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Panic in conflictInstErr when branched type family instances conflict

This code causes the panic:

{-# LANGUAGE TypeFamilies #-}

type family F a

type instance where
  F Int = Int
  F Bool = Bool

type instance where
  F Int = Char
  F Double = Double

Here is the output:

ghc: panic! (the 'impossible' happened)
  (GHC version 7.7.20121221 for x86_64-apple-darwin):
	conflictInstErr
<<details unavailable>>

Fix on the way...

Trac metadata
Trac field Value
Version 7.7
Type Bug
TypeOfFailure OtherFailure
Priority normal
Resolution Unresolved
Component Compiler
Test case
Differential revisions
BlockedBy
Related
Blocking
CC
Operating system
Architecture
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