RFR: 8371216: oopDesc::print_value_on breaks if klass is garbage [v2]

[Martin Doerr]

On Fri, 7 Nov 2025 10:04:35 GMT, Thomas Stuefe <stuefe at openjdk.org> wrote:

>> Paul Hübner has updated the pull request incrementally with one additional commit since the last revision:
>> 
>>   Don't make a new function.
>
> I would not add the helper function for only one case. We already have a bunch of helpers like these. Just test for oop != NULL at the call site.

> Thanks for the feedback and reviews @tstuefe @coleenp @TheRealMDoerr. I'll integrate this on Monday when the 24h period has passed and my test re-runs are finished.
> 
> > I think there are more places which cause "error occurred during error reporting" due to assertions, but they can get addressed in separate issues.
> 
> If you have any examples, either now or down the road, I'd be happy to take a look.

An prominent example in the debug build is the following assertion: https://github.com/openjdk/jdk/blob/master/src/hotspot/share/oops/compressedKlass.inline.hpp#L91
The code is used by CompressedKlassPointers::decode_not_null. The error reporting code shouldn't use the version with assertions while investigating if a value may be a compressed class pointer.

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

PR Comment: https://git.openjdk.org/jdk/pull/28190#issuecomment-3503465658