compiler/graalunit/CoreTest.java timed out

The following test failed in the JDK15 CI:

compiler/graalunit/CoreTest.java

Here's a snippet from the log file (not much help):

org.graalvm.compiler.core.test.SwitchFoldingTest finished 30.0 ms
org.graalvm.compiler.core.test.SwitchTest started (122 of 160)
  run1: Passed 5.6 ms
org.graalvm.compiler.core.test.SwitchTest finished 5.9 ms
org.graalvm.compiler.core.test.TrivialInliningExplosionTest started (123 of 160)
  test: ];
 stderr: []
 exitValue = 134

java.lang.RuntimeException: Expected to get exit value of [0]

at jdk.test.lib.process.OutputAnalyzer.shouldHaveExitValue(OutputAnalyzer.java:455)
at compiler.graalunit.common.GraalUnitTestLauncher.main(GraalUnitTestLauncher.java:293)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
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.MainWrapper$MainThread.run(MainWrapper.java:127)
at java.base/java.lang.Thread.run(Thread.java:832)

JavaTest Message: Test threw exception: java.lang.RuntimeException: Expected to get exit value of [0]

JavaTest Message: shutting down test

STATUS:Failed.`main' threw exception: java.lang.RuntimeException: Expected to get exit value of [0]
----------rerun:(35/7967)*----------

The test failed with an "exitValue = 134". According to the end
of the log file:

result: Error. Program `/System/Volumes/Data/mesos/work_dir/jib-master/install/jdk-15+18-736/macosx-x64-open.jdk/jdk-15.jdk/Contents/Home/bin/java' timed out (timeout set to 480000ms, elapsed time including timeout handling was 507068ms).

so it's likely that the "exitValue = 134" is caused by the
timeout handler.There is a core file, but no hs_err_pid
file in the artifacts.