The result of Math.log(3.0) is different on x86_64 and aarch64?

[Tianhua huang]

Thank you all :)  Now it be more clear to me.

On Tue, Jul 30, 2019 at 2:26 AM Joe Darcy <joe.darcy at oracle.com> wrote:

> tl;dr if you need reproduciblity, use StrictMath.log rather than Math.log.
>
> Also note that this alias is a broad alias for the development of the
> JDK; it is not a support alias or dedicated forum to submit bugs.
>
> IMO, this thread is off-topic for this alias and such inquiries would be
> better directed to a bug reporting location, such as
> https://bugreport.java.com/bugreport/, or elsewhere.
>
> Cheers,
>
> -Joe
>
> On 7/25/2019 1:11 AM, Tianhua huang wrote:
> > Sorry to disturb you again, I took some tests of java.lang.Math.log
> > function on aarch64 server, I met a strange case, the result of
> > Math.log(3.0) is different with x86_64:
> > on x86_64:
> > scala> Math.log(3.0) res50: Double = 1.0986122886681098
> >
> > but on aarch64:
> > scala> Math.log(3.0) res19: Double = 1.0986122886681096
> >
> > Then I tried  Math.log(4.0), Math.log(5.0) and some other numbers, the
> > results on x86_64 and aarch64 are same, why Math.log(3.0) is so special?
> > this confused me much, I think the result of
> > Math.log(Double) should be same across platforms, right?
>