[v3] libstdc++/53515

[Paolo Carlini]

Hi,

tested x86_64-linux, committed to mainline.

Paolo.

///////////////////////

2012-09-26  Akira Takahashi  <faithandbr...@gmail.com>

        PR libstdc++/53515
        * include/bits/stl_iterator_base_funcs.h (__advance(_InputIterator&,
        _Distance, input_iterator_tag)): Add _GLIBCXX_DEBUG_ASSERT(__n >= 0).

Index: include/bits/stl_iterator_base_funcs.h
===================================================================
--- include/bits/stl_iterator_base_funcs.h      (revision 191781)
+++ include/bits/stl_iterator_base_funcs.h      (working copy)
@@ -1,7 +1,6 @@
 // Functions used by iterators -*- C++ -*-
 
-// Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
-// Free Software Foundation, Inc.
+// Copyright (C) 2001-2012 Free Software Foundation, Inc.
 //
 // This file is part of the GNU ISO C++ Library.  This library is free
 // software; you can redistribute it and/or modify it under the
@@ -63,6 +62,7 @@
 #pragma GCC system_header
 
 #include <bits/concept_check.h>
+#include <debug/debug.h>
 
 namespace std _GLIBCXX_VISIBILITY(default)
 {
@@ -124,6 +124,7 @@
     {
       // concept requirements
       __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>)
+      _GLIBCXX_DEBUG_ASSERT(__n >= 0);
       while (__n--)
        ++__i;
     }