[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:  patch
  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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Changes (by oerjan):

 * cc: oerjan (added)


Comment:

 This is an excellent change, but if it is to be newbie-friendly (which I
 ideally and egoistically define as "telling the user enough ''not'' to
 make yet another confused post on Stackoverflow"), maybe it could use a
 more explanatory error message than "Warning: Tab character"? Something
 like

  Tab characters aren't displayed portably. They can cause code to look
 correctly indented when it isn't, or vice versa, wildly varying dependent
 on the setup of the editor/browser/web site etc. used to view it.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9230#comment:24>
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