TcTyFuns.uMeta: normalisation shouldn't allow x ~ x

pizza@extracheese:~/proj/truegraph$ ghci stats.hs 
GHCi, version 6.10.0.20081007: http://www.haskell.org/ghc/  :? for help
Loading package ghc-prim ... linking ... done.
Loading package integer ... linking ... done.
Loading package base ... linking ... done.
[1 of 1] Compiling Main             ( stats.hs, interpreted )
ghc: panic! (the 'impossible' happened)
  (GHC version 6.10.0.20081007 for i386-unknown-linux):
        TcTyFuns.uMeta: normalisation shouldn't allow x ~ x

Please report this as a GHC bug:  http://www.haskell.org/ghc/reportabug

> 

where stats.hs is:

mean :: (Num b) => [a] -> (a -> b) -> b
mean set f = 
  let total = sum $ map f set 
      mean' = total / fromIntegral $ length set 
  in mean'

NOTE that i'm not even sure if this code is correct or makes sense, i'm in the middle of growing it.

Trac metadata

Trac field	Value
Version	6.10.1
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler
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