The following exception happened after attaching to the core file and trying to dump the heap:

java.lang.ClassCastException: class sun.jvm.hotspot.oops.ObjArray cannot be cast to class sun.jvm.hotspot.oops.Instance (sun.jvm.hotspot.oops.ObjArray and sun.jvm.hotspot.oops.Instance are in module jdk.hotspot.agent of loader 'app')
at jdk.hotspot.agent/sun.jvm.hotspot.oops.VMOopHandle.resolve(VMOopHandle.java:61)
at jdk.hotspot.agent/sun.jvm.hotspot.oops.Klass.getJavaMirror(Klass.java:114)
at jdk.hotspot.agent/sun.jvm.hotspot.utilities.HeapHprofBinWriter$5.visit(HeapHprofBinWriter.java:1140)
at jdk.hotspot.agent/sun.jvm.hotspot.classfile.ClassLoaderData.classesDo(ClassLoaderData.java:114)
at jdk.hotspot.agent/sun.jvm.hotspot.classfile.ClassLoaderDataGraph.classesDo(ClassLoaderDataGraph.java:84)
at jdk.hotspot.agent/sun.jvm.hotspot.utilities.HeapHprofBinWriter.writeClasses(HeapHprofBinWriter.java:1137)
at jdk.hotspot.agent/sun.jvm.hotspot.utilities.HeapHprofBinWriter.write(HeapHprofBinWriter.java:460)
at jdk.hotspot.agent/sun.jvm.hotspot.tools.JMap.writeHeapHprofBin(JMap.java:216)
at jdk.hotspot.agent/sun.jvm.hotspot.tools.JMap.run(JMap.java:103)
at jdk.hotspot.agent/sun.jvm.hotspot.tools.Tool.startInternal(Tool.java:278)
at jdk.hotspot.agent/sun.jvm.hotspot.tools.Tool.start(Tool.java:241)
at jdk.hotspot.agent/sun.jvm.hotspot.tools.Tool.execute(Tool.java:134)
at jdk.hotspot.agent/sun.jvm.hotspot.tools.JMap.main(JMap.java:202)
at jdk.hotspot.agent/sun.jvm.hotspot.SALauncher.runJMAP(SALauncher.java:340)
at jdk.hotspot.agent/sun.jvm.hotspot.SALauncher.main(SALauncher.java:500)