The following test failed in the JDK21 CI:

runtime/ClassUnload/DictionaryDependsTest.java

Here's a snippet from the log file:

#section:main
----------messages:(7/563)----------
command: main -Xbootclasspath/a:. -Xmn8m -XX:+UnlockDiagnosticVMOptions -Xlog:class+unload -XX:+WhiteBoxAPI DictionaryDependsTest
reason: User specified action: run main/othervm -Xbootclasspath/a:. -Xmn8m -XX:+UnlockDiagnosticVMOptions -Xlog:class+unload -XX:+WhiteBoxAPI DictionaryDependsTest
started: Fri Jan 27 17:01:22 UTC 2023
Mode: othervm [/othervm specified]
Additional options from @modules: --add-modules java.base,java.compiler --add-exports java.base/jdk.internal.misc=ALL-UNNAMED
finished: Fri Jan 27 17:01:22 UTC 2023
elapsed time (seconds): 0.444
----------configuration:(4/111)----------
Boot Layer
  add modules: java.base java.compiler
  add exports: java.base/jdk.internal.misc ALL-UNNAMED

----------System.out:(15/1247)----------
name is DictionaryDependsTest$c1r
name is p2.c2
c2 method2 called
[0.261s][info][class,unload] unloading class java.lang.invoke.LambdaForm$MH/0x0000000801007000 0x0000000801007000
[0.261s][info][class,unload] unloading class java.lang.invoke.LambdaForm$MH/0x0000000801006c00 0x0000000801006c00
[0.261s][info][class,unload] unloading class java.lang.invoke.LambdaForm$DMH/0x0000000801006800 0x0000000801006800
[0.261s][info][class,unload] unloading class java.lang.invoke.LambdaForm$MH/0x0000000801004000 0x0000000801004000
[0.262s][info][class,unload] unloading class java.lang.invoke.LambdaForm$MH/0x0000000801003800 0x0000000801003800
[0.262s][info][class,unload] unloading class java.lang.invoke.LambdaForm$MH/0x0000000801000400 0x0000000801000400
c2 method2 called
[0.335s][info][class,unload] unloading class java.lang.invoke.LambdaForm$MH/0x0000000801000400 0x0000000801000400
[0.335s][info][class,unload] unloading class java.lang.invoke.LambdaForm$MH/0x0000000801003800 0x0000000801003800
[0.335s][info][class,unload] unloading class java.lang.invoke.LambdaForm$DMH/0x0000000801004000 0x0000000801004000
Should not unload anything before here because class DictionaryDependsTest$c1r is still alive.
Should unload MyTest and p2.c2 just now
----------System.err:(12/830)----------
jdk.test.lib.classloader.ClassUnloadCommon$TestFailure: Test failed: should be unloaded
at jdk.test.lib.classloader.ClassUnloadCommon.failIf(ClassUnloadCommon.java:51)
at DictionaryDependsTest.main(DictionaryDependsTest.java:87)
at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:104)
at java.base/java.lang.reflect.Method.invoke(Method.java:578)
at com.sun.javatest.regtest.agent.MainWrapper$MainThread.run(MainWrapper.java:125)
at java.base/java.lang.Thread.run(Thread.java:1623)

JavaTest Message: Test threw exception: jdk.test.lib.classloader.ClassUnloadCommon$TestFailure: Test failed: should be unloaded
JavaTest Message: shutting down test

STATUS:Failed.`main' threw exception: jdk.test.lib.classloader.ClassUnloadCommon$TestFailure: Test failed: should be unloaded
----------rerun:(44/8489)*----------