Incrementally building the OpenJDK microbenchmarks emit a "Note: Benchmark entries for <class>already exists, overwriting" for each microbenchmark class. This is generated by the JMH BenchmarkProcessor annotation processor via the javac messager framework.

Supplying -nowarn works, but that suppresses everything. To carefully disable this without disabling linters and other warnings it seems one option is to supply the -XDsuppressNotes flag to the javac execution.