RFR (S): JDK-8164086: Checked JNI pending exception check should be cleared when returning to Java frame

[Nils Eliasson]

Hi David,

The platform specific code looks great. Consider that code reviewed.

Regards,
Nils Eliasson

On 2016-09-06 09:51, David Simms wrote:
>
> Updated webrev: http://cr.openjdk.java.net/~dsimms/8164086/webrev3/
>
>
>
> On 06/09/16 01:20, David Holmes wrote:
>> Hi David,
>>
>> On 5/09/2016 6:02 PM, David Simms wrote:
>>> Hi David,
>>>
>>> I can make the checks silent, but the launcher itself produces warnings
>>> from checked JNI (it's use of unchecked Java method invocations), and
>>> this causes the test
>>> (http://cr.openjdk.java.net/~dsimms/8164086/webrev2/hotspot/test/runtime/jni/checked/TestCheckedJniExceptionCheck.java.html) 
>>>
>>> to fail, with unchecked exception warnings popping up in the output.
>>
>> I've looked back at your original changes in this area but I'm still 
>> not seeing exactly where the unchecked back-to-back JNI calls are 
>> happening. For example NewPlatformString can return with an exception 
>> pending, but will return NULL, and the calling code has checks for NULL.
>>
>
> LoadMainClass:
>
> http://hg.openjdk.java.net/jdk9/hs/jdk/file/090cbd92c744/src/java.base/share/native/libjli/java.c#l1530 
>
>
> Calls "CallStaticObjectMethod" from "NewPlatformString", then on line 
> 1531 make another call "CallStaticObjectMethod".
>
> No exception check is made. The Xcheck:jni code cannot interpreter the 
> return value from JNI "Call<X>Method" functions, so it triggers the 
> "unchecked" exception warning at line 1531.
>
>
>>> But yeah, I could adjust the test the ignore any start-up warnings and
>>> drop the changes to the launcher...
>>
>> Unless we can more clearly identify exactly where the launcher has a 
>> problem I would prefer not to involve it in these changes. But I 
>> would like to understand exactly why the launcher is triggering the 
>> check.
>>
>
> Dropped launcher changes, adjusted the test to ignore any previous 
> warnings.
>
> Cheers
> /David Simms