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From: Simon Pilgrim <simon.pilgrim@gecm.com>
Subject: Re: Renaming Fixed Point Mutiplicative operator in Ada 95
Date: 1998/05/21
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Date: 1998-05-21T00:00:00+00:00
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Robert Dewar wrote:
<< Incidentally, in a critical system, I would jolly well hope that
EITHER

  a) you prove that division by zero cannot happen

 or

  b) you test for it explicitly
 
     if z = 0 then
         ....
     else
         a := y /z;
     end if;           >> 

It is not sufficient to just check for equality to zero with fixed point
types.  If z is small enough then a divide by zero exception will still
be generated by some targets (Intel 486 & Motorola 68k for example).

Regards,

Simon Pilgrim