On Fri, 3 Oct 2025 19:24:46 GMT, Frederic Parain <[email protected]> wrote:

>> The bug was that in parallelGC it is unsafe to retrieve the K-Klass to find 
>> these properties to re-initialize the moved object.  The moved object has 
>> written over the markWord because it's not preserved.  Adding the code that 
>> we must preserve the mark word because these bits matter fixes the bug 
>> because then the moved object will have these bits.
>
> Replying to myself: The answer seems to be in the comment in 
> oop.inline.hpp:98, but it would be nice to know the exact reason.

I agree, it would be good to have a GC expert explain this @albertnetymk ?  
Paul can follow up with him next week.  I think it's inherent in the 
parallelCompaction algorithm that the klass is lost (and then found again?) at 
this point.

-------------

PR Review Comment: 
https://git.openjdk.org/valhalla/pull/1655#discussion_r2403141248

Reply via email to