[External] : Re: Verification in agent transformers

[Alan Bateman]

On 10/03/2025 18:25, Ryan Ernst wrote:
> I created a reproduction:
>
> verify-error-repro.png
> rjernst/verify-error-repro 
> <https://urldefense.com/v3/__https://github.com/rjernst/verify-error-repro__;!!ACWV5N9M2RV99hQ!KIEIqqu475SaI3subOAn49baG1td4FYwqRarkv_3BgCYLhaTpVFwf-MKTovjGLmIr4KUnbhvWgfw4Q$>
> github.com 
> <https://urldefense.com/v3/__https://github.com/rjernst/verify-error-repro__;!!ACWV5N9M2RV99hQ!KIEIqqu475SaI3subOAn49baG1td4FYwqRarkv_3BgCYLhaTpVFwf-MKTovjGLmIr4KUnbhvWgfw4Q$>
>
> <https://urldefense.com/v3/__https://github.com/rjernst/verify-error-repro__;!!ACWV5N9M2RV99hQ!KIEIqqu475SaI3subOAn49baG1td4FYwqRarkv_3BgCYLhaTpVFwf-MKTovjGLmIr4KUnbhvWgfw4Q$>
>
> Again, the VerifyError is correct, it’s what we expect (we created bad 
> bytecode in a transform), but it doesn’t always occur.
>
Classes loaded from modules mapped to the boot loader, or classes on the 
boot loader's class path, are not verified if modified at class load 
time. They are verified if redefined at runtime. Developers of agents 
are not infallible so there may be an argument to enable 
BytecodeVerificationLocal when an agent enables one of the 
can_generate_XXX_class_hook_events capabilities.

-Alan
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://mail.openjdk.org/pipermail/hotspot-dev/attachments/20250310/bb19e86d/attachment-0001.htm>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: verify-error-repro.png
Type: image/png
Size: 120561 bytes
Desc: not available
URL: <https://mail.openjdk.org/pipermail/hotspot-dev/attachments/20250310/bb19e86d/verify-error-repro-0001.png>