[GHC] #4381: scaleFloat does not handle overflow correctly.

[GHC]

#4381: scaleFloat does not handle overflow correctly.
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    Reporter:  draconx           |        Owner:  simonmar                   
        Type:  bug               |       Status:  patch                      
    Priority:  normal            |    Milestone:                             
   Component:  libraries/base    |      Version:  6.12.3                     
    Keywords:                    |     Testcase:                             
   Blockedby:                    |   Difficulty:                             
          Os:  Unknown/Multiple  |     Blocking:                             
Architecture:  Unknown/Multiple  |      Failure:  Incorrect result at runtime
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Comment(by daniel.is.fischer):

 I've replaced the patch with the improved one.
 It will not work for types whose exponent field is 30 bits or more, but
 those would fail badly with the current code too. long double has a 16-bit
 exponent, so we have plenty of space beyond that.

 sh validate is running at the moment, will probably take another hour or
 so, validating on your boxes should finish before if you start soon ;)

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/4381#comment:6>
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