From: simonpj <unknown>
Date: Wed, 27 Jul 2005 11:55:43 +0000 (+0000)
Subject: [project @ 2005-07-27 11:55:43 by simonpj]
X-Git-Tag: Initial_conversion_from_CVS_complete~299
X-Git-Url: http://git.megacz.com/?a=commitdiff_plain;h=03aa4b6dfb67cc20b94b5fb19c8e8c5958603ea6;p=ghc-hetmet.git

[project @ 2005-07-27 11:55:43 by simonpj]
Bogon in RULE desguaring
---

diff --git a/ghc/compiler/deSugar/DsBinds.lhs b/ghc/compiler/deSugar/DsBinds.lhs
index 87fda8e..5be1774 100644
--- a/ghc/compiler/deSugar/DsBinds.lhs
+++ b/ghc/compiler/deSugar/DsBinds.lhs
@@ -266,11 +266,13 @@ decomposeRuleLhs all_bndrs lhs
 
 	-- Substitute dicts in the LHS args, so that there 
 	-- aren't any lets getting in the way
+	-- Note that we substitute the function too; we might have this as
+	-- a LHS:	let f71 = M.f Int in f71
     go env (Let (NonRec dict rhs) body) 
 	= go (extendVarEnv env dict (simpleSubst env rhs)) body
     go env body 
-	= case collectArgs body of
-	    (Var fn, args) -> Just (all_bndrs', fn, map (simpleSubst env) args)
+	= case collectArgs (simpleSubst env body) of
+	    (Var fn, args) -> Just (all_bndrs', fn, args)
 	    other 	   -> Nothing
 
 simpleSubst :: IdEnv CoreExpr -> CoreExpr -> CoreExpr