[GHC] #13594: Typechecker behavior w.r.t. BangPatterns and nested foralls has changed in 8.2

[GHC]

#13594: Typechecker behavior w.r.t. BangPatterns and nested foralls has changed in
8.2
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        Reporter:  RyanGlScott       |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  high              |            Milestone:  8.2.1
       Component:  Compiler (Type    |              Version:  8.2.1-rc2
  checker)                           |             Keywords:  BangPatterns,
      Resolution:                    |  RankNTypes
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  GHC rejects       |  Unknown/Multiple
  valid program                      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D3525
       Wiki Page:                    |
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Comment (by Ben Gamari <ben@…>):

 In [changeset:"3032ae81dd14c2eaefa9ecd8880dafa9bda104d9/ghc"
 3032ae81/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="3032ae81dd14c2eaefa9ecd8880dafa9bda104d9"
 Revert "Treat banged bindings as FunBinds"

 This partially reverts commit 372995364c52eef15066132d7d1ea8b6760034e6 as
 it
 doesn't actually fix #13594. Namely it does not revert the mkPrefixFunRhs
 refactoring since this is rather independent from the functional changes.

 Going to try again with a whole working patch
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13594#comment:15>
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