RFR (XS) 8204961: JVMTI jtreg tests build warnings on 32-bit platforms

[David Holmes]

I ran this through our testing and it was fine.

I can sponsor this for you if you like Boris.

Thanks,
David

On 14/06/2018 10:55 PM, David Holmes wrote:
> Hi Boris,
> 
> I added serviceability-dev as JVM TI and its tests are technically 
> serviceability concerns.
> 
> On 14/06/2018 10:39 PM, Boris Ulasevich wrote:
>> Hi all,
>>
>> Please review the following patch:
>>    https://bugs.openjdk.java.net/browse/JDK-8204961
>>    http://cr.openjdk.java.net/~bulasevich/8204961/webrev.01
>>
>> Recently opensourced JVMTI tests gives build warnings for ARM32 build. 
> 
> I'm guessing the compiler version must have changed since we last ran 
> these tests on 32-bit ARM. :)
> 
>> GCC complains about conversion between 4-byte pointer to 8-byte jlong 
>> type which is Ok in this case. I propose to hide warning using 
>> conversion to intptr_t.
> 
> I was concerned about what the warnings might imply but now I see that a 
> JVM TI "tag" is simply a jlong used to funnel real pointers around to 
> use for the tagging. So on 32-bit the upper 32-bits of the tag will 
> always be zero and there is no data loss in any of the conversions.
> 
> So assuming none of the other compilers complain about this, this seems 
> fine to me.
> 
> Thanks,
> David
> 
>> thanks,
>> Boris