https://bugs.openjdk.org/browse/JDK-8294982 added several --add-exports in make/RunTest.gmk, which are passed as VM arguments when running micro benchmarks through make.

On Windows when running under WSL, it seems like fixpath is translating the / in these flags to \, and as a result a runtime exception occurs while running the benchmarks:

Error occurred during initialization of boot layer
java.lang.RuntimeException: Unable to parse --add-exports <module>/<package>: java.base\jdk.internal.org.objectweb.asm.tree
<forked VM failed with exit code 1>
<stdout last='20 lines'>
Error occurred during initialization of boot layer
java.lang.RuntimeException: Unable to parse --add-exports <module>/<package>: java.base\jdk.internal.org.objectweb.asm.tree
</stdout>
<stderr last='20 lines'>
</stderr>