re PR libstdc++/56085 (Unsafe negation in C++03 pow(complex,int))

2013-01-24  Paolo Carlini  <paolo.carlini@oracle.com>

	PR libstdc++/56085
	* include/std/complex (pow(const complex<>&, int)): Avoid __n
	signed overflow.

From-SVN: r195421

libstdc++-v3/ChangeLog

+2013-01-24  Paolo Carlini  <paolo.carlini@oracle.com>
+
+	PR libstdc++/56085
+	* include/std/complex (pow(const complex<>&, int)): Avoid __n
+	signed overflow.
+
 2013-01-22  Jakub Jelinek  <jakub@redhat.com>
 
 	* testsuite/29_atomics/atomic_flag/test_and_set/explicit-hle.cc:

libstdc++-v3/include/std/complex

 // The template and inlines for the -*- C++ -*- complex number classes.
 
-// Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
-// 2006, 2007, 2008, 2009, 2010, 2011
-// Free Software Foundation, Inc.
+// Copyright (C) 1997-2013 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
@@ -978,7 +976,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     pow(const complex<_Tp>& __z, int __n)
     {
       return __n < 0
-        ? complex<_Tp>(1) / std::__complex_pow_unsigned(__z, -__n)
+	? complex<_Tp>(1) / std::__complex_pow_unsigned(__z, -(unsigned)__n)
         : std::__complex_pow_unsigned(__z, __n);
     }
 #endif