Supporting C++20

ci/Dockerfile

@@ -1,4 +1,4 @@
-FROM ubuntu:18.04
+FROM ubuntu:20.04
 
 WORKDIR /setup-ci
 
@@ -9,9 +9,17 @@ ADD install_bazelisk.sh /setup-ci
 ADD install_protobuf.sh /setup-ci
 ADD install_format_tools.sh /setup-ci
 
+ENV DEBIAN_FRONTEND noninteractive
+ENV DEBCONF_NONINTERACTIVE_SEEN true
+
+RUN echo "tzdata tzdata/Areas select US" > /tmp/preseed.txt; \
+    echo "tzdata tzdata/Zones/Europe select Chicago" >> /tmp/preseed.txt; \
+    debconf-set-selections /tmp/preseed.txt && \
+    apt-get update && \
+    apt-get install -y tzdata
+
 RUN /setup-ci/setup_ci_environment.sh \
   && /setup-ci/setup_cmake.sh \
-  && /setup-ci/install_gcc48.sh \
   && /setup-ci/install_bazelisk.sh \
   && /setup-ci/install_protobuf.sh \
   && /setup-ci/install_format_tools.sh

ci/do_ci.sh

@@ -21,6 +21,7 @@ if [[ "$1" == "cmake.test" ]]; then
   make test
   exit 0
 elif [[ "$1" == "cmake.c++20.test" ]]; then
+  echo "${BUILD_DIR}"
   cd "${BUILD_DIR}"
   rm -rf *
   cmake -DCMAKE_BUILD_TYPE=Debug  \

ci/run_docker.sh

@@ -3,12 +3,17 @@
 set -e
 
 BUILD_IMAGE=opentelemetry-cpp-build
+BUILD_IMAGE2=opentelemetry-cpp-build2
 docker image inspect "$BUILD_IMAGE" &> /dev/null || {
   docker build -t "$BUILD_IMAGE" ci
 }
 
-if [[ $# -ge 1 ]]; then
-  docker run -v "$PWD":/src -w /src -it "$BUILD_IMAGE" "$@"
+if [ $2 == cmake.c++20.test ]; then
+  docker run -v "$PWD":/src -w /src -it "$BUILD_IMAGE2" "$@"
 else
-  docker run -v "$PWD":/src -w /src --privileged -it "$BUILD_IMAGE" /bin/bash -l
-fi
+  if [[ $# -ge 1 ]]; then
+    docker run -v "$PWD":/src -w /src -it "$BUILD_IMAGE" "$@"
+  else
+    docker run -v "$PWD":/src -w /src --privileged -it "$BUILD_IMAGE" /bin/bash -l
+  fi
+fi

ci/setup_ci_environment.sh

@@ -6,5 +6,6 @@ apt-get install --no-install-recommends --no-install-suggests -y \
                 build-essential \
                 ca-certificates \
                 wget \
-                git
+                git \
+                g++-10 
 apt-get install -y lcov