Make SpecConstr work again

In a typo I'd written env instead of env', and as a result RULES are
practically guaranteed not to work in a recursive group.  This pretty
much kills SpecConstr in its tracks!

Well done Kenny Lu for spotting this.  The fix is easy.

Merge into 6.8 please.

diff --git a/compiler/simplCore/Simplify.lhs b/compiler/simplCore/Simplify.lhs
index dbad116..a27aa47 100644 (file)
--- a/compiler/simplCore/Simplify.lhs
+++ b/compiler/simplCore/Simplify.lhs
@@ -264,7 +264,7 @@ simplRecBind env top_lvl pairs
   where
     add_rules :: SimplEnv -> (InBndr,InExpr) -> (SimplEnv, (InBndr, OutBndr, InExpr))
        -- Add the (substituted) rules to the binder
-    add_rules env (bndr, rhs) = (env, (bndr, bndr', rhs))
+    add_rules env (bndr, rhs) = (env', (bndr, bndr', rhs))
        where
          (env', bndr') = addBndrRules env bndr (lookupRecBndr env bndr)