From 4c7846e8a0336f71d5c16798e103980f83532c30 Mon Sep 17 00:00:00 2001
From: "andy@galois.com" <unknown>
Date: Tue, 1 May 2007 15:57:29 +0000
Subject: [PATCH] Stopping tick boxes for being removed round calls to error.

---
 compiler/simplCore/Simplify.lhs |    3 +++
 1 file changed, 3 insertions(+)

diff --git a/compiler/simplCore/Simplify.lhs b/compiler/simplCore/Simplify.lhs
index 25dc2ba..cab6460 100644
--- a/compiler/simplCore/Simplify.lhs
+++ b/compiler/simplCore/Simplify.lhs
@@ -1165,6 +1165,9 @@ rebuildCase env scrut case_bndr [(con,bndrs,rhs)] cont
 	-- The case binder is going to be evaluated later, 
 	-- and the scrutinee is a simple variable
     var_demanded_later (Var v) = isStrictDmd (idNewDemandInfo case_bndr)
+    		       	         && not (isTickBoxOp v)	
+				    -- ugly hack; covering this case is what 
+				    -- exprOkForSpeculation was intended for.
     var_demanded_later other   = False
 
 
-- 
1.7.10.4