Github user ilooner commented on a diff in the pull request: https://github.com/apache/drill/pull/1045#discussion_r162501868 --- Diff: exec/java-exec/src/test/java/org/apache/drill/exec/physical/impl/xsort/managed/TestSorter.java --- @@ -59,7 +59,7 @@ @Category(OperatorTest.class) public class TestSorter extends DrillTest { - public static OperatorFixture fixture; + public volatile static OperatorFixture fixture; --- End diff -- I was running into an issue where the fixture variable was consistently null when the test ran. This seemed impossible and I hypothesized that JUnit is secretly using two threads, one to call the static initializers and then another to actually execute the test methods. So I made the variable volatile and the issue went away. I agree this is weird and it raises the question why other tests don't have the same issue. I'll remove the volatile for now, if the bizarre issue surfaces again, I will get more details and post them here.
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