"illegal reflective access operation" warning when profiling

Starting the profiler under JDK10 gives the following warning:

WARNING: An illegal reflective access operation has occurred
WARNING: Illegal reflective access by org.netbeans.lib.profiler.server.ClassLoaderManager to method java.lang.ClassLoader.findLoadedClass(java.lang.String)
WARNING: Please consider reporting this to the maintainers of org.netbeans.lib.profiler.server.ClassLoaderManager
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

I see it twice: once in messages.log during VM calibration, then again in the output window when the profiler starts.