From aaa8a9a652d0b86cfb20362beaa6e8a9e323a326 Mon Sep 17 00:00:00 2001
From: Michael Grupp <grupp@magazino.eu>
Date: Wed, 31 Oct 2018 15:34:05 +0100
Subject: [PATCH] Configurable CC/CXX compiler toolchain in Dockerfiles.
 (#1402)

Allows to build Docker images with Clang.
---
 .travis.yml                   | 9 +++++----
 Dockerfile.jessie             | 7 +++++++
 Dockerfile.stretch            | 7 +++++++
 Dockerfile.trusty             | 8 ++++++++
 Dockerfile.trusty.bazel       | 8 ++++++++
 Dockerfile.xenial             | 8 ++++++++
 scripts/install_debs_cmake.sh | 1 +
 7 files changed, 44 insertions(+), 4 deletions(-)

diff --git a/.travis.yml b/.travis.yml
index 9ba2ffe..e81cd9f 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -22,14 +22,15 @@ cache:
     - /home/travis/docker/
 
 env:
-  - LSB_RELEASE=trusty DOCKER_CACHE_FILE=/home/travis/docker/trusty-cache.tar.gz
-  - LSB_RELEASE=xenial DOCKER_CACHE_FILE=/home/travis/docker/xenial-cache.tar.gz
-  - LSB_RELEASE=jessie DOCKER_CACHE_FILE=/home/travis/docker/jessie-cache.tar.gz
-  - LSB_RELEASE=stretch DOCKER_CACHE_FILE=/home/travis/docker/stretch-cache.tar.gz
+  - LSB_RELEASE=trusty DOCKER_CACHE_FILE=/home/travis/docker/trusty-cache.tar.gz CC=gcc CXX=g++
+  - LSB_RELEASE=xenial DOCKER_CACHE_FILE=/home/travis/docker/xenial-cache.tar.gz CC=gcc CXX=g++
+  - LSB_RELEASE=jessie DOCKER_CACHE_FILE=/home/travis/docker/jessie-cache.tar.gz CC=gcc CXX=g++
+  - LSB_RELEASE=stretch DOCKER_CACHE_FILE=/home/travis/docker/stretch-cache.tar.gz CC=gcc CXX=g++
 
 before_install: scripts/load_docker_cache.sh
 
 install: true
 script:
   - docker build ${TRAVIS_BUILD_DIR} -t cartographer:${LSB_RELEASE} -f Dockerfile.${LSB_RELEASE}
+      --build-arg cc=$CC --build-arg cxx=$CXX
   - scripts/save_docker_cache.sh
diff --git a/Dockerfile.jessie b/Dockerfile.jessie
index c67abc1..aca3742 100644
--- a/Dockerfile.jessie
+++ b/Dockerfile.jessie
@@ -14,6 +14,13 @@
 
 FROM debian:jessie
 
+ARG cc
+ARG cxx
+
+# Set the preferred C/C++ compiler toolchain, if given (otherwise default).
+ENV CC=$cc
+ENV CXX=$cxx
+
 # This base image doesn't ship with sudo.
 RUN apt-get update && apt-get install -y sudo && rm -rf /var/lib/apt/lists/*
 
diff --git a/Dockerfile.stretch b/Dockerfile.stretch
index 7cdd617..91d5211 100644
--- a/Dockerfile.stretch
+++ b/Dockerfile.stretch
@@ -14,6 +14,13 @@
 
 FROM debian:stretch
 
+ARG cc
+ARG cxx
+
+# Set the preferred C/C++ compiler toolchain, if given (otherwise default).
+ENV CC=$cc
+ENV CXX=$cxx
+
 # This base image doesn't ship with sudo.
 RUN apt-get update && apt-get install -y sudo && rm -rf /var/lib/apt/lists/*
 
diff --git a/Dockerfile.trusty b/Dockerfile.trusty
index 4c8c799..ac96e93 100644
--- a/Dockerfile.trusty
+++ b/Dockerfile.trusty
@@ -13,6 +13,14 @@
 # limitations under the License.
 
 FROM ubuntu:trusty
+
+ARG cc
+ARG cxx
+
+# Set the preferred C/C++ compiler toolchain, if given (otherwise default).
+ENV CC=$cc
+ENV CXX=$cxx
+
 COPY scripts/install_debs_cmake.sh cartographer/scripts/
 RUN cartographer/scripts/install_debs_cmake.sh && rm -rf /var/lib/apt/lists/*
 COPY scripts/install_ceres.sh cartographer/scripts/
diff --git a/Dockerfile.trusty.bazel b/Dockerfile.trusty.bazel
index 8c5dc37..9e296e8 100644
--- a/Dockerfile.trusty.bazel
+++ b/Dockerfile.trusty.bazel
@@ -13,6 +13,14 @@
 # limitations under the License.
 
 FROM ubuntu:trusty
+
+ARG cc
+ARG cxx
+
+# Set the preferred C/C++ compiler toolchain, if given (otherwise default).
+ENV CC=$cc
+ENV CXX=$cxx
+
 COPY scripts/install_debs_bazel.sh cartographer/scripts/
 RUN cartographer/scripts/install_debs_bazel.sh && rm -rf /var/lib/apt/lists/*
 COPY . cartographer
diff --git a/Dockerfile.xenial b/Dockerfile.xenial
index 7279043..715287b 100644
--- a/Dockerfile.xenial
+++ b/Dockerfile.xenial
@@ -12,8 +12,16 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+
 FROM ubuntu:xenial
 
+ARG cc
+ARG cxx
+
+# Set the preferred C/C++ compiler toolchain, if given (otherwise default).
+ENV CC=$cc
+ENV CXX=$cxx
+
 # This base image doesn't ship with sudo.
 RUN apt-get update && apt-get install -y sudo && rm -rf /var/lib/apt/lists/*
 
diff --git a/scripts/install_debs_cmake.sh b/scripts/install_debs_cmake.sh
index afc0c8d..ce5fca4 100755
--- a/scripts/install_debs_cmake.sh
+++ b/scripts/install_debs_cmake.sh
@@ -35,6 +35,7 @@ else
 fi
 
 sudo apt-get install -y \
+    clang \
     g++ \
     git \
     google-mock \