From 54cbdfde8ff2073adebea3199efffa79367571ef Mon Sep 17 00:00:00 2001
From: lewie <unknown>
Date: Tue, 10 Apr 2001 22:34:47 +0000
Subject: [PATCH] [project @ 2001-04-10 22:34:47 by lewie] Don't use
 foldr/build if we've got a parallel list comp.  We'd need
 to have/generate a family of functions foldr{2,3,...} to do
 anything nicer here.

---
 ghc/compiler/deSugar/DsListComp.lhs |    6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/ghc/compiler/deSugar/DsListComp.lhs b/ghc/compiler/deSugar/DsListComp.lhs
index 431fb93..337535d 100644
--- a/ghc/compiler/deSugar/DsListComp.lhs
+++ b/ghc/compiler/deSugar/DsListComp.lhs
@@ -44,7 +44,8 @@ dsListComp :: [TypecheckedStmt]
 	   -> DsM CoreExpr
 
 dsListComp quals elt_ty
-  | not opt_FoldrBuildOn 		 -- Be boring
+  |  not opt_FoldrBuildOn 		 -- Be boring
+  || isParallelComp quals
   = deListComp quals (mkNilExpr elt_ty)
 
   | otherwise				 -- foldr/build lives!
@@ -58,6 +59,9 @@ dsListComp quals elt_ty
     dsLookupGlobalValue buildName	`thenDs` \ build_id ->
     returnDs (Var build_id `App` Type elt_ty 
 			   `App` mkLams [n_tyvar, c, n] result)
+
+  where isParallelComp (ParStmtOut bndrstmtss : _) = True
+	isParallelComp _                           = False
 \end{code}
 
 %************************************************************************
-- 
1.7.10.4