This patch supports the quasi-quotation feature.  Here's the relevant
parts from the message in the big compiler patch:

  Fri Jan 18 14:55:03 GMT 2008  simonpj@microsoft.com
    * Add quasi-quotation, courtesy of Geoffrey Mainland
  
  This patch adds quasi-quotation, as described in
    "Nice to be Quoted: Quasiquoting for Haskell"
  	(Geoffrey Mainland, Haskell Workshop 2007)
  Implemented by Geoffrey and polished by Simon.

...snip...
  
  * There is an accompanying patch to the template-haskell library. This
    involves one interface change:
  	currentModule :: Q String
    is replaced by
  	location :: Q Loc
    where Loc is a data type defined in TH.Syntax thus:
        data Loc
          = Loc { loc_filename :: String
  	      , loc_package  :: String
  	      , loc_module   :: String
  	      , loc_start    :: CharPos
  	      , loc_end      :: CharPos }
  
        type CharPos = (Int, Int)	-- Line and character position
   
    So you get a lot more info from 'location' than from 'currentModule'.
    The location you get is the location of the splice.
    
    This works in Template Haskell too of course, and lets a TH program
    generate much better error messages.
  
  * There's also a new module in the template-haskell package called 
    Language.Haskell.TH.Quote, which contains support code for the
    quasi-quoting feature.