Build boost with C++14

.ci/script.sh

@@ -2,6 +2,17 @@
 
 set -ex
 
+if [ $TRAVIS_OS_NAME == linux ]; then
+    export CC=${C_COMPILER}
+    export CXX=${CXX_COMPILER}
+
+    sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/${C_COMPILER} 10
+    sudo update-alternatives --install /usr/bin/g++ g++ /usr/bin/${CXX_COMPILER} 10
+
+    sudo update-alternatives --set gcc "/usr/bin/${C_COMPILER}"
+    sudo update-alternatives --set g++ "/usr/bin/${CXX_COMPILER}"
+fi
+
 if [ $TRAVIS_OS_NAME == linux ]; then
     source /opt/qt${QT_PKG}/bin/qt${QT_PKG}-env.sh || true;
 fi

deps/cmake/Boost.cmake

@@ -16,7 +16,7 @@ ExternalProject_Add(
   CONFIGURE_COMMAND ${DEPS_BUILD_DIR}/boost/bootstrap.sh
     --with-libraries=random,thread,system,iostreams,atomic,chrono,date_time,regex
     --prefix=${DEPS_INSTALL_DIR}
-  BUILD_COMMAND ${DEPS_BUILD_DIR}/boost/b2 -d0 variant=release link=static threading=multi --layout=system
+  BUILD_COMMAND ${DEPS_BUILD_DIR}/boost/b2 -d0 cxxstd=14 variant=release link=static threading=multi --layout=system
   INSTALL_COMMAND ${DEPS_BUILD_DIR}/boost/b2 -d0 install
 )