RFR: JDK-8211161: java.lang.ArithmeticException: divide by zero from java.text.DecimalFormat.format()

[joe darcy]

Hello,

It may be reasonable to replace a divide by zero with check for a 
floating-point -0.0 with a bit-level check, but the stated motivation is 
not reasonable.

The Java platform requires that floating-point divide by zero return an 
infinity (or NaN as the case may be) and it is *incorrect* and 
non-conformant to throw an ArithmeticException in that case. Such 
behavior violates the language the JVM specs.

Cheers,

-Joe


On 9/26/2018 9:33 AM, Nasser Ebrahim wrote:
> Hello,
>
> In java.text.DecimalFormat.format(), there is a validation to check
> whether a number is negative zero or not and for that divide by zero is
> used to check for negative infinity which caused the ArithmeticException
> when SIGFPE is enabled in the system. Andrew has opened a bug on my
> behalf. Thank you Andrew.
>
> The corresponding bug is https://bugs.openjdk.java.net/browse/JDK-8211161.
>
> The webrev and stand alone test case is uploaded to
> http://cr.openjdk.java.net/~aleonard/8211161/.
> The recreate step is documented in the bug description.
>
> I have tested the fix with the test cases of the following bugs and
> confirm that it is working.
> https://bugs.java.com/view_bug.do?bug_id=4106658
> https://bugs.java.com/view_bug.do?bug_id=4106667
> https://bugs.java.com/view_bug.do?bug_id=4147706
>
> I did not add any new jtreg test for the current issue as it is not
> functional. Hope that is fine.
>
> Kindly request you to review and comment.
>
> Thank you,
> Nasser Ebrahim
>