From 7edaba2692e2c3c47e24d5746b5cf16233bca6e5 Mon Sep 17 00:00:00 2001
From: "simonpj@microsoft.com" <unknown>
Date: Sun, 22 Apr 2007 21:19:37 +0000
Subject: [PATCH] Warning police

---
 compiler/typecheck/TcDeriv.lhs |    2 ++
 1 file changed, 2 insertions(+)

diff --git a/compiler/typecheck/TcDeriv.lhs b/compiler/typecheck/TcDeriv.lhs
index 7a584cd..58db618 100644
--- a/compiler/typecheck/TcDeriv.lhs
+++ b/compiler/typecheck/TcDeriv.lhs
@@ -381,6 +381,8 @@ deriveTyData (deriv_pred, L loc decl@(TyData { tcdLName = L _ tycon_name,
 		-- The "deriv_pred" is a LHsType to take account of the fact that for
 		-- newtype deriving we allow deriving (forall a. C [a]).
 	; mkEqnHelp DerivOrigin (tvs++deriv_tvs) cls cls_tys tc_app } }
+deriveTyData (deriv_pred, other_decl)
+  = panic "derivTyData"	-- Caller ensures that only TyData can happen
 
 ------------------------------------------------------------------
 mkEqnHelp orig tvs cls cls_tys tc_app
-- 
1.7.10.4