Liftover NullPointerException

Hi Team,

Sorry if I am using a wrong thread to post an issue with lift over. Let me know if I shall raise a new entry for it but would need your advise for below scenario:

I was trying to use hail lift over on a specific dataset for GRCH38 to GRCH37 conversion. I am getting some null pointer exceptions.

Below is the code I am using:
rg37 = hl.get_reference(‘GRCh37’)
rg38 = hl.get_reference(‘GRCh38’)
rg38.add_liftover('gs://hail-common/references/grch38_to_grch37.over.chain.gz, rg37)
ht = ht.annotate(new_pos=hl.liftover(hl.locus(ht.chr,ht.pos, ‘GRCh38’), ‘GRCh37’))

Error Details:
TaskSetManager: WARN: Lost task 4.0 in stage 0.0 (TID 22, , executor 8): java.lang.NullPointerException
at is.hail.codegen.generated.C0.method1(Unknown Source)
at is.hail.codegen.generated.C0.apply(Unknown Source)
at is.hail.codegen.generated.C0.apply(Unknown Source)
at is.hail.expr.TableMapRows$$anonfun$65$$anonfun$apply$32.apply(Relational.scala:2080)
at is.hail.expr.TableMapRows$$anonfun$65$$anonfun$apply$32.apply(Relational.scala:2079)
at scala.collection.Iterator$$anon$11.next(Iterator.scala:409)
at scala.collection.Iterator$$anon$12.next(Iterator.scala:444)
at scala.collection.Iterator$$anon$11.next(Iterator.scala:409)
at scala.collection.Iterator$$anon$12.next(Iterator.scala:444)
at scala.collection.Iterator$$anon$11.next(Iterator.scala:409)
at scala.collection.Iterator$$anon$12.next(Iterator.scala:444)
at scala.collection.Iterator$$anon$11.next(Iterator.scala:409)
at scala.collection.Iterator$$anon$12.next(Iterator.scala:444)
at scala.collection.Iterator$$anon$11.next(Iterator.scala:409)
at scala.collection.Iterator$$anon$11.next(Iterator.scala:409)
at scala.collection.Iterator$$anon$11.next(Iterator.scala:409)
at org.apache.spark.api.python.SerDeUtil$AutoBatchedPickler.next(SerDeUtil.scala:121)
at org.apache.spark.api.python.SerDeUtil$AutoBatchedPickler.next(SerDeUtil.scala:112)
at scala.collection.Iterator$class.foreach(Iterator.scala:893)
at org.apache.spark.api.python.SerDeUtil$AutoBatchedPickler.foreach(SerDeUtil.scala:112)
at org.apache.spark.api.python.PythonRDD$.writeIteratorToStream(PythonRDD.scala:509)
at org.apache.spark.api.python.PythonRunner$WriterThread$$anonfun$run$3.apply(PythonRDD.scala:333)
at org.apache.spark.util.Utils$.logUncaughtExceptions(Utils.scala:1954)
at org.apache.spark.api.python.PythonRunner$WriterThread.run(PythonRDD.scala:269)

I tried this on a different dataset and it works so wondering if it could be a data issue. Is there a way to get some more logging on it?

Thanks in advance,
Aditya Pandit

1 Like

Moved to a new thread.

This is definitely a Hail bug, but probably data-dependent, which could help us figure out what it is.

What version of hail are you running?

We are using hail 0.2

sorry, full version with git SHA. should be in the error message

Sorry about that.

It’s Hail version devel-6942d090d618

that’s an extremely old version – from before 0.2 was promoted out of beta in October!

Please update to the latest Hail version – I’d be very surprised if the problem persists.

Thanks for the advise. Will check for a version upgrade.