[GHC] #13426: compile-time memory-usage regression for DynFlags between GHC 8.0 and GHC 8.2

[GHC]

#13426: compile-time memory-usage regression for DynFlags between GHC 8.0 and GHC
8.2
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        Reporter:  hvr               |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  high              |            Milestone:  8.2.1
       Component:  Compiler          |              Version:  8.1
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Compile-time      |  Unknown/Multiple
  performance bug                    |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D3399,
       Wiki Page:                    |  Phab:D3400, Phab:D3421
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Comment (by Ben Gamari <ben@…>):

 In [changeset:"59c925e88a1dcb98e62c2b5e0adaa299c3b15e44/ghc"
 59c925e8/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="59c925e88a1dcb98e62c2b5e0adaa299c3b15e44"
 More changes to fix a space leak in the simplifier (#13426)

 Part of e13419c55 was accidentally lost during a rebase. This commit
 adds the missing change, along with some more improvements
 regarding where we do and don't use `seqType`.

 Also include a comment about where the space leak showed up
 and a Note explaining the strategy being used here.

 Test Plan: harbormaster, plus local testing on DynFlags

 Reviewers: austin, bgamari

 Reviewed By: bgamari

 Subscribers: thomie

 Differential Revision: https://phabricator.haskell.org/D3421
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13426#comment:32>
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