[9] RFR (XS): JDK-8151020: [TESTBUG] UnsafeGetStableArrayElement::testL_* fail intermittently

Vladimir Ivanov vladimir.x.ivanov at oracle.com
Wed Mar 2 12:11:50 UTC 2016

Thanks, Aleksey.

>> Some cases in UnsafeGetStableArrayElement are not reliable: there's no
>> way to ensure that only some part of an OOP is 0 or not.
> So the test fails when "new Object()" OOP has zeros in some bits, and
> reading shorter bit stride from that OOP makes the test believe that the
> field was "unchanged". Bummer.
Moreover, "important bits" can intermittently become 0 during execution 
(particular object location after some GC). So, it is really hard to 
reliably predict what value a compiler reads.

Best regards,
Vladimir Ivanov

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