Suggested fix for JDK-4724038 (Add unmap method to MappedByteBuffer)

[Vitaly Davidovich]

Sure, if we're comfortable saying that the only cause of NPE there is due
to this and not something else.

On Thu, Sep 10, 2015 at 10:37 AM, David M. Lloyd <david.lloyd at redhat.com>
wrote:

> Or, the Java methods which wrap this access can just catch NPE and throw
> the new exception type.
>
>
> On 09/10/2015 09:35 AM, Vitaly Davidovich wrote:
>
>> Well, you'd probably want something other than NPE here -- perhaps a new
>> dedicated exception to signal this condition.  And this means the segfault
>> handling now needs to know about this type of situation as well, rather
>> than just NPEs.
>>
>> On Thu, Sep 10, 2015 at 10:32 AM, Andrew Haley <aph at redhat.com> wrote:
>>
>> On 09/10/2015 03:26 PM, Vitaly Davidovich wrote:
>>>
>>>> Yes, so what happens when that guard page is accessed by a thread after
>>>>
>>> safepoint?
>>>
>>> A segfault and a null pointer exception.
>>>
>>> Andrew.
>>>
>>>
>>>
> --
> - DML
>