The following tests fail when run with Valhalla migrated classes because they use a WeakHashMap and try to store instances of one of those migrated classes into it:
  - java/util/Collection/IteratorAtEnd.java
  - java/util/Map/Get.java
  - java/util/Map/LockStep.java
  - java/util/Map/ToArray.java

Moved spliterator issues to JDK-8336672
  - java/util/Spliterator/SpliteratorCharacteristics.java
  - java/util/Spliterator/SpliteratorFailFastTest.java
  - java/util/Spliterator/SpliteratorLateBindingTest.java
  - java/util/Spliterator/SpliteratorTraversingAndSplittingTest.java

To reproduce the issue, run those test with a Valhalla build and the --enable-preview flag.

The typical stack trace looks like that:

java.lang.IdentityException: java.lang.Integer is not an identity class
at java.base/java.util.WeakHashMap.newValueEntry(WeakHashMap.java:584)
at java.base/java.util.WeakHashMap.put(WeakHashMap.java:553)
at IteratorAtEnd.testMap(IteratorAtEnd.java:102)
at IteratorAtEnd.realMain(IteratorAtEnd.java:84)
at IteratorAtEnd.main(IteratorAtEnd.java:156)
at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:103)
at java.base/java.lang.reflect.Method.invoke(Method.java:580)
at com.sun.javatest.regtest.agent.MainActionHelper$AgentVMRunnable.run(MainActionHelper.java:333)
at java.base/java.lang.Thread.run(Thread.java:1575)
java.lang.AssertionError: Some tests failed
at IteratorAtEnd.main(IteratorAtEnd.java:158)
at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:103)
at java.base/java.lang.reflect.Method.invoke(Method.java:580)
at com.sun.javatest.regtest.agent.MainActionHelper$AgentVMRunnable.run(MainActionHelper.java:333)
at java.base/java.lang.Thread.run(Thread.java:1575)