$config{HAS_CLOCK_GETTIME} = run_test 'clock_gettime()', test_file($config{CXX}, 'clock_gettime.cpp', $^O eq 'darwin' ? undef : '-lrt');
$config{HAS_EVENTFD} = run_test 'eventfd()', test_file($config{CXX}, 'eventfd.cpp');
$config{HAS_CLOCK_GETTIME} = run_test 'clock_gettime()', test_file($config{CXX}, 'clock_gettime.cpp', $^O eq 'darwin' ? undef : '-lrt');
$config{HAS_EVENTFD} = run_test 'eventfd()', test_file($config{CXX}, 'eventfd.cpp');