The test

   java/lang/Runtime/exec/Duped.java

fails if the child process performs this check on line 43:

   (System.in.available() != 0)

earlier than the parent process has a chance to write to the output stream (line 79).

The failure is fairly easy to reproduce by compiling the test standalone and running it in -Xcomp mode. As the child is started in default -Xmixed mode, it runs "faster" than the parent, and the test fails in roughly one case out of 3:

$ javac Duped.java
$ java -Xcomp Duped
Exception in thread "main" java.lang.Exception: Failed, read ``''
at Duped.main(Duped.java:87)

As we dont mind if the child blocks on the read call when there is no data available yet and this is even desirable, I think that the check on line 43 (System.in.available() != 0) is superfluos. Removing it fixes the issue.