From Tyler Steele:
I see two failures in ProcessBuilder/Basic.java that result from the same source. The expected output is constructed with LIBPATH which is not the same between parent and child process, so the parent (test) process does not construct the correct expected output.
 
Failing output:
 
# Failure 1:
>'=C:=\\,LIBPATH=/home/jenkins/temp/openjdk/jdk-fork/build/aix-ppc64-server-release/images/jdk/lib/server:/home/jenkins/temp/openjdk/jdk-fork/build/aix-ppc64-server-release/images/jdk/lib:/home/jenkins/temp/openjdk/jdk-fork/build/aix-ppc64-server-release/images/jdk/../lib,'< not equal to '=C:=\\,LIBPATH=/home/jenkins/temp/openjdk/jdk-fork/build/aix-ppc64-server-release/images/jdk/lib/server:/home/jenkins/temp/openjdk/jdk-fork/build/aix-ppc64-server-release/images/jdk/lib:/home/jenkins/temp/openjdk/jdk-fork/build/aix-ppc64-server-release/images/jdk/../lib:/home/jenkins/temp/openjdk/jdk-fork/build/aix-ppc64-server-release/images/test/jdk/jtreg/native,'

java.lang.Exception: Stack trace
        at java.base/java.lang.Thread.dumpStack(Thread.java:1380)
        at Basic.fail(Basic.java:2825)
        at Basic.fail(Basic.java:2826)
        at Basic.equal(Basic.java:2832)
        at Basic.realMain(Basic.java:1886)
        at Basic.main(Basic.java:2835)
        at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:104)
        at java.base/java.lang.reflect.Method.invoke(Method.java:577)
        at com.sun.javatest.regtest.agent.MainWrapper$MainThread.run(MainWrapper.java:127)
        at java.base/java.lang.Thread.run(Thread.java:833)

# Failure 2:

Incorrect handling of envstrings containing NULs
java.lang.Exception: Stack trace
        at java.base/java.lang.Thread.dumpStack(Thread.java:1380)
        at Basic.fail(Basic.java:2825)
        at Basic.fail(Basic.java:2826)
        at Basic.check(Basic.java:2829)
        at Basic.realMain(Basic.java:1940)
        at Basic.main(Basic.java:2835)
        at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:104)
        at java.base/java.lang.reflect.Method.invoke(Method.java:577)
        at com.sun.javatest.regtest.agent.MainWrapper$MainThread.run(MainWrapper.java:127)
        at java.base/java.lang.Thread.run(Thread.java:833)
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