Eugene:

So basically I am trying to run a test in the form of:

@Benchmark
@Fork(jvmArgsAppend = "-Djava.lang.invoke.stringConcat=java.lang.invoke.StringConcatFactory.Strategy.BC_SB", value = 1)
public String java9StringBuilder(ThreadState state) {
    // some implementation here
}

Running it with:

java -jar benchmarks.jar MyFullClassNameHere -v extra

Unfortunately it fails with forked VM failed with exit code 1 and no more "verbose" output.

What I am doing wrong?

I do get these warnings:

WARNING: Unknown module: org.openjdk specified to --add-exports

WARNING: An Illegal Reflective access operation has occurred

WARNING: Illegal reflective access by org.openjdk.jmh.util.Utils (file:/Path/Here/benchmarks.jar) to field java.io.Console.cs

WARNING: Please consider reporting this to the maintainers of org.openjdk.jmh.util.Utils

WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations

WARNING: All illegal access operations will be denied in a future release