PR56193 - Wrong test operator for basic_ios in C++11.

From-SVN: r195849

libstdc++-v3/ChangeLog

+2013-02-06  Edward Smith-Rowland  <3dw4rd@verizon.net>
+
+	* include/bits/basic_ios.h: Replace operator void*() const
+	with explicit operator bool() const in C++11 and greater.
+	* testsuite/27_io/basic_ios/pr56193.cc: New file.
+
 2013-02-04  Dodji Seketeli  <dodji@redhat.com>
 
 	Add missing explicit instantiation for std::lower_bound template

libstdc++-v3/include/bits/basic_ios.h

@@ -112,8 +112,13 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
        *  This allows you to write constructs such as
        *  <code>if (!a_stream) ...</code> and <code>while (a_stream) ...</code>
       */
+#if __cplusplus >= 201103L
+      explicit operator bool() const
+      { return !this->fail(); }
+#else
       operator void*() const
       { return this->fail() ? 0 : const_cast<basic_ios*>(this); }
+#endif
 
       bool
       operator!() const

libstdc++-v3/testsuite/27_io/basic_ios/pr56193.cc

+// { dg-do compile }
+// { dg-options "-std=gnu++11" }
+// Copyright (C) 2013 Free Software Foundation, Inc.
+
+#include <iostream>
+
+// PR libstdc++/56193
+
+int
+test01()
+{
+  std::cout << std::cout; // { dg-error "cannot bind" }
+}
+
+// { dg-error "initializing argument" "" { target *-*-* } 602 }