What does this error mean? There is no stderr or stdout the only error I can find is from the log:
2017-06-06 17:36:09,014 INFO - MaterializeWorkflowDescriptorActor [UUID(000771a9)]: Call-to-Backend assignments: birdseed_to_vcf_wklfw.birdseed_to_vcf -> JES
2017-06-06 17:36:09,078 INFO - JES [UUID(000771a9)]: Creating authentication file for workflow 000771a9-f300-46a5-921e-3ad357319fb4 at
gs://cromwell-auth-vanallen-firecloud-billing/000771a9-f300-46a5-921e-3ad357319fb4_auth.json
2017-06-06 17:36:11,670 INFO - WorkflowExecutionActor-000771a9-f300-46a5-921e-3ad357319fb4 [UUID(000771a9)]: Starting calls: birdseed_to_vcf_wklfw.birdseed_to_vcf:NA:1
2017-06-06 17:36:11,877 ERROR - JesAsyncBackendJobExecutionActor
[UUID(000771a9)birdseed_to_vcf_wklfw.birdseed_to_vcf:NA:1]: Error attempting to Execute
scala.MatchError: null
at wdl4s.expression.ValueEvaluator.evaluate(ValueEvaluator.scala:45)
at wdl4s.expression.ValueEvaluator.evaluate(ValueEvaluator.scala:118)
at wdl4s.expression.ValueEvaluator.evaluate(ValueEvaluator.scala:118)
at wdl4s.expression.ValueEvaluator.evaluate(ValueEvaluator.scala:53)
at wdl4s.expression.ValueEvaluator.evaluate(ValueEvaluator.scala:52)
at wdl4s.WdlExpression$.evaluate(WdlExpression.scala:85)
at wdl4s.WdlExpression.evaluate(WdlExpression.scala:166)
at wdl4s.command.ParameterCommandPart.instantiate(ParameterCommandPart.scala:53)
at wdl4s.Task$$anonfun$instantiateCommand$1$$anonfun$apply$2.apply(Task.scala:108)
at wdl4s.Task$$anonfun$instantiateCommand$1$$anonfun$apply$2.apply(Task.scala:108)
at scala.collection.TraversableLike$$anonfun$map$1.apply(TraversableLike.scala:234)
at scala.collection.TraversableLike$$anonfun$map$1.apply(TraversableLike.scala:234)
at scala.collection.Iterator$class.foreach(Iterator.scala:893)
at scala.collection.AbstractIterator.foreach(Iterator.scala:1336)
at scala.collection.IterableLike$class.foreach(IterableLike.scala:72)
at scala.collection.AbstractIterable.foreach(Iterable.scala:54)
at scala.collection.TraversableLike$class.map(TraversableLike.scala:234)
at scala.collection.AbstractTraversable.map(Traversable.scala:104)
at wdl4s.Task$$anonfun$instantiateCommand$1.apply(Task.scala:108)
at wdl4s.Task$$anonfun$instantiateCommand$1.apply(Task.scala:108)
at scala.util.Try$.apply(Try.scala:192)
at wdl4s.Task.instantiateCommand(Task.scala:108)
at cromwell.backend.wdl.Command$$anonfun$instantiate$1.apply(Command.scala:28)
at cromwell.backend.wdl.Command$$anonfun$instantiate$1.apply(Command.scala:27)
at scala.util.Success.flatMap(Try.scala:231)
at cromwell.backend.wdl.Command$.instantiate(Command.scala:27)
at cromwell.backend.standard.StandardAsyncExecutionActor$class.instantiatedCommand(StandardAsyncExecutionActor.scala:206)
at cromwell.backend.impl.jes.JesAsyncBackendJobExecutionActor.instantiatedCommand$lzycompute(JesAsyncBackendJobExecutionActor.scala:67)
at cromwell.backend.impl.jes.JesAsyncBackendJobExecutionActor.instantiatedCommand(JesAsyncBackendJobExecutionActor.scala:67)
at cromwell.backend.standard.StandardAsyncExecutionActor$class.commandScriptContents(StandardAsyncExecutionActor.scala:177)
at cromwell.backend.impl.jes.JesAsyncBackendJobExecutionActor.commandScriptContents(JesAsyncBackendJobExecutionActor.scala:67)
at cromwell.backend.impl.jes.JesAsyncBackendJobExecutionActor.cromwell$backend$impl$jes$JesAsyncBackendJobExecutionActor$$uploadScriptFile$1(JesAsyncBackendJobExecutionActor.scala:301)
at cromwell.backend.impl.jes.JesAsyncBackendJobExecutionActor$$anonfun$runWithJes$1$$anonfun$apply$3.apply(JesAsyncBackendJobExecutionActor.scala:315)
at cromwell.backend.impl.jes.JesAsyncBackendJobExecutionActor$$anonfun$runWithJes$1$$anonfun$apply$3.apply(JesAsyncBackendJobExecutionActor.scala:314)
at scala.concurrent.Future$$anonfun$flatMap$1.apply(Future.scala:253)
at scala.concurrent.Future$$anonfun$flatMap$1.apply(Future.scala:251)
at scala.concurrent.impl.CallbackRunnable.run(Promise.scala:32)
at akka.dispatch.BatchingExecutor$AbstractBatch.processBatch(BatchingExecutor.scala:55)
at akka.dispatch.BatchingExecutor$BlockableBatch$$anonfun$run$1.apply$mcV$sp(BatchingExecutor.scala:91)
at akka.dispatch.BatchingExecutor$BlockableBatch$$anonfun$run$1.apply(BatchingExecutor.scala:91)
at akka.dispatch.BatchingExecutor$BlockableBatch$$anonfun$run$1.apply(BatchingExecutor.scala:91)
at scala.concurrent.BlockContext$.withBlockContext(BlockContext.scala:72)
at akka.dispatch.BatchingExecutor$BlockableBatch.run(BatchingExecutor.scala:90)
at akka.dispatch.TaskInvocation.run(AbstractDispatcher.scala:39)
at akka.dispatch.ForkJoinExecutorConfigurator$AkkaForkJoinTask.exec(AbstractDispatcher.scala:415)
at scala.concurrent.forkjoin.ForkJoinTask.doExec(ForkJoinTask.java:260)
at scala.concurrent.forkjoin.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1339)
at scala.concurrent.forkjoin.ForkJoinPool.runWorker(ForkJoinPool.java:1979)
at scala.concurrent.forkjoin.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:107)
2017-06-06 17:36:13,927 INFO - $h [UUID(000771a9)]: Copying workflow logs from /cromwell-workflow-logs/workflow.000771a9-f300-46a5-921e-3ad357319fb4.log to gs://fc-bb7e37f6-c15e-4f83-b468-23003a8ba3ff/d1294b07-55bc-4471-823b-d57c41566ce3/workflow.logs/workflow.000771a9-f300-46a5-921e-3ad357319fb4.log