[GHC] #8015: GHC is inconsistent about where LANGUAGE is unsupported.

[GHC]

#8015: GHC is inconsistent about where LANGUAGE is unsupported.
-------------------------------------+-------------------------------------
              Reporter:              |            Owner:
  thoughtpolice                      |           Status:  new
                  Type:  bug         |        Milestone:
              Priority:  normal      |          Version:  7.6.3
             Component:  Compiler    |         Keywords:  parser
            Resolution:              |     Architecture:  Unknown/Multiple
      Operating System:              |       Difficulty:  Unknown
  Unknown/Multiple                   |       Blocked By:
       Type of failure:  Incorrect   |  Related Tickets:
  warning at compile-time            |
             Test Case:              |
              Blocking:              |
Differential Revisions:              |
-------------------------------------+-------------------------------------
Changes (by thomie):

 * difficulty:   => Unknown
 * failure:  GHC accepts invalid program => Incorrect warning at compile-
              time


Comment:

 From the
 [https://downloads.haskell.org/~ghc/7.8.3/docs/html/users_guide/pragmas.html
 users guide]:
 > "A file-header pragma must precede the module keyword in the file."
 > "The file-header pragmas are: {-# LANGUAGE #-}, {-# OPTIONS_GHC #-}, and
 {-# INCLUDE #-}."

 So the scope of this ticket should in my opinion be: when any file-header
 pragma (not only an unsupported language pragma)  is used after the module
 keyword, ghc should show a warning.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8015#comment:1>
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