From 10b33a266258e1075a45df445f5b8f71b7ea514d Mon Sep 17 00:00:00 2001
From: Marshall Clow <mclow.lists@gmail.com>
Date: Thu, 5 Mar 2015 16:07:37 +0000
Subject: [PATCH] Rework reverse_iterator::operator[] so as not to use the base
 iterators operator [], which can cause constness problems. Fixes PR17883

llvm-svn: 231375
---
 libcxx/include/iterator | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libcxx/include/iterator b/libcxx/include/iterator
index 04ff4c1..7f7e9ee1 100644
--- a/libcxx/include/iterator
+++ b/libcxx/include/iterator
@@ -575,7 +575,7 @@ public:
     _LIBCPP_INLINE_VISIBILITY reverse_iterator& operator-=(difference_type __n)
         {current += __n; return *this;}
     _LIBCPP_INLINE_VISIBILITY reference         operator[](difference_type __n) const
-        {return current[-__n-1];}
+        {return *(*this + __n);}
 };
 
 template <class _Iter1, class _Iter2>
-- 
2.7.4