[GHC] #9077: Forcing the type to be IO {} instead of IO() causes a "panic! The impossible has happened" output.

[GHC]

#9077: Forcing the type to be IO {} instead of IO() causes a "panic! The
impossible has happened" output.
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              Reporter:  Westycoot   |            Owner:
                  Type:  bug         |           Status:  closed
              Priority:  normal      |        Milestone:
             Component:  Compiler    |          Version:  7.8.2
            Resolution:  worksforme  |         Keywords:
      Operating System:              |     Architecture:  x86
  Unknown/Multiple                   |       Difficulty:  Unknown
       Type of failure:  Compile-    |       Blocked By:
  time performance bug               |  Related Tickets:
             Test Case:              |
  rename/should_fail/T9077           |
              Blocking:              |
Differential Revisions:              |
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Comment (by Simon Peyton Jones <simonpj@…>):

 In [changeset:"13817f06bc8065476711451307039387e3e34576/ghc"]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="13817f06bc8065476711451307039387e3e34576"
 Test Trac #9077
 }}}

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9077#comment:4>
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