[GHC] #5622: Out of memory in such a simple case

[GHC]

#5622: Out of memory in such a simple case
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        Reporter:  quux              |                Owner:  (none)
            Type:  bug               |               Status:  closed
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  7.2.1
      Resolution:  invalid           |             Keywords:
Operating System:  Windows           |         Architecture:  x86_64
 Type of failure:  Compile-time      |  (amd64)
  crash                              |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by kirelagin):

 For all those people from the future who’ll try to figure out what is
 going on here, a small clarification: the issue is not with type-inference
 itself, you can easily use `:t` in GHCi and it will infer the type
 instantly.

 The problem is that in Core type applications are spelled out explicitly,
 so the ''terms'' end up being exponentially large.

 {{{
 foo4 :: forall a_alK. a_alK -> a_alK
 [GblId, Str=DmdType]
 foo4 =
   \ (@ a_am0) ->
     id
       @ (((a_am0 -> a_am0) -> a_am0 -> a_am0)
          -> (a_am0 -> a_am0) -> a_am0 -> a_am0)
       (id @ ((a_am0 -> a_am0) -> a_am0 -> a_am0))
       (id @ (a_am0 -> a_am0))
       (id @ a_am0)
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/5622#comment:4>
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