From: ThatWouldBeTelling@thevillage.com   
      
   Thomas Koenig wrote:   
   > Kent Dickey  schrieb:   
   >   
   >> This is my point: I don't see a great way to encode the first NaN, which   
   >> is why I propose not making that a goal.  You're not getting the first   
   >> NaN in any case even if you try to do so in hardware, since the order of   
   >> operations is a fragile thing that's hard to control unless you write   
   >> assembly code, or the most tedious source code imaginable.   
   >   
   > Using Fortran, parentheses have to be honored.  If you write   
   >   
   >  A = (B + C) + (D + E)   
   >   
   > then B + C and D + E  have to be calculated before the total sum.   
   > If you write   
   >   
   >   A = B + (C + (D + E))   
   >   
   > then you prescribe the order completetely.   
   >   
   > I can imagine source code that is much more tedious than this :-)   
      
   That doesn't control which variable is assigned to each source operand.   
   If both operands were Nan's and the two-Nan-rule was "always take src1"   
   then the choice of which to propagate would still be non-deterministic.   
      
   --- SoupGate-Win32 v1.05   
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