RFR 8223174 : Pattern.compile() can throw confusing NegativeArraySizeException

[Martin Buchholz]

OK, sounds reasonable!

On Fri, May 3, 2019 at 6:32 PM Ivan Gerasimov <ivan.gerasimov at oracle.com>
wrote:

> Thank you Martin for review!
>
> On 5/3/19 6:05 PM, Martin Buchholz wrote:
>
> Test should check that Pattern.compile does not return normally, e.g. by
> throwing AssertionError.  Otherwise LGTM.
>
> Well.  I think, that OOM in this scenario is a limitation of the current
> implementation.
> If the implementation of Pattern changes, so that it won't need to
> allocate that temp array, then it will not have to necessarily throw, as
> the pattern is valid.
>
> With kind regards,
> Ivan
>
> On Fri, May 3, 2019 at 5:54 PM Ivan Gerasimov <ivan.gerasimov at oracle.com>
> wrote:
>
>> Hello!
>>
>> A private method Pattern. RemoveQEQuoting() contains calculation of an
>> array size, which can result in numeric overflow, and cause a confusing
>> NegativeArraySizeException.
>>
>> Would you please help review the fix?
>>
>> Please note, that expressions `j + 2` and `pLen - i` cannot overflow
>> (because j is the index of a substring "\Q", and i is an index < pLen),
>> so they are not wrapped with exactXXX() methods.
>>
>> BUGURL: https://bugs.openjdk.java.net/browse/JDK-8223174
>> WEBREV: http://cr.openjdk.java.net/~igerasim/8223174/00/webrev/
>>
>> --
>> With kind regards,
>> Ivan Gerasimov
>>
>>
> --
> With kind regards,
> Ivan Gerasimov
>
>