Mach 5 9-hs detected test failures due to this changeset:
Date: 2017-02-15 22:19 -0500
8166188: G1 Needs pre barrier on dereference of weak JNI handles
Summary: Add low tag to jweaks and G1 barrier for jweak loads.
Reviewed-by: mgerdin, mdoerr, pliden, dlong, dcubed, coleenp, aph, tschatzl
Contributed-by: email@example.com, firstname.lastname@example.org, email@example.com
which was pushed at 2028 PT/2128 MT/2328 ET so it did not make the 1900 PT
2017.02.15 nightly cutoff. Mach5's 14 test failures appear to all be in JDK
tests... Of course, we don't know if there will be additional failures in
JDK9-hs nightly testing.
So the good news: Mach5 detected this failure earlier than we would
have seen it with our normal HotSpot nightly! And with the email
notification to all of the folks involved, there has already been
eight follow-up messages (I don't count this one).