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

[Vladimir Kozlov]

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
>