[Info-vax] JNI problem on I64

[hb]

On 1/26/22 14:24, Arne Vajhøj wrote:
> On 1/26/2022 4:50 AM, hb wrote:
>> On 1/26/22 01:39, Arne Vajhøj wrote:
>>> Code outline:
>>>
>>> ... (JNIEnv *cntx, jobject baobj)
>>> ...
>>> signed char *buf;
>>> ...
>>> buf = (*cntx)->GetByteArrayElements(cntx, baobj, NULL);
>>> ...
>>> ...
>>> ...
>>> (*cntx)->ReleaseByteArrayElements(cntx, baobj, buf, 0);
>>>
>>> VMS Alpha 8.4 with Java 1.5 : works fine
>>>
>>> VMS I64 8.4 with Java 8 : crashes (the output is attached below)
>>> ...
>>
>> Just to make sure it isn't a 32-/64-bit problem: how do you compile? 
>> Java 8 on VMS requires JNIs to use 64-bit pointers.
> 
> I do use /pointer=64.

Although I never tried it from an JNI, I would add a 
lib$signal(ss$_debug); and try to debug the JNI code.

The other option to debug a JNI is to find where and when Java "loads" 
it. In Java 6 there was a Java$dlopen routine. In the debugger you could 
set a break point at that routine and then watch for your JNI to be 
"loaded". Once it is "loaded", you can do a "set image <your-jni>" and 
set break points in your code.