 Andrzej Krzemienski
 //
 // Distributed under the Boost Software License, Version 1.0.
--- a/test/optional_test_emplace.cpp
+++ b/test/optional_test_emplace.cpp
@ -11,10 +11,11 @@

 #include "boost/optional/optional.hpp"

-#ifdef __BORLANDC__
+#ifdef BOOST_BORLANDC
 #pragma hdrstop
 #endif

+#include <string>
 #include "boost/core/lightweight_test.hpp"
 #include "boost/none.hpp"

--- a/test/optional_test_empty_braces.cpp
+++ b/test/optional_test_empty_braces.cpp
@ -11,7 +11,7 @@

 #include "boost/optional/optional.hpp"

-#ifdef __BORLANDC__
+#ifdef BOOST_BORLANDC
 #pragma hdrstop
 #endif

--- a/test/optional_test_equals_none.cpp
+++ b/test/optional_test_equals_none.cpp
@ -11,7 +11,7 @@

 #include "boost/optional/optional.hpp"

-#ifdef __BORLANDC__
+#ifdef BOOST_BORLANDC
 #pragma hdrstop
 #endif

--- a/test/optional_test_experimental_traits.cpp
+++ b/test/optional_test_experimental_traits.cpp
@ -11,7 +11,7 @@

 #include "boost/optional/optional.hpp"

-#ifdef __BORLANDC__
+#ifdef BOOST_BORLANDC
 #pragma hdrstop
 #endif

--- a/test/optional_test_flat_map.cpp
+++ b/test/optional_test_flat_map.cpp
@ -11,7 +11,7 @@

 #include "boost/optional/optional.hpp"

-#ifdef __BORLANDC__
+#ifdef BOOST_BORLANDC
 #pragma hdrstop
 #endif

--- a/test/optional_test_inplace_factory.cpp
+++ b/test/optional_test_inplace_factory.cpp
@ -13,7 +13,7 @@
 #include<string>
 #include "boost/optional/optional.hpp"

-#ifdef __BORLANDC__
+#ifdef BOOST_BORLANDC
 #pragma hdrstop
 #endif

@ -31,10 +31,10 @@ struct Guard
  std::string str;
  Guard() : num() {}
  Guard(double num_, std::string str_) : num(num_), str(str_) {}
-  
+
  friend bool operator==(const Guard& lhs, const Guard& rhs) { return lhs.num == rhs.num && lhs.str == rhs.str; }
  friend bool operator!=(const Guard& lhs, const Guard& rhs) { return !(lhs == rhs); }
-  
+
 private:
  Guard(const Guard&);
  Guard& operator=(const Guard&);
@ -44,26 +44,30 @@ void test_ctor()
 {
 #ifndef BOOST_OPTIONAL_NO_INPLACE_FACTORY_SUPPORT
  Guard g0, g1(1.0, "one"), g2(2.0, "two");
-  
+
  boost::optional<Guard> og0 ( boost::in_place() );
  boost::optional<Guard> og1 ( boost::in_place(1.0, "one") );
  boost::optional<Guard> og1_( boost::in_place(1.0, "one") );
  boost::optional<Guard> og2 ( boost::in_place<Guard>(2.0, "two") );
-  
+
  BOOST_TEST(og0);
  BOOST_TEST(og1);
  BOOST_TEST(og1_);
  BOOST_TEST(og2);
-  
+
  BOOST_TEST(*og0  == g0);
  BOOST_TEST(*og1  == g1);
  BOOST_TEST(*og1_ == g1);
  BOOST_TEST(*og2  == g2);
-  
+
  BOOST_TEST(og1_ == og1);
  BOOST_TEST(og1_ != og2);
  BOOST_TEST(og1_ != og0);
-#endif 
+
+  boost::optional<unsigned int> o( boost::in_place(5) );
+  BOOST_TEST(o);
+  BOOST_TEST(*o == 5);
+#endif
 }

 void test_assign()
@ -71,27 +75,32 @@ void test_assign()
 #ifndef BOOST_OPTIONAL_NO_INPLACE_FACTORY_SUPPORT
 #ifndef BOOST_OPTIONAL_WEAK_OVERLOAD_RESOLUTION
  Guard g0, g1(1.0, "one"), g2(2.0, "two");
-  
+
  boost::optional<Guard> og0, og1, og1_, og2;
-  
+
  og0  = boost::in_place();
  og1  = boost::in_place(1.0, "one");
  og1_ = boost::in_place(1.0, "one");
  og2  = boost::in_place<Guard>(2.0, "two");
-  
+
  BOOST_TEST(og0);
  BOOST_TEST(og1);
  BOOST_TEST(og1_);
  BOOST_TEST(og2);
-  
+
  BOOST_TEST(*og0  == g0);
  BOOST_TEST(*og1  == g1);
  BOOST_TEST(*og1_ == g1);
  BOOST_TEST(*og2  == g2);
-  
+
  BOOST_TEST(og1_ == og1);
  BOOST_TEST(og1_ != og2);
  BOOST_TEST(og1_ != og0);
+
+  boost::optional<unsigned int> o;
+  o = boost::in_place(5);
+  BOOST_TEST(o);
+  BOOST_TEST(*o == 5);
 #endif
 #endif
 }
@ -101,4 +110,4 @@ int main()
  test_ctor();
  test_assign();
  return boost::report_errors();
-}
+}
--- a/test/optional_test_inplace_fail.cpp
+++ b/test/optional_test_inplace_fail.cpp
@ -13,7 +13,7 @@
 #include<string>
 #include "boost/optional/optional.hpp"

-#ifdef __BORLANDC__
+#ifdef BOOST_BORLANDC
 #pragma hdrstop
 #endif

--- a/test/optional_test_inplace_fail2.cpp
+++ b/test/optional_test_inplace_fail2.cpp
@ -13,7 +13,7 @@
 #include<string>
 #include "boost/optional/optional.hpp"

-#ifdef __BORLANDC__
+#ifdef BOOST_BORLANDC
 #pragma hdrstop
 #endif

--- a/test/optional_test_io.cpp
+++ b/test/optional_test_io.cpp
@ -14,7 +14,7 @@
 #include "boost/optional/optional.hpp"
 #include "boost/optional/optional_io.hpp"

-#ifdef __BORLANDC__
+#ifdef BOOST_BORLANDC
 #pragma hdrstop
 #endif

--- a/test/optional_test_make_optional.cpp
+++ b/test/optional_test_make_optional.cpp
@ -11,7 +11,7 @@

 #include "boost/optional/optional.hpp"

-#ifdef __BORLANDC__
+#ifdef BOOST_BORLANDC
 #pragma hdrstop
 #endif

--- a/test/optional_test_map.cpp
+++ b/test/optional_test_map.cpp
@ -11,7 +11,7 @@

 #include "boost/optional/optional.hpp"

-#ifdef __BORLANDC__
+#ifdef BOOST_BORLANDC
 #pragma hdrstop
 #endif

--- a/test/optional_test_maybe_uninitialized_warning.cpp
+++ b/test/optional_test_maybe_uninitialized_warning.cpp
@ -11,7 +11,7 @@

 #include "boost/optional/optional.hpp"

-#ifdef __BORLANDC__
+#ifdef BOOST_BORLANDC
 #pragma hdrstop
 #endif

--- a/test/optional_test_member_T.cpp
+++ b/test/optional_test_member_T.cpp
@ -11,7 +11,7 @@

 #include "boost/optional/optional.hpp"

-#ifdef __BORLANDC__
+#ifdef BOOST_BORLANDC
 #pragma hdrstop
 #endif

--- a/test/optional_test_minimum_requirements.cpp
+++ b/test/optional_test_minimum_requirements.cpp
@ -11,10 +11,11 @@

 #include "boost/optional/optional.hpp"

-#ifdef __BORLANDC__
+#ifdef BOOST_BORLANDC
 #pragma hdrstop
 #endif

+#include <string>
 #include "boost/core/lightweight_test.hpp"
 #include "boost/none.hpp"

--- a/test/optional_test_move.cpp
+++ b/test/optional_test_move.cpp
@ -12,7 +12,7 @@

 #include "boost/optional/optional.hpp"

-#ifdef __BORLANDC__
+#ifdef BOOST_BORLANDC
 #pragma hdrstop
 #endif

--- a/test/optional_test_msvc_bug_workaround.cpp
+++ b/test/optional_test_msvc_bug_workaround.cpp
@ -12,7 +12,7 @@
 #define BOOST_OPTIONAL_CONFIG_NO_RVALUE_REFERENCES
 #include "boost/optional/optional.hpp"

-#ifdef __BORLANDC__
+#ifdef BOOST_BORLANDC
 #pragma hdrstop
 #endif

--- a/test/optional_test_noexcept_move.cpp
+++ b/test/optional_test_noexcept_move.cpp
@ -12,7 +12,7 @@
 #include "boost/static_assert.hpp"
 #include "boost/optional/optional.hpp"

-#ifdef __BORLANDC__
+#ifdef BOOST_BORLANDC
 #pragma hdrstop
 #endif

--- a/test/optional_test_old_impl.cpp
+++ b/test/optional_test_old_impl.cpp
@ -12,7 +12,7 @@
 #define BOOST_OPTIONAL_CONFIG_USE_OLD_IMPLEMENTATION_OF_OPTIONAL // does old implementation still work for basic usage?
 #include "boost/optional/optional.hpp"

-#ifdef __BORLANDC__
+#ifdef BOOST_BORLANDC
 #pragma hdrstop
 #endif

--- a/test/optional_test_path_assignment.cpp
+++ b/test/optional_test_path_assignment.cpp
@ -0,0 +1,73 @@
+// Copyright (C) 2019 Andrzej Krzemienski.
+//
+// Use, modification, and distribution is subject to 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)
+//
+// See http://www.boost.org/lib/optional for documentation.
+//
+// You are welcome to contact the author at:
+//  akrzemi1@gmail.com
+
+#include "boost/optional/optional.hpp"
+
+#ifdef BOOST_BORLANDC
+#pragma hdrstop
+#endif
+
+#ifndef BOOST_OPTIONAL_DETAIL_NO_IS_CONSTRUCTIBLE_TRAIT
+#ifndef BOOST_OPTIONAL_DETAIL_NO_SFINAE_FRIENDLY_CONSTRUCTORS
+template <typename, typename>
+struct void_t
+{
+  typedef void type;
+};
+
+
+template <typename T, typename = void>
+struct trait
+{
+};
+
+// the following trait emulates properties std::iterator_traits
+template <typename T>
+struct trait<T, BOOST_DEDUCED_TYPENAME void_t<BOOST_DEDUCED_TYPENAME T::value_type,
+                                              BOOST_DEDUCED_TYPENAME boost::enable_if<boost::is_constructible<T, T&> >::type
+                                             >::type>
+{
+  typedef BOOST_DEDUCED_TYPENAME T::value_type value_type;
+};
+
+// This class emulates the properties of std::filesystem::path
+struct Path
+{
+
+#if __cplusplus >= 201103
+    template <typename T, typename = BOOST_DEDUCED_TYPENAME trait<T>::value_type>
+        Path(T const&);
+#else
+  template <typename T>
+    Path(T const&, BOOST_DEDUCED_TYPENAME trait<T>::value_type* = 0);
+#endif
+
+};
+#endif
+#endif
+
+
+int main()
+{
+#ifndef BOOST_OPTIONAL_DETAIL_NO_IS_CONSTRUCTIBLE_TRAIT
+#ifndef BOOST_OPTIONAL_DETAIL_NO_SFINAE_FRIENDLY_CONSTRUCTORS
+
+    boost::optional<Path> optFs1;
+    boost::optional<Path> optFs2;
+
+    optFs1 = optFs2;
+
+    // the following still fails although it shouldn't
+    //BOOST_STATIC_ASSERT((std::is_copy_constructible<boost::optional<Path>>::value));
+
+#endif
+#endif
+}
--- a/test/optional_test_ref_assign_const_int.cpp
+++ b/test/optional_test_ref_assign_const_int.cpp
@ -11,7 +11,7 @@

 #include "boost/optional/optional.hpp"

-#ifdef __BORLANDC__
+#ifdef BOOST_BORLANDC
 #pragma hdrstop
 #endif

--- a/test/optional_test_ref_assign_mutable_int.cpp
+++ b/test/optional_test_ref_assign_mutable_int.cpp
@ -11,7 +11,7 @@

 #include "boost/optional/optional.hpp"

-#ifdef __BORLANDC__
+#ifdef BOOST_BORLANDC
 #pragma hdrstop
 #endif

--- a/test/optional_test_ref_assign_portable_minimum.cpp
+++ b/test/optional_test_ref_assign_portable_minimum.cpp
@ -11,7 +11,7 @@

 #include "boost/optional/optional.hpp"

-#ifdef __BORLANDC__
+#ifdef BOOST_BORLANDC
 #pragma hdrstop
 #endif

--- a/test/optional_test_ref_convert_assign_const_int.cpp
+++ b/test/optional_test_ref_convert_assign_const_int.cpp
@ -11,7 +11,7 @@

 #include "boost/optional/optional.hpp"

-#ifdef __BORLANDC__
+#ifdef BOOST_BORLANDC
 #pragma hdrstop
 #endif

--- a/test/optional_test_ref_convert_assign_const_int_prevented.cpp
+++ b/test/optional_test_ref_convert_assign_const_int_prevented.cpp
@ -11,7 +11,7 @@

 #include "boost/optional/optional.hpp"

-#ifdef __BORLANDC__
+#ifdef BOOST_BORLANDC
 #pragma hdrstop
 #endif

--- a/test/optional_test_ref_convert_assign_mutable_int.cpp
+++ b/test/optional_test_ref_convert_assign_mutable_int.cpp
@ -11,7 +11,7 @@

 #include "boost/optional/optional.hpp"

-#ifdef __BORLANDC__
+#ifdef BOOST_BORLANDC
 #pragma hdrstop
 #endif

--- a/test/optional_test_ref_convert_assign_non_int.cpp
+++ b/test/optional_test_ref_convert_assign_non_int.cpp
@ -11,7 +11,7 @@

 #include "boost/optional/optional.hpp"

-#ifdef __BORLANDC__
+#ifdef BOOST_BORLANDC
 #pragma hdrstop
 #endif

--- a/test/optional_test_ref_converting_ctor.cpp
+++ b/test/optional_test_ref_converting_ctor.cpp
@ -11,7 +11,7 @@

 #include "boost/optional/optional.hpp"

-#ifdef __BORLANDC__
+#ifdef BOOST_BORLANDC
 #pragma hdrstop
 #endif

@ -93,7 +93,9 @@ template <typename T>
 void test_all_const_cases()
 {
  test_converting_ctor<T>();
+#ifndef BOOST_OPTIONAL_CONFIG_NO_PROPER_CONVERT_FROM_CONST_INT
  test_converting_ctor<const T>();
+#endif
  test_converting_ctor_for_noconst_const<T>();
 }

--- a/test/optional_test_ref_move.cpp
+++ b/test/optional_test_ref_move.cpp
@ -11,7 +11,7 @@

 #include "boost/optional/optional.hpp"

-#ifdef __BORLANDC__
+#ifdef BOOST_BORLANDC
 #pragma hdrstop
 #endif

--- a/test/optional_test_ref_portable_minimum.cpp
+++ b/test/optional_test_ref_portable_minimum.cpp
@ -11,7 +11,7 @@

 #include "boost/optional/optional.hpp"

-#ifdef __BORLANDC__
+#ifdef BOOST_BORLANDC
 #pragma hdrstop
 #endif

--- a/test/optional_test_ref_to_val.cpp
+++ b/test/optional_test_ref_to_val.cpp
@ -12,7 +12,7 @@

 #include "boost/optional/optional.hpp"

-#ifdef __BORLANDC__
+#ifdef BOOST_BORLANDC
 #pragma hdrstop
 #endif

--- a/test/optional_test_sfinae_friendly_ctor.cpp
+++ b/test/optional_test_sfinae_friendly_ctor.cpp
@ -11,7 +11,7 @@

 #include "boost/optional/optional.hpp"

-#ifdef __BORLANDC__
+#ifdef BOOST_BORLANDC
 #pragma hdrstop
 #endif

--- a/test/optional_test_static_properties.cpp
+++ b/test/optional_test_static_properties.cpp
@ -11,7 +11,7 @@

 #include "boost/optional/optional.hpp"

-#ifdef __BORLANDC__
+#ifdef BOOST_BORLANDC
 #pragma hdrstop
 #endif

--- a/test/optional_test_swap.cpp
+++ b/test/optional_test_swap.cpp
@ -17,7 +17,7 @@
 #include "boost/optional/optional.hpp"
 #include "boost/utility/in_place_factory.hpp"

-#ifdef __BORLANDC__
+#ifdef BOOST_BORLANDC
 #pragma hdrstop
 #endif

--- a/test/optional_test_tc_base.cpp
+++ b/test/optional_test_tc_base.cpp
@ -11,7 +11,7 @@

 #include "boost/optional/optional.hpp"

-#ifdef __BORLANDC__
+#ifdef BOOST_BORLANDC
 #pragma hdrstop
 #endif

--- a/Show More
+++ b/Show More
Author	SHA1	Message	Date
Andrzej Krzemienski	5a444eb84b	docs: updated copyright notice	2021-03-10 23:07:18 +01:00
Andrzej Krzemienski	0566bde447	Merge branch 'develop'	2021-03-10 23:01:22 +01:00
Andrzej Krzemieński	a70c51eed1	Merge pull request #91 from sdarwin/githubactions GitHub Actions config	2021-03-03 16:13:06 +01:00
sdarwin	9c9ff5e376	Add GitHub Actions config [ci skip]	2021-03-03 14:56:21 +00:00
Andrzej Krzemieński	708db7fe9a	Merge pull request #88 from sdarwin/drone Drone config	2021-01-21 21:18:22 +01:00
sdarwin	27971d8b11	add drone config [ci skip]	2021-01-21 19:42:29 +00:00
Andrzej Krzemieński	97da91f665	Merge pull request #89 from eldiener/develop [skip ci] Add "cxxstd" json field	2021-01-21 19:50:03 +01:00
Edward Diener	4a1a9c9cdd	[skip ci] Add "cxxstd" json field. The "cxxstd" json field is being added to each Boost library's meta json information for libraries in order to specify the minumum C++ standard compilation level. The value of this field matches one of the values for 'cxxstd' in Boost.Build. The purpose of doing this is to provide information for the Boost website documentation for each library which will specify the minimum C++ standard compilation that an end-user must employ in order to use the particular library. This will aid end-users who want to know if they can successfully use a Boost library based on their C++ compiler's compilation level, without having to search the library's documentation to find this out.	2021-01-20 23:02:52 -05:00
Andrzej Krzemienski	71feb7961b	Merge branch 'gieseanw-patch-1' into develop	2020-12-19 00:00:58 +01:00
gieseanw	ead529af54	Address unreachable code warning In MSVC optional<T&>::value() emits a warning C4702: unreachable code because throw_exception is marked BOOST_RETURN. Otherwise the ternary code might have been preferable. This change addresses the warning while preserving the functionality. It replicates optional<T>::value() for consistency.	2020-12-19 00:00:18 +01:00
Andrzej Krzemienski	45321f321e	polished release notes	2020-10-28 22:29:13 +01:00
Andrzej Krzemienski	18222c8394	Merge branch 'develop'	2020-10-28 21:36:29 +01:00
Andrzej Krzemienski	a7f49cbec8	Merge branch 'citrusmoose-make_none_t_literal_type' into develop	2020-10-24 17:18:22 +02:00
Andrzej Krzemienski	7e0b8145b5	boost::none is constexpr-declared	2020-10-24 17:17:10 +02:00
Andrzej Krzemienski	2b08711ec6	Merge branch 'make_none_t_literal_type' of https://github.com/citrusmoose/optional into citrusmoose-make_none_t_literal_type	2020-10-24 17:05:51 +02:00
Andrzej Krzemieński	88e7d55bbc	Merge pull request #85 from giomasce-throwaway/develop Fix funny mistake in copyright headers.	2020-10-09 16:28:33 +02:00
Giovanni Mascellani	9de55e6ffd	Fix funny mistake in copyright headers.	2020-10-09 15:35:58 +02:00
Andrzej Krzemieński	409a225afe	Merge pull request #84 from mbs-c/develop Add explicit <string> include to make tests compile with MSVC	2020-08-11 16:11:59 +02:00
Moritz Baumann	db5e156ebc	Add explicit <string> include to make tests compile with MSVC	2020-08-11 10:36:12 +02:00
Andrzej Krzemienski	aeac95857e	Merge branch 'eldiener-develop' into develop	2020-05-07 18:06:07 +02:00
Edward Diener	d5b7791710	Merge branch 'develop' of https://github.com/eldiener/optional into cppbuilder	2020-04-17 05:55:24 -04:00
Andrzej Krzemienski	c486bb724c	Merge branch 'develop'	2020-04-09 01:16:14 +02:00
Andrzej Krzemienski	19b94c01f3	added release notes	2020-04-09 01:12:22 +02:00
Andrzej Krzemienski	404f40bcc1	Merge branch 'RobertLeahy-develop' into develop	2020-04-06 00:43:05 +02:00
Andrzej Krzemienski	9b1f8033eb	Merge branch 'develop' of https://github.com/RobertLeahy/optional-2 into RobertLeahy-develop	2020-04-06 00:42:05 +02:00
Andrzej Krzemienski	e52d7d4a9e	Merge branch 'Kojoley-suppress-weak-vtables-warning' into develop	2020-04-05 23:47:19 +02:00
Andrzej Krzemienski	ed9edd54e4	Merge branch 'suppress-weak-vtables-warning' of https://github.com/Kojoley/optional into Kojoley-suppress-weak-vtables-warning	2020-04-05 23:30:40 +02:00
Andrzej Krzemienski	d2479d6f52	Merge branch 'develop'	2020-04-05 22:58:03 +02:00
Edward Diener	78d6563bce	Change __BORLANDC__ to BOOST_BORLANDC, which is defined in Boost config for the Embarcadero non-clang-based compilers.	2020-03-30 14:04:35 -04:00
Andrzej Krzemienski	d4a4a5b6ad	fixed C++98-incompatible unit test	2020-01-16 22:31:23 +01:00
Robert Leahy	9581804efa	GCC 4.4.7: boost::in_place & Assignment Assigning a boost::in_place_factory to a boost::optional templated on a type which was trivially copyable failed to compile under GCC 4.4.7.	2019-12-23 11:24:39 -05:00
Robert Leahy	d07ae78901	Tests Pass in GCC 4.4.7 Several tests either did not compile or failed upon running when using GCC 4.4.7.	2019-12-23 11:24:39 -05:00
Robert Leahy	683dbe2412	.travis.yml: Specify Trusty for Trusty Addons Previously .travis.yml didn't specify dist: trusty when using addons which were specifically for Trusty. This led to the Clang 5 build failing when trying to install Clang 5.	2019-12-23 11:24:39 -05:00
Andrzej Krzemienski	010ee00604	Update release notes	2019-12-20 00:30:37 +01:00
Andrzej Krzemienski	13bc27698e	Add test case for fix to issue #78	2019-12-20 00:18:52 +01:00
Andrzej Krzemienski	0481b05d1f	Merge branch 'cxx20_fix' of https://github.com/CaseyCarter/optional into CaseyCarter-cxx20_fix	2019-12-19 20:56:34 +01:00
Andrzej Krzemienski	4c863f5bf8	Merge branch 'master' into develop	2019-12-19 20:52:53 +01:00
Andrey Semashev	9ed20cb085	Marked none instances as inline variables. This should avoid duplicating none instances in all translation units. Closes https://github.com/boostorg/optional/issues/33.	2019-12-19 20:22:16 +01:00
Casey Carter	4fbb7582e1	Don't instantiate is_convertible_to_T_or_factory when is_optional_related Fixes #78.	2019-12-18 17:51:51 -08:00
Andrzej Krzemieński	29dfc173c6	Merge pull request #71 from Mike-Devel/min_cmake [CMake] Add minimal cmake support	2019-03-04 10:43:45 +01:00
Mike Dev	f4d1107e86	[CMake] Add minimal cmake support - CMake file only supports add_subdirectory workflow. - Provides Boost::optional target, but no installation and no unit tests	2019-03-02 17:12:29 +01:00
Andrzej Krzemieński	324272fc0e	Merge pull request #70 from Kojoley/patch-1 Fix unused argument warning	2019-02-27 21:22:08 -10:00
Nikita Kniazev	ee575b34c5	Fix unused argument warning boost/optional/optional.hpp:970:5: warning: unused parameter 'rhs' [-Wunused-parameter]	2019-02-28 00:13:00 +03:00
Matt	b709447922	r #12967 use BOOST_CONSTEXPR on none_t ctor	2017-08-16 13:52:46 -04:00
Matt	cd4e44f3dc	r #12967 make none_t constructor constexpr	2017-04-13 09:13:26 -04:00
Nikita Kniazev	c3abf83426	Suppress weak vtables warning	2016-08-31 17:37:50 +03:00