I know in one application of mine, I had to add an explicit dependency for version 0.2.1.1 in order to get it to compile on GHC 6.12.3. That might be worth a shot. I'd heard that there was a fix in a later version for the issue I had, but if you're still getting failures, perhaps adding a version bound would help.

Then again, this may be related to people not running cabal update since the fix was released... so maybe the first answer is to suggest a cabal update.

On Apr 20, 2011 10:00 PM, "Michael Snoyman" <michael@snoyman.com> wrote:
> Hi Bas,
>
> I'm getting sporadic bug reports about base-unicode-symbols not
> compiling, which is preventing Yesod from compiling. I actually got
> the same error on GHC 6.12.1, and hacked around it by manually
> modifying the file to avoid the problematic CPP code. You can see a
> report in a Yesod book comment[1].
>
> I think I remember you saying this is a problem with the CPP in GHC
> 6.12.1. Do you know if there's any workaround?
>
> Thanks,
> Michael
>
> [1] http://www.yesodweb.com/book/migrate7to8#iy1
>
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