[GHC] #11219: Implement fine-grained `-Werror=...` facility

[GHC]

#11219: Implement fine-grained `-Werror=...` facility
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        Reporter:  hvr               |                Owner:  quchen
            Type:  feature request   |               Status:  new
        Priority:  normal            |            Milestone:  8.2.1
       Component:  Compiler          |              Version:
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Incorrect         |  Unknown/Multiple
  warning at compile-time            |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #11796            |  Differential Rev(s):
       Wiki Page:  Design/Warnings   |
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Comment (by RyanGlScott):

 Wonderful!

 We usually review patches by using Phabricator, as it makes code review
 (and ultimately landing the patch) far simpler. Do you mind uploading your
 patch as a Diff by following the directions in this
 [https://ghc.haskell.org/trac/ghc/wiki/Phabricator wiki page]? I'd be
 happy to assist if you have any questions.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11219#comment:7>
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