Can't compile happy + ghc with clang's CPP

On OS X MtnLion with Xcode 5:

Compiling GHC fails early on because the GenericTemate outputted by happy is syntactically invalid. It is invalid because of tabs inserted into the template that cause the functions to have syntax / indenting errors. I attempted to install happy to patch it, but happy will not compile either because of the tabs.

I think clang's CPP is inserting tabs into lines with > 8 spaces of indentation.

Also the comment lines in the template of this form are invalid for clang and cause it to fail.

# 5 comment

Trac metadata

Trac field	Value
Version	7.7
Type	Bug
TypeOfFailure	OtherFailure
Priority	highest
Resolution	Unresolved
Component	libraries (other)
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