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

5 May 2014

      #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:  new
        Priority:  normal                        |        Milestone:
       Component:  Compiler                      |          Version:  7.8.2
      Resolution:                                |         Keywords:
Operating System:  Unknown/Multiple              |     Architecture:  x86
 Type of failure:  Compile-time performance bug  |       Difficulty:
       Test Case:                                |  Unknown
        Blocking:                                |       Blocked By:
                                                 |  Related Tickets:
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Comment (by simonpj):

 I can't reproduce your crash. Can you show exact output and which compiler
 you are using?  Like this:
 {{{
 bash$ ghc -c T9077.hs

 T9077.hs:3:12: Record syntax is illegal here: {}

 bash$ ghc --version
 The Glorious Glasgow Haskell Compilation System, version 7.8.2

 bash$ cat T9077.hs
 module Main where

 main :: IO {}
 main = do
             e1 <- getLine
             e2 <- getLine
             print ((read e1) + (read e2))
 }}}
 I speculate that you are not using 7.8.2.

--
Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/9077#comment:1
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