foreign import from RTS into GHC source

Ian Lynagh ian at
Sat Jul 13 13:54:42 CEST 2013

On Wed, Jul 10, 2013 at 04:26:23PM -0500, Nicolas Frisby wrote:
> I'm adding a foreign import in a GHC module from the RTS. I'm using a CPP
> directive to avoid the import in the stage1 compiler, since the RTS
> function I need doesn't necessarily exist in that version of the RTS.
> EG Is there a preference to use Config.cStage instead of CPP and the STAGE
> symbol?

It's always better to not use CPP if possible, but in this instance
you'd presumably get a missing-symbol error, so CPP is necessary.

Ian Lynagh, Haskell Consultant
Well-Typed LLP,

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