match_co: needs more cases

Evan Laforge qdunkan at
Mon May 27 19:56:26 CEST 2013

I made some strictifying changes and started getting this msg from ghc:

match_co: needs more cases
    vector-{tc r46}
      (Sym <(vector-{tc r45})>)
      <main:Util.TimeVectorStorable.Sample{tc r4e} y{tv a4lK} [tv]>

It's not just TimeVectorStorable.Sample (which is indeed stored in
Data.Vectors), we also have some mysterious compiler-generated

match_co: needs more cases
    vector-{tc rQA}
      (Sym <(vector-{tc rQz})>)
      <a{tv a6IH} [tv]>

I assume this is harmless, but I didn't see any other references to
this error on the web or on the ghc trac so maybe it's new?

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