Dockerイメージのサイズを最小化

Dockerfile

@@ -7,12 +7,8 @@ ENV PATH=/clang-7.0.0/bin:$PATH
 ENV PATH=/root/.cargo/bin:$PATH
 ENV LD_LIBRARY_PATH=/clang-7.0.0/lib:$LD_LIBRARY_PATH
 
-RUN apt-get update && apt-get install -y --no-install-recommends \
-		autoconf \
-		build-essential \
-		ca-certificates \
-		curl \
-		xz-utils \
+RUN BUILD_DEPS='autoconf build-essential ca-certificates curl xz-utils' \
+	&& apt-get update && apt-get install -y --no-install-recommends $BUILD_DEPS \
 	&& rm -rf /var/lib/apt/lists/* \
 	&& curl -SL http://releases.llvm.org/7.0.0/clang+llvm-7.0.0-x86_64-linux-gnu-ubuntu-16.04.tar.xz | tar -xJC / \
 	&& mv /clang+llvm-7.0.0-x86_64-linux-gnu-ubuntu-16.04 /clang-7.0.0 \
@@ -21,13 +17,13 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
 	&& cd /jemalloc-5.1.0 \
 	&& ./autogen.sh \
 	&& make \
-	&& mkdir -p /usr/local/lib \
 	&& mv lib/libjemalloc.a /usr/local/lib/libjemalloc.a \
 	&& cd - \
-	&& rm -rf /jemalloc-5.1.0
-
-RUN clang -v \
-	&& gcc -v \
-	&& rustc --version
+	&& rm -rf /jemalloc-5.1.0 \
+	&& make \
+	&& rm /usr/local/lib/libjemalloc.a \
+	&& rustup self uninstall -y \
+	&& rm -rf /clang-7.0.0 \
+	&& apt-get purge -y --auto-remove $BUILD_DEPS
 
 CMD [ "/bin/bash" ]