I've been running all of :jdk_lang multiple times on all platforms. I noticed on macosx-x64-debug this test times out about 3 out of 50 runs. I don't think it is stuck. It appears to run to completion and pass, but takes a bit too long to do so, so the timeout fire and jtreg fails the test as a result. Probably the macosx-x64 host is just on the slow side and this issue can be resolved with a longer timeout.

----------System.out:(11/374)----------
Result: 499999500000 in 90464 ms
Result: 499999500000 in 197012 ms
Result: 499999500000 in 69233 ms
Result: 499999500000 in 159140 ms
Result: 499999500000 in 89703 ms
Result: 499999500000 in 153510 ms
Result: 499999500000 in 145766 ms
Result: 499999500000 in 188763 ms
Timeout signalled after 1200 seconds
Result: 499999500000 in 196227 ms
Result: 499999500000 in 109406 ms
----------System.err:(1/15)----------
STATUS:Passed.