[GHC] #3353: Add CLDouble support

[GHC]

#3353: Add CLDouble support
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        Reporter:  igloo             |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  ⊥
       Component:  Compiler          |              Version:  6.12.1
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by claude):

 Replying to [comment:8 simonmar]:
 > As a workaround, code that needs `CLDouble` can go via a C wrapper that
 takes a `CLDouble *`.  Avoid manipulating `CLDouble` directly in Haskell,
 just talk in terms of pointers to `CLDouble`.

 I recently had such a need, so wrote a small package to help:
 https://hackage.haskell.org/package/long-double

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/3353#comment:12>
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