GHC panic when printing Unique

The following program causes panic:

    import UniqSupply
    main = mkSplitUniqSupply 'x' >>= print . uniqFromSupply

The error message is:

    ghcbug: ghcbug: panic! (the 'impossible' happened)
      (GHC version 6.10.1 for i386-apple-darwin):
	    Static flags have not been initialised!
            Please call GHC.newSession or GHC.parseStaticFlags early enough.

I have encountered this on an Apple !MacBook with GHC 6.10.1 and could reproduce it on a Linux PC with the same GHC version.

The module !UniqSupply comes from the ghc package which is hidden by default. So before compiling it (or running it in GHCi) type

    ghc-pkg expose ghc

in a shell.

Trac metadata

Trac field	Value
Version	6.10.1
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler
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GHC panic when printing Unique