[GHC] #3064: Very long compile times with type functions

[GHC]

#3064: Very long compile times with type functions
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        Reporter:  simonpj           |                   Owner:
            Type:  bug               |                  Status:  closed
        Priority:  low               |               Milestone:  7.12.1
       Component:  Compiler (Type    |                 Version:  6.10.1
  checker)                           |                Keywords:
      Resolution:  fixed             |            Architecture:
Operating System:  Unknown/Multiple  |  Unknown/Multiple
 Type of failure:  Compile-time      |               Test Case:
  performance bug                    |  perf/compiler/T3064
      Blocked By:                    |                Blocking:
 Related Tickets:                    |  Differential Revisions:
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Comment (by goldfire):

 Good points in comment:21. I'm especially swayed by the ease with which
 this regression can be avoided, whereas previous problems were not.

 I do think, once a decision is made regarding 7.10 vs 7.12, a release note
 should be added. And, if possible, an error message that includes a note
 whenever the strictly-decreasing-superclass criterion bites would also be
 great.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/3064#comment:22>
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