Re: Fixed-point question

[Patrick Noffke <patrick.noffke@gmail.com>]

On Friday, June 26, 2015 at 11:44:07 PM UTC-5, Jeffrey R. Carter wrote:
> On 06/26/2015 08:00 PM, Patrick Noffke wrote:
> > On Friday, June 26, 2015 at 6:13:11 PM UTC-5, qunying wrote:
> >> In my test with Linux x86_64 with FSF GNAT 4.9.2
> >>
> >> C1 :=  14.664
> >> C2 :=  17.000
> >> Small :=  3.90625000000000000E-03
> >> 1/180 :=  5.55555555555555556E-03
> >>
> >> With Jeffrey's changes I got:
> >> C1 :=  14.667
> >> C2 :=  18.000
> >> Small :=  5.55555555555555556E-03
> >> 1/180 :=  5.55555555555555556E-03
> >>
> > 
> > So is this a bug, is the ARM not clear on what should happen here, or is it expected?
> 
> With a small of 1/180:
> 
> For C1, AFAICT, the compiler will calculate N/D exactly, getting 44/3 =
> 14.6666...., and then convert this to Fixed_type, getting 2640/180.
> 
> For C2, "/" for Fixed_Type is used, so N and D are converted to Fixed_Type
> first. 

My question is whether this is the right thing for the compiler to do.

Pat