RFR (S) 8185590: ShouldNotReachHere from ClassLoaderData::try_get_next_class()

[Aleksey Shipilev]

On 08/01/2017 04:45 PM, Zhengyu Gu wrote:
> On 08/01/2017 10:32 AM, coleen.phillimore at oracle.com wrote:
>>
>>
>> On 8/1/17 10:23 AM, Aleksey Shipilev wrote:
>>> On 08/01/2017 04:18 PM, coleen.phillimore at oracle.com wrote:
>>>> Summary: Counting number of instanceKlass code didn't work.
>>>>
>>>> A late code review change caused this regression.   Tested with
>>>> internal NSK mlvm tests with
>>>> -XX:-TieredCompilation -XX:CompileThreshold=100 including the one
>>>> where I reproduced the failure
>>>> overnight.
>>>>
>>>> open webrev at http://cr.openjdk.java.net/~coleenp/8185590.01/webrev
>>> Hm, so now that the loop variable is _conditionally_ incremented, what
>>> guarantees the loop termination?
>>
>> The fact that number_of_classes can't be zero so something has to be
>> returned?

I see! Your current patch seems to be the lesser evil, comparing to alternatives I have. I would
probably add the circuit breaker suggested by Zhengyu to be extra safe, but that looks not that
critical.

Looks good!

-Aleksey