re PR libstdc++/17012 ([DR 526] std::list's function, remove, looks like it is…

re PR libstdc++/17012 ([DR 526] std::list's function, remove, looks like it is reading memory that has been freed.)

2007-02-08  Howard Hinnant  <hhinnant@apple.com>

	PR libstdc++/17012
	* include/bits/list.tcc (list<>::remove): Take care of
	&*__first == &__value.
	* docs/html/ext/howto.html: Add an entry for DR 526.

From-SVN: r121735

libstdc++-v3/ChangeLog

+2007-02-08  Howard Hinnant  <hhinnant@apple.com>
+
+	PR libstdc++/17012
+	* include/bits/list.tcc (list<>::remove): Take care of
+	&*__first == &__value.
+	* docs/html/ext/howto.html: Add an entry for DR 526.
+
 2007-02-07  Jakub Jelinek  <jakub@redhat.com>
 
 	PR libgomp/28468

libstdc++-v3/docs/html/ext/howto.html

@@ -586,6 +586,13 @@
     <dd>Construct a <code>linear_congruential</code> engine and seed with it.
     </dd>
 
+    <dt><a href="lwg-active.html#526">526</a>:
+        <em>Is it undefined if a function in the standard changes in
+	    parameters?</em>
+    </dt>
+    <dd>Use &amp;value.
+    </dd>
+
     <dt><a href="lwg-defects.html#538">538</a>:
         <em>241 again: Does unique_copy() require CopyConstructible
 	    and Assignable?</em>

libstdc++-v3/include/bits/list.tcc

 // List implementation (out of line) -*- C++ -*-
 
-// Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006
+// Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007
 // Free Software Foundation, Inc.
 //
 // This file is part of the GNU ISO C++ Library.  This library is free
@@ -176,14 +176,25 @@ _GLIBCXX_BEGIN_NESTED_NAMESPACE(std, _GLIBCXX_STD)
     {
       iterator __first = begin();
       iterator __last = end();
+      iterator __extra = __last;
       while (__first != __last)
 	{
 	  iterator __next = __first;
 	  ++__next;
 	  if (*__first == __value)
-	    _M_erase(__first);
+	    {
+	      // _GLIBCXX_RESOLVE_LIB_DEFECTS
+	      // 526. Is it undefined if a function in the standard changes
+	      // in parameters?
+	      if (&*__first != &__value)
+		_M_erase(__first);
+	      else
+		__extra = __first;
+	    }
 	  __first = __next;
 	}
+      if (__extra != __last)
+	_M_erase(__extra);
     }
 
   template<typename _Tp, typename _Alloc>