From 0c677ddd4cab7b88b5373f573bcaf752d7322007 Mon Sep 17 00:00:00 2001
From: Michael Stevens <mail@michael-stevens.de>
Date: Tue, 21 Sep 2004 22:27:38 +0000
Subject: [PATCH] fix slice compose negative start check

---
 include/boost/numeric/ublas/storage.hpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/include/boost/numeric/ublas/storage.hpp b/include/boost/numeric/ublas/storage.hpp
index 84f9b8c8..b8cd0127 100644
--- a/include/boost/numeric/ublas/storage.hpp
+++ b/include/boost/numeric/ublas/storage.hpp
@@ -1133,12 +1133,12 @@ namespace boost { namespace numeric { namespace ublas {
         // Composition
         BOOST_UBLAS_INLINE
         basic_slice compose (const basic_range<size_type, difference_type> &r) const {
-            BOOST_UBLAS_CHECK (start_ >= stride_ * r.start (), bad_index ());
+            BOOST_UBLAS_CHECK (stride_ >=0 || start_ >= -stride_ * r.start(), bad_index ());
             return basic_slice (start_ + stride_ * r.start (), stride_, r.size ());
         }
         BOOST_UBLAS_INLINE
         basic_slice compose (const basic_slice &s) const {
-            BOOST_UBLAS_CHECK (start_ >= stride_ * s.start_, bad_index ());
+            BOOST_UBLAS_CHECK (stride_ >=0 || start_ >= -stride_ * s.start_, bad_index ());
             return basic_slice (start_ + stride_ * s.start_, stride_ * s.stride_, s.size_);
         }