[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:  Phab:D255   |
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Comment (by mlen):

 Sorry, I didn't mean to confuse anyone. I should've added the link to
 phabricator as soon as I pushed to it, I guess.

 Replying to [comment:18 thoughtpolice]:
 > I need to do a review on the testsuite changes in the patch, but it
 seems fine at a quick glance (I mostly wonder about the changes to the
 testsuite driver).

 The purpose of changes in test driver was to make it possible to remove
 compile time flag. Test T9230 wouldn't make any sense if it was run with
 `-fno-warn-tabs`, so I had to remove that flag for this test.

 I hope it is still possible for this patch to be released with GHC 7.10.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9230#comment:21>
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