java.lang.NullPointerException at org.hl7.fhir.r5.comparison.ProfileComparer.checkAddTypeUnion(ProfileComparer.java:549) at org.hl7.fhir.r5.comparison.ProfileComparer.unionTypes(ProfileComparer.java:488) at org.hl7.fhir.r5.comparison.ProfileComparer.compareElements(ProfileComparer.java:207) at org.hl7.fhir.r5.comparison.ProfileComparer.compareChildren(ProfileComparer.java:307) at org.hl7.fhir.r5.comparison.ProfileComparer.compareElements(ProfileComparer.java:224) at org.hl7.fhir.r5.comparison.ProfileComparer.compare(ProfileComparer.java:131) at org.hl7.fhir.r5.comparison.ComparisonSession.compare(ComparisonSession.java:92) at org.hl7.fhir.r5.comparison.ProfileComparer.checkAddTypeUnion(ProfileComparer.java:548) at org.hl7.fhir.r5.comparison.ProfileComparer.unionTypes(ProfileComparer.java:488) at org.hl7.fhir.r5.comparison.ProfileComparer.compareElements(ProfileComparer.java:207) at org.hl7.fhir.r5.comparison.ProfileComparer.compareChildren(ProfileComparer.java:307) at org.hl7.fhir.r5.comparison.ProfileComparer.compareElements(ProfileComparer.java:224) at org.hl7.fhir.r5.comparison.ProfileComparer.compare(ProfileComparer.java:131) at org.hl7.fhir.r5.comparison.ComparisonSession.compare(ComparisonSession.java:92) at org.hl7.fhir.igtools.publisher.PreviousVersionComparator.finishChecks(PreviousVersionComparator.java:252) at org.hl7.fhir.igtools.publisher.Publisher.checkConformanceResources(Publisher.java:4012) at org.hl7.fhir.igtools.publisher.Publisher.loadConformance(Publisher.java:3918) at org.hl7.fhir.igtools.publisher.Publisher.createIg(Publisher.java:893) at org.hl7.fhir.igtools.publisher.Publisher.execute(Publisher.java:748) at org.hl7.fhir.igtools.publisher.Publisher.main(Publisher.java:8566) at org.hl7.fhir.igtools.publisher.utils.PublicationProcess.runBuild(PublicationProcess.java:342) at org.hl7.fhir.igtools.publisher.utils.PublicationProcess.doPublish(PublicationProcess.java:241) at org.hl7.fhir.igtools.publisher.utils.PublicationProcess.publishInner(PublicationProcess.java:190) at org.hl7.fhir.igtools.publisher.utils.PublicationProcess.publish(PublicationProcess.java:60) at org.hl7.fhir.igtools.publisher.Publisher.main(Publisher.java:8363)