System.NullReferenceException while taking heap snapshot

Version: P2.0.42 (64 bit)
Max Dump K objects: 250
Freeze: No
Save ETL: No

Tail of log:

1070.1s: Dumped 114,354,847 objects, max_dump_limit 134,217,716 Dumper heap Size 7,384MB
HeapDump Error: System.NullReferenceException: Object reference not set to an instance of an object.
   at System.Collections.Generic.SegmentedList`1.Add(T item)
   at Graphs.Node.WriteCompressedInt(SegmentedMemoryStreamWriter writer, Int32 value)
   at Graphs.Graph.SetNodeTypeAndSize(NodeIndex nodeIndex, NodeTypeIndex typeIndex, Int32 sizeInBytes)
   at Graphs.Graph.SetNode(NodeIndex nodeIndex, NodeTypeIndex typeIndex, Int32 sizeInBytes, GrowableArray`1 children)
   at GCHeapDumper.DumpAllSegments()
   at GCHeapDumper.DumpDotNetHeapDataWorker(ClrHeap heap, ICorDebugProcess& debugProcess, Boolean isDump, Double retryScale)
   at GCHeapDumper.DumpDotNetHeapData(ClrHeap heap, ICorDebugProcess& debugProcess, Boolean isDump)
   at GCHeapDumper.TryGetDotNetDump(Int32 processID)
   at GCHeapDumper.CaptureLiveHeapDump(Int32 processID)
   at GCHeapDumper.DumpLiveHeap(Int32 processID)
   at Program.MainWorker(String[] args)


Completed: Dumping GC Heap to c:\temp\20190613.gcDump   (Elapsed Time: 1071.709 sec)
Error: HeapDump failed with exit code 1