java.lang.NullPointerException at org.hl7.fhir.r5.comparison.ProfileComparer.checkAddTypeUnion(ProfileComparer.java:600) at org.hl7.fhir.r5.comparison.ProfileComparer.unionTypes(ProfileComparer.java:536) at org.hl7.fhir.r5.comparison.ProfileComparer.compareElements(ProfileComparer.java:228) at org.hl7.fhir.r5.comparison.ProfileComparer.compareChildren(ProfileComparer.java:329) at org.hl7.fhir.r5.comparison.ProfileComparer.compareElements(ProfileComparer.java:245) at org.hl7.fhir.r5.comparison.ProfileComparer.compare(ProfileComparer.java:147) at org.hl7.fhir.r5.comparison.ComparisonSession.compare(ComparisonSession.java:97) at org.hl7.fhir.r5.comparison.ProfileComparer.checkAddTypeUnion(ProfileComparer.java:599) at org.hl7.fhir.r5.comparison.ProfileComparer.unionTypes(ProfileComparer.java:536) at org.hl7.fhir.r5.comparison.ProfileComparer.compareElements(ProfileComparer.java:228) at org.hl7.fhir.r5.comparison.ProfileComparer.compareChildren(ProfileComparer.java:329) at org.hl7.fhir.r5.comparison.ProfileComparer.compareElements(ProfileComparer.java:245) at org.hl7.fhir.r5.comparison.ProfileComparer.compare(ProfileComparer.java:147) at org.hl7.fhir.r5.comparison.ComparisonSession.compare(ComparisonSession.java:97) at org.hl7.fhir.igtools.publisher.comparators.PreviousVersionComparator.finishChecks(PreviousVersionComparator.java:262) at org.hl7.fhir.igtools.publisher.Publisher.checkConformanceResources(Publisher.java:4951) at org.hl7.fhir.igtools.publisher.Publisher.loadConformance(Publisher.java:4850) at org.hl7.fhir.igtools.publisher.Publisher.createIg(Publisher.java:1051) at org.hl7.fhir.igtools.publisher.Publisher.execute(Publisher.java:901) at org.hl7.fhir.igtools.publisher.Publisher.main(Publisher.java:10439) at org.hl7.fhir.igtools.publisher.utils.PublicationProcess.runBuild(PublicationProcess.java:332) at org.hl7.fhir.igtools.publisher.utils.PublicationProcess.doPublish(PublicationProcess.java:231) at org.hl7.fhir.igtools.publisher.utils.PublicationProcess.publishInner(PublicationProcess.java:180) at org.hl7.fhir.igtools.publisher.utils.PublicationProcess.publish(PublicationProcess.java:61) at org.hl7.fhir.igtools.publisher.Publisher.main(Publisher.java:10202)