Re: [Chicken-hackers] [Chicken-users] [PATCH] Make library tests compare numbers within epsilon

[Jim Ursetto]

I am curious why this happens though.  The only thing I could think of was the 
number is being constant folded in one case or being computed in one case via a 
hardware intrinsic instead of libm in the other, but the generated C code looks 
identical in both cases.  Perhaps some previous register state makes the values 
be off slightly, but to a degree gcc deems acceptable with -O2?  

It's also possible there is a genuine error.  Any ideas?  I'd be curious to see 
the generated asm.

On May 29, 2013, at 3:28 PM, Sven Hartrumpf <address@hidden> wrote:

> Hi Peter.
> 
> Wed, 29 May 2013 19:06:26 +0200, Peter.Bex wrote:
>> This patch should fix it, but it does in a roundabout way: converting
>> the number to a string causes it to lose precision because of the default
>> value of (flonum-print-precision).  It's more explicit to check whether
>> the two values lie within an epsilon of eachother, like the test egg does.
> 
> I hoped that there will be a better patch. Thanks, Peter.
> 
>> Could you try whether "make check" on a -O3-compiled CHICKEN succeeds
>> with the attached patch?
> 
> It does!
> (Also for -O2.)
> 
> Ciao
> Sven
> 
> _______________________________________________
> Chicken-hackers mailing list
> address@hidden
> https://lists.nongnu.org/mailman/listinfo/chicken-hackers