The following test failed in the JDK15 CI:

runtime/cds/appcds/TestZGCWithCDS.java

Here's a snippet from the log file:

----------System.err:(26/1483)----------
 stdout: [[0.267s][info][cds] Archive was created with UseCompressedOops = 0, UseCompressedClassPointers = 0
[0.267s][info][cds] Mapped static region #0 at base 0x0000000800000000 top 0x0000000800007000 (MiscCode)
[0.267s][info][cds] Mapped static region #1 at base 0x0000000800007000 top 0x0000000800437000 (ReadWrite)
[0.267s][info][cds] Mapped static region #2 at base 0x0000000800437000 top 0x0000000800b73000 (ReadOnly)
Hello World
];
 stderr: [java version "15-ea" 2020-09-15
Java(TM) SE Runtime Environment (fastdebug build 15-ea+22-1023)
Java HotSpot(TM) 64-Bit Server VM (fastdebug build 15-ea+22-1023, mixed mode, sharing)
]
 exitValue = 0

java.lang.RuntimeException: 'Unable to use shared archive.' missing from stdout/stderr

at jdk.test.lib.process.OutputAnalyzer.shouldContain(OutputAnalyzer.java:187)
at TestZGCWithCDS.main(TestZGCWithCDS.java:97)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:64)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:564)
at com.sun.javatest.regtest.agent.MainActionHelper$AgentVMRunnable.run(MainActionHelper.java:298)
at java.base/java.lang.Thread.run(Thread.java:832)

JavaTest Message: Test threw exception: java.lang.RuntimeException
JavaTest Message: shutting down test

result: Failed. Execution failed: `main' threw exception: java.lang.RuntimeException: 'Unable to use shared archive.' missing from stdout/stderr

So far the failure has been spotted on Linux-X64 and Win-X64.