[GHC] #3304: define gcd 0 0 = 0

[GHC]

#3304: define gcd 0 0 = 0
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  Reporter:  stevec          |          Owner:                  
      Type:  proposal        |         Status:  patch           
  Priority:  normal          |      Milestone:  7.2.1           
 Component:  libraries/base  |        Version:  7.1             
Resolution:                  |       Keywords:                  
  Testcase:                  |      Blockedby:                  
Difficulty:  Unknown         |             Os:  Unknown/Multiple
  Blocking:                  |   Architecture:  Unknown/Multiple
   Failure:  None/Unknown    |  
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Changes (by daniel.is.fischer):

  * version:  6.10.3 => 7.1


Comment:

 The last patch isn't directly related to the proposal, but since it came
 up in the thread, I'm attaching it here nevertheless. It changes the
 behaviour to match the docs more closely. With signed bounded integer
 types, many results of `gcd` are negative if one of the arguments is
 `minBound`, calling a final `abs` eliminates those except if the result is
 `minBound`.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/3304#comment:13>
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