re PR libstdc++/25896 ([DR 526] hash_map::erase, unordered_map::erase fail if key is inside the table)

2007-02-23  Paolo Carlini  <pcarlini@suse.de>
	
	PR libstdc++/25896
	* include/tr1/hashtable (_Hashtable<>::erase(const key_type&)):
	Take care of &_M_extract((*__slot)->_M_v) == &__k.

	* testsuite/tr1/6_containers/unordered_map/erase/1.cc: New.
	* testsuite/tr1/6_containers/unordered_multimap/erase/1.cc: Likewise.
	* testsuite/tr1/6_containers/unordered_multiset/erase/1.cc: Likewise.
	* testsuite/tr1/6_containers/unordered_set/erase/1.cc: Likewise.

From-SVN: r122276

6 files changed, 556 insertions, 2 deletions

diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index eb27702..4a039e3 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,3 +1,14 @@
+2007-02-23  Paolo Carlini  <pcarlini@suse.de>
+	
+	PR libstdc++/25896
+	* include/tr1/hashtable (_Hashtable<>::erase(const key_type&)):
+	Take care of &_M_extract((*__slot)->_M_v) == &__k.
+
+	* testsuite/tr1/6_containers/unordered_map/erase/1.cc: New.
+	* testsuite/tr1/6_containers/unordered_multimap/erase/1.cc: Likewise.
+	* testsuite/tr1/6_containers/unordered_multiset/erase/1.cc: Likewise.
+	* testsuite/tr1/6_containers/unordered_set/erase/1.cc: Likewise.
+
 2007-02-23  Mark Mitchell  <mark@codesourcery.com>
 
 	* testsuite/27_io/ios_base/sync_with_stdio/1.cc: XFAIL for wrapped
diff --git a/libstdc++-v3/include/tr1/hashtable b/libstdc++-v3/include/tr1/hashtable
index 0d760ee..14742ab 100644
--- a/libstdc++-v3/include/tr1/hashtable
+++ b/libstdc++-v3/include/tr1/hashtable
@@ -1063,10 +1063,31 @@ _GLIBCXX_BEGIN_NAMESPACE(tr1)
       while (*__slot && !this->_M_compare(__k, __code, *__slot))
 	__slot = &((*__slot)->_M_next);
 
+      _Node** __saved_slot = 0;
       while (*__slot && this->_M_compare(__k, __code, *__slot))
 	{
-	  _Node* __p = *__slot;
-	  *__slot = __p->_M_next;
+	  // _GLIBCXX_RESOLVE_LIB_DEFECTS
+	  // 526. Is it undefined if a function in the standard changes
+	  // in parameters?
+	  if (&this->_M_extract((*__slot)->_M_v) != &__k)
+	    {
+              _Node* __p = *__slot;
+              *__slot = __p->_M_next;
+	      _M_deallocate_node(__p);
+	      --_M_element_count;
+	      ++__result;
+	    }
+	  else
+	    {
+	      __saved_slot = __slot;
+	      __slot = &((*__slot)->_M_next);
+	    }
+	}
+
+      if (__saved_slot)
+	{
+	  _Node* __p = *__saved_slot;
+	  *__saved_slot = __p->_M_next;
 	  _M_deallocate_node(__p);
 	  --_M_element_count;
 	  ++__result;
diff --git a/libstdc++-v3/testsuite/tr1/6_containers/unordered_map/erase/1.cc b/libstdc++-v3/testsuite/tr1/6_containers/unordered_map/erase/1.cc
new file mode 100644
index 0000000..139c906
--- /dev/null
+++ b/libstdc++-v3/testsuite/tr1/6_containers/unordered_map/erase/1.cc
@@ -0,0 +1,131 @@
+// 2007-02-22  Paolo Carlini  <pcarlini@suse.de> 
+//
+// Copyright (C) 2007 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
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 2, or (at your option)
+// any later version.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING.  If not, write to the Free
+// Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
+// USA.
+
+// 6.3.4.4  Class template unordered_map
+
+#include <tr1/unordered_map>
+#include <string>
+#include <testsuite_hooks.h>
+
+// In the occasion of libstdc++/25896
+void test01()
+{
+  bool test __attribute__((unused)) = true;
+  
+  typedef std::tr1::unordered_map<std::string, int> Map;
+  typedef Map::iterator       iterator;
+  typedef Map::const_iterator const_iterator;
+  typedef Map::value_type     value_type;
+
+  Map m1;
+
+  m1.insert(value_type("because to why", 1));
+  m1.insert(value_type("the stockholm syndrome", 2));
+  m1.insert(value_type("a cereous night", 3));
+  m1.insert(value_type("eeilo", 4));
+  m1.insert(value_type("protean", 5));
+  m1.insert(value_type("the way you are when", 6));
+  m1.insert(value_type("tillsammans", 7));
+  m1.insert(value_type("umbra/penumbra", 8));
+  m1.insert(value_type("belonging (no longer mix)", 9));
+  m1.insert(value_type("one line behind", 10));
+  VERIFY( m1.size() == 10 );
+
+  VERIFY( m1.erase("eeilo") == 1 );
+  VERIFY( m1.size() == 9 );
+  iterator it1 = m1.find("eeilo");
+  VERIFY( it1 == m1.end() );
+
+  VERIFY( m1.erase("tillsammans") == 1 );
+  VERIFY( m1.size() == 8 );
+  iterator it2 = m1.find("tillsammans");
+  VERIFY( it2 == m1.end() );
+
+  // Must work (see DR 526)
+  iterator it3 = m1.find("belonging (no longer mix)");
+  VERIFY( it3 != m1.end() );
+  VERIFY( m1.erase(it3->first) == 1 );
+  VERIFY( m1.size() == 7 );
+  it3 = m1.find("belonging (no longer mix)");
+  VERIFY( it3 == m1.end() );
+
+  VERIFY( !m1.erase("abra") );
+  VERIFY( m1.size() == 7 );
+
+  VERIFY( !m1.erase("eeilo") );
+  VERIFY( m1.size() == 7 );
+
+  VERIFY( m1.erase("because to why") == 1 );
+  VERIFY( m1.size() == 6 );
+  iterator it4 = m1.find("because to why");
+  VERIFY( it4 == m1.end() );
+
+  iterator it5 = m1.find("umbra/penumbra");
+  iterator it6 = m1.find("one line behind");
+  VERIFY( it5 != m1.end() );
+  VERIFY( it6 != m1.end() );
+
+  VERIFY( m1.find("the stockholm syndrome") != m1.end() );
+  VERIFY( m1.find("a cereous night") != m1.end() );
+  VERIFY( m1.find("the way you are when") != m1.end() );
+  VERIFY( m1.find("a cereous night") != m1.end() );
+
+  VERIFY( m1.erase(it5->first) == 1 );
+  VERIFY( m1.size() == 5 );
+  it5 = m1.find("umbra/penumbra");
+  VERIFY( it5 == m1.end() );
+
+  VERIFY( m1.erase(it6->first) == 1 );
+  VERIFY( m1.size() == 4 );
+  it6 = m1.find("one line behind");
+  VERIFY( it6 == m1.end() );
+
+  iterator it7 = m1.begin();
+  iterator it8 = it7;
+  ++it8;
+  iterator it9 = it8;
+  ++it9;
+
+  VERIFY( m1.erase(it8->first) == 1 );
+  VERIFY( m1.size() == 3 );
+  VERIFY( ++it7 == it9 );
+
+  iterator it10 = it9;
+  ++it10;
+  iterator it11 = it10;
+
+  VERIFY( m1.erase(it9->first) == 1 );
+  VERIFY( m1.size() == 2 );
+  VERIFY( ++it10 == m1.end() );
+
+  VERIFY( m1.erase(m1.begin()) != m1.end() );  
+  VERIFY( m1.size() == 1 );
+  VERIFY( m1.begin() == it11 );
+
+  VERIFY( m1.erase(m1.begin()->first) == 1 );  
+  VERIFY( m1.size() == 0 );
+  VERIFY( m1.begin() == m1.end() );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/tr1/6_containers/unordered_multimap/erase/1.cc b/libstdc++-v3/testsuite/tr1/6_containers/unordered_multimap/erase/1.cc
new file mode 100644
index 0000000..f060f4b
--- /dev/null
+++ b/libstdc++-v3/testsuite/tr1/6_containers/unordered_multimap/erase/1.cc
@@ -0,0 +1,131 @@
+// 2007-02-22  Paolo Carlini  <pcarlini@suse.de> 
+//
+// Copyright (C) 2007 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
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 2, or (at your option)
+// any later version.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING.  If not, write to the Free
+// Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
+// USA.
+
+// 6.3.4.6  Class template unordered_multimap
+
+#include <tr1/unordered_map>
+#include <string>
+#include <testsuite_hooks.h>
+
+// In the occasion of libstdc++/25896
+void test01()
+{
+  bool test __attribute__((unused)) = true;
+  
+  typedef std::tr1::unordered_multimap<std::string, int> Mmap;
+  typedef Mmap::iterator       iterator;
+  typedef Mmap::const_iterator const_iterator;
+  typedef Mmap::value_type     value_type;
+
+  Mmap mm1;
+
+  mm1.insert(value_type("because to why", 1));
+  mm1.insert(value_type("the stockholm syndrome", 2));
+  mm1.insert(value_type("a cereous night", 3));
+  mm1.insert(value_type("eeilo", 4));
+  mm1.insert(value_type("protean", 5));
+  mm1.insert(value_type("the way you are when", 6));
+  mm1.insert(value_type("tillsammans", 7));
+  mm1.insert(value_type("umbra/penumbra", 8));
+  mm1.insert(value_type("belonging (no longer mix)", 9));
+  mm1.insert(value_type("one line behind", 10));
+  VERIFY( mm1.size() == 10 );
+
+  VERIFY( mm1.erase("eeilo") == 1 );
+  VERIFY( mm1.size() == 9 );
+  iterator it1 = mm1.find("eeilo");
+  VERIFY( it1 == mm1.end() );
+
+  VERIFY( mm1.erase("tillsammans") == 1 );
+  VERIFY( mm1.size() == 8 );
+  iterator it2 = mm1.find("tillsammans");
+  VERIFY( it2 == mm1.end() );
+
+  // Must work (see DR 526)
+  iterator it3 = mm1.find("belonging (no longer mix)");
+  VERIFY( it3 != mm1.end() );
+  VERIFY( mm1.erase(it3->first) == 1 );
+  VERIFY( mm1.size() == 7 );
+  it3 = mm1.find("belonging (no longer mix)");
+  VERIFY( it3 == mm1.end() );
+
+  VERIFY( !mm1.erase("abra") );
+  VERIFY( mm1.size() == 7 );
+
+  VERIFY( !mm1.erase("eeilo") );
+  VERIFY( mm1.size() == 7 );
+
+  VERIFY( mm1.erase("because to why") == 1 );
+  VERIFY( mm1.size() == 6 );
+  iterator it4 = mm1.find("because to why");
+  VERIFY( it4 == mm1.end() );
+
+  iterator it5 = mm1.find("umbra/penumbra");
+  iterator it6 = mm1.find("one line behind");
+  VERIFY( it5 != mm1.end() );
+  VERIFY( it6 != mm1.end() );
+
+  VERIFY( mm1.find("the stockholm syndrome") != mm1.end() );
+  VERIFY( mm1.find("a cereous night") != mm1.end() );
+  VERIFY( mm1.find("the way you are when") != mm1.end() );
+  VERIFY( mm1.find("a cereous night") != mm1.end() );
+
+  VERIFY( mm1.erase(it5->first) == 1 );
+  VERIFY( mm1.size() == 5 );
+  it5 = mm1.find("umbra/penumbra");
+  VERIFY( it5 == mm1.end() );
+
+  VERIFY( mm1.erase(it6->first) == 1 );
+  VERIFY( mm1.size() == 4 );
+  it6 = mm1.find("one line behind");
+  VERIFY( it6 == mm1.end() );
+
+  iterator it7 = mm1.begin();
+  iterator it8 = it7;
+  ++it8;
+  iterator it9 = it8;
+  ++it9;
+
+  VERIFY( mm1.erase(it8->first) == 1 );
+  VERIFY( mm1.size() == 3 );
+  VERIFY( ++it7 == it9 );
+
+  iterator it10 = it9;
+  ++it10;
+  iterator it11 = it10;
+
+  VERIFY( mm1.erase(it9->first) == 1 );
+  VERIFY( mm1.size() == 2 );
+  VERIFY( ++it10 == mm1.end() );
+
+  VERIFY( mm1.erase(mm1.begin()) != mm1.end() );  
+  VERIFY( mm1.size() == 1 );
+  VERIFY( mm1.begin() == it11 );
+
+  VERIFY( mm1.erase(mm1.begin()->first) == 1 );  
+  VERIFY( mm1.size() == 0 );
+  VERIFY( mm1.begin() == mm1.end() );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/tr1/6_containers/unordered_multiset/erase/1.cc b/libstdc++-v3/testsuite/tr1/6_containers/unordered_multiset/erase/1.cc
new file mode 100644
index 0000000..f98e5c2
--- /dev/null
+++ b/libstdc++-v3/testsuite/tr1/6_containers/unordered_multiset/erase/1.cc
@@ -0,0 +1,130 @@
+// 2007-02-22  Paolo Carlini  <pcarlini@suse.de> 
+//
+// Copyright (C) 2007 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
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 2, or (at your option)
+// any later version.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING.  If not, write to the Free
+// Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
+// USA.
+
+// 6.3.4.5  Class template unordered_multiset
+
+#include <tr1/unordered_set>
+#include <string>
+#include <testsuite_hooks.h>
+
+// In the occasion of libstdc++/25896
+void test01()
+{
+  bool test __attribute__((unused)) = true;
+  
+  typedef std::tr1::unordered_multiset<std::string> Mset;
+  typedef Mset::iterator       iterator;
+  typedef Mset::const_iterator const_iterator;
+
+  Mset ms1;
+  
+  ms1.insert("because to why");
+  ms1.insert("the stockholm syndrome");
+  ms1.insert("a cereous night");
+  ms1.insert("eeilo");
+  ms1.insert("protean");
+  ms1.insert("the way you are when");
+  ms1.insert("tillsammans");
+  ms1.insert("umbra/penumbra");
+  ms1.insert("belonging (no longer mix)");
+  ms1.insert("one line behind");
+  VERIFY( ms1.size() == 10 );
+
+  VERIFY( ms1.erase("eeilo") == 1 );
+  VERIFY( ms1.size() == 9 );
+  iterator it1 = ms1.find("eeilo");
+  VERIFY( it1 == ms1.end() );
+
+  VERIFY( ms1.erase("tillsammans") == 1 );
+  VERIFY( ms1.size() == 8 );
+  iterator it2 = ms1.find("tillsammans");
+  VERIFY( it2 == ms1.end() );
+
+  // Must work (see DR 526)
+  iterator it3 = ms1.find("belonging (no longer mix)");
+  VERIFY( it3 != ms1.end() );
+  VERIFY( ms1.erase(*it3) == 1 );
+  VERIFY( ms1.size() == 7 );
+  it3 = ms1.find("belonging (no longer mix)");
+  VERIFY( it3 == ms1.end() );
+
+  VERIFY( !ms1.erase("abra") );
+  VERIFY( ms1.size() == 7 );
+
+  VERIFY( !ms1.erase("eeilo") );
+  VERIFY( ms1.size() == 7 );
+
+  VERIFY( ms1.erase("because to why") == 1 );
+  VERIFY( ms1.size() == 6 );
+  iterator it4 = ms1.find("because to why");
+  VERIFY( it4 == ms1.end() );
+
+  iterator it5 = ms1.find("umbra/penumbra");
+  iterator it6 = ms1.find("one line behind");
+  VERIFY( it5 != ms1.end() );
+  VERIFY( it6 != ms1.end() );
+
+  VERIFY( ms1.find("the stockholm syndrome") != ms1.end() );
+  VERIFY( ms1.find("a cereous night") != ms1.end() );
+  VERIFY( ms1.find("the way you are when") != ms1.end() );
+  VERIFY( ms1.find("a cereous night") != ms1.end() );
+
+  VERIFY( ms1.erase(*it5) == 1 );
+  VERIFY( ms1.size() == 5 );
+  it5 = ms1.find("umbra/penumbra");
+  VERIFY( it5 == ms1.end() );
+
+  VERIFY( ms1.erase(*it6) == 1 );
+  VERIFY( ms1.size() == 4 );
+  it6 = ms1.find("one line behind");
+  VERIFY( it6 == ms1.end() );
+
+  iterator it7 = ms1.begin();
+  iterator it8 = it7;
+  ++it8;
+  iterator it9 = it8;
+  ++it9;
+
+  VERIFY( ms1.erase(*it8) == 1 );
+  VERIFY( ms1.size() == 3 );
+  VERIFY( ++it7 == it9 );
+
+  iterator it10 = it9;
+  ++it10;
+  iterator it11 = it10;
+
+  VERIFY( ms1.erase(*it9) == 1 );
+  VERIFY( ms1.size() == 2 );
+  VERIFY( ++it10 == ms1.end() );
+
+  VERIFY( ms1.erase(ms1.begin()) != ms1.end() );  
+  VERIFY( ms1.size() == 1 );
+  VERIFY( ms1.begin() == it11 );
+
+  VERIFY( ms1.erase(*ms1.begin()) == 1 );  
+  VERIFY( ms1.size() == 0 );
+  VERIFY( ms1.begin() == ms1.end() );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/tr1/6_containers/unordered_set/erase/1.cc b/libstdc++-v3/testsuite/tr1/6_containers/unordered_set/erase/1.cc
new file mode 100644
index 0000000..823a9b8
--- /dev/null
+++ b/libstdc++-v3/testsuite/tr1/6_containers/unordered_set/erase/1.cc
@@ -0,0 +1,130 @@
+// 2007-02-22  Paolo Carlini  <pcarlini@suse.de> 
+//
+// Copyright (C) 2007 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
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 2, or (at your option)
+// any later version.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING.  If not, write to the Free
+// Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
+// USA.
+
+// 6.3.4.3  Class template unordered_set
+
+#include <tr1/unordered_set>
+#include <string>
+#include <testsuite_hooks.h>
+
+// In the occasion of libstdc++/25896
+void test01()
+{
+  bool test __attribute__((unused)) = true;
+  
+  typedef std::tr1::unordered_set<std::string> Set;
+  typedef Set::iterator       iterator;
+  typedef Set::const_iterator const_iterator;
+
+  Set s1;
+  
+  s1.insert("because to why");
+  s1.insert("the stockholm syndrome");
+  s1.insert("a cereous night");
+  s1.insert("eeilo");
+  s1.insert("protean");
+  s1.insert("the way you are when");
+  s1.insert("tillsammans");
+  s1.insert("umbra/penumbra");
+  s1.insert("belonging (no longer mix)");
+  s1.insert("one line behind");
+  VERIFY( s1.size() == 10 );
+
+  VERIFY( s1.erase("eeilo") == 1 );
+  VERIFY( s1.size() == 9 );
+  iterator it1 = s1.find("eeilo");
+  VERIFY( it1 == s1.end() );
+
+  VERIFY( s1.erase("tillsammans") == 1 );
+  VERIFY( s1.size() == 8 );
+  iterator it2 = s1.find("tillsammans");
+  VERIFY( it2 == s1.end() );
+
+  // Must work (see DR 526)
+  iterator it3 = s1.find("belonging (no longer mix)");
+  VERIFY( it3 != s1.end() );
+  VERIFY( s1.erase(*it3) == 1 );
+  VERIFY( s1.size() == 7 );
+  it3 = s1.find("belonging (no longer mix)");
+  VERIFY( it3 == s1.end() );
+
+  VERIFY( !s1.erase("abra") );
+  VERIFY( s1.size() == 7 );
+
+  VERIFY( !s1.erase("eeilo") );
+  VERIFY( s1.size() == 7 );
+
+  VERIFY( s1.erase("because to why") == 1 );
+  VERIFY( s1.size() == 6 );
+  iterator it4 = s1.find("because to why");
+  VERIFY( it4 == s1.end() );
+
+  iterator it5 = s1.find("umbra/penumbra");
+  iterator it6 = s1.find("one line behind");
+  VERIFY( it5 != s1.end() );
+  VERIFY( it6 != s1.end() );
+
+  VERIFY( s1.find("the stockholm syndrome") != s1.end() );
+  VERIFY( s1.find("a cereous night") != s1.end() );
+  VERIFY( s1.find("the way you are when") != s1.end() );
+  VERIFY( s1.find("a cereous night") != s1.end() );
+
+  VERIFY( s1.erase(*it5) == 1 );
+  VERIFY( s1.size() == 5 );
+  it5 = s1.find("umbra/penumbra");
+  VERIFY( it5 == s1.end() );
+
+  VERIFY( s1.erase(*it6) == 1 );
+  VERIFY( s1.size() == 4 );
+  it6 = s1.find("one line behind");
+  VERIFY( it6 == s1.end() );
+
+  iterator it7 = s1.begin();
+  iterator it8 = it7;
+  ++it8;
+  iterator it9 = it8;
+  ++it9;
+
+  VERIFY( s1.erase(*it8) == 1 );
+  VERIFY( s1.size() == 3 );
+  VERIFY( ++it7 == it9 );
+
+  iterator it10 = it9;
+  ++it10;
+  iterator it11 = it10;
+
+  VERIFY( s1.erase(*it9) == 1 );
+  VERIFY( s1.size() == 2 );
+  VERIFY( ++it10 == s1.end() );
+
+  VERIFY( s1.erase(s1.begin()) != s1.end() );  
+  VERIFY( s1.size() == 1 );
+  VERIFY( s1.begin() == it11 );
+
+  VERIFY( s1.erase(*s1.begin()) == 1 );  
+  VERIFY( s1.size() == 0 );
+  VERIFY( s1.begin() == s1.end() );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}