Floating point rounding modes: we should restrict them slightly

[Walter Bright]

Walter Bright wrote:
> Don wrote:
>> PROPOSAL:
>> Change the spec by adding the line to float.html:
>> "If the floating-point rounding mode is changed within a function, it 
>> must be restored before the function exits. If this rule is violated 
>> (for example, by the use of inline asm), the rounding mode used for 
>> subsequent calculations is undefined."
> 
> But that doesn't allow for changing the rounding mode at a global level, 
> then rerunning one's computation to determine how rounding affects their 
> final result.

Ok, I understand now. This makes sense.