diff --git a/dockerfiles/ubuntu_amd64/Dockerfile b/dockerfiles/ubuntu_amd64/Dockerfile
index 90e31bd980..91b188d1dd 100644
--- a/dockerfiles/ubuntu_amd64/Dockerfile
+++ b/dockerfiles/ubuntu_amd64/Dockerfile
@@ -1,4 +1,11 @@
 FROM ubuntu:16.04
+RUN \
+  apt-get update && \
+  apt-get install -y software-properties-common && \
+  add-apt-repository ppa:ubuntu-toolchain-r/test && \
+  apt-get update && \
+  apt-get install -y g++-7 && \
+  update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-7 60
 # based on sstrakh/xenial-boost-clang but imported as source,
 # due to upstream image being obsolete and we don't need boost.
 RUN apt-get update \
@@ -8,8 +15,6 @@ RUN apt-get update \
 	&& apt-get update \
 	&& apt-get install -y \
 	clang-4.0 \
-	gcc \
-	g++ \
 	git-core \
 	&& ln -s /usr/bin/clang-4.0 /usr/bin/clang \
 	&& ln -s /usr/bin/clang++-4.0 /usr/bin/clang++
diff --git a/dockerfiles/ubuntu_i686/Dockerfile b/dockerfiles/ubuntu_i686/Dockerfile
index 3cfef34bc3..cfc95a6d36 100644
--- a/dockerfiles/ubuntu_i686/Dockerfile
+++ b/dockerfiles/ubuntu_i686/Dockerfile
@@ -1,6 +1,13 @@
 FROM ubuntu:16.04
 RUN dpkg --add-architecture i386
+RUN \
+  apt-get update && \
+  apt-get install -y software-properties-common && \
+  add-apt-repository ppa:ubuntu-toolchain-r/test && \
+  apt-get update && \
+  apt-get install -y g++-7-multilib && \
+  update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-7 60
 RUN apt-get update
 RUN apt-get -y upgrade
-RUN apt-get install --no-install-recommends -y gcc-multilib g++-multilib curl ca-certificates libsdl2-dev:i386 libsdl2-ttf-dev:i386  pkg-config:i386  libjansson-dev:i386 libspeex-dev:i386 libspeexdsp-dev:i386 libcurl4-openssl-dev:i386 libcrypto++-dev:i386 libfontconfig1-dev:i386 libfreetype6-dev:i386 libpng-dev:i386 libzip-dev:i386 libssl-dev:i386 ninja-build
+RUN apt-get install --no-install-recommends -y curl ca-certificates libsdl2-dev:i386 libsdl2-ttf-dev:i386  pkg-config:i386  libjansson-dev:i386 libspeex-dev:i386 libspeexdsp-dev:i386 libcurl4-openssl-dev:i386 libcrypto++-dev:i386 libfontconfig1-dev:i386 libfreetype6-dev:i386 libpng-dev:i386 libzip-dev:i386 libssl-dev:i386 ninja-build
 RUN curl https://cmake.org/files/v3.9/cmake-3.9.4-Linux-x86_64.sh -o cmake.sh && sh cmake.sh --skip-license --exclude-subdir --prefix=/usr/local