[GHC] #10359: Tuple constraint synonym led to asymptotic performance lossage

[GHC]

#10359: Tuple constraint synonym led to asymptotic performance lossage
-------------------------------------+-------------------------------------
        Reporter:  axch              |                   Owner:
            Type:  bug               |                  Status:  closed
        Priority:  normal            |               Milestone:
       Component:  Compiler          |                 Version:  7.6.3
      Resolution:  fixed             |                Keywords:
Operating System:  Linux             |            Architecture:  x86_64
 Type of failure:  Runtime           |  (amd64)
  performance bug                    |               Test Case:
      Blocked By:                    |  perf/should_run/T10359
 Related Tickets:                    |                Blocking:
                                     |  Differential Revisions:
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Comment (by Austin Seipp <austin@…>):

 In [changeset:"3cf8ecdc70cb295a2b9606080a1c7b5fa8eb16f4/ghc"]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="3cf8ecdc70cb295a2b9606080a1c7b5fa8eb16f4"
 Revert multiple commits

 This reverts multiple commits from Simon:

   - 04a484eafc9eb9f8774b4bdd41a5dc6c9f640daf Test Trac #10359
   - a9ccd37add8315e061c02e5bf26c08f05fad9ac9 Test Trac #10403
   - c0aae6f699cbd222d826d0b8d78d6cb3f682079e Test Trac #10248
   - eb6ca851f553262efe0824b8dcbe64952de4963d Make the "matchable-given"
 check happen first
   - ca173aa30467a0b1023682d573fcd94244d85c50 Add a case to checkValidTyCon
   - 51cbad15f86fca1d1b0e777199eb1079a1b64d74 Update haddock submodule
   - 6e1174da5b8e0b296f5bfc8b39904300d04eb5b7 Separate transCloVarSet from
 fixVarSet
   - a8493e03b89f3b3bfcdb6005795de050501f5c29 Fix imports in HscMain
 (stage2)
   - a154944bf07b2e13175519bafebd5a03926bf105 Two wibbles to fix the build
   - 5910a1bc8142b4e56a19abea104263d7bb5c5d3f Change in capitalisation of
 error msg
   - 130e93aab220bdf14d08028771f83df210da340b Refactor tuple constraints
   - 8da785d59f5989b9a9df06386d5bd13f65435bc0 Delete commented-out line

 These break the build by causing Haddock to fail mysteriously when
 trying to examine GHC.Prim it seems.
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10359#comment:9>
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