RFR (XXS) JDK-8139768 Running with -XX:CMSOldPLABNumRefills=2147483648 causes EXCEPTION_INT_DIVIDE_BY_ZERO on Windows i586

Joseph Provino joseph.provino at oracle.com
Wed Dec 9 21:07:31 UTC 2015

On 12/9/2015 2:03 PM, Jesper Wilhelmsson wrote:
> Hi Joe,
> Looks OK, but there is one thing I'm not 100% sure about, what is the 
> precedence in C++, will the cast to double be done before or after the 
> multiplication?
> I'm thinking that maybe you need ((double)CMSOldPLABToleranceFactor)*...
> If the overflow happens and the zero is then cast to double, I guess 
> that the division might go through anyway since there is no exact 
> floating point zero, so it may hide the bug rather than fixing it. I'm 
> not sure if this is a real issue.
I thought the cast to double would bind more tightly than the multiply.  
But to be safe, I'll add the parens.



> /Jesper
> Den 9/12/15 kl. 19:30, skrev Joseph Provino:
>> Please review this very small change.
>> CR: https://bugs.openjdk.java.net/browse/JDK-8139768
>> Webrev:  http://cr.openjdk.java.net/~jprovino/8139768/webrev.00
>> thanks.
>> joe

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