-- c.f. TcSimplify.simplifyInfer
; zonked_forall_tvs <- zonkTcTyVarsAndFV forall_tvs
; gbl_tvs <- tcGetGlobalTyVars -- Already zonked
-- c.f. TcSimplify.simplifyInfer
; zonked_forall_tvs <- zonkTcTyVarsAndFV forall_tvs
; gbl_tvs <- tcGetGlobalTyVars -- Already zonked