Compressed oops failure with hs19 master

[Tom Rodriguez]

Just FYI, I've got a test case and fix for this.  I'll be sending out a request for review soon but basically there's some code that skips unneeded zeroing for instances but it mistakenly gets applied to arrays because the array header is that same size as regular objects with compressed oops.

tom

On Nov 24, 2010, at 2:31 PM, Dr Andrew John Hughes wrote:

> On 24 November 2010 22:11, Tom Rodriguez <tom.rodriguez at oracle.com> wrote:
>> I can reproduce this with the latest hotspot.  I've filed 7002666 for it.  You may want to disable compressed oops in hs19.
>> 
> 
> Thanks Tom.  We've already disabled compressed oops in IcedTea6 (see
> http://blog.fuseyism.com/index.php/2010/11/24/icedtea6-176-183-and-192-released/).
> I've suggested it to Joe for OpenJDK6
> (http://mail.openjdk.java.net/pipermail/jdk6-dev/2010-November/002117.html)
> but no response as yet.
> 
>> tom
>> 
>> On Nov 24, 2010, at 12:24 PM, Dr Andrew John Hughes wrote:
>> 
>>> I reported this on jdk6-dev
>>> (http://mail.openjdk.java.net/pipermail/jdk6-dev/2010-November/002095.html)
>>> but thought it best to also report it here as there's been no
>>> response.
>>> 
>>> The hs19 stable branch crashes with Eclipse's CDT plugin:
>>> 
>>> https://bugzilla.redhat.com/show_bug.cgi?id=647737
>>> 
>>> and the same occurs with the current OpenJDK7 HotSpot tree.
>>> (http://hg.openjdk.java.net/jdk7/hotspot/hotspot)
>>> 
>>> Disabling compressed oops by default (as was done for hs17 stable)
>>> will work around the problem, and this is what we presently do in
>>> IcedTea6.
>>> 
>>> Is compressed oops ready for prime time in hs19 or is turning it off
>>> the right path to go down?  Has anyone else seen this issue or know of
>>> anything that might fix it?
>>> 
>>> --
>>> Andrew :)
>>> 
>>> Free Java Software Engineer
>>> Red Hat, Inc. (http://www.redhat.com)
>>> 
>>> Support Free Java!
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>> 
>> 
> 
> 
> 
> -- 
> Andrew :-)
> 
> Free Java Software Engineer
> Red Hat, Inc. (http://www.redhat.com)
> 
> Support Free Java!
> Contribute to GNU Classpath and the OpenJDK
> http://www.gnu.org/software/classpath
> http://openjdk.java.net
> 
> PGP Key: 94EFD9D8 (http://subkeys.pgp.net)
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