RFR: 8253899: Make IsClassUnloadingEnabled signature match specification [v2]

[Vladimir Kempik]

On Mon, 5 Oct 2020 12:44:34 GMT, Vladimir Kempik <vkempik at openjdk.org> wrote:

>>> _Mailing list message from [David Holmes](mailto:david.holmes at oracle.com) on
>>> [hotspot-dev](mailto:hotspot-dev at openjdk.java.net):_
>>> Hi Vladimir,
>>> 
>>> On 2/10/2020 5:37 pm, Vladimir Kempik wrote:
>>> 
>>> > On Fri, 2 Oct 2020 07:27:17 GMT, David Holmes <dholmes at openjdk.org> wrote:
>>> > > Okay but look at the example that documentation gives:
>>> > > > For example, if the jvmtiParamInfo returned by GetExtensionEvents indicates that there is a jint parameter, the event
>>> > > > handler should be declared: ```
>>> > > > void JNICALL myHandler(jvmtiEnv* jvmti_env, jint myInt, ...)
>>> > > > ```
>>> > > 
>>> > > 
>>> > > The myInt is explicit, just as our "jboolean* enabled" is explicit. I think they key point is that the signature must
>>> > > end with "..." which it does.
>>> > > I don't see anything here that needs to be fixed.
>>> > 
>>> > 
>>> > Hello David. On majority of platforms this would be fine.
>>> > But on some platforms, variadic arguments and non variadic arguments are passed differently ( for example on
>>> > macos-aarch64, variadic args are passed always on stack, non variadic on registers (and on stack for 9th+ arg) , that
>>> > causes issues.
>>> 
>>> Okay - I see the potential for a problme here but ...
>>> 
>>> > If you still see no issues here we can delay and make this changeset part of JEP-391.
>>> > But since this changeset isn't much macos-aarch64 specific, I thought it would be good to integrate it separately from
>>> > jep-391.
>>> 
>>> ... this change actually goes against the example in the spec, so if you
>>> make this change it indicates the spec needs to be updated too.
>>> 
>>> Cheers,
>>> David
>>> -----
>> 
>> Hello David
>> 
>> I really believe the problem is in document here ( in examples)
>> first, the doc clearly specify the type
>> 
>> typedef jvmtiError (JNICALL *jvmtiExtensionFunction)
>>     (jvmtiEnv* jvmti_env,
>>       ...);
>> 
>> then in examples it declares the function not matching this spec.
>> 
>> Is it a good idea to update the docs in a separate bug ?
>> 
>> Thanks, Vladimir
>
> Hello David
> I have created CSR draft
> https://bugs.openjdk.java.net/browse/JDK-8254014
> 
> Regards, Vladimir

Hello
I have updated the PR with changes from spec of CSR

Regards, Vladimir

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

PR: https://git.openjdk.java.net/jdk/pull/466