From: Bertram Felgenhauer <int-e@gmx.de>
Date: Wed, 21 Nov 2007 10:14:58 +0000 (+0000)
Subject: Data.List.sort: force elements from start to end.
X-Git-Tag: 2008-05-28~86
X-Git-Url: http://git.megacz.com/?a=commitdiff_plain;h=d7d871d674ee73c100ce5ab89ada80be2563ef79;p=ghc-base.git

Data.List.sort: force elements from start to end.
this prevents a stack overflow on  sort (take 10^6 [1..])
---

diff --git a/Data/List.hs b/Data/List.hs
index 1c52b50..19dbc7d 100644
--- a/Data/List.hs
+++ b/Data/List.hs
@@ -807,8 +807,8 @@ merge_pairs cmp [xs] = [xs]
 merge_pairs cmp (xs:ys:xss) = merge cmp xs ys : merge_pairs cmp xss
 
 merge :: (a -> a -> Ordering) -> [a] -> [a] -> [a]
-merge cmp xs [] = xs
 merge cmp [] ys = ys
+merge cmp xs [] = xs
 merge cmp (x:xs) (y:ys)
  = case x `cmp` y of
         GT -> y : merge cmp (x:xs)   ys