[GHC] #3353: Add CLDouble support

[GHC]

#3353: Add CLDouble support
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    Reporter:  igloo             |        Owner:              
        Type:  bug               |       Status:  new         
    Priority:  normal            |    Milestone:  _|_         
   Component:  Compiler          |      Version:  6.12.1      
    Keywords:                    |   Difficulty:  Unknown     
          Os:  Unknown/Multiple  |     Testcase:              
Architecture:  Unknown/Multiple  |      Failure:  None/Unknown
       Patch:  0                 |  
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Changes (by ksf):

 * cc: barsoap@… (added)
  * patch:  => 0


Comment:

 http://grouper.ieee.org/groups/754/meeting-materials/2001-07-18-c99.pdf

 states that

 long double == IEEE double extended, else non-IEEE wide type, else IEEE
 double

 Long double wasn't standardised before C99 and afaik the FFI addendum
 doesn't specify any particular C standard to adhere to, which means that
 GHC (without CLDouble) right now doesn't comply with the FFI although
 CLDouble does not have to be quad precision.

 I opt for quick re-inclusion of CLDouble, be it as quad precision or not.
 An alias to CDouble, or a binding to the x87's 80bit type is a perfectly
 ok thing to do.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/3353#comment:6>
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