Re: [Bug-apl] fractional power ¯8⋆÷3

[Xiao-Yong Jin]

Exactly so.  ‘-Ofast -fno-finite-math-only’ gives correct results.
What’s going on here?  I don’t expect this has anything to do with NaN or Inf.

> On Apr 13, 2016, at 2:13 PM, Jay Foad <address@hidden> wrote:
> 
> I'd guess -ffinite-math-only.
> 
> Jay.
> 
> On 13 April 2016 at 19:36, Xiao-Yong Jin <address@hidden> wrote:
>> Looks like a gcc optimization problem (clang works correctly).
>> Using ‘-Ofast’ with gcc 5.3 reproduces the bug.
>> Using ‘-O3’ works fine.
>> 
>> So one of the options down here caused the bug:
>> -fassociative-math
>> -fcx-limited-range
>> -ffinite-math-only
>> -fmath-errno
>> -freciprocal-math
>> -fsigned-zeros
>> -ftrapping-math
>> -funsafe-math-optimizations
>> 
>> I’ll see if I can pin down exactly which one.  Do you have any idea what 
>> could be the culprit?
>> 
>> - Xiao-Yong
>> 
>> 
>>> On Apr 13, 2016, at 1:01 PM, Juergen Sauermann <address@hidden> wrote:
>>> 
>>> Hi Xiao,
>>> 
>>> interesting. I am still getting this in *SVN**719*:
>>> 
>>> *      8 ¯8⋆÷3
>>> 2 1J1.732050808*
>>> 
>>> /// Jürgwn
>>> 
>>> 
>>> On 04/13/2016 03:42 AM, Xiao-Yong Jin wrote:
>>>> Hi,
>>>> 
>>>> With the svn version 719,
>>>> 
>>>>      8 ¯8⋆÷3
>>>> 2 0.000000000
>>>> 
>>>> but with the release version 1.5,
>>>> 
>>>>      8 ¯8⋆÷3
>>>> 2 1J1.732050808
>>>> 
>>>> Best,
>>>> Xiao-Yong
>>>> 
>>>> 
>>>> 
>>> 
>> 
>>