[GHC] #10341: hs-boot files can have bogus declarations if they're not exported

22 Apr 2015

      #10341: hs-boot files can have bogus declarations if they're not exported
-------------------------------------+-------------------------------------
              Reporter:  ezyang      |             Owner:
                  Type:  bug         |            Status:  new
              Priority:  low         |         Milestone:
             Component:  Compiler    |           Version:  7.11
  (Type checker)                     |  Operating System:  Unknown/Multiple
              Keywords:              |   Type of failure:  GHC accepts
          Architecture:              |  invalid program
  Unknown/Multiple                   |        Blocked By:
             Test Case:              |   Related Tickets:
              Blocking:              |
Differential Revisions:              |
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 Consider:

 {{{
 -- A.hs-boot
 module A(foo) where
 data A  = AC { bar :: Int } | CC
 -- B.hs
 module B where
 import {-# SOURCE #-} A
 -- A.hs
 module A(foo) where
 import B
 data A = AC { foo :: Int } | BC
 }}}

 GHC won't complain that `A` is incompatibly defined, since it's not
 exported.

 Seems relatively harmless though.

--
Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10341
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