[GHC] #9230: Make -fwarn-tabs the default

[GHC]

#9230: Make -fwarn-tabs the default
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              Reporter:  dfeuer      |            Owner:  mlen
                  Type:  feature     |           Status:  new
  request                            |        Milestone:  7.10.1
              Priority:  normal      |          Version:  7.8.2
             Component:  Compiler    |         Keywords:
            Resolution:              |     Architecture:  Unknown/Multiple
      Operating System:              |       Difficulty:  Easy (less than 1
  Unknown/Multiple                   |  hour)
       Type of failure:              |       Blocked By:
  None/Unknown                       |  Related Tickets:
             Test Case:              |
              Blocking:              |
Differential Revisions:              |
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Comment (by dfeuer):

 Replying to [comment:16 simonpj]:
 > I'm sorry, I'm quite confused.  GHC already has a `-fwarn-tabs` flag,
 doesn't it?  There are two patches offered above, but I'm not clear what
 the purpose of either is. Maybe I have not ready through this ticket
 carefully enough.

 I don't understand that either. The essential ''problem'' we have is that
 we want `-fwarn-tabs` to be the default, but we have to find some way to
 get validation to pass when there are currently a lot of libraries in the
 GHC tree that have tabs but don't invoke `-fno-warn-tabs`.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9230#comment:17>
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