panic: Kinds don't match in type application

In the test !CoTest3(normal) from the testsuite, I get

Compile failed (status 256) errors were:
*** Core Lint Errors: in result of Simplifier mode 0 [final], iteration 1 out of 4 ***
<no location info>:
    In the expression: (a_sfH
                        `cast` ((trans
                                   (trans
                                      s1_aeP
         <awfully long expression goes on and on>
                              GHC.Types.Int)
    Kinds don't match in type application:
    Type variable:
        co_wild_Xe :: trans
                        (trans
                           s1_aeP
             <awfully long type expression continues>
                        s2_aeQ
                        ~
                      GHC.Types.Int
    Arg type:ghc-stage2: panic! (the 'impossible' happened)
  (GHC version 6.12.1 for i386-unknown-linux):
	No match in record selector tyConKind

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

It seems to be the same expression as in http://darcs.haskell.org/buildbot/all/builders/x86%20Windows%20stable%20fast/builds/4253/steps/runtestsuite/logs/unexpected

Trac metadata

Trac field	Value
Version	6.12.1
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler
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