a.lang.foreign.Arena,java.lang.foreign.Linker.Option...)">upcall stub</a>
    and there is no caller class on the stack, it is as if the restricted method call occurred in an <em>unnamed module</em>.</p>
<p>In the reference implementation, access to restricted methods can be granted to
    specific modules using the command line option <code>--enable-native-access=M1,M2, ... Mn</code>,
    where <code>M1</code>, <code>M2</code>, <code>... Mn</code> are module names (for the unnamed module,
    the special v