JVM crash by creating VarHandle

[Maurizio Cimadamore]

On 02/02/2020 01:51, Ty Young wrote:
> I'm not entirely sure what could be done differently but If you have 
> suggestions then I'd be glad to hear it. The thing to keep in mind 
> with NVML is that it's backwards and cross-platform compatible so once 
> things are defined there isn't anything to really worry about later.
>
>
> In hindsight the NativeFunction implementations shouldn't force the 
> use of higher level abstractions - that should be the job of 
> nvml_h.java as it's what enforces type safety to begin with. 

I wasn't suggesting you should change the API - just that there are many 
layers between the code you see in Test and the actual method handle, 
var handle calls - which makes it harder to diagnose.

Re-reading the stack trace in the crash, it seems to be a problem 
related with classfile parsing, potentially of one of the synthetic 
VarHandle classes which we spin on the fly. I'll do more analysis next week.

In the meantime it would be helpful to understand if the crash started 
to appear when you updated the Panama repository (which might suggest 
some relationship with recent commits, such as the one for adding 
VarHandle adapter support), or if it's a failure that you encountered 
writing a new test.

Maurizio