Changes between Version 2 and Version 3 of Commentary/CmmExceptions


Ignore:
Timestamp:
Jan 5, 2007 9:02:23 PM (7 years ago)
Author:
p_tanski
Comment:

brief note on bug #1042

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  • Commentary/CmmExceptions

    v2 v3  
    1515 * FPU exceptions may be unavoidable, especially if several FPU operations are serially performed at the machine level so the higher level software has no opportunity to check the results in between operations.  
    1616 
     17There is at least one problem in GHC that requires FPU exception handling.  See bug ticket #1042.  The bug occurs in 'show'ing the number (conversion from base_2 to base_10).  Note that the FPU exception does not occur on PowerPC machines. 
     18 
     19[Note: placeholder until I can track down the original message --PT] 
     20 
     21The following code will ''fail'' to produce a floating point exception or NaN on x86 machines (recall that 0.0/0.0 is NaN ''and'' a definite FPU exception): 
     22 
     23[in GHCi]: 
     24Prelude> realToFrac (0/0 :: Float) :: Double