[9] RFR(XS): 8081288: erronous free in RegClass::~RegClass()

[Zoltán Majó]

Thank you, Vladimir, for the review!

Best regards,


Zoltan


On 10/08/2015 03:57 PM, Vladimir Kozlov wrote:
> Looks good.
>
> Thanks,
> Vladimir
>
> On 10/8/15 8:36 PM, Zoltán Majó wrote:
>> Hi,
>>
>>
>> please review the patch for JDK-8081288.
>>
>> Bug: https://bugs.openjdk.java.net/browse/JDK-8081288
>>
>>
>> Problem: JDK-8075798 modified the destructor of RegClass to free the
>> _classid field of that class:
>>
>> http://hg.openjdk.java.net/jdk9/jdk9/hotspot/rev/ac291bc3ece2#l5.50
>>
>> This is bad software engineering practice because the _classid field
>> points to a memory region *not* allocated by the class itself
>> (allocation happens in ADLParser::get_ident_common); freeing the memory
>> region in RegClass can also lead to errors if ADLParser is changed in
>> the future to release memory it has allocated.
>>
>> The problem was spotted by Krystal Mok.
>>
>>
>> Solution: Change code to not free _classid.
>>
>> Webrev: http://cr.openjdk.java.net/~zmajo/8081288/webrev.00/
>>
>> Testing: JPRT.
>>
>> Thank you and best regards,
>>
>>
>> Zoltan
>>