[GHC] #14052: Significant GHCi speed regression with :module and `let` in GHC 8.2.1

[GHC]

#14052: Significant GHCi speed regression with :module and `let` in GHC 8.2.1
-------------------------------------+-------------------------------------
        Reporter:  RyanGlScott       |                Owner:  osa1
            Type:  bug               |               Status:  patch
        Priority:  high              |            Milestone:  8.4.2
       Component:  GHCi              |              Version:  8.2.1-rc2
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Runtime           |  Unknown/Multiple
  performance bug                    |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #11547            |  Differential Rev(s):  Phab:D4478
       Wiki Page:                    |
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Comment (by Ömer Sinan Ağacan <omeragacan@…>):

 In [changeset:"98c7749cd360293bee96034056e260d70224cef6/ghc" 98c7749/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="98c7749cd360293bee96034056e260d70224cef6"
 Revert "GHCi: Don't remove shadowed bindings from typechecker scope."

 This reverts commit 59d7ee53906b9cee7f279c1f9567af7b930f8636 and enables
 the test for #14052.

 (See #14052 for the discussion)

 Reviewers: bgamari

 Reviewed By: bgamari

 Subscribers: rwbarton, thomie, carter

 GHC Trac Issues: #14052

 Differential Revision: https://phabricator.haskell.org/D4478
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14052#comment:21>
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