PolyKinds03 and PolyKinds13 fail an ASSERT

With a slow validate build on OSX, PolyKinds03 fails:

cd . && '/Users/ian/ghc/7.4-branch/val64/inplace/bin/ghc-stage2' -fforce-recomp -dcore-lint -dcmm-lint -dno-debug-output -no-user-package-conf -rtsopts  -fno-ghci-history -c PolyKinds03.hs    >PolyKinds03.comp.stderr 2>&1
Compile failed (status 256) errors were:
ghc-stage2: panic! (the 'impossible' happened)
  (GHC version 7.4.0.20120126 for x86_64-apple-darwin):
        ASSERT failed! file compiler/types/Kind.lhs line 254
ghc-prim:GHC.Prim.BOX{(w) tc 347} ghc-prim:GHC.Prim.ArgKind{(w) tc 34p}

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

PolyKinds13 fails similarly.

Trac metadata

Trac field	Value
Version	7.4.1-rc2
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler
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