From below job log, it looks Jtreg does not have long path support during javac.
http://scaaa008.us.oracle.com:9502/runs%2F474611.CORELIBS-JDK-NIGHTLY-JTREG-1/results/workDir/javax/xml/jaxp/unittest/bug6526547/Bug.jtr
When using testNG.dirs=testLocation, Jtreg will compile all files in it like:
compile -XDignore.symbol.file=true -implicit:none fullName1 fullName2....fullNameN
It will crash when it contains many files in testNG.dirs
http://scaaa008.us.oracle.com:9502/runs%2F474611.CORELIBS-JDK-NIGHTLY-JTREG-1/results/workDir/javax/xml/jaxp/unittest/bug6526547/Bug.jtr
When using testNG.dirs=testLocation, Jtreg will compile all files in it like:
compile -XDignore.symbol.file=true -implicit:none fullName1 fullName2....fullNameN
It will crash when it contains many files in testNG.dirs