GHC error in desugarer lookup

In GHC8-rc3, I'm getting:

    GHC error in desugarer lookup in CLaSH.Core.TyCon:
      Can't find interface-file declaration for variable $tcType
        Probable cause: bug in .hi-boot file, or inconsistent .hi file
        Use -ddump-if-trace to get an idea of which file caused the error
    ghc: panic! (the 'impossible' happened)
      (GHC version 8.0.0.20160411 for x86_64-unknown-linux):
        initDs IOEnv failure
    
    Please report this as a GHC bug:  http://www.haskell.org/ghc/reportabug

To reproduce (requires stack):

• git clone -b ghc8 https://github.com/clash-lang/clash-compiler.git
• cd clash-compiler
• git submodule update --init
• stack --stack-yaml=stack-ghc8.yaml build

The -ddump-if-trace of CLaSH.Core.TyCon can be found here: https://gist.github.com/christiaanb/1cd84e9941f6614321719e298cc12af0

I'm terribly sorry that the current instructions for reproducing the bug are to build my project and all its dependencies. I'm having a lot of trouble reducing the bug to a sensible/small test case, so any hints as to what might be the cause of this bug would be helpful.

Trac metadata

Trac field	Value
Version	8.0.1-rc3
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler
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