X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2FcoreSyn%2FCoreSubst.lhs;h=a229b8c4e986496c41732ed22cd41bdb93d8d723;hb=6f66d02c9654fc037db0582857acdcc15e0fd1d3;hp=346f78f4876c867ce69816e56fa671c73d0f135a;hpb=aae915d6743e4c0986625f142df1fbc1384ff8df;p=ghc-hetmet.git

diff --git a/compiler/coreSyn/CoreSubst.lhs b/compiler/coreSyn/CoreSubst.lhs
index 346f78f..a229b8c 100644
--- a/compiler/coreSyn/CoreSubst.lhs
+++ b/compiler/coreSyn/CoreSubst.lhs
@@ -574,7 +574,9 @@ substUnfoldingSC subst unf 	 -- Short-cut version
   | otherwise          = substUnfolding subst unf
 
 substUnfolding subst (DFunUnfolding ar con args)
-  = DFunUnfolding ar con (map (substExpr (text "dfun-unf") subst) args)
+  = DFunUnfolding ar con (map subst_arg args)
+  where
+    subst_arg = fmap (substExpr (text "dfun-unf") subst)
 
 substUnfolding subst unf@(CoreUnfolding { uf_tmpl = tmpl, uf_src = src })
 	-- Retain an InlineRule!