-#ifdef DEBUG
- ; traceTc (text "tcGen" <+> vcat [text "extra_tvs" <+> ppr extra_tvs,
- text "expected_ty" <+> ppr expected_ty,
- text "inst ty" <+> ppr tvs' <+> ppr theta' <+> ppr rho',
- text "free_tvs" <+> ppr free_tvs])
-#endif
+ ; when debugIsOn $
+ traceTc (text "tcGen" <+> vcat [
+ text "extra_tvs" <+> ppr extra_tvs,
+ text "expected_ty" <+> ppr expected_ty,
+ text "inst ty" <+> ppr tvs' <+> ppr theta'
+ <+> ppr rho',
+ text "free_tvs" <+> ppr free_tvs])