X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=blobdiff_plain;f=compiler%2FdeSugar%2FDsBinds.lhs;fp=compiler%2FdeSugar%2FDsBinds.lhs;h=815c0d1cfb2222319b65e8e49b185cedd4b1ba26;hp=57c74825960872c104c57959e481ae48d6e58b33;hb=0aebf9c6b0de711b7eefa8c4cdd56d9328886697;hpb=e8a42ae2991013f586cb0606fcbd70d9b4c41d6f

diff --git a/compiler/deSugar/DsBinds.lhs b/compiler/deSugar/DsBinds.lhs
index 57c7482..815c0d1 100644
--- a/compiler/deSugar/DsBinds.lhs
+++ b/compiler/deSugar/DsBinds.lhs
@@ -526,13 +526,14 @@ dsSpec mb_poly_rhs (L loc (SpecPrag poly_id spec_co spec_inl))
   where
     is_local_id = isJust mb_poly_rhs
     poly_rhs | Just rhs <-  mb_poly_rhs
-             = rhs
-             | Just unfolding <- maybeUnfoldingTemplate (idUnfolding poly_id)
-             = unfolding
+             = rhs  	    -- Local Id; this is its rhs
+             | Just unfolding <- maybeUnfoldingTemplate (realIdUnfolding poly_id)
+             = unfolding    -- Imported Id; this is its unfolding
+	       		    -- Use realIdUnfolding so we get the unfolding 
+			    -- even when it is a loop breaker. 
+			    -- We want to specialise recursive functions!
              | otherwise = pprPanic "dsImpSpecs" (ppr poly_id)
-	-- In the Nothing case the specialisation is for an imported Id
-	-- whose unfolding gives the RHS to be specialised
-        -- The type checker has checked that it has an unfolding
+	                    -- The type checker has checked that it *has* an unfolding
 
 specUnfolding :: (CoreExpr -> CoreExpr) -> Type 
               -> Unfolding -> DsM (Unfolding, OrdList (Id,CoreExpr))