Drop OracleLinux LLVM version to 3.8.

Author: chrisseaton

CHANGELOG.md

@@ -33,6 +33,8 @@ Changes:
 
 * Now using the native version of Psych.
 
+* The supported version of LLVM on Oracle Linux has been dropped to 3.8.
+
 * The supported version of Fedora has been dropped to 25, and the supported
   version of LLVM to 3.8, due to LLVM incompatibilities. The instructions for
   installing `libssl` have changed to match.

doc/user/installing-llvm.md

@@ -6,7 +6,7 @@ have success with later versions, but we don't actively test these.
 
 ## Oracle Linux
 
-The tested version of LLVM for Oracle Linux is 4.0.1.
+The tested version of LLVM for Oracle Linux is 3.8.
 
 Oracle Linux does not include recent-enough LLVM packages, so you will have to
 [build LLVM from scratch](https://llvm.org/docs/CMake.html). You'll need to

tool/docker/oraclelinux-llvm/Dockerfile

@@ -3,7 +3,7 @@ FROM oraclelinux:7-slim
 MAINTAINER [email protected]
 
 # Install LLVM from source
-ENV LANG=en_US.UTF-8 WORK_DIR=/tmp/llvm-build LLVM_VERSION=4.0.1
+ENV LANG=en_US.UTF-8 WORK_DIR=/tmp/llvm-build LLVM_VERSION=3.8.0
 ENV LLVM_INSTALL_PREFIX=/opt/llvm-${LLVM_VERSION} LLVM_BUILD_DIR=${WORK_DIR}/llvm-${LLVM_VERSION}
 ENV PATH ${LLVM_INSTALL_PREFIX}/bin:${PATH}
 RUN mkdir $WORK_DIR
@@ -60,3 +60,4 @@ RUN make install
 RUN echo "/opt/llvm-${LLVM_VERSION}/lib64" >> /etc/ld.so.conf.d/llvm-x86_64.conf && ldconfig
 WORKDIR /
 RUN rm -rf ${WORK_DIR}
+RUN clang --version