Re: How PostgreSQL's floating-point hurts everyone everywhere

At 4:47 PM +0000 7/20/00, Thomas Lockhart wrote:
>Typically, machines will trap overflow/underflow/NaN problems in
>floating point, but silently ignore these properties with integer
>arithmetic. It would be nice to have consistant behavior across all
>types, but I'll stick to floats for discussion now.

The IEEE standard says that that behavior must be configurable.  The 
standard behavior in Fortran is to ignore floating point exceptions 
as well.  Unfortunately the name of the C routine which changes it is 
not defined in the standard.

This is a bit off-topic but we have this problem with the DS1 
spacecraft software.  Everything is run with the exceptions enabled 
because we don't want to allow those values undetected in the 
attitude control calculations.  OTOH we are vulnerable to reboots 
(and have had one) due to mistakes in other code.


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