[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:
              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 jstolarek):

 I think it is a good idea to also add a comment that motivates to remove
 tabs when doing some major changes to the file. I think we could just
 reuse the comment used in GHC source code:

 {{{
 {-# OPTIONS_GHC -fno-warn-tabs #-}
 -- The above warning supression flag is a temporary kludge.
 -- While working on this module you are encouraged to remove it and
 -- detab the module (please do the detabbing in a separate patch). See
 --
 http://ghc.haskell.org/trac/ghc/wiki/Commentary/CodingStyle#TabsvsSpaces
 -- for details
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9230#comment:9>
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