If I do a jdk10 release build with clang-4.0, I see a crash in Unsafe_PutByte

# SIGSEGV (0xb) at pc=0x00002afabac59096, pid=31795, tid=31796
#
# JRE version: OpenJDK Runtime Environment (10.0) (build 10-internal+0-adhoc.martin.jdk10-hs-clang-4.0)
# Java VM: OpenJDK 64-Bit Server VM (10-internal+0-adhoc.martin.jdk10-hs-clang-4.0, mixed mode, tiered, compressed oops, serial gc, linux-amd64)
# Problematic frame:
# V [libjvm.so+0xb29096] Unsafe_PutByte(JNIEnv_*, _jobject*, _jobject*, long, signed char)+0x116

Recipe:
bash ./configure --with-toolchain-type=clang --disable-warnings-as-errors --with-toolchain-path=/usr/lib/llvm-4.0/bin --with-extra-ldflags=-z execstack --disable-precompiled-headers --with-cacerts-file=/etc/ssl/certs/java/cacerts --enable-unlimited-crypto --with-native-debug-symbols=none --with-default-make-target=jdk-image test-image --with-boot-jdk=/home/martin/jdk/jdk9