[GHC] #9711: Confusing errors when compiling text-1.2.0.0

[GHC]

#9711: Confusing errors when compiling text-1.2.0.0
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              Reporter:  asvyazin      |            Owner:
                  Type:  bug           |           Status:  new
              Priority:  normal        |        Milestone:
             Component:  Compiler      |          Version:  7.8.3
            Resolution:                |         Keywords:
      Operating System:  MacOS X       |     Architecture:  x86_64 (amd64)
       Type of failure:  None/Unknown  |       Difficulty:  Unknown
             Test Case:                |       Blocked By:
              Blocking:                |  Related Tickets:
Differential Revisions:                |
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Comment (by rwbarton):

 This seems rather hard to believe. I get those exact errors (down to the
 column numbers) when I remove three spaces after `x == '\n'` (like in your
 last snippet) ''only''. Are you sure you haven't edited this file before
 trying to build it, possibly inserting tab characters in the process?

 I guess it's possible that the homebrew build is somehow faulty in a way
 that would cause this, but difficult to imagine.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9711#comment:1>
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