Pattern Synonyms using other synonyms causes ghc panic

Here's a (somewhat) minimal example:

{-# LANGUAGE PatternSynonyms #-}

data Some = Thing Int Int


pattern A x = Thing x 0
pattern B x = Thing x 1
pattern C x = Thing x 2

pattern D = C 3

And here's what happened when I tried to load this into ghci:

*Main> :l ghc_bug.hs
[1 of 1] Compiling Main             ( ghc_bug.hs, interpreted )
ghc: panic! (the 'impossible' happened)
  (GHC version 8.0.1 for x86_64-unknown-linux):
        kindPrimRep.go rep_a3fP

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

Trac metadata

Trac field	Value
Version	8.0.1
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler
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