diff --git a/ghc/compiler/rename/RnExpr.lhs b/ghc/compiler/rename/RnExpr.lhs
index 5102f544a1fc4de98a2653dfae7e7c8c64dbb591..e1125a91f94e863ba27ce8ea32af0fa3b2e097a2 100644
--- a/ghc/compiler/rename/RnExpr.lhs
+++ b/ghc/compiler/rename/RnExpr.lhs
@@ -487,7 +487,7 @@ horner b i | abs q <= 1 = if r == 0 || r == i then mkInt i else mkInt r `plus` m
          mkInt i  = HsLit (HsInt i)
          plus     = mkOp "+"
          times    = mkOp "*"
-         mkOp op = \x y -> OpApp x (HsVar (mkSrcUnqual varName (_PK_ op))) (panic "fixity") y
+         mkOp op  = \x y -> HsPar (OpApp x (HsVar (mkSrcUnqual varName (_PK_ op))) (panic "fixity") y)
 \end{code}
 
 %************************************************************************