[GHC] #7630: FFI: "capi" calling convention doesn't work

[GHC]

#7630: FFI: "capi" calling convention doesn't work
----------------------------------------+-----------------------------------
  Reporter:  guest                      |          Owner:         
      Type:  bug                        |         Status:  new    
  Priority:  normal                     |      Milestone:         
 Component:  Compiler                   |        Version:  7.6.1  
Resolution:                             |       Keywords:         
        Os:  Linux                      |   Architecture:  x86    
   Failure:  GHC rejects valid program  |     Difficulty:  Unknown
  Testcase:                             |      Blockedby:         
  Blocking:                             |        Related:         
----------------------------------------+-----------------------------------
Changes (by guest):

  * status:  closed => new
  * failure:  None/Unknown => GHC rejects valid program
  * resolution:  invalid =>


Comment:

 I did but ghc doesn't accept it:
 {{{
 % cat capi.hs
 {-# LANGUAGE ForeignFunctionInterface, CAPI #-}

 import Foreign.C

 foreign import capi "math.h value M_PI" mPI :: CDouble

 main :: IO ()
 main = print mPI

 % ghc capi.hs

 capi.hs:1:40: Unsupported extension: CAPI
 }}}

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7630#comment:2>
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