Regression: Pattern synonyms make GHCi 8.0.1 crash

This code:

{-# LANGUAGE PatternSynonyms #-}

data T = C

pattern P :: T
pattern P = C

pattern P' :: T
pattern P' = P

compiles fine with both GHC 7.10.3 and 8.0.1. However, if you try to load it into GHCi 8.0.1, it panics:

GHCi, version 8.0.1: http://www.haskell.org/ghc/  :? for help
Prelude> :l M.hs 
[1 of 1] Compiling Main             ( M.hs, interpreted )
ghc: panic! (the 'impossible' happened)
  (GHC version 8.0.1 for x86_64-unknown-linux):
	kindPrimRep.go rep_a18a

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

GHCi 7.10.3 does not crash, therefore it's a regression:

GHCi, version 7.10.3: http://www.haskell.org/ghc/  :? for help
Prelude> :l M.hs
[1 of 1] Compiling Main             ( M.hs, interpreted )
Ok, modules loaded: Main.
*Main> 

Trac metadata

Trac field	Value
Version	8.0.1
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	GHCi
Test case	https://gist.githubusercontent.com/int-index/17dfb68fd97f724aef2849d0defae0d6/raw/3dab71756bbafa197b93170310ccabfea8c92120/M.hs
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