[GHC] #3674: Recognise language pragmas generated by custom pre-processors (run with -F)

[GHC]

#3674: Recognise language pragmas generated by custom pre-processors (run with -F)
-----------------------------------------+----------------------------------
  Reporter:  dorchard                    |          Owner:  dorchard              
      Type:  bug                         |         Status:  new                   
  Priority:  normal                      |      Milestone:  6.14.1                
 Component:  Driver                      |        Version:                        
Resolution:                              |       Keywords:  customer pre-processor
Difficulty:  Moderate (less than a day)  |             Os:  Unknown/Multiple      
  Testcase:                              |   Architecture:  Unknown/Multiple      
   Failure:  GHC rejects valid program   |  
-----------------------------------------+----------------------------------
Changes (by duncan):

  * difficulty:  => Moderate (less than a day)
  * type:  feature request => bug
  * component:  Compiler => Driver
  * milestone:  => 6.14.1

Comment:

 #3457 and #2464 are bugs with the same fix.

 They are all instances of the same problem in the way ghc handles
 information gleaned from source files prior to pre-processing (with cpp or
 a custom pre-processor).

 See #3457 for a description.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/3674#comment:1>
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