From 2d815d1f4a724875a6c724b5fd320967ee6219ba Mon Sep 17 00:00:00 2001
From: "simonpj@microsoft.com" <unknown>
Date: Fri, 5 Dec 2008 10:10:22 +0000
Subject: [PATCH] Add no-op case for addIdSpecialisations (very minor
 optimisation)

---
 compiler/specialise/Rules.lhs |    2 ++
 1 file changed, 2 insertions(+)

diff --git a/compiler/specialise/Rules.lhs b/compiler/specialise/Rules.lhs
index 39a9f05..51dc435 100644
--- a/compiler/specialise/Rules.lhs
+++ b/compiler/specialise/Rules.lhs
@@ -189,6 +189,8 @@ addSpecInfo (SpecInfo rs1 fvs1) (SpecInfo rs2 fvs2)
   = SpecInfo (rs1 ++ rs2) (fvs1 `unionVarSet` fvs2)
 
 addIdSpecialisations :: Id -> [CoreRule] -> Id
+addIdSpecialisations id []
+  = id
 addIdSpecialisations id rules
   = setIdSpecialisation id $
     extendSpecInfo (idSpecialisation id) rules
-- 
1.7.10.4