RFR: 8374807: Crash in MethodData::extra_data_lock()+0x0 when running -XX:+TraceDeoptimization -XX:-ProfileTraps -XX:-TieredCompilation -Xcomp -version [v4]

[Guanqiang Han]

On Thu, 22 Jan 2026 10:09:46 GMT, Emanuel Peter <epeter at openjdk.org> wrote:

>> @eme64 Thanks for the feedback.
>> 
>> On @requires vm.debug: I’d like to keep it for this reproducer. ProfileTraps is the key knob here: the failure requires ProfileTraps=false (create_if_missing = ProfileTraps, so get_method_data(..., false) may return NULL). Since ProfileTraps is a develop_pd flag and not settable on product builds, this reproducer has to run on a non-product VM (i.e., a debug VM).
>> 
>> On -Xcomp: agreed. I’ll keep it but restrict it with -XX:CompileCommand=compileonly,... so we only compile the relevant method(s).
>> 
>> If that sounds reasonable, I’ll proceed with just the compileonly tightening.
>
> Generally, it would also be nicer to extract a reproducer into a `test` method, and only compile that one. That way, the code shape leading to the crash is preserved. Would that be possible? Otherwise, we risk that someone changes the code shape (maybe in the core libs), and the test would not reproduce any more.

Hi @eme64 @iwanowww , I’ve updated the regression test to keep the reproducer self-contained in a dedicated test() method and restricted compilation to that method only. Could you please take another look?

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PR Review Comment: https://git.openjdk.org/jdk/pull/29147#discussion_r2719423962