A number of our older tests were written to only run the test code on particular platforms, and immediately exit on other platforms. A couple examples of how this is done:

if (File.separatorChar != '\\') {
    /* This test is only valid on win32 systems */
    return;
}

or

if (!System.getProperty("os.name").contains("OS X")) {
    System.out.println("Test only run on MAC. Exiting.");
    return;
}

But now that we have jtreg's @requires tag, these tests can be tagged to only run on the relevant platforms. This should prevent these tests from being run, and superficial results being generated, on unnecessary platforms.