Remove real type

[Robert Jacques]

On Thu, 22 Apr 2010 01:52:41 -0300, Robert Jacques <sandford at jhu.edu>  
wrote:

> On Wed, 21 Apr 2010 23:48:20 -0300, strtr <strtr at spam.com> wrote:
>
>> abcd Wrote:
>>
>>> On the other hand, being an engineer, I use the reals all the time and
>>> want them to stay. I would use the max precision supported by the cpu
>>> then fixed precision like double any day.
>>>
>>> -sk
>>
>> For me it's the exact opposite, reproducibility/portability is key. My  
>> problem with real is that I am always afraid my floats get upgraded to  
>> them internally somewhere/somehow.
>
> You do realize that the x86 floating point unit _always_ promotes floats  
> and doubles to reals internally? The only way around it is for the  
> compiler to use MMX/SSE unit for everything instead.

P.S. An implication of this is that using any type other than real results  
in inconsistent truncation depending on where/when any compiler stores  
intermediate results outside of the fp.